Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| chloride affects the interaction between tyrosyl-trna synthetase and trna. | the physiological concentration of free magnesium in escherichia coli cells is about 1 mm, and there is almost no chloride in the cell. when the aminoacylation of trna by tyrosyl-trna synthetase was assayed at 1 mm free mg2+, chloride (and sulphate) ions inhibited the reaction but acetate at the same concentration (< 200 mm) was not inhibitory. when the magnesium concentration was increased to 10 mm there was almost no chloride inhibition any more. chloride strengthened the ppi inhibition, the k ... | 1999 | 10572925 |
| self-assembly and catalytic activity of the pyruvate dehydrogenase multienzyme complex from bacillus stearothermophilus. | the pyruvate dehydrogenase multienzyme complex from bacillus stearothermophilus was reconstituted in vitro from recombinant proteins derived from genes over-expressed in escherichia coli. titrations of the icosahedral (60-mer) dihydrolipoyl acetyltransferase (e2) core component with the pyruvate decarboxylase (e1, alpha2beta2) and dihydrolipoyl dehydrogenase (e3, alpha2) peripheral components indicated a variable composition defined predominantly by tight and mutually exclusive binding of e1 and ... | 1999 | 10583411 |
| biochemical and phylogenetic analyses of a cold-active beta-galactosidase from the lactic acid bacterium carnobacterium piscicola ba. | we are investigating glycosyl hydrolases from new psychrophilic isolates to examine the adaptations of enzymes to low temperatures. a beta-galactosidase from isolate ba, which we have classified as a strain of the lactic acid bacterium carnobacterium piscicola, was capable of hydrolyzing the chromogen 5-bromo-4-chloro-3-indolyl beta-d-galactopyranoside (x-gal) at 4 degrees c and possessed higher activity in crude cell lysates at 25 than at 37 degrees c. sequence analysis of a cloned dna fragment ... | 1999 | 10584002 |
| three domains comprised in thermostable molecular weight 54,000 pullulanase of type i from bacillus flavocaldarius kp1228. | the gene that coded for a cellular pullulanase of type i (alpha-dextrin 6-glucanohydrolase, ec 3.2.1.41) in bacillus flavocaldarius kp1228 (ferm-p9542) cells growing at 51 to 82 degrees c was expressed in escherichia coli mv1184. the enzyme had a half-life of 10 min at 107 degrees c. purification of the enzyme and its characterization showed that the enzyme was identical with the native one. its primary structure of 475 residues with a molecular weight of 53,856 deduced from the gene was 15-21% ... | 1999 | 10586502 |
| dimers generated from tetrameric phosphorylating glyceraldehyde-3-phosphate dehydrogenase from bacillus stearothermophilus are inactive but exhibit cooperativity in nad binding. | tetrameric phosphorylating glyceraldehyde-3-phosphate dehydrogenase (gapdh) from bacillus stearothermophilus has been described as a "dimer of dimers" with three nonequivalent interfaces, p-axis (between subunits o and p and between subunits q and r), q-axis (between subunits o and q and between subunits p and r), and r-axis interface (between subunits o and r and between subunits p and q). o-p dimers, the most stable and the easiest to generate, have been created by selective disruption of hydr ... | 1999 | 10587431 |
| a conserved serine-rich stretch in the glutamate transporter family forms a substrate-sensitive reentrant loop. | neuronal and glial glutamate transporters remove the excitatory neurotransmitter glutamate from the synaptic cleft. the proteins belong to a large family of secondary transporters, which includes bacterial glutamate transporters. the c-terminal half of the glutamate transporters is well conserved and thought to contain the translocation path and the binding sites for substrate and coupling ions. a serine-rich sequence motif in this part of the proteins is located in a putative intracellular loop ... | 1999 | 10588697 |
| nucleotide sequence of the gene encoding the bstlvi dna methyltransferase: comparison with other amino-dna methyltransferases. | the nucleotide sequence of a 2837-base pairs (bp) ecori-pvui fragment of bacillus stearothermophilus lv chromosomal dna encoding the bstlvim gene was determined. it revealed a large open reading frame (orf) of 1737 bp specifying a methylase of 579 amino acid (aa) residues and mr 66,831. this was in agreement with the size estimated for the m. bstlvi ( approximately 67 kda) purified from escherichia coli cells harboring a recombinant plasmid containing the bstlvim gene and with results of transcr ... | 2000 | 10594225 |
| probing the location and function of the conserved histidine residue of phosphoglucose isomerase by using an active site directed inhibitor n-bromoacetylethanolamine phosphate. | phosphoglucose isomerase (ec 5.3.1.9) catalyzes the interconversion of d-glucopyranose-6-phosphate and d-fructofuranose-6-phosphate by promoting an intrahydrogen transfer between c1 and c2. a conserved histidine exists throughout all phosphoglucose isomerases and was hypothesized to be the base catalyzing the isomerization reaction. in the present study, this conserved histidine, his311, of the enzyme from bacillus stearothermophilus was subjected to mutational analysis, and the mutational effec ... | 1999 | 10595547 |
| over-expression of cbaab genes of bacillus stearothermophilus produces a two-subunit soxb-type cytochrome c oxidase with proton pumping activity. | we constructed expression plasmids containing cbaab, the structural genes for the two-subunit cytochrome bo(3)-type cytochrome c oxidase (soxb type) recently isolated from a gram-positive thermophile bacillus stearothermophilus. b. stearothermophilus cells transformed with the plasmids over-expressed an enzymatically active bo(3)-type cytochrome c oxidase protein composed of the two subunits, while the transformed escherichia coli cells produced an inactive protein composed of subunit i without ... | 2000 | 10611454 |
| mapping protein-protein interactions within a stable complex of dna primase and dnab helicase from bacillus stearothermophilus. | for the first time, we demonstrate directly a stable complex between a bacterial dnag (primase) and dnab (helicase). utilizing fragments of both proteins, we are able to dissect interactions within this complex and provide direct evidence that it is the c-terminal domain of primase that interacts with dnab. furthermore, this c-terminal domain is sufficient to induce maximal stimulation of the helicase and atpase activities of dnab. however, the region of dnab that interacts with the c-terminal d ... | 2000 | 10625492 |
| intersubunit location of the active site of farnesyl diphosphate synthase: reconstruction of active enzymes by hybrid-type heteromeric dimers of site-directed mutants. | farnesyl diphosphate synthase is a homodimer of subunits having typically two aspartate-rich motifs with two sets of substrate binding sites for an allylic diphosphate and isopentenyl diphosphate per molecule of a homodimeric enzyme. to determine whether each subunit contains an independent active site or whether the active sites are created by intersubunit interaction, we constructed several expression plasmids that overproduce hybrid-type heterodimers of bacillus stearothermophilus fpp synthas ... | 2000 | 10631008 |
| s-layer-coated liposomes as a versatile system for entrapping and binding target molecules. | in the present study, unilamellar liposomes coated with the crystalline bacterial cell surface layer (s-layer) protein of bacillus stearothermophilus pv72/p2 were used as matrix for defined binding of functional molecules via the avidin- or streptavidin-biotin bridge. the liposomes were composed of dipalmitoyl phosphatidylcholine, cholesterol and hexadecylamine in a molar ratio of 10:5:4 and they had an average size of 180 nm. for introducing specific functions into the s-layer lattice without a ... | 2000 | 10631303 |
