| [possibility of dna-ligase participation in regulating the synthesis and degradation of heat-damaged dna in permeable bacillus stearothermophilus cells]. | the chromosome of bacillus stearothermophilus was found to contain apurine regions which were repaired mainly by excisions. in the permeable cells of the thermophilic bacterium, the observed intensive degradation and resynthesis of dna were regulated by active dna ligase. in this case, nad (the cofactor of ligase) sharply inhibited the atp-dependent and independent synthesis of dna. apparently, dna ligase may be involved in the regulation of degradation and resynthesis of dna with thermal lesion ... | 1980 | 7442567 |
| [functional model of mn-superoxide dismutase from bacillus stearothermophilus]. | | 1980 | 7448234 |
| purificaton of the pyruvate dehydrogenase multienzyme complex of bacillus stearothermophilus and resolution of its four component polypeptides. | 1. the pyruvate dehydrogenase complex was purified from bacillus stearothermophilus in high yield. the specific activity (about 40nkat/mg of protein) was substantially lower than that of the pyruvate dehydrogenase complex from escherchia coli (about 570nkat/mg of protein) measured at 30 degrees c under the same conditions. 2. the relative molecular masses of the four types of polypeptide chain i the complex were estimated by means of sodium dodecyl sulphate/polyacrylamide-gel electrophoresis to ... | 1980 | 7458900 |
| purification and properties of deoxyribonucleic acid polymerase from bacillus stearothermophilus. | deoxyribonucleic acid polymerase i was purified from bacillus stearothermophilus to 50 to 70% homogeneity. its molecular weight was 76,000. the enzyme was insensitive to sulfhydryl blocking agents and showed maximal activity at 60 degrees c, ph 8 to 9, 0.25 m kcl, and 0.02 m mgso4. the rate of heat inactivation of the deoxyribonucleic acid polymerase followed first-order kinetics with a half-life of 90 min at 60 degrees c; the addition of 0.05% bovine serum albumin protected the enzyme, which co ... | 1981 | 7462144 |
| sequence homology in the amino-terminal and active-site regions of thermolabile glyceraldehyde-3-phosphate dehydrogenase from a thermophile. | the unusual thermolability of glyceraldehyde-3-phosphate dehydrogenase from the facultative thermophile bacillus coagulans ku (crabb et al., biochemistry 16:4840-4847, 1977) has provided the first opportunity to study a homologous enzyme from the same genus that exhibits a marked difference in thermostability. in pursuit of the structural bases for the thermostability of proteins, the sequences of the amino terminus (residues 1 through 27) and the active-site cysteine cyanogen bromide peptide (r ... | 1981 | 7462149 |
| the use of various immobilized-triazine affinity dyes for the purification of 6-phosphogluconate dehydrogenase from bacillus stearothermophilus. | 1. 6-phosphogluconate dehydrogenase from bacillus stearothermophilus was purified approximately 260-fold on triazine-immobilized dye columns to a final specific activity of 54 mumol of nadp+ reduced/min per mg of protein and an overall yield of 62%. 2. an investigation of the capacities of different triazine dyes that inhibit 6-phosphogluconate dehydrogenase was carried out. cibacron blue f3g-a and procion red he-3b strongly inhibited the enzyme in free solution and were therefore chosen as the ... | 1980 | 7470099 |
| an integrated kinetic analysis of intermediates and transition states in protein folding reactions. | relaxation rates for folding and unfolding of two proteins have been measured over a range of denaturant concentrations to examine the reaction pathways leading to the late transition state. the proteins were chosen for their marked differences in both kinetic and structural properties. results for the n-terminal domain of phosophoglycerate kinase (n-pgk), from bacillus stearothermophilus, reveal the existence of a single intermediate (pathway = u-i-f), and obey the general relationship: kobs = ... | 1995 | 7473751 |
| effectiveness of steam sterilization in killing spores of bacillus stearothermophilus in prophylaxis angles. | | 1994 | 7489880 |
| solution structure of the hu protein from bacillus stearothermophilus. | the histone-like protein hu from bacillus stearothermophilus is a dimer with a molecular mass of 19.5 kda that is capable of bending dna. an x-ray structure has been determined, but no structure could be established for a large part of the supposed dna-binding beta-arms. using distance and dihedral constraints derived from triple-resonance nmr data of a 13c/15n doubly-labelled hu protein 49 distance geometry structures were calculated, which were refined by means of restrained molecular dynamics ... | 1995 | 7500343 |
| clustering and co-transcription of the bacillus subtilis genes encoding the aminoacyl-trna synthetases specific for glutamate and for cysteine and the first enzyme for cysteine biosynthesis. | the bacillus subtilis cyse and cyss genes encoding, respectively, the serine acetyltransferase and the cysteinyl-trna synthetase were found downstream from the gltx gene encoding the glutamyl-trna synthetase. this gene organization is also conserved in bacillus stearothermophilus where the cyse and cyss genes show high amino acid identity with those of b. subtilis. in both organisms the coding sequences of cyse and cyss overlap, suggesting a translational coupling. b. subtilis cyse and cyss were ... | 1994 | 7510287 |
| the s-layer from bacillus stearothermophilus dsm 2358 functions as an adhesion site for a high-molecular-weight amylase. | the s-layer lattice from bacillus stearothermophilus dsm 2358 completely covers the cell surface and exhibits oblique symmetry. during growth of b. stearothermophilus dsm 2358 on starch medium, three amylases with molecular weights of 58,000, 98,000, and 184,000 were secreted into the culture fluid, but only the high-molecular-weight enzyme was found to be cell associated. studies of interactions between cell wall components and amylases revealed no affinity of the high-molecular-weight amylase ... | 1995 | 7533757 |
| comparison of primary structures and substrate specificities of two pullulan-hydrolyzing alpha-amylases, tva i and tva ii, from thermoactinomyces vulgaris r-47. | thermoactinomyces vulgaris r-47 produces two alpha-amylases, tva i, an extracellular enzyme, and tva ii, an intracellular enzyme. both enzymes hydrolyze pullulan to produce panose, and also hydrolyze cyclodextrins. we cloned and sequenced the tva i gene. the tva i gene consisted of 1833 base pairs, and the deduced primary structure was composed of 611 amino-acid residues, including an n-terminal signal sequence consisting of 29 amino-acid residues. the similarity between the amino-acid sequence ... | 1995 | 7548164 |
| protein-rrna binding features and their structural and functional implications in ribosomes as determined by cross-linking studies. | we have investigated protein-rrna cross-links formed in 30s and 50s ribosomal subunits of escherichia coli and bacillus stearothermophilus at the molecular level using uv and 2-iminothiolane as cross-linking agents. we identified amino acids cross-linked to rrna for 13 ribosomal proteins from these organisms, namely derived from s3, s4, s7, s14, s17, l2, l4, l6, l14, l27, l28, l29 and l36. several other peptide stretches cross-linked to rrna have been sequenced in which no direct cross-linked am ... | 1995 | 7556101 |
| characterization of superoxide dismutase genes from gram-positive bacteria by polymerase chain reaction using degenerate primers. | an internal fragment representing approximately 85% of sod genes from seven gram-positive bacteria was amplified by using degenerate primers in a polymerase chain reaction assay. the dna sequences of sod polymerase chain reaction products from clostridium perfringens, enterococcus faecalis, enterococcus faecium, lactococcus lactis, staphylococcus aureus, streptococcus agalactiae, streptococcus pneumoniae, and streptococcus pyogenes were determined. comparisons of their deduced amino acid sequenc ... | 1995 | 7557308 |
