| the production and characterisation of an immobilised chaperonin system. | here we report a method of immobilising the chaperonins groel and groes to a glass matrix. the immobilised chaperone system has been used to successfully refold target proteins denatured by guanidine hydrochloride and produce substantially higher levels of active protein than occur on dilution into aqueous solution alone. the chaperone system has been shown to refold proteins from each of the three categories of groel substrate. the refolding of the enzyme glycerol dehydrogenase from bacillus st ... | 1999 | 9878699 |
| primary structure, expression, and site-directed mutagenesis of inorganic pyrophosphatase from bacillus stearothermophilus. | the complete primary structure of inorganic pyrophosphatase [ec 3.6. 1.1] from bacillus stearothermophilus (atcc 12016) was determined at the amino acid level by automated edman degradation. the subunit of the enzyme consists of 164 amino acid residues with a calculated molecular mass of 18,796. the amino acid sequence of the enzyme is almost identical to that of thermophilic bacterium ps-3. based on the determined primary structure, a pcr-amplified semi-synthetic gene was constructed and expres ... | 1999 | 9880796 |
| hydrophobic interactions of val75 are critical for oligomeric thermostability of inorganic pyrophosphatase from bacillus stearothermophilus. | to determine the role of val75 in the oligomeric structure of trimeric inorganic pyrophosphatase (ppase) [ec 3.6.1.1] from bacillus stearothermophilus (bst.), we used site-directed mutagenesis to prepare variants in which val75 was replaced by ala, phe, leu, ile, lys, gln, and asp. as a result, the variants in which valine is replaced by hydrophobic residues such as ala, phe, leu, and ile (v75a, f, l, and i) show almost the same level of enzyme activity and thermostability as the wild type enzym ... | 1999 | 9880797 |
| evolutionary molecular engineering by random elongation mutagenesis. | we describe a new method of random mutagenesis that employs the addition of peptide tails with random sequences to the c-terminal of enzyme molecules. a mutant population of catalase i from bacillus stearothermophilus prepared by this method has a diversity in thermostability and enzyme activity equal to that obtained after random point mutagenesis. when a triple mutant of catalase i (i108t/d130n/1222t)-the thermostability of which is much lower than that of the wild type-was subjected to random ... | 1999 | 9920270 |
| identification by site-directed mutagenesis of amino acid residues in ribosomal protein l2 that are essential for binding to 23s ribosomal rna. | the ribosomal protein l2 (bstl2) from bacillus stearothermophilus is a primary 23s rrna binding protein. we made use of site-directed mutagenesis to identify essential basic and aromatic amino acid residues for 23s rrna binding. four mutants, r68q, k70q, r86q, and r155q, in which arg-68, lys-70, arg-86, and arg-155, respectively, are replaced by the gln residue. showed reduced binding affinities as compared with that of the wild type bstl2 (a binding constant k=8.93 microm(-1)): k values of thes ... | 1998 | 9920395 |
| [absorption of nitric oxide by a strain of bacillus stearothermophilus and its use in a bioreactor for purifying air]. | a new bacillus stearothermophilus strain, inmi 50, was isolated and identified. cells of this strain immobilized on a ceramic carrier demonstrated a high no uptake in a bioreactor. the bioreactor volume was 4 l; air flow, 100 l/h; initial no concentration, 5 ppm; and temperature, 60 degrees c. glycerol or 1,2-propanediol was used as carbon and energy source. the uptake of no was 60-90% of the initial concentration over six months of continuous operation of the bioreactor. the developed procedure ... | 1998 | 9929891 |
| crystallization and preliminary x-ray crystallographic study of a 23s rrna binding domain of the ribosomal protein l2 from bacillus stearothermophilus. | ribosomal protein l2 from bacillus stearothermophilus, a single polypeptide chain with 275 amino acid residues, is a primary 23s rrna-binding protein in the large ribosomal subunit. crystals of a 23s rrna binding domain (bstl2-rbd: positions 60-201) of the ribosomal protein l2 from b. stearothermophilus overexpressed in escherichia coli have been grown in 0.1 m mes (ph 6.5) containing 15% polyethylene glycol 20 000. the crystals diffract to 2.3-a resolution on a synchrotron x-ray source. the cry ... | 1998 | 9931278 |
| role of lysine 39 of alanine racemase from bacillus stearothermophilus that binds pyridoxal 5'-phosphate. chemical rescue studies of lys39 --> ala mutant. | the lysine residue binding with the cofactor pyridoxal 5'-phosphate (plp) plays an important role in catalysis, such as in the transaldimination and abstraction of alpha-hydrogen from a substrate amino acid in plp-dependent enzymes. we studied the role of lys39 of alanine racemase (ec 5.1.1.1) from bacillus stearothermophilus, the plp-binding residue of the enzyme, by replacing it site-specifically with alanine and characterizing the resultant k39a mutant enzyme. the mutant enzyme turned out to ... | 1999 | 9933615 |
| experimental evolution of a dense cluster of residues in tyrosyl-trna synthetase: quantitative effects on activity, stability and dimerization. | a dense cluster of eight residues was identified at the crossing of two alpha-helices in tyrosyl-trna synthetase (tyrrs) from the thermophile bacillus stearothermophilus. its mechanism of evolution was characterized. four residues of this cluster are not conserved in tyrrs from the mesophile escherichia coli. the corresponding mutations were constructed in tyrrs(delta1), a derivative of tyrrs from b. stearothermophilus in which the anticodon binding domain is deleted. mutations i52l (i.e. ile52 ... | 1999 | 9973571 |
| the bacillus stearothermophilus mannitol regulator, mtlr, of the phosphotransferase system. a dna-binding protein, regulated by hpr and iicbmtl-dependent phosphorylation. | d-mannitol is taken up by bacillus stearothermophilus and phosphorylated via a phosphoenolpyruvate-dependent phosphotransferase system (pts). the genes involved in the mannitol uptake were recently cloned and sequenced. one of the genes codes for a putative transcriptional regulator, mtlr. the presence of a dna binding helix-turn-helix motif and two antiterminator-like pts regulation domains, suggest that mtlr is a dna-binding protein, the activity of which can be regulated by phosphorylation by ... | 1999 | 9988713 |
| principles of quasi-equivalence and euclidean geometry govern the assembly of cubic and dodecahedral cores of pyruvate dehydrogenase complexes. | the pyruvate dehydrogenase multienzyme complex (mr of 5-10 million) is assembled around a structural core formed of multiple copies of dihydrolipoyl acetyltransferase (e2p), which exhibits the shape of either a cube or a dodecahedron, depending on the source. the crystal structures of the 60-meric dihydrolipoyl acyltransferase cores of bacillus stearothermophilus and enterococcus faecalis pyruvate dehydrogenase complexes were determined and revealed a remarkably hollow dodecahedron with an outer ... | 1999 | 9990008 |
| suitability of the charm hvs and a microbiological multiplate system for detection of residues in raw milk at eu maximum residue levels. | in this paper we assessed the suitability of the charm hvs and a newly developed microbiological multiplate system as post-screening tests to confirm the presence of residues in raw milk at or near the maximum permissible residue level (mrl). the multiplate system is composed of bacillus stearothermophilus var. calidolactis plate at ph 8.0 for detection of beta-lactam antibiotics and tylosin, bacillus cereus plate at ph 6.0 for detection of tetracyclines, micrococcus luteus plate at ph 8.0 for d ... | 1999 | 9990703 |
