| catalysis of tyrosyl-adenylate formation by the human tyrosyl-trna synthetase. | although the active site residues in the bacillus stearothermophilus and human tyrosyl-trna synthetases are largely conserved, several differences exist between the two enzymes. in particular, three amino acids that stabilize the transition state for the activation of tyrosine in b. stearothermophilus tyrosyl-trna synthetase (cys-35, his-48, and lys-233) are not present in the human enzyme. this raises the question of whether the activation energy for the tyrosine activation step is higher for t ... | 2002 | 11856731 |
| novel zinc-binding center and a temperature switch in the bacillus stearothermophilus l1 lipase. | the bacterial thermoalkalophilic lipases optimally hydrolyze saturated fatty acids at elevated temperatures. they also have significant sequence homology with staphylococcal lipases, and both the thermoalkalophilic and staphylococcal lipases are grouped as the lipase family i.5. we report here the first crystal structure of the lipase family i.5, the structure of a thermoalkalophilic lipase from bacillus stearothermophilus l1 (l1 lipase) determined at 2.0-a resolution. the structure is in a clos ... | 2002 | 11859083 |
| the effects of modifying the surface charge on the catalytic activity of a thermolysin-like protease. | the impact of long range electrostatic interactions on catalysis in the thermolysin-like protease from bacillus stearothermophilus was studied by analyzing the effects of inserting or removing charges on the protein surface. various mutations were introduced at six different positions, and double-mutant cycle analysis was used to study the extent to which mutational effects were interdependent. the effects of single point mutations on the k(cat)/k(m) were non-additive, even in cases where the po ... | 2002 | 11859085 |
| [comparative study of the m.bstf5i-1 and m.bstf5i-3 dna methyltransferases from the bacillus stearothermophilus f5 restriction-modification system]. | the bstf5i restriction-modification system from bacillus stearothermophilus f5, unlike all known restriction-modification systems, contains three genes encoding dna methyltransferases. in addition to revealing two dna methylases responsible for modification of adenine in different dna strands, it has been first shown that one bacterial cell has two dna methylases, m.bstf5i-1 and m.bstf5i-3, with similar substrate specificity. the boundaries of the gene for dna methyltransferase m.bstf5i-1 have b ... | 2002 | 11862704 |
| on the interaction of ribosomal protein l5 with 5s rrna. | ribosomal protein l5, a 5s rrna binding protein in the large subunit, is composed of a five-stranded antiparallel beta-sheet and four alpha-helices, and folds in a way that is topologically similar to the ribonucleprotein (rnp) domain [nakashima et al., rna 7, 692-701, 20011. the crystal structure of ribosomal protein l5 (bstl5) from bacillus stearothermophilus suggests that a concave surface formed by an anti-parallel beta-sheet and long loop structures are strongly involved in 5s rrna binding. ... | 2002 | 11866091 |
| [m.bstf5i-4, the forth dna methyltransferase of bstf5i restriction-modification system from bacillus stearothermophilus f5]. | the fourth dna-methyltransferase of the bstf5i restriction-modification (rm) system from bacillus stearothermophilus f5 (m.bstf5i-4) was discovered, which modifies the adenine residue within the upper strand of the recognition site 5'-ggatg-3'/5'-catcc-3'. thus, unlike other known rm systems, the bstf5i rm system comprises four genes encoding dna-methyltransferases, three of which possess the same substrate specificity and methylate adenine within the 5'-ggatg sequence. the english version of th ... | 2002 | 11875980 |
| functional grouping of thermophilic bacillus strains using amplification profiles of the 16s-23s internal spacer region. | molecular and biochemical assays were used to determine the identification of thermophilic bacilli isolated from new zealand milk powder. one hundred and forty one isolates of thermophilic bacilli were classified into six species using biochemical profiles. geobacillus stearothermophilus represented 56% of the isolates. all isolates were also analysed by randomly amplified polymorphic dna (rapd) analysis, with 45 types identified. amplification of the 16s-23s rdna internal spacer region produced ... | 2001 | 11876361 |