| cloning and complete sequence of the dna polymerase-encoding gene (bstpoli) and characterisation of the klenow-like fragment from bacillus stearothermophilus. | a fragment of the dna polymerase i-encoding gene (poli) from bacillus stearothermophilus (bst) was obtained by pcr. this was used as a probe to obtain a full-length gene from a bst genomic dna (gdna) plasmid library. comparison of the sequence to b. caldotenax (bca) showed about 93% homology at the amino acid (aa) level. a klenow-like (bstpolik) clone was developed and the recombinant protein displayed dna polymerase activity similar to the wild-type bstpoli enzyme. | 1995 | 7557480 |
| novel insertion sequence-like element is982 in lactococci. | a novel insertion sequence-like (is) element, designated is982, was found on the lactose plasmid, psk11l, from lactococcus lactis subsp. cremoris sk11 and was located between the origin of replication and the oligopeptide transport gene cluster. the 1003-base pair (bp) is982 was flanked by 18-bp perfect inverted repeats. is982 contained an open reading frame encoding a putative transposase of 296 amino acids. an almost identical is-like element (99% dna sequence identity) was cloned and partiall ... | 1995 | 7568469 |
| stringency of substrate specificity of escherichia coli malate dehydrogenase. | malate dehydrogenase and lactate dehydrogenase are members of the structurally and functionally homologous family of 2-ketoacid dehydrogenases. both enzymes display high specificity for their respective keto substrates, oxaloacetate and pyruvate. closer analysis of their specificity, however, reveals that the specificity of malate dehydrogenase is much stricter and less malleable than that of lactate dehydrogenase. site-specific mutagenesis of the two enzymes in an attempt to reverse their speci ... | 1995 | 7574693 |
| purification and partial characterization of a novel thermophilic carboxylesterase with high mesophilic specific activity. | an esterase activity obtained from a strain of bacillus stearothermophilus was purified 5,133-fold to electrophoretic homogeneity with 26% recovery. the purified esterase had a specific activity of 2,032 mumol min-1 mg-1 based on the hydrolysis of p-nitrophenyl caproate at ph 7.0 and 30 degrees c. the apparent molecular mass was 50,000 +/- 2,000 daltons from sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 45,000 +/- 3,000 daltons from gel filtration. native polyacrylamide gels stai ... | 1995 | 7576531 |
| biological indicators for low temperature steam and formaldehyde sterilization: the effect of defined media on sporulation, growth index and formaldehyde resistance of spores of bacillus stearothermophilus strains. | preliminary screening was carried out on spores of 29 strains of bacillus stearothermophilus to determine their potential as biological indicator organisms for low temperature steam and formaldehyde sterilization. each strain was sporulated on four chemically defined media. fourteen strains produced satisfactory sporulation on one or more of the media but there was considerable variation in the extent of sporulation. the growth index of the spores, which was dependent on both the strain of organ ... | 1995 | 7592136 |
| comparative evaluation of the antibacterial effects of intracanal nd:yag laser irradiation: an in vitro study. | the purpose of this study was to determine if the nd:yag laser was capable of disinfecting contaminated root canals in vitro. eighty canals of extracted single-rooted teeth were prepared to size 35 k-file. the teeth were sterilized with ethylene oxide gas and then inoculated with bacillus stearothermophilus. eight groups were treated as follows: 1, sterility control; 2, positive control, no treatment; 3, hand instrumentation with sterile water filling chamber; 4, hand instrumentation with naocl ... | 1995 | 7595155 |
| thermostability of respiratory terminal oxidases in the lipid environment. | the effect of the lipid environment on the thermostability of three respiratory terminal oxidases was determined. cytochrome-c oxidase from beef heart and bacillus stearothermophilus were used as representative proteins from mesophilic and thermophilic origin, respectively. quinol oxidase from the archaeon sulfolobus acidocaldarius represented the model for a extreme thermoacidophilic enzyme. all three integral membrane proteins were tested for their thermal inactivation in detergent and after r ... | 1995 | 7612641 |
| [microbial resistance to formaldehyde. iii> dependence of the microbial effect on staphylococcus aureus, enterococcus faecium and spores of bacillus stearothermophilus on temperature]. | temperature dependence of microbicidal efficacy of formaldehyde was examined with suspension tests (ph 7.0). test germs were staphylococcus aureus, enterococcus faecium and spores of bacillus stearothermophilus. the methodology was nearly the same as in previous investigations (5, 7). at given exposure periods and temperatures formaldehyde concentrations necessary to produce a microbicidal effect of log (n/n0) = -4.0 (concentrations of equal efficacy) were determined. n and n0 represent the numb ... | 1995 | 7619203 |
| modified microbiological method for the screening of antibiotics in milk. | the bacillus stearothermophilus disc assay is routinely used by the dairy industry to screen milk for antibiotic residues. although the assay detects the presence of beta-lactam antibiotics, it does not distinguish cephalosporins from other beta-lactam antibiotics. in this study, the b. stearothermophilus disc assay was modified to allow it to distinguish parent ceftiofur from other antibiotics by incorporation of the enzymes penicillinase and cephalosporinase into the assay. the modified b. ste ... | 1995 | 7622714 |
| significance of phe-220 and gln-221 in the catalytic mechanism of farnesyl diphosphate synthase of bacillus stearothermophilus. | farnesyl diphosphate synthase [ec 2.5.1.10] from bacillus stearothermophilus was specifically altered at two amino acid residues by using site-directed mutagenesis. the highly conserved phe and gln residues at the sequential amino acid positions 220-221 in an upstream part of the putative substrate binding site were replaced with ala and glu, respectively. these mutageneses (f220a and q221e) resulted in 10(-5) and 10(-3) decreases in catalytic activity of farnesyl diphosphate synthesis, respecti ... | 1995 | 7626083 |
| homogeneity of the pyruvate dehydrogenase multienzyme complex from bacillus stearothermophilus. | the pyruvate dehydrogenase multienzyme complex was purified from bacillus stearothermophilus by means of six gel-filtration column chromatographies; once on cellulofine gcl-2000, twice on sepharose cl-2b, and three times on sephacryl s-500hr. the molecular size distribution of the complex was examined in detail by gel-filtration chromatography, analytical and sucrose-density ultracentrifugations, and dynamic light scattering. the complex was found to be homogeneous; a dimeric complex was undetec ... | 1995 | 7629008 |
| molecular cloning and nucleotide sequences of the genes for two essential proteins constituting a novel enzyme system for heptaprenyl diphosphate synthesis. | the genes encoding two dissociable components essential for bacillus stearothermophilus heptaprenyl diphosphate synthase (all-trans-hexparenyl-diphosphate:isopentenyl-diphosphate hexaprenyl-trans-transferase, ec 2.5.1.30) were cloned, and their nucleotide sequences were determined. sequence analyses revealed the presence of three open reading frames within 2,350 base pairs, designated as orf-1, orf-2, and orf-3 in order of nucleotide sequence, which encode proteins of 220, 234, and 323 amino aci ... | 1995 | 7629164 |