| reconstitution of functional 50s ribosomes from in vitro transcripts of bacillus stearothermophilus 23s rrna. | in vitro transcripts of bacillus stearothermophilus 23s rrna can be reconstituted into catalytically active 50s ribosomal subunits with an efficiency only 3-4-fold lower than that of natural 23s rrna. thus, post-transcriptional modifications in 23s rrna are not essential for the assembly or function of the 50s subunit of the ribosome. this reconstitution sytem has been used to characterize the peptidyl transferase activity of site-directed mutations in 23s rrna at positions g2252, u2506, u2584, ... | 1999 | 10026257 |
| plasmid replication initiator protein repd increases the processivity of pcra dna helicase. | the replication initiator protein repd encoded by the staphylococcus chloramphenicol resistance plasmid pc221 stimulates the helicase activity of the bacillus stearothermophilus pcra dna helicase in vitro. this stimulatory effect seems to be specific for pcra and differs from the stimulatory effect of the escherichia coli ribosomal protein l3. whereas l3 stimulates the pcra helicase activity by promoting co-operative pcra binding onto its dna substrate, repd stimulates the pcra helicase activity ... | 1999 | 10037801 |
| cloning, overexpression, purification, and physicochemical characterization of a cold shock protein homolog from the hyperthermophilic bacterium thermotoga maritima. | thermotoga maritima (tm) expresses a 7 kda monomeric protein whose 18 n-terminal amino acids show 81% identity to n-terminal sequences of cold shock proteins (csps) from bacillus caldolyticus and bacillus stearothermophilus. there were only trace amounts of the protein in thermotoga cells grown at 80 degrees c. therefore, to perform physicochemical experiments, the gene was cloned in escherichia coli. a dna probe was produced by pcr from genomic tm dna with degenerated primers developed from the ... | 1999 | 10048332 |
| cloning of bacillus stearothermophilus ctaa and heme a synthesis with the ctaa protein produced in escherichia coli. | the bacillus stearothermophilus ctaa gene, which is required for heme a synthesis, was found upstream of the ctabcdef/caaeabcd gene cluster as in b. subtilis and b. firmus. the deduced protein sequence indicate that ctaa is a 35-kda intrinsic membrane protein with seven hydrophobic segments. alignment of ctaa sequences showed conserved residues including histidines that may be involved in heme b binding and substrate binding. expression of ctaa in e. coli resulted in increased formation of a mem ... | 1999 | 10052128 |
| effect of steam sterilization inside the turbine chambers of dental turbines. | it has been demonstrated that contamination of the insides of high-speed dental turbines occurs and that bacteria as well as viruses may remain infectious when expelled from such turbines during subsequent use. consequently, it has been widely recommended that a high-speed turbine be sterilized after each patient. the purpose of this study was to evaluate the effect of steam autoclaving on a high-speed dental turbine with a contaminated turbine chamber. | 1999 | 10052374 |
| the active site of phosphorylating glyceraldehyde-3-phosphate dehydrogenase is not designed to increase the nucleophilicity of a serine residue. | changing a catalytic cysteine into a serine, and vice versa, generally leads to a dramatic decrease in enzymatic efficiency. except a study done on thiol subtilisin, no extensive study was carried out for determining whether the decrease in activity is due to a low nucleophilicity of the introduced amino acid. in the present study, cys149 of glyceraldehyde-3-phosphate dehydrogenase from bacillus stearothermophilus was converted into a ser residue. this leads to a drastic reduction of the kcat va ... | 1999 | 10068447 |
| conformational analysis of peptide fragments derived from the peripheral subunit-binding domain from the pyruvate dehydrogenase multienzyme complex of bacillus stearothermophilus: evidence for nonrandom structure in the unfolded state. | there is currently a great deal of interest in the early events in protein folding. two issues that have generated particular interest are the nature of the unfolded state under native conditions and the role of local interactions in folding. here, we report the results of a study of a set of peptides derived from a small two-helix protein, the peripheral subunit-binding domain of the pyruvate dehydrogenase multienzyme complex. five peptides of overlapping sequence were prepared, including seque ... | 1999 | 10070261 |
| the three-dimensional structure of the rna-binding domain of ribosomal protein l2; a protein at the peptidyl transferase center of the ribosome. | ribosomal protein l2 is the largest protein component in the ribosome. it is located at or near the peptidyl transferase center and has been a prime candidate for the peptidyl transferase activity. it binds directly to 23s rrna and plays a crucial role in its assembly. the three-dimensional structure of the rna-binding domain of l2 from bacillus stearothermophilus has been determined at 2.3 a resolution by x-ray crystallography using the selenomethionyl mad method. the rna-binding domain of l2 c ... | 1999 | 10075918 |
| development of an arming yeast strain for efficient utilization of starch by co-display of sequential amylolytic enzymes on the cell surface. | the construction of a whole-cell biocatalyst with its sequential reaction has been performed by the genetic immobilization of two amylolytic enzymes on the yeast cell surface. a recombinant strain of saccharomyces cerevisiae that displays glucoamylase and alpha-amylase on its cell surface was constructed and its starch-utilizing ability was evaluated. the gene encoding rhizopus oryzae glucoamylase, with its own secretion signal peptide, and a truncated fragment of the alpha-amylase gene from bac ... | 1999 | 10077821 |
| structure of a michaelis complex analogue: propionate binds in the substrate carboxylate site of alanine racemase. | the structure of alanine racemase from bacillus stearothermophilus with the inhibitor propionate bound in the active site was determined by x-ray crystallography to a resolution of 1.9 a. the enzyme is a homodimer in solution and crystallizes with a dimer in the asymmetric unit. both active sites contain a pyridoxal 5'-phosphate (plp) molecule in aldimine linkage to lys39 as a protonated schiff base, and the ph-independence of uv-visible absorption spectra suggests that the protonated plp-lys39 ... | 1999 | 10079072 |
| microbiological efficacy of superheated steam. i. communication: results with spores of bacillus subtilis and bacillus stearothermophilus and with spore earth. | for the spores of bacillus subtilis and bacillus stearothermophilus as well as for spore earth (acc. din 58,946 part 4 of august 1982), the dependence of resistance on the superheating of the steam used to kill germs was determined. a material (glass fibre fleece) was used as the germ carrier which does not superheat on contact with steam. the temperature of the saturated steam was 100 degrees c (b. subtilis) and 120 degrees c (b. stearothermophilus and spore earth). the yardstick for the resist ... | 1999 | 10084207 |
| the high-resolution structure of dna-binding protein hu from bacillus stearothermophilus. | protein hu is a ubiquitous prokaryotic protein which controls the architecture of genomic dna. it binds dna non-specifically and promotes the bending and supercoiling of the double helical structure. hu is involved in many dna-associated cellular processes, including replication, transcription and the packaging of dna into chromosome-like structures. originally determined at medium resolution, the crystal structure of hu has now been refined at 2.0 a resolution. the high-resolution structure sho ... | 1999 | 10089311 |