| crystal structure of binary and ternary complexes of serine hydroxymethyltransferase from bacillus stearothermophilus: insights into the catalytic mechanism. | serine hydroxymethyltransferase (shmt), a member of the alpha-class of pyridoxal phosphate-dependent enzymes, catalyzes the reversible conversion of serine to glycine and tetrahydrofolate to 5,10-methylene tetrahydrofolate. we present here the crystal structures of the native enzyme and its complexes with serine, glycine, glycine, and 5-formyl tetrahydrofolate (fthf) from bacillus stearothermophilus. the first structure of the serine-bound form of shmt allows identification of residues involved ... | 2002 | 11877399 |
| the thermostability of dna-binding protein hu from mesophilic, thermophilic, and extreme thermophilic bacteria. | based on primary structure comparison between four highly homologous dna-binding proteins (hus) displaying differential thermostability, we have employed in vitro site-directed mutagenesis to decipher their thermostability mechanism at the molecular level. the contribution of the 11 amino acids that differ between the thermophilic hubst from bacillus stearothermophilus (tm = 61.6 degrees c) and the mesophilic hubsu from bacillus subtilis (tm = 39.7 degrees c) was evaluated by replacing these ami ... | 2002 | 11878558 |
| modulation of cyclizing activity and thermostability of cyclodextrin glucanotransferase and its application as an antistaling enzyme. | cyclodextrin glucanotransferase from bacillus stearothermophilus et1 (cgtase et1) is a potential antistaling enzyme with cyclodextrin (cd)-forming activity. to reduce cyclization activity of cgtase et1, phenylalanine residues at 191 and 255 were replaced with a glycine (f191g-cgtase et1) and an isoleucine (f255i-cgtase et1), respectively. temperature optima of both mutant enzymes were lower than that of the wild-type. cyclization activities of both mutants decreased dramatically, but f255i-cgtas ... | 2002 | 11879012 |
| exposure of microorganisms to simulated extraterrestrial space ecology. | spores of five test organisms, bacillus subtilis var. niger, bacillus megaterium, bacillus stearothermophilus, clostridium sporogenes and aspergillus niger and soils were exposed, while under ultra high vacuum to temperatures of from -190 degrees c to +170 degrees c for 45 days. up to a temperature of 25 degrees c no loss in viability of the test spores were noted when compared to original populations maintained at room temperature at atmospheric pressure over a desiccant. at elevated temperatur ... | 1964 | 11883445 |
| an emission pattern of a thermophilic bacteria attached to or imbedded in porous supports. | there are many problems with thermophilic bacteria contamination of milk in the dairy industry. this is, in part, a result of fouling by milk components on stainless steel surfaces, which provide good harboring facilities for these bacteria to attach, imbed and grow. the interactions between milk fouling and bacteria deposited in or on the fouling deposit therefore become important issues. there have been a number of previous studies on the biofilm development in dairy processing plants. here, a ... | 2002 | 11883671 |
| in situ decontamination of medical wastes using oxidative agents: a 16-month study in a polyvalent intensive care unit. | over a 16-month period from september 1997 to december 1998, a prospective study was made of an on-site treatment of medical wastes in a 10-bed intensive care unit. first, the wastes were ground and then, a high concentration of ozone in air was repeatedly injected into the ground wastes. the study analysed the practical application of the system and its microbiological efficiency. inactivation experiments were made with reference strains of staphylococcus aureus, enterococcus hirae, pseudomonas ... | 2002 | 11886197 |
| reaction mechanism of alanine racemase from bacillus stearothermophilus: x-ray crystallographic studies of the enzyme bound with n-(5'-phosphopyridoxyl)alanine. | the crystal structures of alanine racemase bound with reaction intermediate analogs, n-(5'-phosphopyridoxyl)-l-alanine (plp-l-ala) and n-(5'-phosphopyridoxyl)-d-alanine (plp-d-ala), were determined at 2.0-a resolution with the crystallographic r factor of 17.2 for plp-l-ala and 16.9 for plp-d-ala complexes. they were quite similar not only to each other but also to the structure of the native pyridoxal 5'-phosphate (plp)-form enzyme; root mean square deviations at calpha among the three structur ... | 2002 | 11886871 |