| co-overexpression of prlf increases cell viability and enzyme yields in recombinant escherichia coli expressing bacillus stearothermophilus alpha-amylase. | the effects on cloned amylase production of co-overexpression of prlf, a gene that appears to interact with the sec protein export machinery in escherichia coli, was investigated by comparing three expression systems: (i) a high copy number plasmid with the bacillus stearothermophilus alpha-amylase gene (amys) cloned with its promoter downstream of the lac promoter; (ii) a pbr322-based vector with amys under control of the indigenous bacillus promoter; and (iii) a temperature-inducible vector wi ... | 1995 | 7654312 |
| calculation of the molecular masses of two newly synthesized thermostable enzymes isolated from thermophilic microorganisms. | two thermostable enzymes synthesized by thermophilic microorganisms were isolated and purified. a thermostable beta-galactosidase was produced in a continuous fermentation process by bacillus stearothermophilus tp 32 as an intracellular enzyme. after applying different concentration procedures the raw extract enzyme was prepurified on a sephadex g-200 size exclusion column. the isolated beta-galactosidase fraction was then separated with hplc on a tsk g 3000 sw size exclusion column to determine ... | 1995 | 7655618 |
| a cluster of fever and hypotension on a surgical intensive care unit related to the contamination of plasma expanders by cell wall products of bacillus stearothermophilus. | to evaluate an outbreak of fever and hypotension after cardiac surgical procedures and the role of polygeline, a plasma expander. | 1995 | 7657985 |
| circular permutation within the coenzyme binding domain of the tetrameric glyceraldehyde-3-phosphate dehydrogenase from bacillus stearothermophilus. | a circularly permuted (cp) variant of the phosphorylating nad-dependent glyceraldehyde-3-phosphate dehydrogenase (gapdh) from bacillus stearothermophilus has been constructed with n- and c-termini created within the coenzyme binding domain. the cp variant has a kcat value equal to 40% of the wild-type value, whereas km and kd values for nad show a threefold decrease compared to wild type. these results indicate that the folding process and the conformational changes that accompany nad binding du ... | 1995 | 7663355 |
| structural determinants of the stability of thermolysin-like proteinases. | thermolysin is a member of a family of homologous proteinases which differ in their resistance to thermally induced unfolding and subsequent autolytic degradation. site-directed mutagenesis studies of the thermolysin-like proteinase (tlp) from bacillus stearothermophilus (tlp-ste) show that its reduced resistance to thermally induced autolysis, as compared to thermolysin, is due to only some of the 44 naturally occurring amino-acid differences between them. in fact tlp-ste becomes more resistant ... | 1995 | 7664094 |
| x-ray crystallography shows that translational initiation factor if3 consists of two compact alpha/beta domains linked by an alpha-helix. | the structures of the two domains of translational initiation factor if3 from bacillus stearothermophilus have been solved by x-ray crystallography using single wavelength anomalous scattering and multiwavelength anomalous diffraction. each of the two domains has an alpha/beta topology, with an exposed beta-sheet that is reminiscent of several ribosomal and other rna binding proteins. an alpha-helix that protrudes out from the body of the n-terminal domain towards the c-terminal domain suggests ... | 1995 | 7664745 |
| stress response in lactococcus lactis: cloning, expression analysis, and mutation of the lactococcal superoxide dismutase gene. | in an analysis of the stress response of lactococcus lactis, three proteins that were induced under low ph culture conditions were detected. one of these was identified as the lactococcal superoxide dismutase (soda) by n-terminal amino acid sequence analysis. the gene encoding this protein, designated soda, was cloned by the complementation of a soda sodb escherichia coli strain. the deduced amino acid sequence of l. lactis soda showed the highest degree of similarity to the manganese-containing ... | 1995 | 7665513 |
| thermophilic bacilli have split cytochrome b genes for cytochrome b6 and subunit iv. first cloning of cytochrome b from a gram-positive bacterium (bacillus stearothermophilus). | | 1995 | 7665630 |
| discovery of a ptshi operon, which includes a third gene (ptst), in the thermophile bacillus stearothermophilus. | the discovery of ptshi operon in bacillus stearothermophilus xl-65-6 coupled with our previous report of a cel operon (lai & ingram, j bacteriol 175, 6441-6450, 1993) demonstrates that this thermophilic organism contains all of the genes required for cellobiose uptake by the phosphoenolpyruvate-dependent phosphotransferase system (pts). genes encoding the two general pts proteins, hpr (ptsh) and enzyme i (ptsi), were cloned and sequenced. these form an operon which includes a third small gene (p ... | 1995 | 7670643 |
| interaction of component enzymes with the peripheral subunit-binding domain of the pyruvate dehydrogenase multienzyme complex of bacillus stearothermophilus: stoichiometry and specificity in self-assembly. | the interaction between the pyruvate decarboxylase (e1) component and a di-domain (lipoyl domain plus peripheral subunit-binding domain) from the dihydrolipoyl acetyltransferase (e2) component of the bacillus stearothermophilus pyruvate dehydrogenase multienzyme complex was investigated. only 1 mol of di-domain (binding domain) was bound to 1 mol of heterotetrameric e1 (alpha 2 beta 2) and the binding was without effect on the kinetic activity of e1. similarly, the di-domain bound to separate e1 ... | 1995 | 7702567 |
| improved specificity toward substrates with positively charged side chains by site-directed mutagenesis of the l-lactate dehydrogenase of bacillus stearothermophilus. | the substrate specificities of l-alpha-hydroxy acid dehydrogenases, including l-lactate dehydrogenases (l-ldh's), can often be quite broad. however, an ldh with high catalytic activity toward alpha-keto acids with positively charged side chains, such as those containing ammonium groups, has not been described, even though there is evidence from metabolic studies that a natural dehydrogenase with such activity might exist in nature. l-omega-amino-alpha-hydroxy acids are important intermediates in ... | 1995 | 7703235 |
| studies on thermophile products. x. further biological properties of isofatty acid-containing phosphatidylglycerol that enhances the induction of suppressor t cells. | isofatty acid-containing phosphatidylglycerol (fr. 7-c), isolated from bacillus stearothermophilus ubt8038, enhances the induction of concanavalin a (con a)-activated suppressor t (ts) cells in a dose dependent manner (0.01-1 microgram/ml). its further biological properties on mouse mixed lymphocyte reaction (mlr) has been demonstrated. fr. 7-c (0.01-1 microgram/ml) suppressed the mlr at 4 d in a dose-dependent manner when added at the start of splenocyte cultivation. moreover, fr. 7-c was effec ... | 1994 | 7703960 |
| effects of signal peptide mutations on processing of bacillus stearothermophilus alpha-amylase in escherichia coli. | bacillus stearothermophilus alpha-amylase has a signal peptide typical for proteins exported by gram-positive bacteria. there is only one signal peptidase processing site when the protein is exported from the original host, but when it is exported by escherichia coli, two alternative sites are utilized. site-directed mutagenesis was used to study the processing in e. coli. processing sites for 13 b. stearothermophilus alpha-amylases carrying mutations in their signal peptide were determined. pro ... | 1995 | 7711904 |