| molecular recognition of tyrosinyl adenylate analogues by prokaryotic tyrosyl trna synthetases. | molecular modelling and synthetic studies have been carried out on tyrosinyl adenylate and analogues to probe the interactions seen in the active site of the x-ray crystal structure of tyrosyl trna synthetase from bacillus stearothermophilus, and to search for new inhibitors of this enzyme. micromolar and sub-micromolar inhibitors of tyrosyl trna synthetases from both b. stearothermophilus and staphylococcus aureus have been synthesised. the importance of the adenine ring to the binding of tyros ... | 1999 | 10632057 |
| bacillus stearothermophilus lctb gene gives rise to functional k+ channels in escherichia coli and in xenopus oocytes. | we have cloned a small k+ channel subunit (lctb) of the gram-positive bacterium bacillus stearothermophilus (b. stearo.). the b. stearo. lctb protein is only 134 amino acids long. the sequence contains a typical k+ channel p-domain with a k+ channel gygd signature sequence and two hydrophobic, possibly membrane-spanning segments m1 and m2. unexpectedly, lctb k+ channels exhibited properties which differed markedly from the ones reported for kcsa channels of the gram-positive bacterium streptomyc ... | 1999 | 10635064 |
| towards regioselective synthesis of oligosaccharides by use of alpha-glucosidases with different substrate specificity. | alpha-glucosidase from two microbial sources, bacillus stearothermophilus and brewer's yeast, has been used to catalyze transglycosylation reactions and a comparative study was carried out to determine the regioselectivity of this reaction. bacterial alpha-glucosidase exhibited higher transfer activity with maltose and was able to synthesize tri- and tetrasaccharides in high yield (27%). in the case of yeast enzyme, only trisaccharides were synthesized in lower yield. structure analysis of trans ... | 1999 | 10637985 |
| the c-terminal subdomain (if2 c-2) contains the entire fmet-trna binding site of initiation factor if2. | previous protein unfolding studies had suggested that if2 c, the 24. 5-kda fmet-trna binding domain of bacillus stearothermophilus translation initiation factor if2, may consist of two subdomains. in the present work, the four phe residues of if2 c (positions 531, 599, 657, and 721) were replaced with trp, yielding four variant proteins having intrinsic fluorescence markers in different positions of the molecule. comparison of the circular dichroism and trp fluorescence changes induced by increa ... | 2000 | 10644698 |
| altered regulation of pyruvate kinase or co-overexpression of phosphofructokinase increases glycolytic fluxes in resting escherichia coli. | glycolytic fluxes in resting escherichia coli were enhanced by overexpression of heterologous pyruvate kinases (pyk) from bacillus stearothermophilus and zymomonas mobilis, but not homologous pyk. compared to the control, an increase of 10% in specific glucose consumption and of 15% in specific ethanol production rates was found in anaerobic resting cells, expressing the heterologous pyks, that were harvested from exponentially growing aerobic cultures. a further increase in glycolytic flux was ... | 2000 | 10649237 |
| protein-protein interaction revealed by nmr t(2) relaxation experiments: the lipoyl domain and e1 component of the pyruvate dehydrogenase multienzyme complex of bacillus stearothermophilus. | t(2) relaxation experiments in combination with chemical shift and site-directed mutagenesis data were used to identify sites involved in weak but specific protein-protein interactions in the pyruvate dehydrogenase multienzyme complex of bacillus stearothermophilus. the pyruvate decarboxylase component, a heterotetramer e1(alpha(2)beta(2)), is responsible for the first committed and irreversible catalytic step. the accompanying reductive acetylation of the lipoyl group attached to the dihydrolip ... | 2000 | 10656808 |
| catabolite repression of the xylanase gene (xyna) expression in bacillus stearothermophilus no. 236 and b. subtilis. | catabolite repression of the bacillus stearothermophilus no. 236 xyna gene, encoding an extracellular xylanase, was investigated in this work. expression of the xyna gene in the b. stearothermophilus strain was found to be subject to glucose catabolite repression, and the level of repression was about 50-fold when the relative amounts of xyna transcript synthesized on different carbon sources were analyzed. the experiments with the b. subtilis mw15 strains carrying plasmids containing the xyna:: ... | 1999 | 10664837 |
| arginine-55 in the beta-arm is essential for the activity of dna-binding protein hu from bacillus stearothermophilus. | dna-binding protein hu (bsthu) from bacillus stearothermophilus is a homodimeric protein which binds to dna in a sequence-nonspecific manner. in order to identify the arg residues essential for dna binding, four arg residues (arg-53, arg-55, arg-58, and arg-61) within the beta-arm structure were replaced either by gln, lys, or glu residues, and the resulting mutants were characterized with respect to their dna-binding activity by a filter-binding analysis and surface plasmon resonance analysis. ... | 1999 | 10664859 |
| crystallization and preliminary x-ray analysis of an intracellular xylanase from bacillus stearothermophilus t-6. | xylanases (1,4-beta-d-xylan xylanhydrolases; e.c. 3.2.1.8) hydrolyze the 1,4-beta-d-xylopyranosyl linkage of xylans. the structural characterization of xylanase active sites is of great interest, since it can lead to a better understanding of their catalytic mechanism and contribute significant knowledge to the rational design of specific oligosaccharide-binding sites via protein engineering. an intracellular xylanase gene (xyna2) from bacillus stearothermophilus t-6 has recently been cloned and ... | 2000 | 10666598 |
| purification, crystallization and preliminary x-ray crystallographic study of alpha-amylase from bacillus stearothermophilus. | a recombinant alpha-amylase from bacillus stearothermophilus was found to be produced as several isoforms arising from different n--terminal processing. some of those isoforms were purified to homogeneity and crystallized at 293 k using the hanging-drop vapour-diffusion method under the following conditions: 35 mm sodium acetate (ph 4.6), 6.25%(v/v) 2-propanol, in the presence of 1.23%(w/v) acarbose (a pseudo-oligosaccharide inhibitor) in the drop. the crystals diffracted beyond 2.0 a resolution ... | 2000 | 10666605 |
| purification and properties of genetic expressing product of thermostable protease from bacillus stearothermophilus hy-69. | the thermostable metal protease gene from bacillus stearothermophilus hy-69 had been cloned and expressed in bacillus subtilis mi113. the genetic expressing product of the enzyme was purified by cm-cellulose chromatography. the product shows homogeneity on page. its molecular weight is 27,000 +/- 1000 by sds-page and sephadex g100 filtration, respectively. the alpha-helix content of the protease is estimated to be about 66%, the beta-turn about 28%, the random coil about 6%, but not beta-sheet, ... | 1999 | 10668130 |
| the anticodon-binding domain of tyrosyl-trna synthetase: state of folding and origin of the crystallographic disorder. | the c-terminal domain (residues 320-419) of tyrosyl-trna synthetase (tyrrs) from bacillus stearothermophilus is disordered in the crystal structure. its function consists of binding the anticodon of trna(tyr). we undertook to characterize its conformational state. a hybrid between the c-terminal fragment and a his-tag sequence was constructed and purified in large amounts. analyses by mass spectrometry and analytical ultracentrifugation showed that the c-terminal fragment, thus purified, was not ... | 2000 | 10677223 |