| crystallization and preliminary x-ray analysis of alpha-d-glucuronidase from bacillus stearothermophilus t-6. | alpha-d-glucuronidases cleave the alpha-1,2-glycosidic bond of the 4-o-methyl-alpha-d-glucuronic acid side chain in xylan. of the xylan-debranching hydrolases, these enzymes are the least studied and characterized. the alpha-glucuronidase gene (agua) from bacillus stearothermophilus t-6 has been cloned, sequenced and overproduced in escherichia coli. the gene encodes for a protein of 679 amino acids with a calculated molecular weight of 78480 and a pi of 5.42. alpha-glucuronidase t-6 shows high ... | 1999 | 10089319 |
| cloning, expression and crystallization of pyrimidine nucleoside phosphorylase from bacillus stearothermophilus. | pyrimidine nucleoside phosphorylase (pynp) from b. stearothermophilus has been cloned and purified for crystallization. crystals of a potential protein-inhibitor complex have been prepared by co-crystallization techniques using the substrate analog pseudouridine. these crystals provide good-quality diffraction images to 2.7 a and belong to space group p21. the asymmetric unit contains the dimer structure of pynp with unit-cell parameters a = 53.9, b = 71.9, c = 123.3 a and beta = 96.9 degrees. | 1999 | 10089427 |
| crystallization of the regulatory and effector domains of the key sporulation response regulator spo0a. | the key response-regulator gene of sporulation, spo0a, has been cloned from bacillus stearothermophilus and the encoded protein purified. the dna-binding and phospho-acceptor domains of spo0a have been prepared by tryptic digestion of the intact protein and subsequently crystallized in forms suitable for x-ray crystallographic studies. the dna-binding domain has been crystallized in two forms, one of which diffracts x-rays to beyond 2. 5 a spacing. the crystals of the phospho-acceptor domain dif ... | 1999 | 10089466 |
| preliminary characterization by x-ray diffraction and raman spectroscopy of a crystalline complex of bacillus stearothermophilus initiation factor 2 c-domain and fmet-trnafmet. | bacillus stearothermophilus translation initiation factor 2 (if2) specifically binds initiator fmet-trnafmet and positions it into the ribosomal peptidyl site in the course of the initiation of protein biosynthesis. the isolated c-terminal domain of if2 is capable of binding fmet-trnafmet, as shown by rnase a and hydrolysis protection experiments. in the presence of fmet-trnafmet, the if2 c-domain yielded orthorhombic crystals of space group i222 (i212121) diffracting to 3.4 a resolution. the ex ... | 1999 | 10089478 |
| the bacillus stearothermophilus replicative helicase: cloning, overexpression and activity. | as part of biochemical and structural studies of the primosome of a gram positive bacterial species, we describe the cloning of the bacillus stearothermophilus replicative helicase, dnab. the protein is 45% and 82% identical to the escherichia coli and b. subtilis replicative helicases, respectively. recombinant dnab was purified and shown to be an active helicase. | 1999 | 10095066 |
| cloning, expression, and purification of bacillus stearothermophilus dna primase and crystallization of the zinc-binding domain. | the dnag gene encoding dna primase has been isolated from chromosomal dna of bacillus stearothermophilus and its entire nucleotide sequence determined. the deduced amino acid sequence comprised 597 amino acid residues and the molecular mass was calculated to be 67068 da. b. stearothermophilus primase was overexpressed in escherichia coli and purified to homogeneity. the n-terminal 12 kda zinc-binding domain has been crystallized. the crystals are of the monoclinic space group p21 with cell dimen ... | 1999 | 10095067 |
| an escherichia coli host strain useful for efficient overproduction of secreted recombinant protein. | periplasmic secretion of overexpressed bacillus stearothermophilus alpha-amylase was analyzed in batch and fed-batch cultivations of escherichia coli mg1655:pcss4-p and the mutant strain cwml2:pcss4-p. under all conditions investigated, growth and product formation of mg1655:pcss4-p were severely impaired by heterologous protein expression and/or processing, while e. coli cwml2:pcss4-p was found to be more robust and to accumulate 2- to 3-fold higher maximum alpha-amylase levels. while this stra ... | 1998 | 10099351 |
| optimization of a heterogeneous reaction system for the production of optically active d-amino acids using thermostable d-hydantoinase. | a thermostable d-hydantoinase from bacillus stearothermophilus sd-1 was previously mass-produced by batch cultivation of the recombinant e. coli harboring the gene encoding the enzyme (lee et al., 1997). in this work, we attempted to optimize the process for the production of n-carbamoyl-d-p-hydroxyphenylglycine, which is readily hydrolyzed to d-p-hydroxyphenylglycine under acidic conditions, from 5-(4-hydroxyphenyl)hydantoin using the mass-produced d-hydantoinase. in an effort to overcome the l ... | 1998 | 10099482 |
| effect of temperature on the saccharide composition obtained after alpha-amylolysis of starch | the hydrolysis of starch to low-molecular-weight products (normally characterised by their dextrose equivalent (de), which is directly related to the number-average molecular mass) was studied at different temperatures. amylopectin potato starch, lacking amylose, was selected because of its low tendency towards retrogradation at lower temperatures. bacillus licheniformis alpha-amylase was added to 10% [w/w] gelatinised starch solutions. the hydrolysis experiments were done at 50, 70, and 90 degr ... | 1999 | 10099614 |
| secondary structure of the c-terminal domain of the tyrosyl-transfer rna synthetase from bacillus stearothermophilus: a novel type of anticodon binding domain? | the tyrosyl-trna synthetase catalyzes the activation of tyrosine and its coupling to the cognate trna. the enzyme is made of two domains: an n-terminal catalytic domain and a c-terminal domain that is necessary for trna binding and for which it was not possible to determine the structure by x-ray crystallography. we determined the secondary structure of the c-terminal domain of the tyrosyl-trna synthetase from bacillus stearothermophilus by nuclear magnetic resonance methods and found that it is ... | 1999 | 10100619 |
| self-assembly product formation of the bacillus stearothermophilus pv72/p6 s-layer protein sbsa in the course of autolysis of bacillus subtilis. | in order to achieve high level expression and to study the release of a protein capable of self-assembly, the gene encoding the crystalline cell surface (s-layer) protein sbsa of bacillus stearothermophilus pv72/p6, including its signal sequence, was cloned and expressed in bacillus subtilis. to obtain high level expression, a tightly regulated, xylose-inducible, stably replicating multicopy-plasmid vector was constructed. after induction of expression, the s-layer protein made up about 15% of t ... | 1999 | 10188248 |
| evidence for a two-base mechanism involving tyrosine-265 from arginine-219 mutants of alanine racemase. | a positively charged residue, r219, was found to interact with the pyridine nitrogen of pyridoxal phosphate in the structure of alanine racemase from bacillus stearothermophilus [shaw et al. (1997) biochemistry 36, 1329-1342]. three site-directed mutants, r219k, r219a, and r219e, have been characterized and compared to the wild type enzyme (wt) to investigate the role of r219 in catalysis. the r219k mutation is functionally conservative, retaining approximately 25% of the wt activity. the r219a ... | 1999 | 10194319 |
| nativelike structure and stability in a truncation mutant of a protein minidomain: the peripheral subunit-binding domain. | despite its small size, the peripheral subunit-binding domain from the dihydrolipoamide acetyltransferase component of the bacillus stearothermophilus pyruvate dehydrogenase multienzyme complex adopts a unique, compact structure. to determine whether the full 43 residue sequence is required for the domain to adopt a stable, nativelike structure, 3 proteins of different lengths were prepared. psbd41 corresponds to residues 3-43 of the domain, psbd36 spans residues 6-41, and psbd33 comprises resid ... | 1999 | 10194328 |