| analysis of a novel gene and beta-galactosidase isozyme from a psychrotrophic arthrobacter isolate. | we have characterized a new psychrotrophic arthrobacter isolate which produces beta-galactosidase isozymes. when dna from this isolate was transformed into an escherichia coli host, we obtained three different fragments, designated 12, 14, and 15, each encoding a different beta-galactosidase isozyme. the beta-galactosidase produced from fragment 12 was of special interest because the protein subunit was smaller (about 71 versus 116 kda) than those typically encoded by the lacz family. the isozym ... | 1995 | 7721689 |
| studies on thermophile products. xi. biological effect of antigen presenting inhibitor, isofatty acid-containing phosphatidylethanolamine, on mouse macrophages. | a new fraction, fr. 8-a, which consists of a phosphatidylethanolamine with c14:0-c18:0 isofatty acids was obtained from bacillus stearothermophilus ubt8038. the fraction inhibited major histocompatibility complex class ii (ia) antigen expression and antigen presentation on mouse macrophages. the effect of fr.8-a on macrophage functions related to antigen presentation was investigated. fr. 8-a increased arachidonate release, prostaglandin (pg) e2 release and nitrite production from peritoneal mac ... | 1994 | 7735194 |
| thermophilic bacilli have split cytochrome b genes for cytochrome b6 and subunit iv. first cloning of cytochrome b from a gram-positive bacterium (bacillus stearothermophilus). | the genes of bacillus stearothermophilus k1041 encoding cytochrome b(6) (bacillus cytochrome b is referred to as cytochrome b(6) for its resemblance to plastid b6) and subunit iv of the quinol:cytochrome c oxidoreductase (bc1 complex) were cloned and sequenced. for preparation of the probe for cloning, polymerase chain reaction was carried out using oligonucleotide mixtures targeting for n-terminal regions of cytochrome bc and subunit iv of the thermophilic bacillus ps3. the deduced amino acid s ... | 1995 | 7737998 |
| three-dimensional structure of a lipoyl domain from the dihydrolipoyl acetyltransferase component of the pyruvate dehydrogenase multienzyme complex of escherichia coli. | the structure of a lipoyl domain from the pyruvate dehydrogenase multienzyme complex of escherichia coli has been determined by means of nuclear magnetic resonance spectroscopy. a total of 549 nuclear overhauser effect distance restraints, 52 phi torsion angle restraints and 16 slowly exchanging amide protons were employed as input for the structure calculations. these were performed using a combined distance geometry-simulated annealing strategy. the domain is a hybrid between the n and c-termi ... | 1995 | 7739044 |
| characterization of the bacillus stearothermophilus br219 phenol hydroxylase gene. | the catabolic genes phea and pheb, coding for the conversion of phenol to catechol and catechol to 2-hydroxymuconic semialdehyde, respectively, have been cloned from bacillus stearothermophilus br219 into escherichia coli. following its localization on the 11-kb b. stearothermophilus dna insert by deletion and expression analysis, the phenol hydroxylase gene phea was subcloned as a 2-kb hindiii fragment, whose transformant expressed the enzyme after phenol induction and even more strongly after ... | 1995 | 7747948 |
| the effect of different water-insoluble anorganic salts on the resistance and storage time of bacillus stearothermophilus spores used for biological indicators. | the survival of bacillus stearothermophilus spores was investigated over 7 years. the spores were precipitated with 18 insoluble inorganic salts. there were hydroxides, carbonates, oxalates, phosphates, and sulfate of aluminium, barium, calcium, iron, magnesium, manganese, and tin. the stability of the spores to dry and moist heat was strongest in precipitates of barium and calcium salts. most phosphates and the heavy metals caused a rapid inactivation of spores. finally, the survival of the spo ... | 1994 | 7748440 |
| the ihf proteins of rhodobacter capsulatus and pseudomonas aeruginosa. | the binding properties of the two ihf consensus sequences present in the promoter region of the hydrogenase structural operon, hupsl, of rhodobacter capsulatus were studied by gel retardation assays using the heterodimeric ihf-like proteins isolated from r capsulatus, from pseudomonas aeruginosa and from escherichia coli. the three ihf proteins bound preferentially to the ihf consensus proximal to hups. the three-dimensional structure of r capsulatus ihf was modeled using a computer-based amino ... | 1994 | 7748939 |
| [the chemiklaven 7000/8000 on the test bench]. | sterilization of metal instruments in chemiclaves is undoubtedly the most protective mode of sterilization, because corrosion and formation of spots is minimal. in the past sterilization with chemiclaves was criticised, because of the emission of formaldehyde by older models and the questionable efficacy of formaldehyde sterilization for wrapped instruments. in the present investigation the capability of the newest chemiclaves (7000/8000) to sterilize dental instruments was investigated. to moni ... | 1995 | 7754333 |
| agarose gel electrophoretic detection of six beta-lactam antibiotic residues in milk. | an electrophoretic method coupled with bioautography was developed for detection and identification of penicillin g, ampicillin, amoxicillin, cloxacillin, cephapirin, and ceftiofur residues in milk. the method uses a 2% agarose gel for electrophoresis, an overlay of pm indicator agar seeded with bacillus stearothermophilus var. calidolactis, and incubation at 55 degrees c for 16-18 h. the new method separated and detected residues in milk at the levels of concern for the food and drug administra ... | 1995 | 7756879 |
| effect of rubber stopper composition, preservative pretreatment and rinse water temperature on the moist heat resistance of bacillus stearothermophilus atcc 12980. | bacillus stearothermophilus spores (liquid suspension) were inoculated onto rubber stoppers and exposed to sublethal steam sterilization cycles at 120 degrees c. the d-values were determined using the fraction-negative method. an increase in heat resistance (d-value) of 200%-400% was observed when the spore suspension was inoculated onto rubber stoppers. the d-values ranged from 4.90-6.96 minutes 120 degrees c. no significant effect was seen when different preservatives were added to the stopper ... | 1995 | 7757456 |
| enzymatic synthesis of a novel trisaccharide, glucosyl lactoside. | cyclomaltodextrin glucanotransferase from bacillus stearothermophilus produced a series of oligosaccharides by the transglycosylation reaction with cyclomaltohexaose as a glycosyl donor and d-lactose as its acceptor. the content of oligosaccharide a as the main transfer product was 22.1% of the total sugar. the content was increased to 34.1% by hydrolysis with glucoamylase. oligosaccharide a was isolated by column chromatography and crystallized. by chemical and enzymatic analyses, oligosacchari ... | 1993 | 7763423 |
| thermolabile alanine racemase from a psychotroph, pseudomonas fluorescens: purification and properties. | a psychotrophic bacterium that produces a thermolabile alanine racemase was isolated from raw milk, and identified as pseudomonas fluorescens tm5-2. the enzyme was purified to homogeneity from the cell extract, and characterized to be compared with enzymes from mesophiles (bacillus subtilis and salmonella typhimurium) and a thermophile (bacillus stearothermophilus). the enzyme has a molecular weight of about 76,000 and consists of two subunits identical in molecular weight (38,000). the enzyme c ... | 1993 | 7763424 |