| glycon specificity profiling of alpha-glucosidases using monodeoxy and mono-o-methyl derivatives of p-nitrophenyl alpha-d-glucopyranoside. | hydrolysis of probe substrates, eight possible monodeoxy and mono-o-methyl analogs of p-nitrophenyl alpha-d-glucopyranoside (pnp alpha-d-glc), modified at the c-2, c-3, c-4, and c-6 positions, was studied as part of investigations into the glycon specificities of seven alpha-glucosidases (ec 3.2.1.20) isolated from saccharomyces cerevisiae, bacillus stearothermophilus, honeybee (two enzymes), sugar beet, flint corn, and aspergillus niger. the glucosidases from sugar beet, flint corn, and a. nige ... | 2002 | 11909596 |
| posttranscriptional modifications in the a-loop of 23s rrnas from selected archaea and eubacteria. | posttranscriptional modifications were mapped in helices 90-92 of 23s rrna from the following phylogenetically diverse organisms: haloarcula marismortui, sulfolobus acidocaldarius, bacillus subtilis, and bacillus stearothermophilus. helix 92 is a component of the ribosomal a-site, which contacts the aminoacyl-trna during protein synthesis, implying that posttranscriptional modifications in helices 90-92 may be important for ribosome function. rna fragments were isolated from 23s rrna by site-dir ... | 2002 | 11911366 |
| bacillus stearothermophilus neopullulanase selective hydrolysis of amylose to maltose in the presence of amylopectin. | the specificity of bacillus stearothermophilus trs40 neopullulanase toward amylose and amylopectin was analyzed. although this neopullulanase completely hydrolyzed amylose to produce maltose as the main product, it scarcely hydrolyzed amylopectin. the molecular mass of amylopectin was decreased by only one order of magnitude, from approximately 10(8) to 10(7) da. furthermore, this neopullulanase selectively hydrolyzed amylose when starch was used as a substrate. this phenomenon, efficient hydrol ... | 2002 | 11916682 |
| potassium functionally replaces the second lysine of the kmsks signature sequence in human tyrosyl-trna synthetase. | unlike their bacterial homologues, a number of eukaryotic tyrosyl-trna synthetases require potassium to catalyze the aminoacylation reaction. in addition, the second lysine in the class i-specific kmsks signature motif is absent from all known eukaryotic tyrosyl-trna synthetase sequences, except those of higher plants. this lysine, which is the most highly conserved residue in the class i aminoacyl-trna synthetase family, has been shown to interact with the pyrophosphate moiety of the atp substr ... | 2002 | 11927599 |
| a recombinant bacterial cell surface (s-layer)-major birch pollen allergen-fusion protein (rsbsc/bet v1) maintains the ability to self-assemble into regularly structured monomolecular lattices and the functionality of the allergen. | the mature crystalline bacterial cell surface (s-layer) protein sbsc of bacillus stearothermophilus atcc 12980 comprises amino acids 31-1099 and assembles into an oblique lattice type. as the deletion of up to 179 c-terminal amino acids did not interfere with the self-assembly properties of sbsc, the sequence encoding the major birch pollen allergen (bet v1) was fused to the sequence encoding the truncated form rsbsc(31-920). the s-layer fusion protein, termed rsbsc/bet v1, maintained the abilit ... | 2002 | 11932495 |
| the identification of the acid-base catalyst of alpha-arabinofuranosidase from geobacillus stearothermophilus t-6, a family 51 glycoside hydrolase. | the alpha-l-arabinofuranosidase from geobacillus stearothermophilus t-6 (abfa t-6) belongs to the retaining family 51 glycoside hydrolases. the conserved glu175 was proposed to be the acid-base catalytic residue. abfa t-6 exhibits residual activity towards aryl beta-d-xylopyranosides. this phenomenon was used to examine the catalytic properties of the putative acid-base mutant e175a. data from kinetic experiments, ph profiles, azide rescue, and the identification of the xylopyranosyl azide produ ... | 2002 | 11943144 |
| glyceraldehyde-3-phosphate dehydrogenase from bacillus stearothermophilus. | | 1971 | 11945671 |
| tosylphenylalanyl chloromethane-inhibitor of complex of s(1)s(3)-factors in cell-free protein-synthetizing system from bacillus stearothermophilus. | | 1971 | 11946069 |
| comparative studies on the isoleucyl-trna synthetases from bacillus stearothermophilus and escherichia coli: ii. the effect of magnesium ions in the transacylation reaction. | | 1971 | 11946158 |
| neutral proteases with different thermostabilities from a facultative strain of bacillus stearothermophilus grown at 40 degrees and at 50 degrees. | | 1972 | 11946772 |