| high-resolution crystals of the hu mutant k38n from bacillus stearothermophilus. | the dna-binding protein hu is ubiquitous in the prokaryotic cell. it is a major protein component of isolated nucleoids and is believed to control the tertiary structure of prokaryotic dna. the bacillus stearothermophilus hu (bsthu) mutants obtained by mutagenesis have been investigated. crystallization experiments of bsthu-k38n (lys38 is substituted with asn) resulted in two forms of crystals suitable for high-resolution x-ray analysis. the first form belongs to the monoclinic space group c2 wi ... | 1999 | 10196119 |
| cloning of a tellurite resistance determinant from bacillus stearothermophilus v in escherichia coli. | a potassium tellurite-resistance determinant was isolated from bacillus stearothermophilus v and cloned in escherichia coli. transformed cells formed black colonies when grown on solid media containing permissive tellurite concentrations. the resistance determinant was contained in a b. stearothermophilus v chromosomal dna fragment of 7 kb. | 1999 | 10205661 |
| stabilizing effect of an s-layer on liposomes towards thermal or mechanical stress. | isolated subunits of the crystalline cell surface layer (s-layer) protein of bacillus stearothermophilus pv72/p2 were recrystallized on positively charged unilamellar liposomes. liposomes were composed of dipalmitoylphosphatidylcholine (dppc), cholesterol and hexadecylamine (hda) in a molar ratio of 10:5:4 and they were prepared by the dehydration-rehydration method followed by an extrusion procedure. the s-layer protein to dppc ratio was 5.7 nmol/micromol which approximately corresponds to the ... | 1999 | 10209215 |
| characterization and modelling of vant: a novel, membrane-bound, serine racemase from vancomycin-resistant enterococcus gallinarum bm4174. | sequence determination of a region downstream from the vanxyc gene in enterococcus gallinarum bm4174 revealed an open reading frame, designated vant, that encodes a 698-amino-acid polypeptide with an amino-terminal domain containing 10 predicted transmembrane segments. the protein contained a highly conserved pyridoxal phosphate attachment site in the c-terminal domain, typical of alanine racemases. the protein was overexpressed in escherichia coli, and serine racemase activity was detected in t ... | 1999 | 10209740 |
| transglycosylation reactions of bacillus stearothermophilus maltogenic amylase with acarbose and various acceptors. | it was observed that bacillus stearothermophilus maltogenic amylase cleaved the first glycosidic bond of acarbose to produce glucose and a pseudotrisaccharide (pts) that was transferred to c-6 of the glucose to give an alpha-(1-->6) glycosidic linkage and the formation of isoacarbose. the addition of a number of different carbohydrates to the digest gave transfer products in which pts was primarily attached alpha-(1-->6) to d-glucose, d-mannose, d-galactose, and methyl alpha-d-glucopyranoside. w ... | 1998 | 10209866 |
| gene structure and quinol oxidase activity of a cytochrome bd-type oxidase from bacillus stearothermophilus. | gram-positive thermophilic bacillus species contain cytochrome caa3-type cytochrome c oxidase as their main terminal oxidase in the respiratory chain. we previously identified and purified an alternative oxidase, cytochrome bd-type quinol oxidase, from a mutant of bacillus stearothermophilus defective in the caa3-type oxidase activity (j. sakamoto et al., fems microbiol. lett. 143 (1996) 151-158). compared with proteobacterial counterparts, b. stearothermophilus cytochrome bd showed lower molecu ... | 1999 | 10216161 |
| organization of genes for tetrapyrrole biosynthesis in gram--positive bacteria. | clusters of genes encoding enzymes for tetrapyrrole biosynthesis were cloned from bacillus sphaericus, bacillus stearothermophilus, brevibacillus brevis and paenibacillus macerans. the sequences of all hemx genes found, and of a 6.3 kbp hem gene cluster from p. macerans, were determined. the structure of the hem gene clusters was compared to that of other gram-positive bacteria. the bacillus and brevibacillus species have a conserved organization of the genes hemaxcdbl, required for biosynthesis ... | 1999 | 10217486 |
| the mycelium-associated streptomyces reticuli catalase-peroxidase, its gene and regulation by furs. | during early stages of growth, streptomyces reticuli synthesizes a hyphae-associated, haem-containing enzyme which exhibits catalase and peroxidase activities with broad substrate specificity (cpeb). the purified dimeric enzyme (160 kda) consists of two identical subunits. using anti-cpeb antibodies and an expression- as well as a mini-library, the corresponding cpeb gene was identified and sequenced. it encodes a protein of 740 aa with a molecular mass of 81.3 kda. the deduced protein shares th ... | 1999 | 10217488 |
| folding of the multidomain ribosomal protein l9: the two domains fold independently with remarkably different rates. | the folding and unfolding behavior of the multidomain ribosomal protein l9 from bacillus stearothermophilus was studied by a novel combination of stopped-flow fluorescence and nuclear magnetic resonance (nmr) spectroscopy. one-dimensional 1h spectra acquired at various temperatures show that the c-terminal domain unfolds at a lower temperature than the n-terminal domain (tm = 67 degrees c for the c-terminal domain, 80 degrees c for the n-terminal domain). nmr line-shape analysis was used to dete ... | 1999 | 10220353 |
| the crystal structure of a multifunctional protein: phosphoglucose isomerase/autocrine motility factor/neuroleukin. | phosphoglucose isomerase (pgi) plays a central role in both the glycolysis and the gluconeogenesis pathways. we present here the complete crystal structure of pgi from bacillus stearothermophilus at 2.3-a resolution. we show that pgi has cell-motility-stimulating activity on mouse colon cancer cells similar to that of endogenous autocrine motility factor (amf). pgi can also enhance neurite outgrowth on neuronal progenitor cells similar to that observed for neuroleukin. the results confirm that p ... | 1999 | 10318897 |
| structure of the arginine repressor from bacillus stearothermophilus. | the arginine repressor (argr) is a hexameric dna-binding protein that plays a multifunctional role in the bacterial cell. here, we present the 2.5 a structure of apo-argr from bacillus stearothermophilus and the 2.2 a structure of the hexameric argr oligomerization domain with bound arginine. this first view of intact argr reveals an approximately 32-symmetric hexamer of identical subunits, with six dna-binding domains surrounding a central oligomeric core. the difference in quaternary organizat ... | 1999 | 10331868 |
| structural and functional studies on the overproduced l11 protein from thermus thermophilus. | the l11 ribosomal protein from thermus thermophilus (tthl11) has been overproduced and purified to homogeneity using a two-step purification protocol. the overproduced protein carries a similar methylation pattern at lys-3 as does its homolog from escherichia coli. chymotrypsin digested only a small part of the tthl11 protein and did not cleave tthl11 into two peptides, as in the case of ecol11, but produced only a single n-terminal peptide. tryptic digestion of tthl11 also produced an n-termina ... | 1999 | 10333296 |