| a bacillus stearothermophilus esterase produced by a recombinant bacillus brevis stabilized by sulfhydryl compounds. | | 1993 | 7763782 |
| evaluation of column flotation in the downstream processing of fermentation products: recovery of a genetically engineered alpha-amylase. | flotation is a simple, inexpensive, and versatile unit operation with a largely unexplored potential in biotechnology. there is a general lack of research concerning biotechnological applications in this area, especially in the recovery of fermentation products. moreover, the few reports in the literature do not consider the modern concept of column flotation as practiced in the mineral industry. we report herein the application of column flotation for the recovery of a bacillus stearothermophil ... | 1993 | 7763908 |
| effects of moranoline, 4-o-alpha-d-glucopyranosylmoranoline and their n-substituted derivatives on thermostability of cyclodextrin glycosyltransferase, glucoamylase, and beta-amylase. | in repeated glycosylmoranolines synthetic reaction at 55 degrees c, cyclodextrin glycosyltransferase (cgt-ase, ec 2.4.1.19) from bacillus stearothermophilus retained its activity for more than 600 days. a main stabilizing compound was found to be 4-o-alpha-d-glucopyranosylmoranoline. the thermostabilizing activities of moranoline, 4-o-alpha-d-glucopyranosylmoranoline, and their n-substituted derivatives were studied. moranoline and its n-substituted derivatives stabilized glucoamylase. 4-o-alpha ... | 1993 | 7764015 |
| efficient production of bacillus stearothermophilus alpha-amylase in bacillus brevis by altering its signal peptide. | to investigate the role of signal peptides in extracellular production in bacillus brevis, the bacillus stearothermophilus alpha-amylase signal peptide was systematically altered and the effects were analyzed in b. brevis. efficient extracellular production of the amylase in b. brevis was accomplished either by introducing point mutations at positions between -6 and -4 or by replacing the whole signal peptide with that of b. brevis middle wall protein. | 1993 | 7764020 |
| thermostable mutants of kanamycin nucleotidyltransferase are also more stable to proteinase k, urea, detergents, and water-miscible organic solvents. | a series of variants of kanamycin nucleotidyltransferase (kntase), isolated previously on the basis of enhanced thermostability by cloning and selection for enzymatic activity in the thermophile bacillus stearothermophilus, was used to systematically test the hypothesis that thermostable enzymes would also be more resistant to other forms of protein denaturation. the purified kntases were treated with proteinase k or assayed at 37 degrees c in the presence of urea, n-lauroylsarcosine, triton x-1 ... | 1993 | 7764052 |
| molecular cloning and sequencing of the gene for a thermostable n-carbamyl-l-amino acid amidohydrolase from bacillus stearothermophilus strain ns1122a. | the gene for n-carbamyl-l-amino acid amidohydrolase was cloned from bacillus stearothermophilus strain ns1122a into e. coli. this gene started with a ttg triplet and was predicted to encode a peptide of 409 amino acids, with a calculated molecular weight of 44,248. the deduced amino acid sequence shared moderate homology with that of the corresponding enzyme of pseudomonas sp. strain ns671. | 1993 | 7764340 |
| role of cysteine residues in esterase from bacillus stearothermophilus and increasing its thermostability by the replacement of cysteines. | bacillus stearothermophilus esterase contains two free cysteine residues at positions of 45 and 115, which react with sulfhydryl reagents resulting in a significant decrease in the enzymatic activity. to understand the role of the cysteine residues in catalytic regions of the esterase, the residues were replaced with serine or alanine by site-directed mutagenesis to construct four single-mutated enzymes (c45a, c45s, c115a, c115s) and two double-mutated ones (c45/115a and c45/115s). wild-type and ... | 1994 | 7764425 |
| engineering surface loops of proteins--a preferred strategy for obtaining new enzyme function. | a prerequisite for the rational redesign of enzymes is that altering amino acids in an attempt to obtain new biological function does not unexpectedly alter the globular, natural framework of the native protein on which the design is being executed. the results of combinatorial-mutagenesis strategies suggest that random variation of amino acid sequence is most easily tolerated at the solvent-exposed surfaces of a protein. this review analyses effective redesigns of bacillus stearothermophilus la ... | 1994 | 7764905 |
| cloning and expression of a pathway for benzene and toluene from bacillus stearothermophilus. | bacillus stearothermophilus strain br325 demonstrating broad aromatic substrate capability was isolated from petroleum-contaminated soil. the chromosomally-located aromatic pathway from this isolate was cloned into escherichia coli as a 32 kb insert in cosmid phc79, conferring growth on benzene, phenol, and toluene as sole carbon sources. | 1994 | 7765116 |
| a thermostable hydantoinase of bacillus stearothermophilus ns1122a: cloning, sequencing, and high expression of the enzyme gene, and some properties of the expressed enzyme. | a dna fragment containing the gene for a thermostable hydantoinase was cloned from a thermophile, bacillus stearothermophilus ns1122a in escherichia coli. nucleotide sequencing showed that the dna fragment contains one open reading frame, which is predicted to encode a peptide of 471 amino acids, with a calculated molecular weight of 51,724. when the hydantoinase gene was under the control of both the lpp promoter and the lac promoter-operator, and its expression was induced by isopropyl-1-thio- ... | 1994 | 7765480 |
| cloning of the gene encoding dna binding protein hu from bacillus stearothermophilus and its expression in escherichia coli. | the gene (hbst) encoding the dna binding protein hu from bacillus stearothermophilus was cloned, with the bacillus subtilis hu gene (hbsu) as a hybridization probe. the nucleotide sequence, which contains a ribosome binding site, a transcriptional termination signal, as well as the coding region, was analyzed by the dideoxy chain-termination method. the deduced amino acid sequence of an open reading frame was perfectly matched with that of b. stearothermophilus hu (bsthu) determined by the prote ... | 1995 | 7765961 |
| role of residue 161 in the allosteric transitions of two bacterial phosphofructokinases. | the loop between alpha-helix 6 and beta-strand f of the phosphofructokinase (pfk) from bacillus stearothermophilus is proposed to be important in the allosteric transition of the enzyme [schirmer, t., & evans, p.r. (1990) nature 343, 140-145]. except for residue 161, the amino acids within the loop are similar between b. stearothermophilus pfk (bspfk) and the pfk from escherichia coli (ecpfk). in the former enzyme, residue 161 is a glutamate, while in the latter it is a glutamine. we have used s ... | 1995 | 7766616 |
| stabilization of a ribosomal rna tertiary structure by ribosomal protein l11. | interactions between ribosomal protein l11 and a domain of large subunit rrna have been highly conserved and are essential for efficient protein synthesis. to study the effects of l11 on rrna folding, a homolog of the escherichia coli l11 gene has been amplified from bacillus stearothermophilus dna and cloned into a phage t7 polymerase-based expression system. the expressed protein is 93% homologous to the l11 homolog from bacillus subtilis, denatures at temperatures above 72 degrees c, and has ... | 1995 | 7783196 |