| arginyl-trna synthetase from bacillus stearothermophilus: heat inactivation and substrate induced protection. | | 1973 | 11946943 |
| comparative studies on the isoleucyl- and leucyl-trna synthetases from bacillus stearothermophilus and escherichia coli: thermal stability of the aminoacyladenylate-enzyme complexes. | | 1969 | 11947192 |
| some properties of the leucine-specific trna's from bacillus stearothermophilus. | | 1969 | 11947294 |
| a novel fluorescence competitive assay for glucose determinations by using a thermostable glucokinase from the thermophilic microorganism bacillus stearothermophilus. | we describe the use of a thermostable glucokinase in a novel competitive fluorescence assay for glucose. glucokinase from bacillus stearothermophilus (bsgk) was found to retain enzymatic activity in solution for over 20 days. the single cysteine residue in bsgk, which is near the active site, was labeled with a fluorescent probe, 2-(4-iodoacetamidoanilino)naphthalene-6-sulfonic acid. the ans-labeled bsgk displayed a modest 25% decrease in the emission intensity upon binding glucose but no change ... | 2002 | 11950213 |
| crystal structure of the bacillus stearothermophilus anti-sigma factor spoiiab with the sporulation sigma factor sigmaf. | cell type-specific transcription during bacillus sporulation is established by sigmaf. spoiiab is an anti-sigma that binds and negatively regulates sigmaf, as well as a serine kinase that phosphorylates and inactivates the anti-anti-sigma spoiiaa. the crystal structure of sigmaf bound to the spoiiab dimer in the low-affinity, adp form has been determined at 2.9 a resolution. spoiiab adopts the ghkl superfamily fold of atpases and histidine kinases. a domain of sigmaf contacts both spoiiab monome ... | 2002 | 11955433 |
| thermodynamic analysis of the binding of component enzymes in the assembly of the pyruvate dehydrogenase multienzyme complex of bacillus stearothermophilus. | the peripheral subunit-binding domain (psbd) of the dihydrolipoyl acetyltransferase (e2, ec 2.3.1.12) binds tightly but mutually exclusively to dihydrolipoyl dehydrogenase (e3, ec 1.8.1.4) and pyruvate decarboxylase (e1, ec 1.2.4.1) in the pyruvate dehydrogenase multienzyme complex of bacillus stearothermophilus. isothermal titration calorimetry (itc) experiments demonstrated that the enthalpies of binding (deltah degrees ) of both e3 and e1 with the psbd varied with salt concentration, temperat ... | 2002 | 11967366 |
| cooperative action of alpha-glucanotransferase and maltogenic amylase for an improved process of isomaltooligosaccharide (imo) production. | maltogenic amylase and alpha-glucanotransferase (alpha-gtase) were employed in an effort to develop an efficient process for the production of isomaltooligosaccharides (imos). bacillus stearothermophilus maltogenic amylase (bsma) and alpha-gtase from thermotoga maritima were overexpressed in escherichia coli using overexpression vectors. an imo mixture containing 58% of various imos was produced from liquefied corn syrup by the hydrolyzing and transglycosylation activities of bsma alone. when bs ... | 2002 | 11982404 |
| modeling and kinetic analysis of the reaction system using whole cells with separately and co-expressed d-hydantoinase and n-carbamoylase. | we developed a kinetic model that describes a heterogeneous reaction system for the production of d-p-hydroxyphenylglycine from d,l-p-hydroxyphenyl-hydantoin using d-hydantoinase of bacillus stearothermophilus sd1 and n-carbamoylase of agrobacterium tumefaciens nrrl b11291. as a biocatalyst, whole cells with separately or co-expressed enzymes were used. the reaction system involves dissolution of substrate particles, enzymatic conversion, racemization of the l-form substrate, and transfer of the ... | 2002 | 12001170 |
| enhancement of proteolytic enzyme activity excreted from bacillus stearothermophilus for a thermophilic aerobic digestion process. | proteolysis is one of the main enzymatic reactions involved in waste activated sludge (was) digestion. in this study, proteases excreted from bacillus stearothermophilus (atcc 31197) were classified, and an enhancement of protease activity was achieved using economical chemical additives for was digestion. proteases excreted from b. stearothermophilus were classified into two families: serine and metallo-proteases. various metal ions were investigated as additives which could potentially enhance ... | 2002 | 12003317 |