| production of an activated form of bacillus stearothermophilus l-2-hydroxyacid dehydrogenase by directed evolution. | bacillus stearothermophillus lactate dehydrogenase (bsldh) is activated in the presence of fructose 1,6 bisphosphate (fbp). the activator is expensive and representative of the sort of co-factor complications that are undesirable in industrial processes. three rounds of random mutagenesis and screening produced a mutant (6a) which is almost fully activated in the absence of fbp. wild-type bsldh has a k(pyr)(m) of 5 mm in the absence of fbp but when activated (+fbp) the k(pyr)(m) drops to 0.05 mm ... | 2000 | 10679523 |
| mapping posttranscriptional modifications in 5s ribosomal rna by maldi mass spectrometry. | we present a method to screen rna for posttranscriptional modifications based on matrix assisted laser desorption/ionization mass spectrometry (maldi-ms). after the rna is digested to completion with a nucleotide-specific rnase, the fragments are analyzed by mass spectrometry. a comparison of the observed mass data with the data predicted from the gene sequence identifies fragments harboring modified nucleotides. fragments larger than dinucleotides were valuable for the identification of posttra ... | 2000 | 10688367 |
| cloning of a wide-spectrum amidase from bacillus stearothermophilus br388 in escherichia coli and marked enhancement of amidase expression using directed evolution* | a 1.6-kb drai-hindiii dna fragment from bacillus stearothermophilus br388 chromosomal dna encoding a wide-spectrum amidase was cloned into escherichia coli dh5alpha. with acrylamide substrate, the amidase showed maximum activity at 55 degrees c, ph 7.0, and 0.12-m substrate, and demonstrated significant activity in 1-m acrylamide. a mutant prepared by pcr-based random mutagenesis of a 1.65 kb segment of b. stearothermophilus br388 chromosomal dna containing the amidase gene had two adenine bases ... | 2000 | 10689071 |
| transglycosylation of neohesperidin dihydrochalcone by bacillus stearothermophilus maltogenic amylase. | neohesperidin dihydrochalcone (nhdc), a sweet compound derived from citrus fruits, was modified to a series of its oligosaccharides by transglycosylation activity of bacillus stearothermophilus maltogenic amylase (bsma). maltotriose as a donor was reacted with nhdc as an acceptor to glycosylate for the purpose of increasing the solubility of nhdc. maltosyl-nhdc was a major transglycosylation product among the several transfer products by tlc analysis. the structure of the major transglycosylatio ... | 2000 | 10691608 |
| multiple phosphorylation events regulate the activity of the mannitol transcriptional regulator mtlr of the bacillus stearothermophilus phosphoenolpyruvate-dependent mannitol phosphotransferase system. | d-mannitol is taken up by bacillus stearothermophilus and phosphorylated via a phosphoenolpyruvate-dependent phosphotransferase system (pts). transcription of the genes involved in mannitol uptake in this bacterium is regulated by the transcriptional regulator mtlr, a dna-binding protein whose affinity for dna is controlled by phosphorylation by the pts proteins hpr and iicb(mtl). the mutational and biochemical studies presented in this report reveal that two domains of mtlr, pts regulation doma ... | 2000 | 10702268 |
| overproduction and characterization of seleno-methionine xylanase t-6. | the extracellular xylanase from bacillus stearothermophilus t-6 is a thermostable alkaline tolerant enzyme that was found to bleach pulp optimally at ph 9 and 65 degrees c, and was successfully used in a large-scale bio-bleaching mill trial. in an attempt to obtain a heavy atom derivative suitable for complete x-ray analysis, xylanase t-6 was labeled biosynthetically with seleno-methionine, resulting in a 'built-in' array of atoms with specific x-ray anomalous scattering signal. optimization of ... | 2000 | 10702913 |
| s-layer gene sbsc of bacillus stearothermophilus atcc 12980: molecular characterization and heterologous expression in escherichia coli. | the cell surface of bacillus stearothermophilus atcc 12980 is completely covered with an oblique s-layer lattice. to investigate sequence identities and a common structure-function relationship in s-layer proteins of different b. stearothermophilus wild-type strains, the nucleotide sequence encoding the s-layer protein sbsc of b. stearothermophilus atcc 12980 was determined by pcr techniques. the entire sbsc sequence showed an orf of 3297 bp predicted to encode a protein of 1099 aa with a theore ... | 2000 | 10708365 |
| preparation of thermus thermophilus holo-chaperonin-immobilized microspheres with high ability to facilitate protein refolding. | carboxylated poly(styrene/acrylamide) (p(st/aam)-h) microspheres with different acrylamide contents were prepared by emulsifier-free emulsion polymerization. thermus thermophilus holo-chaperonin (cpn) was covalently immobilized onto these microspheres with high yield. the t. thermophilus holo-cpn-immobilized microspheres were used for refolding of guanidine hydrochloride (gdn-hcl)-denatured enzymes and showed sufficiently high ability to facilitate refolding of leuconostoc mesenteroides glucose- ... | 2000 | 10712734 |
| domain swapping in the sporulation response regulator spo0a. | adaptive responses of micro-organisms, such as chemotaxis and sporulation, are governed by two-component systems consisting of sensor kinases, that interpret environmental signals, and response regulators which activate the appropriate physiological responses. signal transduction via response regulator proteins is mediated through transient phosphorylation of aspartic acid residues. in spo0a, the key regulator of development (sporulation) in bacillus, phosphorylation of the n-terminal receiver d ... | 2000 | 10731426 |
| the pyrab gene coding for the large subunit of carbamoylphosphate synthetase from bacillus stearothermophilus: molecular cloning and functional characterization. | the bacillus stearothermophilus pyrab gene, encoding the large subunit of carbamoylphosphate synthetase, was isolated and characterized. the dna sequence is a 3195-nucleotide long reading frame coding for a polypeptide of 1064 amino acids and deduced mr approximately 116,160 da. the pyrab gene is part of the b. stearothermophilus pyrimidine biosynthesis operon pyr. the 5' end of thepyrab gene overlaps with the 3' end of the pyraa gene coding for the small subunit of carbamoylphosphate synthetase ... | 1998 | 10732707 |
| effect of acidification and oil on the thermal resistance of bacillus stearothermophilus spores heated in food substrate. | the effect of the addition of vinegar and/or oil to a food homogenate (tomato sauce, tuna and vegetables) on the thermal resistance of bacillus stearothermophilus spores was studied. the results indicated that the food substrate without the addition of vinegar and oil and a ph value of 5.28 reduced the thermal resistance of b. stearothermophilus spores compared with that obtained in double-distilled water, (d121 = 1.41 and 3.08 min respectively). the addition of vinegar reduced the ph of the sub ... | 1999 | 10733251 |
| thermostable lipase of bacillus stearothermophilus: high-level production, purification, and calcium-dependent thermostability. | an efficient expression system was developed for the production of the thermostable lipase from bacillus stearothermophilus l1 in an escherichia coli system. a structural gene corresponding to mature lipase was subcloned in the pet-22b(+) expression vector and its expression was induced by iptg at 30 degrees c in e. coli cells. the lipase activity in a cell-free extract was as high as 448,000 units/g protein, which corresponds to as much as 26% of the total cellular protein and is 77 times highe ... | 2000 | 10737182 |