| determination of peptide regions exposed at the surface of the bacterial ribosome with antibodies against synthetic peptides. | we synthesized six peptides corresponding to regions that are predicted to be surface-exposed of the following ribosomal proteins: protein l2, positions (d263-k272); protein l5, positions (i136-g150); protein l25, positions (q75-d90); protein s3, positions (q222-k232) derived from escherichia coli; and protein l2, positions (k257-k275), and protein s3, positions (r130-t150) from bacillus stearothermophilus. these peptides were employed to raise ribosomal protein-cross-reactive antibodies. the an ... | 1995 | 7794529 |
| macromolecular recognition through electrostatic repulsion. | in the process of genetic translation, each aminoacyl-trna synthetase specifically aminoacylates its cognate trnas and rejects the 19 other species of trnas. a decrease in the specificity of this reaction can result in misincorporations of amino acids into proteins and be deleterious to the cell. in the case of tyrosyl-trna synthetase from bacillus stearothermophilus, the change of residue glu152 into ala results in erroneous interactions with non-cognate trnas. to analyse how glu152 contributes ... | 1995 | 7796819 |
| role of the conserved glycyl residues located at the active site of leucine dehydrogenase from bacillus stearothermophilus. | a tetrapeptide sequence, gly-gly-(gly/ala)-lys, containing a catalytically important lysyl residue, is highly conserved in nad(p)+-dependent amino acid dehydrogenases. to elucidate functional roles of the glycyl residues in this conserved sequence gly-77, gly-78, and gly-79 of the recombinant leucine dehydrogenase from bacillus stearothermophilus have been individually replaced with ala by site-directed mutagenesis. all of the mutant enzymes had michaelis constants for alpha-keto-iso-caproate an ... | 1994 | 7798175 |
| over-expression of membrane-bound cytochrome c-551 from thermophilic bacillus ps3 in bacillus stearothermophilus k1041. | cytochrome c-551 is a lipoprotein of about 10500 da, found in thermophilic bacillus ps3 grown under air-limited conditions. an expression vector was constructed from a structural gene of ps3 cytochrome c-551, synthetic oligonucleotide as a promoter for bacillus stearothermophilus and a shuttle vector for escherichia coli and b. stearothermophilus. the transformed cells of b. stearothermophilus k1041 expressed cytochrome c-551 as much as 5 nmol/mg membrane protein. the effects of over-expression ... | 1994 | 7803447 |
| studies on thermophile products. ix. isofatty acid-containing phosphatidylglycerol that enhances the induction of concanavalin a-activated suppressor t cells. | a new enhancer of the induction of concanavalin a (con a)-activated suppressor t (ts) cells has been demonstrated in the ethanolysate of bacillus stearothermophilus ubt8038. it was purified by successive silica gel column chromatographies and identified as phosphatidylglycerol with c14:0-c18:0 isofatty acids (fr. 7-c). mouse splenocytes activated with con a and fr. 7-c (0.01-1 microgram/ml) in vitro significantly suppressed the proliferative response of syngenic splenocytes by mitogen stimulatio ... | 1994 | 7841936 |
| c-terminal truncations of a thermostable bacillus stearothermophilus alpha-amylase. | a series of truncated proteins from a thermostable bacillus stearothermophilus alpha-amylase was prepared to study the importance of the extension in the c-terminus compared with other liquefying bacillus alpha-amylases. the mutations introducing new translation termination sites shortened the 515 amino acid residue-long wild type enzyme by 17, 32, 47, 73 or 93 residues. the longer the truncation, the lower the specific activity of the enzyme. only the two longest mutant proteins were active: th ... | 1994 | 7855141 |
| thermostable farnesyl diphosphate synthase of bacillus stearothermophilus: crystallization and site-directed mutagenesis. | the gene for thermostable farnesyl diphosphate synthase from bacillus stearothermophilus was cloned, sequenced, and overexpressed in escherichia coli. the synthase was purified to homogeneity and crystallized. the enzyme carried only two cysteine residues in contrast to its counterparts from other sources, which have four to six cysteine residues. either or both of the cysteine residues can be replaced with serine without causing a loss of the catalytic activity. the conserved arginine residue t ... | 1994 | 7856399 |
| improvement of thermal stability of subtilisin j by changing the primary autolysis site. | the thermostability of subtilisin j, an extracellular serine protease secreted from bacillus stearothermophilus, has been improved by changing the primary autolysis site of the asp-49 mutant protein. previously we have shown that the asp-49 mutant protein has proteolytic activity, but so unstable that it was primarily autolyzed in tyr-58-gln-59 peptide bond during cultivation (jang et al. biochim. biophys. acta. 1162, 233-235 1993). in the present study, to mitigate the autolytic degradation and ... | 1995 | 7857265 |
| solvent isotope effects and the nature of electrophilic catalysis in the action of the lactate dehydrogenase of bacillus stearothermophilus. | deuterium oxide at atom fractions of deuterium from 0.0 to 0.97 has an effect of less than 20% on the kinetic term kcat/kmb (believed to reflect the transition state for the hydride-transfer step) for the reduction of pyruvic acid by nadh at 55 degrees c, with catalysis by the tetrameric form of the lactate dehydrogenase of bacillus stearothermophilus. this observation suggests that the hydride-transfer event is not assisted by protonic bridging to the carbonyl group being reduced. the results a ... | 1994 | 7858977 |
| new shuttle vector for cloning in bacillus stearothermophilus. | cloning vector plasmid prp9 was constructed on the basis of the broad host-range plasmid plm6. prp9 was a small plasmid (2.9 kb), possessed a convenient polyrestriction site sequence and efficiently transformed bacillus subtilis, bacillus stearothermophilus and escherichia coli. furthermore, prp9 presented a very high segregational stability in bacillus hosts. also, the structural stability in bacillus strains, grown under selective pressure, of prp9 carrying a 3-kb fragment, was high. no single ... | 1994 | 7871236 |
| role of glycine 212 in the allosteric behavior of phosphofructokinase from bacillus stearothermophilus. | crystallographic studies indicate that the loop between alpha-helix 8 and beta-strand h (the 8h loop) which borders the effector site of bacillus stearothermophilus phosphofructokinase (bspfk) is involved in the allosteric mechanism of the enzyme [schirmer, t., and evans, p.r. (1990) nature 343, 140-145]. the residue at one end of this loop, glycine 212, has been proposed to be a pivot about which the loop hinges. using site-directed mutagenesis, glycine 212 was replaced with valine (g212v). ste ... | 1995 | 7873536 |
| a chimeric bacterial phosphofructokinase exhibits cooperativity in the absence of heterotropic regulation. | the phosphofructokinases (pfks) from the bacteria escherichia coli and bacillus stearothermophilus differ markedly in their regulation by atp. whereas e. coli pfk (ecpfk) is profoundly inhibited by atp, b. stearothermophilus pfk (bspfk) is only slightly inhibited. the structural basis for this difference could be closure of the active site via a conformational transition that occurs in the atp-binding domain of ecpfk, but is absent in bspfk. to investigate the role of this transition in atp inhi ... | 1995 | 7876126 |