| requirement for c-terminal extension to the rna binding domain for efficient rna binding by ribosomal protein l2. | ribosomal protein l2 is a primary 23s rrna binding protein in the large ribosomal subunit. we examined the contribution of the n- and c-terminal regions of bacillus stearothermophilus l2 (bstl2) to the 23s rrna binding activity. the mutant desn, in which the n-terminal 59 residues of bstl2 were deleted, bound to the 23s rrna fragment to the same extent as wild type bstl2, but the mutation desc, in which the c-terminal 74 amino acid residues were deleted, abolished the binding activity. these obs ... | 2002 | 12005072 |
| structure and dynamics of the anticodon arm binding domain of bacillus stearothermophilus tyrosyl-trna synthetase. | the structure of a recombinant protein, tyrrs(delta4), corresponding to the anticodon arm binding domain of bacillus stearothermophilus tyrosyl-trna synthetase, has been solved, and its dynamics have been studied by nuclear magnetic resonance (nmr). it is the first structure described for such a domain of a tyrosyl-trna synthetase. it consists of a five-stranded beta sheet, packed against two alpha helices on one side and one alpha helix on the other side. a large part of the domain is structura ... | 2002 | 12005430 |
| modification of ascorbic acid using transglycosylation activity of bacillus stearothermophilus maltogenic amylase to enhance its oxidative stability. | ascorbic acid (1), a natural antioxidant, was modified by employing transglycosylation activity of bacillus stearothermophilus maltogenic amylase with maltotriose and acarbose as donor molecules to enhance its oxidative stability. the transglycosylation reaction with maltotriose as donor created mono- and di-glycosyl transfer products with an alpha-(1,6)-glycosidic linkage. in addition, two acarviosine-glucosyl transfer products were generated when transglycosylation was performed with acarbose ... | 2002 | 12010003 |
| isolation of chimaeric forms of elongation factor ef-tu by affinity chromatography. | six different recombinant chimaeric forms of a three-domain protein, proteosynthetic elongation factor tu (ef-tu), composed of domains of ef-tu of mesophilic (escherichia coli) and thermophilic (bacillus stearothermophilus) origin as well as free n-terminal domains of ef-tu, and the whole recombinant ef-tus of both organisms were prepared and isolated by the gst (glutathione s-transferase) fusion technology. several modifications in the standard isolation and purification procedures are describe ... | 2002 | 12013219 |
| comparison of the catalytic roles played by the kmsks motif in the human and bacillus stearothermophilus trosyl-trna synthetases. | the class i aminoacyl-trna synthetases are characterized by two signature sequence motifs, "high" and "kmsks." in bacillus stearothermophilus tyrosyl-trna synthetase, the kmsks motif (230kfgkt234) has been shown to stabilize the transition state for tyrosine activation through interactions with the pyrophosphate moiety of atp. in most eukaryotic tyrosyl-trna synthetases, the second lysine in the kmsks motif is replaced by a serine or an alanine residue. recent kinetic studies indicate that potas ... | 2002 | 12016229 |
| the effect of bioindicator preparation and storage on thermal resistance of bacillus stearothermophilus spores. | paper strips inoculated with spores of bacillus stearothermophilus atcc 7953 were conventionally dried (lot 1) and lyophilized (lot 2); stored in defined environments of 32 and 86% relative humidity at 10, 25 and 33 degrees c for 210 d; and submitted to moist heat treatments at 121 degrees c. a significant decrease in thermal resistance from initial starting levels was found for lyophilized bioindicators stored at 86% relative humidity. the respective average d121 degrees c values were 1.55+/-0. ... | 2002 | 12018279 |
| the effect of composition of parenteral solution on the thermal resistance of bacillus stearothermophilus and bacillus subtilis spores. | large-volume parenteral solutions were submitted to heat treatments after being inoculated with bacillus stearothermophilus atcc 7953 (tr = 121 degrees c) and bacillus subtilis atcc 9372 (tr = 104.5 degrees c) spores. the average decimal reduction time for b. stearothermophilus ranged from a d121 degrees c value of 1.31 to 3.14 min, in glucophysiologic and ringer's solutions respectively. for b. subtilis, d104.5 degrees c value increased from 0.69 to 1.37 min, in ringer's (ph=5.91) and 50% gluco ... | 2002 | 12018280 |