| lysyl-trna synthetase of bacillus stearothermophilus molecular cloning and expression of the gene. | the gene of the lysyl-trna synthetase of bacillus stearothermophilus nca1503 was cloned and sequenced. the gene consists of 1485 bp nucleotides commencing with an atg start codon and ending with a taa stop codon, and encodes a polypeptide of 493 amino acids. the recombinant enzymes were expressed in e. coli using an expression plasmid containing the t7 rna polymerase/promoter. | 2000 | 10737207 |
| energy-yielding properties of soxb-type cytochrome bo(3) terminal oxidase: analyses involving bacillus stearothermophilus k1041 and its mutant strains. | we isolated a k17q8 mutant from k17 mutant cells of bacillus stearothermophilus which contain soxb-type cytochrome bo(3) as well as cytochrome bd but not soxm-type cytochrome caa(3), which is the main terminal oxidase in b. stearothermophilus k1041. the respiration of k17q8 was highly sensitive to as little as 10 microm cyanide, indicating that the main terminal oxidase is cytochrome bo(3). the aerobic growth yield of k17q8 was lower than that of wild-type k1041, but higher than that of parental ... | 2000 | 10739945 |
| structure of the zinc-binding domain of bacillus stearothermophilus dna primase. | dna primases catalyse the synthesis of the short rna primers that are required for dna replication by dna polymerases. primases comprise three functional domains: a zinc-binding domain that is responsible for template recognition, a polymerase domain, and a domain that interacts with the replicative helicase, dnab. | 2000 | 10745010 |
| structure and mechanism of action of a novel phosphoglycerate mutase from bacillus stearothermophilus. | bacillus stearothermophilus phosphoglycerate mutase (pgm), which interconverts 2- and 3-phosphoglyceric acid (pga), does not require 2,3-diphosphoglyceric acid for activity. however, this enzyme does have an absolute and specific requirement for mn(2+) ions for catalysis. here we report the crystal structure of this enzyme complexed with 3pga and manganese ions to 1.9 a resolution; this is the first crystal structure of a diphosphoglycerate-independent pgm to be determined. this information, plu ... | 2000 | 10747010 |
| reevaluation of the accepted allosteric mechanism of phosphofructokinase from bacillus stearothermophilus. | the binding of phosphoenolpyruvate (pep) to the single allosteric site on phosphofructokinase (ec ) from bacillus stearothermophilus (bspfk) diminishes the ability of the enzyme to bind the substrate fructose 6-phosphate (fru-6-p). comparisons of crystal structures with either fru-6-p or phosphoglycolate, an analog of pep, bound have shown that arg-162 interacts with the negatively charged fru-6-p. upon the binding of phosphoglycolate, arg-162 is virtually replaced by glu-161, which introduces a ... | 2000 | 10759544 |
| mechanism of catalysis of the cofactor-independent phosphoglycerate mutase from bacillus stearothermophilus. crystal structure of the complex with 2-phosphoglycerate. | the structure of the complex between the 2, 3-diphosphoglycerate-independent phosphoglycerate mutase (ipgm) from bacillus stearothermophilus and its 3-phosphoglycerate substrate has recently been solved, and analysis of this structure allowed formulation of a mechanism for ipgm catalysis. in order to obtain further evidence for this mechanism, we have solved the structure of this ipgm complexed with 2-phosphoglycerate and two mn(2+) ions at 1. 7-a resolution. the structure consists of two differ ... | 2000 | 10764795 |
| interaction of fmet-trna(fmet) with the c-terminal domain of translational initiation factor if2 from bacillus stearothermophilus. | analytical ultracentrifugation studies indicated that the c-terminal domains of if2 comprising amino acid residues 520-741 (if2 c) and 632-741 (if2 c-2) bind fmet-trna with similar affinities (k(d) at 25 degrees c equal to 0.27 and 0.23 microm, respectively). complex formation between fmet-trna(fmet) and if2 c or if2 c-2 is accompanied by barely detectable spectral changes as demonstrated by a comparison of the raman spectra of the complexes with the calculated sum of the spectra of the individu ... | 2000 | 10767407 |
| structure of the fmet-trna(fmet)-binding domain of b. stearothermophilus initiation factor if2. | the three-dimensional structure of the fmet-trna(fmet) -binding domain of translation initiation factor if2 from bacillus stearothermophilus has been determined by heteronuclear nmr spectroscopy. its structure consists of six antiparallel beta-strands, connected via loops, and forms a closed beta-barrel similar to domain ii of elongation factors ef-tu and ef-g, despite low sequence homology. two structures of the ternary complexes of the ef-tu small middle dotaminoacyl-trna small middle dot gdp ... | 2000 | 10775275 |
| construction and evaluation of a novel bifunctional n-carbamylase-d-hydantoinase fusion enzyme. | a fully enzymatic process employing two sequential enzymes, d-hydantoinase and n-carbamylase, is a typical case requiring combined enzyme activity for the production of d-amino acids. to test the possibility of generating a bifunctional fusion enzyme, we constructed a fusion protein via end-to-end fusion of a whole gene that encodes an intact protein at the n terminus of the d-hydantoinase. firstly, maltose-binding protein (mbp) gene of e. coli was fused with d-hydantoinase gene from bacillus st ... | 2000 | 10788392 |
| immobilization of functionally unstable catechol-2,3-dioxygenase greatly improves operational stability. | thermophilic catechol 2,3-dioxygenase (ec 1.13.11.2) from bacillus stearothermophilus has been immobilized on highly activated glyoxyl agarose beads. the enzyme could be fully immobilized at 4 degrees c and ph 10.05 with a high retention of activity (around 80%). enzyme immobilized under these conditions showed little increase in thermostability compared with the soluble enzyme, but further incubation of immobilized enzyme at 25 degrees c and ph 10.05 for 3 h before borohydride reduction resulte ... | 2000 | 10793203 |
| release of bacteria during the purge cycles of steam-jacketed sterilizers. | the design of the steam-jacketed sterilizer includes an exterior air-gap fixture through which purged chamber aerosols potentially could escape into the ambient environment. studies of the purge cycle in two sterilizer models tested the potential release of a genetically marked enterococcus faecalis, together with bacillus stearothermophilus spores introduced as exposed cultures. direct plate counts, broth enrichment and polymerase chain reaction analysis were used to confirm any released organi ... | 1999 | 10795367 |
| molecular analysis of maleate cis-trans isomerase from thermophilic bacteria. | several strains of thermophilic bacteria containing maleate cis-trans isomerase were isolated from soil samples and identified as bacillus stearothermophilus, bacillus circulans, bacillus brevis, and deleya halophila. the maleate cis-trans isomerase was purified and characterized from one of the isolated strains, b. stearothermophilus mi-102. the purified enzyme of strain mi-102 showed higher thermal stability than the enzyme of a mesophile, alcaligenes faecalis ifo13111. the seven maleate cis-t ... | 2000 | 10803955 |
| structure of apo-glyceraldehyde-3-phosphate dehydrogenase from palinurus versicolor. | d-glyceraldehyde-3-phosphate dehydrogenase (gapdh) shows cooperative properties for binding coenzymes. the structure of apo-gapdh from palinurus versicolor has been solved at 2.0 a resolution by x-ray crystallography. the final model gives a crystallographic r factor of 0.178 in the resolution range 8 to 2 a. the structural comparison with holo-gapdh from the same species reveals a conformational change induced by coenzyme binding similar to that observed in bacillus stearothermophilus gapdh but ... | 2000 | 10806086 |