| the crystal structure of holo-glyceraldehyde-3-phosphate dehydrogenase from the hyperthermophilic bacterium thermotoga maritima at 2.5 a resolution. | the crystal structure of holo-glyceraldehyde-3-phosphate dehydrogenase from the hyperthermophile thermotoga maritima was determined by patterson search methods using the known structure of the bacillus stearothermophilus enzyme. the structure was refined at a resolution of 2.5 a to an r-factor of 16.63% for 26289 reflections between 8.0 a an 2.5 a with f > 2 sigma(f). the crystallographic asymmetric unit contains two monomers related by approximate 2-fold symmetry and a tetramer is built up by c ... | 1995 | 7877172 |
| construction and characterization of chimeric enzyme consisting of an amino-terminal domain of phenylalanine dehydrogenase and a carboxy-terminal domain of leucine dehydrogenase. | phenylalanine dehydrogenase of thermoactinomyces intermedius acts preferentially on l-phenylalanine and l-tyrosine, whereas leucine dehydrogenase of bacillus stearothermophilus acts almost exclusively on l-leucine and some other branched-chain l-amino acids. the two enzymes share a sequence similarity (47%). aiming at elucidation of the mechanism of substrate recognition by the two amino acid dehydrogenases, we have genetically constructed a chimeric enzyme consisting of an n-terminal domain of ... | 1994 | 7883771 |
| purification and characterization of alpha-l-arabinofuranosidase from bacillus stearothermophilus t-6. | bacillus stearothermophilus t-6 produced an alpha-l-arabinofuranosidase when grown in the presence of l-arabinose, sugar beet arabinan, or oat spelt xylan. at the end of a fermentation, about 40% of the activity was extracellular, and enzyme activity in the cell-free supernatant could reach 25 u/ml. the enzymatic activity in the supernatant was concentrated against polyethylene glycol 20000, and the enzyme was purified eightfold by anion-exchange and hydrophobic interaction chromatographies. the ... | 1995 | 7887599 |
| microbiologic evaluation of a hydrogen peroxide sterilization system. | the reliability of chemical sterilizers (acetone and/or 30-percent hydrogen peroxide at 25 degrees c and at 60 degrees c) was tested against bacillus subtilis inoculated onto glass slides, commercial biological indicator discs (bacillus stearothermophilus and b. subtilis), and b. subtilis spore survival. acetone alone was not sporicidal. hydrogen-peroxide-sterilized glass slides were sterile after 5 minutes. the indicator discs required 25 minutes at 25 degrees c, and less than 3 minutes at 60 d ... | 1994 | 7898862 |
| structural and functional roles of the cysteine residues of bacillus stearothermophilus farnesyl diphosphate synthase. | p-(chloromercuri)benzoic acid inhibited the catalytic activity of bacillus stearothermophilus farnesyl diphosphate synthase (fpp synthase), which contains only two cysteine residues at positions 73 and 289. in order to explore the role of the cysteine residues, either or both of them were replaced with phenylalanine or serine. five mutant enzymes, c73f, c73s, c289f, c289s, and c73s-c289s, were overproduced in escherichia coli and purified to homogeneity. all of them were active as farnesyl dipho ... | 1994 | 7918490 |
| phylogenetic diversity in the genus bacillus and comparative ribosomal protein at-l30 analyses of the genus thermoactinomyces and relatives. | the ribosomal l30 proteins from strains of 27 species belonging to the genera bacillus, escherichia, staphylococcus, lactobacillus, leuconostoc and thermoactinomyces were analysed, together with at-l30 proteins from selected actinomycetes. the results of partial amino acid sequencing of l30 preparations revealed that the members of the genera escherichia, staphylococcus and thermoactinomyces were homogeneous within each genus. in contrast, phylogenetic diversity existed in the genus bacillus, wh ... | 1994 | 7921265 |
| properties of a pentapeptide inhibitor of peptidyltransferase that is essential for cat gene regulation by translation attenuation. | inducible chloramphenicol resistance genes cat and cmla are regulated by translation attenuation. for both genes, the leader codons that must be translated to deliver a ribosome to the induction site specify a peptide that inhibits peptidyltransferase in vitro. the antipeptidyltransferase activity of the peptides is thought to select the site of ribosome stalling that is essential for induction. using variations of the cat-86 leader-encoded 5-mer peptide mvktd, we demonstrate a correlation betwe ... | 1994 | 7928994 |
| feasibility of a combined carrier test for disinfectants: studies with a mixture of five types of microorganisms. | there is mounting concern regarding the efficacy of many germicides on the market because officially recognized germicidal tests for various classes of microorganisms vary widely and often lack reproducibility and proper quantitation. we report here a carrier method for simultaneously and quantitatively assessing the efficacy of liquid chemical germicides against a mixture of microorganisms of varying degrees of resistance. | 1994 | 7943926 |
| properties and active center of the thermostable branching enzyme from bacillus stearothermophilus. | although the branching enzyme (ec 2.4.1.18) is a member of the alpha-amylase family, the characteristics are not understood. the thermostable branching enzyme gene from bacillus stearothermophilus trbe14 was cloned and expressed in escherichia coli. the branching enzyme was purified to homogeneity, and various enzymatic properties were analyzed by our improved assay method. about 80% of activity was retained when the enzyme was heated at 60 degrees c for 30 min, and the optimum temperature for a ... | 1994 | 7944355 |
| studies on thermophile products. vii. effect of 1,3-di-14-methylpentadecanoyl glycerol and its related isofatty acids on t cell proliferation in vitro. | it has been found that bacillus stearothermophilus uk563-derived immunosuppressant fraction (fr. 5-b) consists of 1,3-diacylglycerols with saturated iso- and anteiso-type fatty acids (c14:0-c18:0) as major components. the compound, 1,3-di-14-methylpentadecanoyl glycerol (1,3-diiso c16:0 g), was synthesized and its effect on t cell proliferation was investigated together with its related isofatty acids. while 1,3-diiso c16:0 g, iso c16:0, iso c17:0, iso c17:0 methyl ester (ome) and anteiso c17:0 ... | 1994 | 7951153 |
| sequence of the cloned bsecim gene: m.bseci reveals high homology to m.baniii. | the bsecim gene, encoding m.bseci methyltransferase (mtase) from a bacillus stearothermophilus strain, has been previously cloned and expressed in escherichia coli [rina and bouriotis, gene 133 (1993) 91-94]. the nucleotide (nt) sequence of a 2357-bp bspmii-ecori fragment encoding bsecim has now been determined. the sequence predicts a mtase of 579 amino acids (aa), 66.7 kda. comparison of the deduced aa sequence of m.bseci with sequences of various mtases revealed a significant homology to m6a- ... | 1994 | 7959066 |
| comparative studies of s-layer proteins from bacillus stearothermophilus strains expressed during growth in continuous culture under oxygen-limited and non-oxygen-limited conditions. | the specific properties of s-layer proteins from three different bacillus stearothermophilus strains revealing oblique, square, or hexagonal lattice symmetry were preserved during growth in continuous culture on complex medium only under oxygen-limited conditions in which glucose was used as the sole carbon source. when oxygen limitation was relieved, amino acids became metabolized, cell density increased, and different s-layer proteins from wild-type strains became rapidly replaced by a new com ... | 1994 | 7961489 |