| transition state stabilization by the n-terminal anticodon-binding domain of lysyl-trna synthetase. | lysyl-trna synthetase from bacillus stearothermophilus (b.s. lysrs) (ec ) catalyzes aminoacylation of trna(lys) with l-lysine, in which l-lysine was first activated with atp to yield an enzyme (lysyladenylate complex), and then the lysine molecule was transferred from the complex to trna(lys). b.s. lysrs is a homodimeric enzyme with a subunit that consists of two domains, an n-terminal trna anticodon-binding domain (tab-nd: ser(1)-pro(144)) and a c-terminal class ii-specific catalytic domain (ca ... | 2002 | 12019264 |
| thermoadaptation of alpha-galactosidase agab1 in thermus thermophilus. | the evolutionary potential of a thermostable alpha-galactosidase, with regard to improved catalytic activity at high temperatures, was investigated by employing an in vivo selection system based on thermophilic bacteria. for this purpose, hybrid alpha-galactosidase genes of agaa and agab from bacillus stearothermophilus kve39, designated agaa1 and agab1, were cloned into an autonomously replicating thermus vector and introduced into thermus thermophilus of1053gd (deltaagat) by transformation. th ... | 2002 | 12029056 |
| homology modeling of bacillus subtilis tryptophanyl-trna synthetase. | tryptophanyl-trna synthetase (trprs) plays a pivotal role in protein synthesis. however, till now no stereostructural data of bacillus subtilis trprs were reported. here, by using the homology modeling using bacillus stearothermophilus trprs as a template, it is demonstrated that the synthetase has 16alpha helices and 5beta sheets. the only tryptophan trp(92) is located on the interface of subunits. also the modeling presents the ligand binding site, active site and the putative binding of trna( ... | 2001 | 12035063 |
| thermal unfolding used as a probe to characterize the intra- and intersubunit stabilizing interactions in phosphorylating d-glyceraldehyde-3-phosphate dehydrogenase from bacillus stearothermophilus. | tetrameric phosphorylating glyceraldehyde-3-phosphate dehydrogenase (gapdh) from bacillus stearothermophilus can be described as a dimer of dimers with three nonequivalent interfaces. to investigate the contribution of intra- and intersubunit interactions to gapdh thermostability, 10 residues located either at the cofactor domain (amino acids 1-148 and 313-333) or at the catalytic domain (amino acids 149-312) were mutated and the thermal unfolding of the mutants was studied by differential scann ... | 2002 | 12056886 |
| microwave-assisted rapid characterization of lipase selectivities. | a rapid screening procedure for characterization of lipase selectivities using microwaves was developed. the rate of reaction of various commercial lipases (porcine pancreas, mucor miehei, candida rugosa, pseudomonas cepacia) as well as lipases from laboratory isolates-bacillus stearothermophilus and burkholderia cepacia rgp-10 for triolein hydrolysis was 7- to 12-fold higher in a microwave oven as compared to that by ph stat. the esterification of sucrose/methanol and ascorbic acid with differe ... | 2002 | 12062110 |
| identification by saturation mutagenesis of a single residue involved in the alpha-galactosidase agab regioselectivity. | the alpha-galactosidase agab of bacillus stearothermophilus displays a major 1,6 and a minor 1,3 regioselectivity. the wild-type enzyme was subjected to directed evolution (random mutagenesis and in vitro recombination) using a double screening strategy based on the elimination of the 1,6 regioselectivity and the analysis by tlc of the transglycosylation products. one of the agab mutants (e500) exhibited a new 1,2 regioselectivity and a rather high level of transglycosylation. the corresponding ... | 2001 | 12084981 |
| overexpression and characterization of dimeric and tetrameric forms of recombinant serine hydroxymethyltransferase from bacillus stearothermophilus. | serine hydroxymethyltransferase (shmt), a pyridoxal-5' -phosphate (plp) dependent enzyme catalyzes the interconversion of l-ser and gly using tetrahydrofolate as a substrate. the gene encoding for shmt was amplified by pcr from genomic dna of bacillus stearothermophilus and the pcr product was cloned and overexpressed in escherichia coli. the purified recombinant enzyme was isolated as a mixture of dimer (90%) and tetramer (10%). this is the first report demonstrating the existence of shmt as a ... | 2002 | 12089472 |