| affinity purification of fusion chaperonin cpn60-(his)(6) from thermophilic bacterium bacillus strain ms and its use in facilitating protein refolding and preventing heat denaturation. | the cpn60 gene from bacillus strain ms, which is highly homologous to bacillus stearothermophilus, was cloned. cpn60 with a hexahistidine affinity tag (his)(6) fused to its c-terminus (cpn60-(his)(6)) was overproduced in escherichia coli. cpn60-(his)(6) was expressed in a soluble form in e. coli. and purified to homogeneity in a single step by nickel chelate affinity chromatography. cpn60-(his)(6) formed a tetradecamer and had atpase activity. cpn60-(his)(6) mediated refolding of guanidine hydro ... | 2000 | 10835247 |
| bacillus thermodenitrificans sp. nov., nom. rev. | a polyphasic study was performed on 10 soil isolates of thermophilic denitrifying bacillus strains from different geographical areas. the presence of two main characteristic bands following amplification of the internal transcribed spacer (its) region of rrn operons suggests a close relatedness to 'bacillus thermodenitrificans'. the isolates cluster around two strains of 'b. thermodenitrificans' in riboprint and fatty acid analyses, though differences occur at the strain level. subsequent dna-dn ... | 2000 | 10843079 |
| cloning and expression of the limonene hydroxylase of bacillus stearothermophilus br388 and utilization in two-phase limonene conversions. | a 3.6-kb fragment of bacillus stearothermophilus br388 chromosomal dna that confers growth on limonene to escherichia coli has been sequenced, revealing a single open reading frame encoding a single subunit limonene hydroxylase containing 444 amino acid residues. this enzyme proved capable of limonene hydroxylation to a mixture of carveol and perillyl alcohol as well as dehydrogenation of these products to carvone and perillyl aldehyde. oxygen, fad, and nadh were found to stimulate the hydroxyla ... | 2000 | 10849845 |
| the anti-sigma factor spoiiab forms a 2:1 complex with sigma(f), contacting multiple conserved regions of the sigma factor. | the developmental regulatory protein sigma(f) of bacillus subtilis, a member of the sigma(70)-family of bacterial rna polymerase sigma factors, is negatively regulated by the anti-sigma factor spoiiab, which binds to sigma(f), sequestering it in an inactive complex. spoiiab binding to sigma(f) is strongly stimulated by atp. here, we use a combination of gel filtration chromatography, dynamic light-scattering, analytical ultracentrifugation, limited proteolysis with n-terminal sequencing and elec ... | 2000 | 10864495 |
| [multiplicity of site-specific dna-methyltransferases of the bstf5i restriction modification system from bacillus stearothermophilus f5]. | 2000 | 10867922 | |
| substrate specificity in the highly heterogeneous m4 peptidase family is determined by a small subset of amino acids. | the members of the m4 peptidase family are involved in processes as diverse as pathogenicity and industrial applications. for the first time a number of m4 family members, also known as thermolysin-like proteases, has been characterized with an identical substrate set and a uniform set of assay conditions. characterization with peptide substrates as well as high performance liquid chromatography analysis of beta-casein digests shows that the m4 family is a homogeneous family in terms of catalysi ... | 2000 | 10869357 |
| btri, a novel restriction endonuclease, recognises the non-palindromic sequence 5'-cacgtc(-3/-3)-3'. | the recognition sequence and cleavage positions of a new restriction endonuclease btr:i isolated from bacillus stearothermophilus se-u62 have been determined. btr:i belongs to a rare type iiq of restriction endonucleases, which recognise non-palindromic nucleotide sequences and cleave dna symmetrically within them. | 2000 | 10871355 |
| membrane lipid composition of bacillus stearothermophilus as affected by lipophilic environmental pollutants: an approach to membrane toxicity assessment. | the thermophilic eubacterium bacillus stearothermophilus is used as a model to identify membrane perturbing effects of lipophilic compounds. a parallelism has been established between the toxicity of the organochlorine insecticide ddt and its metabolite, dde, in bacterial growth and the effects on cell functions and physical perturbations induced at the membrane (donato et al. 1997a, arch environ contam toxicol 33:109-116; donato et al. 1997b, appl environ microbiol 63:4948-495). in the present ... | 2000 | 10871416 |
| serine and alanine racemase activities of vant: a protein necessary for vancomycin resistance in enterococcus gallinarum bm4174. | vancomycin resistance in enterococcus gallinarum results from the production of udp-murnac-pentapeptide[d-ser]. vant, a membrane-bound serine racemase, is one of three proteins essential for this resistance. to investigate the selectivity of racemization of l-ser or l-ala by vant, a strain of escherichia coli tkl-10 that requires d-ala for growth at 42 degrees c was used as host for transformation experiments using plasmids containing the full-length vant from ent. gallinarum or the alanine race ... | 2000 | 10878136 |
| mechanism of product chain length determination for heptaprenyl diphosphate synthase from bacillus stearothermophilus. | a member of the medium-chain prenyl diphosphate synthases, bacillus stearothermophilus heptaprenyl diphosphate synthase, catalyzes the consecutive condensation of isopentenyl diphosphate with allylic diphosphate to produce (all-e)-c35 prenyl diphosphate as the ultimate product. we previously showed that the product specificity of short-chain prenyl diphosphate synthases is regulated by the structure around the first aspartate-rich motif (farm). the farm is also conserved in a subunit of heptapre ... | 2000 | 10880976 |
| menaquinol oxidase activity and primary structure of cytochrome bd from the amino-acid fermenting bacterium corynebacterium glutamicum. | cytochrome d was spectroscopically detected in membrane fractions of the amino-acid-fermenting, high-g+c gram-positive bacterium corynebacterium glutamicum. inhibition of nadh oxidase activity in the membranes by cyanide suggested that the main terminal respiratory oxidase during the stationary phase was a type of cytochrome bd. cytochrome bd-type quinol oxidase, purified from the membranes, was composed of two subunits. its reduced form showed absorption peaks at 627, 595, and 560 nm, which wer ... | 2000 | 10896219 |
| characterization and kinetic mechanism of mono- and bifunctional ornithine acetyltransferases from thermophilic microorganisms. | the argj gene coding for n2-acetyl-l-ornithine: l-glutamate n-acetyltransferase, the key enzyme involved in the acetyl cycle of l-arginine biosynthesis, has been cloned from thermophilic procaryotes: the archaeon methanoccocus jannaschii, and the bacteria thermotoga neapolitana and bacillus stearothermophilus. archaeal argj only complements an escherichia coli arge mutant (deficient in acetylornithinase, which catalyzes the fifth step in the linear biosynthetic pathway), whereas bacterial genes ... | 2000 | 10931207 |
| production of d-amino acid using whole cells of recombinant escherichia coli with separately and coexpressed d-hydantoinase and n-carbamoylase. | we developed a fully enzymatic process employing d-hydantoinase and n-carbamoylase for the production of d-amino acid from 5'-monosubstituted hydantoin. for the comparison of the reaction systems using two sequential enzymes, d-hydantoinase of bacillus stearothermophilus sd1 and n-carbamoyl-d-amino acid amidohydrolase (n-carbamoylase) of agrobacterium tumefaciens nrrl b11291 were separately expressed in each host cell and coexpressed in the same host cell. a high level and constitutive expressio ... | 2000 | 10933829 |