| purification and characterization of alkaline phosphatase from bacillus stearothermophilus. | soluble alkaline phosphatase from the thermophilic bacterium bacillus stearothermophilus was purified by a combination of chromatographic methods, and its properties were examined. the purified enzyme had specific activity of 4.43 micromol p-nitrophenol/min per mg of protein and seemed to be a single band on sds/page with a molecular mass of 32 kda. its apparent km for p-nitrophenyl phosphate was 1.114 mm. the enzyme exhibited an optimal ph of approx. 9.0 and exhibited its highest activity at 60 ... | 1999 | 10334954 |
| thermal resistance of bacterial spores in milk-based beverages supplemented with nisin. | the effect of nisin, added in the form of nisaplin, on the thermal resistance of bacterial spores and the effects of medium composition, exposure time, and ph on nisin enhancement of heat sensitivity were evaluated. nisin apparently required specific nutrients to sensitize spores to heat. for example, d130 degrees c values of approximately 10 s were observed in sodium phosphate buffer with and without 6% sucrose with no significant (p> or =0.05) differences detected as a result of increased nisi ... | 1999 | 10340669 |
| role of tyrosine 265 of alanine racemase from bacillus stearothermophilus. | tyrosine 265 (y265) of bacillus stearothermophilus is believed to serve as a catalytic base specific to the l-enantiomer of a substrate amino acid by removing (or returning) an alpha-hydrogen from (or to) the isomer on the basis of the x-ray structure of the enzyme [stamper, c.g., morollo, a.a., and ringe, d. (1998) biochemistry 37, 10438-10443]. we found that the y265-->ala mutant (y265a) enzyme is virtually inactive as a catalyst for alanine racemization. we examined the role of y265 further w ... | 1999 | 10348897 |
| risk analysis of the thermal sterilization process. analysis of factors affecting the thermal resistance of microorganisms. | a risk analysis was applied to experimental heat resistance data. this analysis is an approach for processing experimental thermobacteriological data in order to study the variability of d and z values of target microorganisms depending on the deviations range of environmental factors, to determine the critical factors and to specify their critical tolerance. this analysis is based on sets of sensitivity functions applied to a specific case of experimental data related to the thermoresistance of ... | 1999 | 10357273 |
| the glucuronic acid utilization gene cluster from bacillus stearothermophilus t-6. | a lambda-embl3 genomic library of bacillus stearothermophilus t-6 was screened for hemicellulolytic activities, and five independent clones exhibiting beta-xylosidase activity were isolated. the clones overlap each other and together represent a 23.5-kb chromosomal segment. the segment contains a cluster of xylan utilization genes, which are organized in at least three transcriptional units. these include the gene for the extracellular xylanase, xylanase t-6; part of an operon coding for an intr ... | 1999 | 10368143 |
| structure of the adenylation domain of an nad+-dependent dna ligase. | dna ligases catalyse phosphodiester bond formation between adjacent bases in nicked dna, thereby sealing the nick. a key step in the catalytic mechanism is the formation of an adenylated dna intermediate. the adenyl group is derived from either atp (in eucaryotes and archaea) or nad+4 (in bacteria). this difference in cofactor specificity suggests that dna ligase may be a useful antibiotic target. | 1999 | 10368271 |
| regulatory features of the trp operon and the crystal structure of the trp rna-binding attenuation protein from bacillus stearothermophilus. | characterization of both the cis and trans -acting regulatory elements indicates that the bacillus stearothermophilustrp operon is regulated by an attenuation mechanism similar to that which controls the trp operon in bacillus subtilis. secondary structure predictions indicate that the leader region of the trp mrna is capable of folding into terminator and anti- terminator rna structures. b. stearothermophilus also encodes an rna-binding protein with 77% sequence identity with the rna-binding pr ... | 1999 | 10369778 |
| bsesi, a restriction endonuclease from bacillus stearothermophilus jo 10-553, which recognizes the novel hexanucleotide sequence 5'-g(g/t)gc(a/c)c-3'. | a new restriction endonuclease bse si has been isolated from bacillus stearothermophilus jo10-553. bse si recognizes a degenerate hexanucleotide sequence 5'-g(g/t)gc(a/c)c-3' and cleaves dna to produce 3[prime]-protruding tetranucleotide ends. | 1999 | 10373580 |
| [homologous locus of genomes of bacillus subtilis and bacillus stearothermophilus, containing levansucrase and levanase genes]. | | 1999 | 10377564 |
| lys13 plays a crucial role in the functional adaptation of the thermophilic triose-phosphate isomerase from bacillus stearothermophilus to high temperatures. | the thermophilic triose-phosphate isomerases (tims) of bacillus stearothermophilus (btim) and thermotoga maritima (ttim) have been found to possess a his12-lys13 pair instead of the asn12-gly13 pair normally present in mesophilic tims. his12 in btim was proposed to prevent deamidation at high temperature, while the precise role of lys13 is unknown. to investigate the role of the his12 and lys13 pair in the enzyme's thermoadaptation, we reintroduced the "mesophilic residues" asn and gly into both ... | 1999 | 10383424 |
| disordered c-terminal domain of tyrosyl-trna synthetase: secondary structure prediction. | the c-terminal domain (residues 320-419) of tyrosyl-trna synthetase (tyrrs) from bacillus stearothermophilus is disordered in the crystal structure and involved in the binding of the anticodon arm of trna(tyr). the sequences of 11 tyrrss of prokaryotic or mitochondrial origins were aligned and the alignment showed the existence of conserved residues in the sequences of the c-terminal domains. a consensus could be deduced from the application of five programs of secondary structure prediction to ... | 1999 | 10385005 |
| the amino acidic substitution of cysteine 167 by serine (c167s) in bstvi restriction endonuclease of bacillus stearothermophilus v affects its conformation and thermostability. | the restriction endonuclease bstvi from bacillus stearothermophilus v contains three cysteine residues at positions 134, 167 and 180. titration of cys residues with dtnb showed that none of them are involved in disulphide bond formation. cysteine triplets 134 and 167 were modified by recombinant pcr to introduce a serine residue in each case. the mutated genes were cloned into pgem-t vector and transformed into e. coli jm109. even though pgem-t is not designed for expression, the mutant proteins ... | 1999 | 10385008 |
| mildly oxidized gapdh: the coupling of the dehydrogenase and acyl phosphatase activities. | the hydrogen peroxide-induced 'non-phosphorylating' activity of d-glyceraldehyde 3-phosphate dehydrogenase (gapdh) is shown to be a result of the successive action of two forms of the enzyme subunits: one catalyzing production of 1,3-bisphosphoglycerate, and the other performing its hydrolytic decomposition. the latter form is produced by mild oxidation of gapdh in the presence of a low hydrogen peroxide concentration when essential cys-149 is oxidized to the sulfenate derivative. the results ob ... | 1999 | 10386594 |
| alcoholysis reactions from starch with alpha-amylases. | the ability of alpha-amylases from different sources to carry out reactions of alcoholysis was studied using methanol as substrate. it was found that while the enzymes from aspergillus niger and aspergillus oryzae, two well-studied saccharifying amylases, are capable of alcoholysis reactions, the classical bacterial liquefying alpha-amylases from bacillus licheniformis and bacillus stearothermophilus are not. the effect of starch and methanol concentration, temperature and ph on the synthesis of ... | 1999 | 10386619 |