| an engineered escherichia coli tyrosyl-trna synthetase for site-specific incorporation of an unnatural amino acid into proteins in eukaryotic translation and its application in a wheat germ cell-free system. | tyrosyl-trna synthetase (tyrrs) from escherichia coli was engineered to preferentially recognize 3-iodo-l-tyrosine rather than l-tyrosine for the site-specific incorporation of 3-iodo-l-tyrosine into proteins in eukaryotic translation systems. the wild-type tyrrs does not recognize 3-iodo-l-tyrosine, because of the bulky iodine substitution. on the basis of the reported crystal structure of bacillus stearothermophilus tyrrs, three residues, y37, q179, and q195, in the l-tyrosine-binding site wer ... | 2002 | 12097643 |
| cloning, expression, characterization and application of bst dna polymerase large fragment. | dna sequencing using thermostable dna polymerase is very valuable in molecular biology. from a specific strain of bacillus stearothermophilus, the gene of the bst dna polymerase large fragment which had no 5'-3' exonuclease activity was cloned and recombined into an expression vector pyz23,and the constructed plasmid was introduced into escherichia coli jf1125,then the expressed protein was isolated and purified. the genetic engineered product shows characteristics similar with the purified natu ... | 1999 | 12114989 |
| immobilized bacterial spores for use as bioindicators in the validation of thermal sterilization processes. | spores of bacillus subtilis atcc 6051 and bacillus stearothermophilus nctc 10003 were immobilized in monodisperse alginate beads (diameter, 550 microm +/- 5%), and the capacity of the immobilized bioindicators to provide accurate and reliable f-values for sterilization processes was studied. the resistance of the beads to abrasion and heat was strong enough to ensure total retention of the bioindicators in the beads in a sterilization cycle. d- and z-values for free spores were identical to thos ... | 2002 | 12117247 |
| crystal structure of d-hydantoinase from bacillus stearothermophilus: insight into the stereochemistry of enantioselectivity. | industrial production of antibiotics, such as semisynthetic penicillins and cephalosporins, requires optically pure d-p-hydroxylphenylglycine and its derivatives as important side-chain precursors. to produce optically pure d-amino acids, microbial d-hydantoinase (e.c. 3.5.2.2) is used for stereospecific hydrolysis of chemically synthesized cyclic hydantoins. we report the apo-crystal structure of d-hydantoinase from b. stearothermophilus sd1 at 3.0 a resolution. the structure has a classic tim ... | 2002 | 12135362 |
| improved partitioning in aqueous two-phase system of tyrosine-tagged recombinant lactate dehydrogenase. | the partitioning of bacillus stearothermophilus lactate dehydrogenase (ldh) in an aqueous two-phase system was studied. particularly, the influence of tyrosine tags on the partitioning was evaluated. the hydrophobic effect, caused by the addition of tyrosine residues, was determined in a system based on dextran and the thermoseparating ethylene oxide-propylene oxide random copolymer (eo30po70). five different ldh variants were constructed with n-terminal tags containing tyrosines (y3 and y6), ty ... | 2002 | 12135559 |
| boilysin and thermolysin in dipeptide synthesis: a comparative study. | boilysin (bln) is an engineered, highly thermostable neutral protease from bacillus stearothermophilus. its high resistance is based on the stabilization of a surface loop (amino acid residues 55-69) by eight amino acid exchanges, including the introduction of a disulphide bond. in the present study, bln was compared with the well-known and structurally related thermolysin (from b. thermoproteolyticus) with respect to their dipeptide- synthetic properties. the synthesis of the aspartame precurso ... | 2002 | 12149125 |
| overexpression, purification and characterization of thermostable catechol 2,3-dioxygenase. | catechol 2,3-dioxygenase(ec 1.13.11.2) from bacillus stearothermophilus has been shown to be highly thermostable. in order to obtain sufficient enzyme for its characterization, and to analyze the molecular basis of its intrinsic stability, the gene coding for this enzyme was sub-cloned and overexpressed in e. coli. after heat denaturation, ammonium sulfate fractionation, deae-52 ion-exchange chromatography and phenyl-sepharose cl-4b hydrophobic chromatography, the enzyme was purified to homogene ... | 1998 | 12167992 |