| glucose catabolism of escherichia coli strains with increased activity and altered regulation of key glycolytic enzymes. | this study investigates the effect of overexpression of key glycolytic enzymes exhibiting either native or alternative allosteric regulation on glucose bioconversion by resting escherichia coli cells previously engineered for ethanol production. homologous and heterologous pyruvate kinases (pyk) and phosphofructokinases (pfk) were individually and simultaneously overexpressed. overexpression of the e. coli pfk led to a shift from ethanol to lactate formation (three-fold above the control level) ... | 1999 | 10935925 |
| engineering direct fructose production in processed potato tubers by expressing a bifunctional alpha-amylase/glucose isomerase gene complex. | manipulation of starch biosynthesis/degradation and formation of novel molecules in storage organs of plants through genetic engineering is an attractive but technically challenging goal. we report here, for the first time, that starch was degraded and glucose and fructose were produced directly when crushed potato tubers expressing a starch degrading bifunctional gene were heated for 45 minutes at 65 degrees c. to achieve this, we have constructed a fusion gene encoding the thermostable enzymes ... | 2000 | 10940858 |
| analysis of oxidation sensitivity of maleate cis-trans isomerase from serratia marcescens. | the maleate cis-trans isomerase gene (maia) from serratia marcescens ifo3736 was cloned and sequenced. serratia maia has 62.4% amino acid identity with alcaligenes faecalis ifo13111 maia and 64.9% with bacillus stearothermophilus mi-102 maia. all known ten amino acid sequences of maia had significant conserved regions containing cysteine residues, which were previously suggested to be involved in an active site of the enzyme. the maia gene was expressed in escherichia coli, and expressed product ... | 2000 | 10945267 |
| identification of a potential metal cation-pi binding site in the structure of a thermophilic bacillus stearothermophilus triosephosphate isomerase mutant. | a potential metal cation-pi interaction between a sodium cation (na(+)) and the indole ring of a tryptophan residue was detected in the crystallographic structure (2 a) of the thermophilic bacillus stearothermophilus triosephosphate isomerase h12n/k13g mutant (btimmut). the cation-pi binding site is located near the surface of the protein, the alkali metal ion facing the benzo ring of trp9. the presence of phe21 and glu17 close to trp9 could indicate an additional role for those residues in the ... | 2000 | 10957646 |
| surface-accessible residues in the monomeric and assembled forms of a bacterial surface layer protein. | the s-layer protein sbsb of the thermophilic, gram-positive organism bacillus stearothermophilus pv72/p2 forms a crystalline, porous array constituting the outermost component of the cell envelope. sbsb has a molecular mass of 98 kda, and the corresponding s-layer exhibits an oblique lattice symmetry. to investigate the molecular structure and assembly of sbsb, we replaced 75 residues (mainly serine, threonine, and alanine), located throughout the primary sequence, with cysteine, which is not fo ... | 2000 | 10969072 |
| isbst12, a novel type of insertion-sequence element causing loss of s-layer-gene expression in bacillus stearothermophilus atcc 12980. | the cell surface of the surface layer (s-layer)-carrying strain of bacillus stearothermophilus atcc 12980 is completely covered with an oblique lattice composed of the s-layer protein sbsc. in the s-layer-deficient strain, thes-layer gene sbsc was still present but was interrupted by a novel type of insertion sequence (is) element designated isbst12. the insertion site was found to be located within the coding region of the sbsc gene, 199 bp downstream from the translation start of sbsc. isbst12 ... | 2000 | 10974105 |
| molecular characterization of the transition state regulator abrb from bacillus stearothermophilus. | the bacillus subtilis transition state regulator abrb(su) is a dna-binding protein that acts on several genes either as activator, repressor, or preventer. however, among genes under its control, neither common binding sites could be identified nor could the structural features of this broad and specific interaction be elucidated. attempts to elucidate these interesting features by crystallizing abrb(su) have failed so far. therefore, to solve this problem, we focused in this work on identifying ... | 2000 | 10978510 |
| amiodarone interactions with membrane lipids and with growth of bacillus stearothermophilus used as a model. | the thermophilic eubacterium bacillus stearothermophilus was used as a model to study the effects of amiodarone (2-butyl-3-[3',5'diido-4'alpha-diethylaminoethoxybenzoyl]-be nzofuran) in lipid organization and in bacterial growth. effects on the structural order of lipids were assessed by fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (dph), probing the bilayer core, and of the propionic acid derivative 3-[p-(6-phenyl)-1,3,5-hexatrienyl] phenylpropionic acid (dph-pa), probing the oute ... | 2000 | 10982227 |
| toxicity assessment of tamoxifen by means of a bacterial model. | a strain of bacillus stearothermophilus was used as a model to study physical perturbations induced in the membrane by the cytostatic tamoxifen (tam). this study was carried out using two lines of criteria: (1) bacterial growth, and temperature growth range, with determination of growth parameters as a function of tam concentration; and (2) biophysical studies by differential scanning calorimetry (dsc) and by means of two fluorescent probes to evaluate perturbations promoted by the drug on the s ... | 2000 | 10982231 |
| the transposable element is4712 prevents s-layer gene (sbsa) expression in bacillus stearothermophilus and also affects the synthesis of altered surface layer proteins. | cell surface (s)-layer protein synthesis in bacillus stearothermophilus pv72/p6 is blocked when cells are grown at elevated temperature. from a culture exhibiting the s-layer-negative phenotype, the s-layer deficient mutant t5 (sbsa-) was isolated. genetic analysis of the s-layer-encoding gene (sbsa) of mutant t5 revealed an insertion element (is4712) integrated into the upstream regulatory region of the s-layer gene, thereby blocking sbsa transcription. the insertion element consists of 1371 ba ... | 2000 | 10985748 |
| mapping the fmet-trna(f)(met) binding site of initiation factor if2. | the interaction between fmet-trna(f)(met) and bacillus stearothermophilus translation initiation factor if2 has been characterized. we demonstrate that essentially all thermodynamic determinants governing the stability and the specificity of this interaction are localized within the acceptor hexanucleotide fmet-3'accaac of the initiator trna and a fairly small area at the surface of the beta-barrel structure of the 90-amino acid c-terminal domain of if2 (if2 c-2). a weak but specific interaction ... | 2000 | 11013225 |
| lipid composition and dynamics of cell membranes of bacillus stearothermophilus adapted to amiodarone. | bacillus stearothermophilus, a useful model to evaluate membrane interactions of lipophilic drugs, adapts to the presence of amiodarone in the growth medium. drug concentrations in the range of 1-2 microm depress growth and 3 microm completely suppresses growth. adaptation to the presence of amiodarone is reflected in lipid composition changes either in the phospholipid classes or in the acyl chain moieties. significant changes are observed at 2 microm and expressed by a decrease of phosphatidyl ... | 2000 | 11018480 |
| correlating amino acid conservation with function in tyrosyl-trna synthetase. | sequence comparisons have been combined with mutational and kinetic analyses to elucidate how the catalytic mechanism of bacillus stearothermophilus tyrosyl-trna synthetase evolved. catalysis of trna(tyr) aminoacylation by tyrosyl-trna synthetase involves two steps: activation of the tyrosine substrate by atp to form an enzyme-bound tyrosyl-adenylate intermediate, and transfer of tyrosine from the tyrosyl-adenylate intermediate to trna(tyr). previous investigations indicate that the class i cons ... | 2000 | 11023793 |