| selective association of protein molecules followed by mass spectrometry. | nanoflow electrospray mass spectrometry was used to monitor the formation of protein heterodimers of hu proteins from bacillus stearothermophilus and bacillus subtilis. this has enabled us to analyze both thermodynamic and kinetic features associated with the dissociation of homodimeric hu proteins. the results obtained correlate well with the kinetics of the protein dissociation process and the free energy difference between homo- and heterodimeric species anticipated from other studies. we sug ... | 1999 | 10386888 |
| probing the unfolding region in a thermolysin-like protease by site-specific immobilization. | protein stabilization by immobilization has been proposed to be most effective if the protein is attached to the carrier at that region where unfolding is initiated. to probe this hypothesis, we have studied the effects of site-specific immobilization on the thermal stability of mutants of the thermolysin-like protease from bacillus stearothermophilus (tlp-ste). this enzyme was chosen because previous studies had revealed which parts of the molecule are likely to be involved in the early steps o ... | 1999 | 10387069 |
| x-ray structure of novamyl, the five-domain "maltogenic" alpha-amylase from bacillus stearothermophilus: maltose and acarbose complexes at 1.7a resolution. | the three-dimensional structure of the bacillus stearothermophilus "maltogenic" alpha-amylase, novamyl, has been determined by x-ray crystallography at a resolution of 1.7 a. unlike conventional alpha-amylases from glycoside hydrolase family 13, novamyl exhibits the five-domain structure more usually associated with cyclodextrin glycosyltransferase. complexes of the enzyme with both maltose and the inhibitor acarbose have been characterized. in the maltose complex, two molecules of maltose are f ... | 1999 | 10387084 |
| structural studies on a 2,3-diphosphoglycerate independent phosphoglycerate mutase from bacillus stearothermophilus. | phosphoglycerate mutase (pgm), an important enzyme in the glycolytic pathway, catalyzes the transfer of a phosphate group between the 2 and the 3 positions of glyceric acid. the gene coding for the 2, 3-diphosphoglycerate independent monomeric pgm from bacillus stearothermophilus (57 kda), whose activity is extremely ph sensitive and has an absolute and specific requirement for mn2+, has been cloned and the enzyme overexpressed and purified to homogeneity. circular dichroism studies showed at mo ... | 1999 | 10388626 |
| introducing transglycosylation activity in a liquefying alpha-amylase. | by mutating ala-289 by phe or tyr in the bacillus stearothermophilus alpha-amylase, we induced this enzyme to perform alcoholytic reactions, a function not present in the wild-type enzyme. this residue was selected from homology analysis with neopullulanase, where the residue has been implicated in the control of transglycosylation [kuriki et al. (1996) j. biol. chem. 271, 17321-173291. we made some inferences about the importance of electrostatic and geometrical modifications in the active site ... | 1999 | 10403384 |
| crystal structure of the atpase domain of translation initiation factor 4a from saccharomyces cerevisiae--the prototype of the dead box protein family. | translation initiation factor 4a (elf4a) is the prototype of the dead-box family of proteins. dead-box proteins are involved in a variety of cellular processes including splicing, ribosome biogenesis and rna degradation. energy from atp hydrolysis is used to perform rna unwinding during initiation of mrna translation. the presence of elf4a is required for the 43s preinitiation complex to bind to and scan the mrna. | 1999 | 10404596 |
| nucleotide sequence, heterologous expression and novel purification of dna ligase from bacillus stearothermophilus(1). | the gene for dna ligase (ec 6.5.1.2) from thermophilic bacterium bacillus stearothermophilus nca1503 has been cloned and the complete nucleotide sequence determined. the ligase gene encodes a protein 670 amino acids in length. the gene was overexpressed in escherichia coli and the enzyme has been purified to homogeneity. preliminary characterisation confirms that it is a thermostable, nad(+)-dependent dna ligase. | 1999 | 10407164 |
| detection of antimicrobial activity in urine for epidemiologic studies of antibiotic use. | antibiotic resistance is the inevitable consequence of the selective pressure of antimicrobial drug use and the adaptive plasticity of the microorganisms. excessive and irrational use of antimicrobial drugs is a problem in all countries. it is particularly troublesome in developing countries where there is a heavy burden of infectious diseases. this study was designed to determine whether detection of antimicrobial activity in the urine might be a useful tool for epidemiologic studies of the int ... | 1999 | 10408993 |
| thermostable alpha-galactosidase from bacillus stearothermophilus nub3621: cloning, sequencing and characterization. | an alpha-galactosidase gene from the thermophilic bacterium bacillus stearothermophilus nub3621 was cloned, sequenced, expressed in escherichia coli and the recombinant protein was purified. the bacillus enzyme, designated agan, is similar to alpha-galactosidases of family 36 in the classification of glycosyl hydrolases. the enzyme was estimated to be a tetramer with a molecular mass of subunits 80.3 kda. the purified agan is thermostable and has a temperature optimum of activity at 75 degrees c ... | 1999 | 10418141 |
| organophosphorus acid anhydrolase in slime mold, duckweed and mung bean: a continuing search for a physiological role and a natural substrate. | recently, and for the first time, a diisopropylphosphorofluoridate (dfp)-hydrolyzing enzyme, i.e. an organophosphorus acid anhydrolase (opaa), has been reported in a plant-source. based on this and other suggestive evidence, the ability of three plant sources and a protist to hydrolyze dfp and 1,2,2-trimethylpropyl methylphosphonofluoridate (soman) were tested, and the effects of mn2+ and ethylenediamine tetraacetate (edta) on this activity. the plants are duckweed (lemna minor), giant duckweed ... | 1999 | 10421476 |
| establishing the independent culture of a strictly symbiotic bacterium symbiobacterium thermophilum from its supporting bacillus strain. | symbiobacterium thermophilum is a strictly symbiotic thermophile, the growth of which is dependent on the coexistence of an associating thermophilic bacillus sp., strain s. s. thermophilum grows only in mixed culture with the bacillus strain in liquid media, and does not form visible colonies on solid media. to measure the growth of this symbiotic bacterium and to analyze its growth requirements, we developed a quantitative pcr method by using its specific sequences in a putative membrane transl ... | 1999 | 10427695 |
| structural studies of the bstvi restriction-modification proteins by fluorescence spectroscopy. | structural studies of the proteins of the bstvi restriction-modification system of bacillus stearothermophilus v were carried out using intrinsic fluorescence techniques. the exposure and environments of their tryptophanyl residues were determined using collisional quenchers. quenching of bstvi endonuclease by iodide suggested a heterogeneous class of tryptophan residues, while the results obtained with m.bstvi methylase were consistent with a rather exposed tryptophan population. a comparison o ... | 1999 | 10429188 |
| sporicidal activity of a new low-temperature sterilization technology: the sterrad 50 sterilizer. | this study was undertaken to evaluate the efficacy of a new low-temperature sterilization system that recently has been cleared by the food and drug administration, the sterrad 50. flat stainless steel carriers were inoculated with approximately 10(6) bacillus stearothermophilus spores. these carriers were placed aseptically in the middle of 40-cm-long stainless steel-lumened test units of varying diameters (1 mm, 2 mm, and 3 mm). after inoculation, the test units were processed in the sterrad 5 ... | 1999 | 10432166 |