| [model studies of milk containing inhibitory substances. i. sensitivity of microbiological tests for detection of inhibitory substances and studies of turbidity changes in milk]. | in the present studies use was made of raw milk derived from a model farm in the olsztyn voivodeship. washing and washing-disinfecting agents: mirax, bis, radion, iosan cp, rudlak and ixi, as well as crystalline penicillin were added to milk. their lowest concentrations inhibiting growth of indicator strain (mic): bacillus stearothermophilus var. calidolactis c 953, were determined by two microbiological tests. moreover, the changes in light diffusion by milk, caused by the applied inhibitory su ... | 1993 | 7973409 |
| cloning and characterization of a cdna encoding phosphofructokinase from schistosoma mansoni. | schistosoma mansoni, a human parasitic worm, depends on anaerobic glycolysis as the main source of energy. phosphofructokinase (atp: d-fructose-6-phosphate 1-phosphotransferase, ec 2.7.1.11; pfk) limits the rate of glycolysis in these organisms and it has been found to be a target for some antischistosomal agents. a cdna clone from this parasite has been isolated and characterized. the cdna is 3046 base pairs long, contains an open reading frame of 2346 bp and codes for a deduced protein of 781 ... | 1994 | 7984171 |
| 1h, 13c, and 15n resonance assignments and secondary structure analysis of the hu protein from bacillus stearothermophilus using two- and three-dimensional double- and triple-resonance heteronuclear magnetic resonance spectroscopy. | nearly complete 1h, 13c, and 15n resonance assignments have been obtained for the protein hu from bacillus stearothermophilus (dimer, 19.5 kda) using double- and triple-resonance 2d and 3d nmr experiments. this has resulted in assignments of 91% of the observable protons, 98% of all 13c, and 92% of all 15n nuclei. noes obtained from a 3d time-shared noesy-(13c,15n)-hsqc spectrum, exchange data of amide protons, and chemical shifts of the 1h alpha, 1hn, 13c beta, 13c alpha, 13co, and 15n nuclei h ... | 1994 | 7993912 |
| evaluation of the antibacterial effects of intracanal nd:yag laser irradiation. | fifty canals of extracted single-rooted teeth were prepared to a size 50 master apical file, sterilized in ethylene oxide, and inoculated with a known quantity of bacillus stearothermophilus spores. five groups of 10 canals each were used. the control group received no treatment. the four treatment groups were exposed to pulsed nd:yag laser radiation or 0.5% naocl alone and in combination. the root canals were flushed with sterile distilled water to recover spores, and serial dilutions were incu ... | 1994 | 7996103 |
| effectiveness of sealed dental prophylaxis angles inoculated with bacillus stearothermophilus in preventing leakage. | it was the purpose of this in vitro investigation to evaluate the effectiveness of several brands of sealed, reusable prophylaxis angles to keep internal materials within the internal portions of the head of the prophylaxis angle, and not allowing contaminates to leak out. three brands of sealed, reusable dental prophylaxis angles were autoclaved and then taken apart under a biocontainment flow hood. testing conditions were designed to prevent a "worst case scenario" by inoculating dental prophy ... | 1994 | 7999287 |
| studies on thermophile products. viii. isolation of bacillus stearothermophilus ubt8038, a component that inhibits antigen presentation on mouse macrophages. | we have found a new compound from thermophile extracts which inhibits antigen presentation on mouse macrophages. the substance inhibits the expression of the class ii major histocompatibility molecule (ia). it was extracted from bacillus stearothermophilus ubt8038 and purified by silica gel column chromatography. the isolated inhibitor, fr. 8-a, was a phosphatidylethanolamine with isofatty acids and chemically different from any of the natural or synthetic products which have been reported to mo ... | 1994 | 8000370 |
| contribution of a buried aspartate residue towards the catalytic efficiency and structural stability of bacillus stearothermophilus lactate dehydrogenase. | the x-ray structure of lactate dehydrogenase (ldh) shows the side-chain carboxylate group of asp-143 to be buried in the hydrophobic interior of the enzyme, where it makes hydrogen-bonding interactions with both the side-chain hydroxyl group of ser-273 and the main-chain amide group of his-195. this is an unusual environment for a carboxylate side-chain as hydrogen bonding normally occurs with water molecules at the surface of the protein. a charged hydrogen-bonding interaction in the interior o ... | 1994 | 8002955 |
| cloning and expression in bacillus subtilis of the npr gene from bacillus thermoproteolyticus rokko coding for the thermostable metalloprotease thermolysin. | we report the isolation, cloning and expression, in bacillus subtilis, of the gene coding for thermolysin, a thermostable metalloprotease which is produced by bacillus thermoproteolyticus rokko. the nucleotide sequence has revealed that, like neutral proteases produced by other members of the bacillus species, thermolysin is probably produced as a preproenzyme carrying a typical n-terminal membrane signal sequence. further, the thermolysin gene shares a strong homology with two other previously ... | 1994 | 8002967 |
| a structural role for arginine in proteins: multiple hydrogen bonds to backbone carbonyl oxygens. | we propose that arginine side chains often play a previously unappreciated general structural role in the maintenance of tertiary structure in proteins, wherein the positively charged guanidinium group forms multiple hydrogen bonds to backbone carbonyl oxygens. using as a criterion for a "structural" arginine one that forms 4 or more hydrogen bonds to 3 or more backbone carbonyl oxygens, we have used molecular graphics to locate arginines of interest in 4 proteins: arg 180 in thermus thermophilu ... | 1994 | 8003972 |
| substitution of the amino acid at position 102 with polar and aromatic residues influences substrate specificity of lactate dehydrogenase. | the gln residue at amino acid position 102 of bacillus stearothermophilus lactate dehydrogenase was replaced with ser, thr, tyr, or phe to investigate the effect on substrate recognition. the q102s and q102t mutant enzymes were found to have a broader range of substrate specificity (measured by kcat/km) than the wild-type enzyme. however, it is evident that either ser or thr at position 102 are of a size able to accommodate a wide variety of substrates in the active site and substrate specificit ... | 1994 | 8011065 |
| electron cryomicroscopy of bacillus stearothermophilus 50 s ribosomal subunits crystallized on phospholipid monolayers. | 50 s ribosomal subunits from bacillus stearothermophilus have been crystallized as 2-dimensional periodic arrays on phospholipid monolayer films at the water-air interface. these crystals were preserved in vitreous ice and imaged with 100 kev electrons under low dose and low temperature conditions. the unit cell parameters of the crystals are a = 371.3(+/- 3.8) a, b = 152.3(+/- 1.6) a, gamma = 96.3(+/- 1.0) degrees. some of the image arrays of these crystals have twofold rotational symmetry with ... | 1994 | 8014989 |
| the purification, characterization, cloning and sequencing of the gene for a halostable and thermostable leucine dehydrogenase from thermoactinomyces intermedius. | leucine dehydrogenase has been purified to homogeneity from a moderate thermophilic actinomycete, thermoactinomyces intermedius ifo 14230. the enzyme can be stored without loss of its activity at a low temperature (e.g., 4 degrees c) for over two years. the enzyme was more thermostable at higher concentrations of salts such as nacl and kcl. it retained about 90% of activity on incubation at 70 degrees c for at least 40 min in the presence of 3 m nacl. the michaelis constants for nad, l-leucine, ... | 1994 | 8020469 |