| stabilization of the transition state for the transfer of tyrosine to trna(tyr) by tyrosyl-trna synthetase. | aminoacylation of trna(tyr) involves two steps: (1) tyrosine activation to form the tyrosyl-adenylate intermediate; and (2) transfer of tyrosine from the tyrosyl-adenylate intermediate to trna(tyr). in bacillus stearothermophilus tyrosyl-trna synthetase, asp78, tyr169, and gln173 have been shown to form hydrogen bonds with the alpha-ammonium group of the tyrosine substrate during the first step of the aminoacylation reaction. asp194 and gln195 stabilize the transition state complex for the first ... | 2000 | 11023794 |
| cloning and characterization of the str operon and elongation factor tu expression in bacillus stearothermophilus. | the complete primary structure of the str operon of bacillus stearothermophilus was determined. it was established that the operon is a five-gene transcriptional unit: 5'-ybxf (unknown function; homology to eukaryotic ribosomal protein l30)-rpsl (s12)-rpsg (s7)-fus (elongation factor g [ef-g])-tuf (elongation factor tu [ef-tu])-3'. the main operon promoter (strp) was mapped upstream of ybxf, and its strength was compared with the strength of the tuf-specific promoter (tufp) located in the fus-tu ... | 2000 | 11029432 |
| characterization of the rela/spot gene from bacillus stearothermophilus. | by use of degenerate primers, we amplified a fragment of a rela/spot homologous gene from bacillus stearothermophilus. chromosomal walking enabled us to sequence the entire gene and its flanking regions. the primary sequence of the gene product is 78% identical to the rela/spot homologue of bacillus subtilis and both gene loci share a similar genetic organization. the b. stearothermophilus rel gene was analyzed in vivo by heterologous expression in the b. subtilis rela deletion strain tw30, and ... | 2000 | 11034279 |
| structural characterization of penicillin-binding protein-related factor a (prfa) from bacillus species. | the prfa genes of bacillus stearothermophilus and bacillus subtilis are in an operon downstream of the pona gene encoding penicillin-binding protein 1 (pbp1), a major enzyme involved in peptidoglycan synthesis. the specific function of the 23- to 24-kda prfa protein is unknown but this protein plays some role in nucleoid segregation and the functions of prfa and pbp1 are interrelated. we overexpressed b. stearothermophilus and b. subtilis prfa in escherichia coli and purified the proteins to hom ... | 2000 | 11042079 |
| purification and characterization of the highly thermostable proteases from bacillus stearothermophilus tls33. | three thermostable proteases, designated s, n, and b, are extracellular enzymes produced by bacillus stearothermophilus strain tls33. they were purified by lysine affinity chromatography, strong anion exchange q hyperd chromatography, and ultrogel aca44 gel filtration. the molecular masses of the enzymes determined by sds-page and zymography were approximately 36, 53, and 71 kda, respectively. thermostable protease s bound strongly to the lysine affinity column and could be purified by this sing ... | 2000 | 11049738 |
| ancient adaptation of the active site of tryptophanyl-trna synthetase for tryptophan binding. | the amino acid binding domains of the tryptophanyl (trprs)- and tyrosyl-trna synthetases (tyrrs) of bacillus stearothermophilus are highly homologous. these similarities suggest that conserved residues in trprs may be responsible for both determining tryptophan recognition and discrimination against tyrosine. this was investigated by the systematic mutation of trprs residues based upon the identity of homologous positions in tyrrs. of the four residues which interact directly with the aromatic s ... | 2000 | 11052665 |
| thermally induced disintegration of the bacillus stearothermophilus dihydrolipoamide dehydrogenase. | upon heat treatment of the pyruvate dehydrogenase complex from bacillus stearothermophilus, the most thermostable component is a dihydrolipoamide dehydrogenase (e3c). to understand this stability, the thermal disintegration of e3 dissociated from the complex (e3d) was examined, comparing with that of e3c. judging from residual activity and inactivation rate, e3d was less thermostable than e3c; e3d and e3c lost half of their original activities upon incubations for 30 min at 79 degrees c and 90 d ... | 2000 | 11055397 |
| the effect of media composition on the thermal resistance of bacillus stearothermophilus. | spores of bacillus stearothermophilus atcc 7953 were developed at 62 degrees c on 32 media composed of various amounts of 11 components: d-glucose, l-glutamic acid, yeast extract, peptone, sodium chloride, magnesium sulfate, ammonium phosphate, potassium phosphate, calcium chloride, ferrous sulfate and manganese sulfate. statistical models were used and demonstrated a strong interaction of yeast/peptone/ammonium phosphate, contributing positively to the best sporulation yield (6-7 log10 spores). ... | 2000 | 11057096 |
| [study on continuous synthesis of galacto-oligosaccharide by immobilized bacillus stearothermophilus]. | the galacto-oligosaccharide was synthesized continuously by immobilized bacillus stearothermophilu producing beta-galactosidase in fibrous bed reactor. the effect of substrate concentration, ph, reaction temperature and retention time on production of gos was investigated. the optimal reaction conditions were determined. substrate concentration were 450 g/l; reaction temperature was 55 degrees c; ph was 7.0; residence time was 100 min. the product yield reached up to 50.7%. gos synthesis was pro ... | 2000 | 11059288 |
| structural preordering in the n-terminal region of ribosomal protein s4 revealed by heteronuclear nmr spectroscopy. | protein s4, a component of the 30s subunit of the prokaryotic ribosome, is one of the first proteins to interact with rrna in the process of ribosome assembly and is known to be involved in the regulation of this process. while the structure of the c-terminal 158 residues of bacillus stearothermophilus s4 has been solved by both x-ray crystallography and nmr, that of the n-terminal 41 residues is unknown. evidence suggests that the n-terminus is necessary both for the assembly of functional ribo ... | 2000 | 11063598 |
| high catalytic activity of alanine racemase from psychrophilic bacillus psychrosaccharolyticus at high temperatures in the presence of pyridoxal 5'-phosphate. | we examined the effect of the pyridoxal 5'-phosphate (plp) cofactor on the activity and stability of the psychrophilic alanine racemase, having a high catalytic activity at low temperature, from bacillus psychrosaccharolyticus at high temperatures. the decrease in the enzyme activity at incubation temperatures over 40 degrees c was consistent with the decrease in the amount of bound plp. unfolding of the enzyme at temperatures above 40 degrees c was suppressed in the presence of plp. in the pres ... | 2000 | 11064190 |
| the trans-activation domain of the sporulation response regulator spo0a revealed by x-ray crystallography. | sporulation in bacillus involves the induction of scores of genes in a temporally and spatially co-ordinated programme of cell development. its initiation is under the control of an expanded two-component signal transduction system termed a phosphorelay. the master control element in the decision to sporulate is the response regulator, spo0a, which comprises a receiver or phosphoacceptor domain and an effector or transcription activation domain. the receiver domain of spo0a shares sequence simil ... | 2000 | 11069648 |