| the diacetamidodideoxyuronic-acid-containing glycan chain of bacillus stearothermophilus nrs 2004/3a represents the secondary cell-wall polymer of wild-type b. stearothermophilus strains. | the diacetamidodideoxymannuronic-acid-containing glycan of bacillus stearothermophilus nrs 2004/3a with the repeating unit structure [-->4)-beta-d-manpa2,3(nac)2-(1-->6)-alpha-d-glcp-(1-->4)-beta-d-+ ++manpa2,3 (nac)2-(1-->3)-alpha-d-glcpnac-(1-->], was examined to identify its linkage to the bacterial cell wall. in a previous paper it was suggested that this glycan is covalently linked to the surface layer (s-layer) glycoprotein of that organism. by improved chromatographic techniques (gel perm ... | 1999 | 10439396 |
| production of alpha-amylase in fed-batch cultures of vgb+ and vgb- recombinant escherichia coli: some observations. | synthesis and excretion of bacillus stearothermophilus alpha-amylase is analyzed in fed-batch cultivations of escherichia coli jm103[pmk79] and e. coli jm103[pmk57], the former strain containing the plasmid-encoded vitreoscilla hemoglobin (vhb) gene (vgb) and the latter strain being devoid of this gene. fed-batch operation is observed to be substantially superior to batch operation as concerns the alpha-amylase production rate and the extent of excretion of the enzyme. faster feeding of a nutrie ... | 1999 | 10441355 |
| thermal unfolding of phosphorylating d-glyceraldehyde-3-phosphate dehydrogenase studied by differential scanning calorimetry. | thermal unfolding parameters were determined for a two-domain tetrameric enzyme, phosphorylating d-glyceraldehyde-3-phosphate dehydrogenase (gapdh), and for its isolated nad(+)-binding domain. at ph 8.0, the transition temperatures (t(max)) for the apoforms of the native bacillus stearothermophilus gapdh and the isolated domain were 78.3 degrees c and 61.9 degrees c, with calorimetric enthalpies (deltah(cal)) of 4415 and 437 kj/mol (or 30.7 and 22.1 j/g), respectively. in the presence of nearly ... | 1999 | 10446379 |
| mutational analysis of the thermostable arginine repressor from bacillus stearothermophilus: dissecting residues involved in dna binding properties. | recently the crystal structure of the dna-unbound form of the full-length hexameric bacillus stearothermophilus arginine repressor (argr) has been resolved, providing a possible explanation for the mechanism of arginine-mediated repressor-operator dna recognition. in this study we tested some of these functional predictions by performing site-directed mutagenesis of distinct amino acid residues located in two regions, the n-terminal dna-binding domain and the c-terminal oligomerization domain of ... | 1999 | 10452892 |
| thermal inactivation kinetics of bacillus stearothermophilus spores using a linear temperature program. | a systematic study of the inactivation kinetics of bacillus stearothermophilus spores was carried out in nonisothermic heating conditions using a linear temperature increase program and analyzing the experimental data by means of a one-step nonlinear regression. the d and z values estimated are close to those obtained in isothermic conditions and estimated by using a two-step model, first d values are calculated, and then in the second step a z value is deduced (d(121 degrees c) = 3.08 and 4.38 ... | 1999 | 10456754 |
| characterization of a novel stable biocatalyst obtained by protein engineering. | protein engineering is a powerful tool for the improvement of the properties of biocatalysts. previously we have applied protein engineering technologies to obtain an extremely stable variant of the thermolysin-like protease from bacillus stearothermophilus [van den burg, vriend, veltman, venema and eijsink (1998) proc. natl. acad. sci. u.s.a. 95, 2056-2060]. this variant is much more resistant to denaturing conditions (temperature and denaturing agents) than the wild-type enzyme. an extensive e ... | 1999 | 10467116 |
| protein design of geranyl diphosphate synthase. structural features that define the product specificities of prenyltransferases. | geranyl diphosphate synthase catalyzes the condensation of isopentenyl diphosphate with dimethylallyl diphosphate to give a c(10) compound, geranyl diphosphate, which is a precursor of all monoterpenoids. however, the gene has not been isolated from any organisms. to examine the possibility that geranyl diphosphate synthase has evolved from a common ancestor of the prenyltransferase family and to predict the active site structure, we tried to convert bacillus stearothermophilus farnesyl diphosph ... | 1999 | 10467173 |
| identification of a virulence-associated protein homolog gene and isra1 in a plasmid of riemerella anatipestifer. | riemerella anatipestifer is the causative agent of polyserositis of ducks and geese. we have previously reported that a 3.9-kb plasmid, pcfc1, carries protein genes (vapd1 and vapd2) that are similar to virulence-associated genes of other bacteria. in the present study, we report the complete sequence of a second plasmid of 5.6 kb, pcfc2. pcfc2 has a 28% g-c content and three large open reading frames (orfs). one of the orfs (designated asvapd1) encodes a polypeptide that shares 53.9, 53.9, 48.3 ... | 1999 | 10481080 |
| the electric dipole moment of dna-binding hu protein calculated by the use of an nmr database. | electric birefringence measurements indicated the presence of a large permanent dipole moment in hu protein-dna complex. in order to substantiate this observation, numerical computation of the dipole moment of hu protein homodimer was carried out by using nmr protein databases. the dipole moments of globular proteins have hitherto been calculated with x-ray databases and nmr data have never been used before. the advantages of nmr databases are: (a) nmr data are obtained, unlike x-ray databases, ... | 1999 | 10483709 |
| functional characterization of the phosphorylating d-glyceraldehyde 3-phosphate dehydrogenase from the archaeon methanothermus fervidus by comparative molecular modelling and site-directed mutagenesis. | phosphorylating archaeal d-glyceraldehyde 3-phosphate dehydrogenases (grap-dhs) share only 15-20% identity with their glycolytic bacterial and eukaryotic counterparts. unlike the latter which are nad-specific, archaeal grap-dhs exhibit a dual-cofactor specificity with a marked preference for nadp. in the present study, we have constructed a three-dimensional model of the methanothermus fervidus grap-dh based upon the x-ray structures of the bacillus stearothermophilus and escherichia coli grap-d ... | 1999 | 10491162 |
| refining the overall structure and subdomain orientation of ribosomal protein s4 delta41 with dipolar couplings measured by nmr in uniaxial liquid crystalline phases. | prokaryotic protein s4 initiates assembly of the small ribosomal subunit by binding to 16 s rrna. residues 43-200 of s4 from bacillus stearothermophilus (s4 delta41) bind to both 16 s rrna and to a mrna pseudoknot. in order to obtain structure-based insights regarding rna binding, we previously determined the solution structure of s4 delta41 using noe, hydrogen bond, and torsion angle restraints. s4 delta41 is elongated, with two distinct subdomains, one all helical, the other including a beta-s ... | 1999 | 10493882 |
| tyrosine 265 of alanine racemase serves as a base abstracting alpha-hydrogen from l-alanine: the counterpart residue to lysine 39 specific to d-alanine. | alanine racemase of bacillus stearothermophilus has been proposed to catalyze alanine racemization by means of two catalytic bases: lysine 39 (k39) abstracting specifically the alpha-hydrogen of d-alanine and tyrosine 265 (y265) playing the corresponding role for the antipode l-alanine. the role of k39 as indicated has already been verified [watanabe, a., kurokawa, y., yoshimura, t., kurihara, t., soda, k., and esaki, n. (1999) j. biol. chem. 274, 4189-4194]. we here present evidence for the fun ... | 1999 | 10502689 |