| genomic analysis of the genes encoding ribosomal proteins in eight eubacterial species and saccharomyces cerevisiae. | the complete genomic nucleotide sequence data of more than 10 unicellular organisms have become available. during the past years, we have been focusing our attention to the analysis of the structure and function of the ribosome and its protein components. by making use of the genomic sequence data, our work can now be extended to comparative analysis of the ribosomal components at the genomic level. such analysis will contribute to our understanding of the structure-function relationship of the ... | 1998 | 11072316 |
| comparative study of new alpha-galactosidases in transglycosylation reactions. | we have studied the potential of several newly cloned alpha-galactosidases to catalyze the regioselective synthesis of disaccharides using 4-nitrophenylgalactoside as a donor. the kinetics of the reactions were followed by in situ nmr spectroscopy. the following thermophilic enzymes have been tested: aga a and an isoenzyme aga b obtained from the strain kve39 and aga 285 from the strain it285 of bacillus stearothermophilus; aga t is an alpha-galactosidase from thermus brockianus (strain it360). ... | 2000 | 11086687 |
| effect of calcium in assay medium on d value of bacillus stearothermophilus atcc 7953 spores. | the d value of commercial biological indicator spore strips using bacillus stearothermophilus atcc 7953 was increased by higher calcium concentrations in assay media. the calcium concentration in assay media varied among the manufacturers. the calcium concentration in assay media is an important factor to consider to minimize the variation of d value. | 2000 | 11097939 |
| sites of limited proteolysis in the pyruvate decarboxylase component of the pyruvate dehydrogenase multienzyme complex of bacillus stearothermophilus and their role in catalysis. | the e1 component (pyruvate decarboxylase) of the pyruvate dehydrogenase complex of bacillus stearothermophilus is a heterotetramer (alpha2beta2) of e1alpha and e1beta polypeptide chains. the domain structure of the e1alpha and e1beta chains, and the protein-protein interactions involved in assembly, have been studied by means of limited proteolysis. it appears that there may be two conformers of e1alpha in the e1 heterotetramer, one being more susceptible to proteolysis than the other. a highly ... | 2000 | 11106427 |
| site-specific and random immobilization of thermolysin-like proteases reflected in the thermal inactivation kinetics. | immobilization of proteins usually leads to random orientation of the molecules on the surface of the carrier material, whereby mechanistic interpretations of changes in properties, such as thermal stability, become very difficult. recently, we have prepared several mutant enzymes of the thermolysin-like neutral protease from bacillus stearothermophilus, containing cysteine residues in different positions on the surface of the protein molecule. these enzymes allowed site-specific immobilization ... | 2000 | 11115391 |
| new syntheses of 1d- and 1l-1,2-anhydro-myo-inositol and assessment of their glycosidase inhibitory activities. | the 1d and 1l enantiomers of 1,2-anhydro-myo-inositol (conduritol b epoxide) were synthesised from 1d-pinitol and 1l-quebrachitol, respectively, and their activities were compared in selected glycosidase inhibition assays. the 1d enantiomer was found to be the active isomer, functioning as an irreversible inhibitor of sweet almond beta-d-glucosidase. neither isomer was active against the alpha-d-glucosidase from bacillus stearothermophilus or the beta-d-galactosidase from aspergillus oryzae. | 2000 | 11117313 |
| superoxide dismutase biosynthesis by two thermophilic bacteria. | some high-molecular weight antioxidant defense system components of two thermophilic bacteria isolated from spa waters of serbia (yugoslavia) and identified as bacillus stearothermophilus and thermothrix sp. were studied. in addition to superoxide dismutase (sod; ec 1.15.1.1), qualitative analyses demonstrated the presence of catalase (ec 1.11.1.6), peroxidases and oxidases in both bacterial strains. cell-free extracts were subjected to nondenaturing polyacrylamide gel electrophoresis (page) and ... | 2000 | 11118588 |
| multiple display of peptides and proteins on a macromolecular scaffold derived from a multienzyme complex. | the acyltransferase components (e2) from the family of 2-oxo acid dehydrogenase multienzyme complexes form large protein scaffolds, to which multiple copies of peripheral enzymes bind tightly but non-covalently. sixty copies of the e2 polypeptide from the pyruvate dehydrogenase multienzyme complex of bacillus stearothermophilus assemble to form a pentagonal dodecahedral scaffold with icosahedral symmetry. this protein scaffold can be modified to present foreign peptides and proteins on its surfa ... | 2001 | 11124904 |
| active site structure of soxb-type cytochrome bo3 oxidase from thermophilic bacillus. | two-subunit soxb-type cytochrome c oxidase in bacillus stearothermophilus was over-produced, purified, and examined for its active site structures by electron paramagnetic resonance (epr) and resonance raman (rr) spectroscopies. this is cytochrome bo3 oxidase containing heme b at the low-spin heme site and heme o at the high-spin heme site of the binuclear center. epr spectra of the enzyme in the oxidized form indicated that structures of the high-spin heme o and the low-spin heme b were similar ... | 2000 | 11132640 |
| purification, crystallization and quaternary structure analysis of a glycerol dehydrogenase s305c mutant from bacillus stearothermophilus. | bacillus stearothermophilus glycerol dehydrogenase (glydh) is a 39.5 kda molecular weight metalloenzyme which catalyzes the oxidation of glycerol to dihydroxyacetone with the concomitant reduction of nad(+) to nadh. despite its classification as a member of the 'iron-containing' polyol dehydrogenase family, studies on recombinant b. stearothermophilus glydh have shown this enzyme to be zn(2+)-dependent. crystals of a s305c glydh mutant were obtained by the hanging-drop vapour-diffusion method, u ... | 2001 | 11134946 |
| cysteine-scanning mutagenesis reveals a highly amphipathic, pore-lining membrane-spanning helix in the glutamate transporter gltt. | the carboxyl-terminal membrane-spanning segment 8 of the glutamate transporter gltt of bacillus stearothermophilus was studied by cysteine-scanning mutagenesis. 21 single cysteine mutants were constructed in a stretch ranging from gly-374 to gln-404. two mutants were not expressed, four were inactive, and two showed severely reduced glutamate transport activity. cysteine mutations at the other positions were well tolerated. only the two most amino- and carboxyl-terminal mutants (g374c, i375c, s3 ... | 2001 | 11148213 |
| effects of steam sterilization on thermogelling chitosan-based gels. | a new thermogelling chitosan-glycerophosphate system has been recently proposed for biomedical applications such as drug and cell delivery. the objectives of this work were to characterize the effect of steam sterilization on the in vitro and in vivo end performances of the gel and to develop a filtration-based method to assess its sterility. autoclaving 2% (w/v) chitosan solutions for as short as 10 min resulted in a 30% decrease in molecular weight, 3-5-fold decrease in dynamic viscosity, and ... | 2001 | 11153009 |
| characterization of the specific dna nicking activity of restriction endonuclease n.bstnbi. | n.bstnbi is a unique restriction endonuclease isolated from bacillus stearothermophilus. we have characterized the recognition sequence and the cleavage site of n.bstnbi. mapping of cleavage sites of n.bstnbi showed that it recognizes an asymmetric sequence, 5' gagtc 3', and cleaves only on the top strand 4 base pairs away from its recognition sequence. to verify the nicking activity of n. bstnbi, we have constructed two plasmids containing a single recognition sequence (pnb1) or no recognition ... | 2000 | 11154070 |