| bacterial cell envelopes (ghosts) but not s-layers activate human endothelial cells (huvecs) through scd14 and lbp mechanism. | bacterial cell-envelopes (called ghosts) and surface layers (s-layers) are discussed to be used as vaccines and/or adjuvants, consequently it is necessary to find out which immunomodulatory mediators are induced in human cells. the present work focuses on the effects of ghosts (escherichia coli o26:b6), s-layers (bacillus stearothermophilus) in comparison with lps and antibiotic-inactivated whole bacteria (e. coli o26:b6) on human umbilical vein endothelial cells (huvec) with regard to the relea ... | 1999 | 10519933 |
| the fmet-trna binding domain of translational initiation factor if2: role and environment of its two cys residues. | mutations of the cysteines (positions 668 and 714) were generated in the if2 c domain of bacillus stearothermophilus translation initiation factor if2. the corresponding proteins were characterized functionally and structurally. most (yet not all) amino acid replacements at both positions resulted in severe reduction of the fmet-trna binding activity of if2 c without grossly altering its structure. our work demonstrates that: (a) both cys residues are buried within an hydrophobic core and not ac ... | 1999 | 10526160 |
| phosphorylation of ribosomal protein l18 is required for its folding and binding to 5s rrna. | ribosomal protein l18 from bacillus stearothermophilus (bl18) includes a previously unreported phosphoserine residue. the folded conformation of the protein is stabilized by the dianionic form of the phosphate group of that residue. in the absence of mg2+, the pk(a) of the phosphate group is so high that the protein is not fully folded at ph 7. in the presence of mg2+, its pk(a) drops significantly, and consequently the native conformation of bl18 becomes stable at ph 7 and the protein is able t ... | 1999 | 10529214 |
| identification by subtractive hybridization of a novel insertion sequence specific for virulent strains of porphyromonas gingivalis. | subtractive hybridization was employed to isolate specific genes from virulent porphyromonas gingivalis strains that are possibly related to abscess formation. the genomic dna from the virulent strain p. gingivalis w83 was subtracted with dna from the avirulent strain atcc 33277. three clones unique to strain w83 were isolated and sequenced. the cloned dna fragments were 885, 369, and 132 bp and had slight homology with only bacillus stearothermophilus is5377, which is a putative transposase. th ... | 1999 | 10531208 |
| structure of ribosomal protein l30 from thermus thermophilus at 1.9 a resolution: conformational flexibility of the molecule. | the crystal structure of ribosomal protein l30 from the extreme thermophilic bacterium thermus thermophilus has been determined at 1. 9 a resolution. the crystals are trigonal and belong to space group p3(2)21, with unit-cell parameters a = b = 63.5, c = 77.8 a, alpha = beta = 90, gamma = 120 degrees and two molecules per asymmetric unit. the structure was solved by the molecular-replacement method with amore and refined with x-plor to an r value of 20.3% and an r(free) of 25.3% in the resolutio ... | 1999 | 10531479 |
| crystallization and preliminary x-ray diffraction analysis of the homodimeric form alpha2 of the hu protein from escherichia coli. | the homodimeric form alpha(2) of the escherichia coli dna-binding protein hu was crystallized by the hanging-drop vapour-diffusion method using peg 4000 as a precipitant. the crystals belong to space group i222, with unit-cell parameters a = 31.09, b = 55.34, c = 117. 63 a, and contain one monomer per asymmetric unit. a full diffraction data set was collected to 2.3 a resolution on a conventional x-ray source. the molecular-replacement method, using the hu crystallographic model from bacillus st ... | 1999 | 10531506 |
| site-directed mutagenesis of the conserved residues in component i of bacillus subtilis heptaprenyl diphosphate synthase. | heptaprenyl diphosphate synthase of bacillus subtilis is composed of two dissociable heteromeric subunits, component i and component ii. component ii has highly conserved regions typical of (e)-prenyl diphosphate synthases, but it shows no prenyltransferase activity alone unless it is combined with component i. alignment of amino acid sequences for component i and the corresponding subunits of bacillus stearothermophilus heptaprenyl diphosphate synthase and micrococcus luteus b-p 26 hexaprenyl d ... | 1999 | 10545188 |
| comparative study of the inhibition of alpha-glucosidase, alpha-amylase, and cyclomaltodextrin glucanosyltransferase by acarbose, isoacarbose, and acarviosine-glucose. | bacillus stearothermophilus maltogenic amylase hydrolyzes the first glycosidic linkage of acarbose to give acarviosine-glucose. in the presence of carbohydrate acceptors, acarviosine-glucose is primarily transferred to the c-6 position of the acceptor. when d-glucose is the acceptor, isoacarbose is formed. acarbose, acarviosine-glucose, and isoacarbose were compared as inhibitors of alpha-glucosidase, alpha-amylase, and cyclomaltodextrin glucanosyltransferase. the three inhibitors were found to ... | 1999 | 10545215 |
| transglycosylation of naringin by bacillus stearothermophilusmaltogenic amylase to give glycosylated naringin. | naringin, a bitter compound in citrus fruits, was transglycosylated by bacillus stearothermophilus maltogenic amylase reaction with maltotriose to give a series of mono-, di-, and triglycosylnaringins. glycosylation products of naringin were observed by tlc and hplc. the major glycosylation product was purified by using a sephadex lh-20 column. the sturcture was determined by using maldi-tof ms, methylation analysis, and (1)h and (13)c nmr. the major transglycosylation product was maltosylnaring ... | 1999 | 10552702 |
| phosphorylated aspartate in the structure of a response regulator protein. | phosphorylation of aspartic acid residues is the hallmark of two- component signal transduction systems that orchestrate the adaptive responses of micro-organisms to changes in their surroundings. two-component systems consist of a sensor kinase that interprets environmental signals and a response regulator that activates the appropriate physiological response. although structures of response regulators are known, little is understood about their activated phosphorylated forms, due to the intrin ... | 1999 | 10556024 |
| redesign of the coenzyme specificity in l-lactate dehydrogenase from bacillus stearothermophilus using site-directed mutagenesis and media engineering. | l-lactate dehydrogenase (ldh) from bacillus stearothermophilus is a redox enzyme which has a strong preference for nadh over nadph as coenzyme. to exclude nadph from the coenzyme-binding pocket, ldh contains a conserved aspartate residue at position 52. however, this residue is probably not solely responsible for the nadh specificity. in this report we examine the possibilities of altering the coenzyme specificity of ldh by introducing a range of different point mutations in the coenzyme-binding ... | 1999 | 10556245 |
| role of the n-terminal region of ribosomal protein s7 in its interaction with 16s rrna which binds to the concavity formed by the beta-ribbon arm and the alpha-helix. | the ribosomal protein s7, a primary 16s rrna-binding protein, plays an essential role in stabilizing the 3' major domain of 16s rrna and also in feedback regulation of the str operon, as a translational repressor. we examined amino acid residues in ribosomal protein s7 from bacillus stearothermophilus (bsts7) that are essential for 16s rrna binding. truncation of the n-terminal 10 residues of bsts7 abolished its binding to 16s rrna, whereas removal of the c-terminal eight residues had no effect ... | 1999 | 10561602 |