| identification of key amino acid residues in the assembly of enzymes into the pyruvate dehydrogenase complex of bacillus stearothermophilus: a kinetic and thermodynamic analysis. | structural studies have shown that electrostatic interactions play a major part in the binding of dihydrolipoyl dehydrogenase (e3) to the peripheral subunit-binding domain (psbd) of the dihydrolipoyl acyltransferase (e2) in the assembly of the pyruvate dehydrogenase multienzyme complex of bacillus stearothermophilus. the binding is characterized by a small, unfavorable enthalpy change (deltah degrees = +2.2 kcal/mol) and a large, positive entropy change (tdeltas degrees = +14.8 kcal/mol). the co ... | 2002 | 12173931 |
| expression of bacillus stearothermophilus lv cadmium resistance genes in escherichia coli causes hypersensitivity to cadmium chloride. | determination of the nucleotide sequence of a 4.5-kb chromosomal dna fragment of bacillus stearothermophilus lv revealed two open reading frames (orfs) of 121 and 727 amino acids (aa) that exhibit a high degree of similarity with the cadc and cada cadmium resistance genes of a number of microorganisms. transfer and expression of the b. stearothermophilus lv cada or cadc/ cada genes in e. coli caused increased cadmium chloride susceptibility in the bacterial host. transfer of cadc alone did not r ... | 2002 | 12177740 |
| aerobic metabolism of phenylacetic acids in azoarcus evansii. | the aerobic metabolism of phenylacetic acid (pa) and 4-hydroxyphenylacetic acid (4-ohpa) was investigated in the beta-proteobacterium azoarcus evansii. evidence for the existence of two independent catabolic pathways for pa and 4-ohpa is presented. 4-ohpa metabolism involves the formation of 2,5-dihydroxyphenylacetate (homogentisate) and maleylacetoacetate catalyzed by specifically induced 4-ohpa 1-monooxygenase and homogentisate 1,2-dioxygenase. the metabolism of pa starts by its activation to ... | 2002 | 12189419 |
| site-directed mutagenesis of tyr354 in geobacillus stearothermophilus alanine racemase identifies a role in controlling substrate specificity and a possible role in the evolution of antibiotic resistance. | | 2002 | 12203980 |
| purification and characterization of dna helicase bsth2 from bacillus stearothermophilus. | in the purification of dna helicase bsth1 we have partially purified the second dna helicase bsth2 from bacillus stearothermophilus through polymin p precipitation, ammonia sulfate precipitation and chromatographic steps with deae-cellulose, phosphocellulose, blue-sepharose, fplc superose 12, mono q and second mono q. the atpase activity of bsth2 depends on mg(2+) and is differentially stimulated by different types of nucleic acids. bsth2 has a maximal atpase activity at 55 degrees. the atpase a ... | 1997 | 12215800 |
| purification and characterization of dna helicase bsth1 from bacillus stearothermophilus. | we have partially purified a dna helicase bsth1 from bacillus stearothermophilus through polymin p precipitation, ammonia sulfate precipitation and column chromatographic steps with pheny1-sepharose, deae-cellulose, phosphocellulose, fplc mono q and superose 12. bsth1 possesses a dna-dependent atpase activity in the presence of mg(2+). the atpase activity of bsth1 is differentially stimulated by the presence of different types of nucleic acids. bsth1 has an optimal atpase activity at 55 degrees. ... | 1996 | 12232591 |
| prfa protein of bacillus species: prediction and demonstration of endonuclease activity on dna. | the prfa gene product of gram-positive bacteria is unusual in being implicated in several cellular processes; cell wall synthesis, chromosome segregation, and dna recombination and repair. however, no homology of prfa with other proteins has been evident. here we report a structural relationship between prfa and the restriction enzyme pvuii, and thereby produce models that predict that prfa binds dna. indeed, wild-type bacillus stearothermophilus prfa, but not a catalytic site mutant, nicked one ... | 2002 | 12237459 |
| the purification and characterization of a bacillus stearothermophilus methionine aminopeptidase (metap). | methionine aminopeptidase (metap) catalyzes the removal of an amino-terminal methionine from a newly synthesized polypeptide. the enzyme was purified to homogeneity from bacillus stearothermophilus (kctc 1752) by a procedure that involves heat precipitation and four sequential chromatographs (including deaesepharose ion exchange, hydroxylapatite, ultrogel aca 54 gel filtration, and reactive red 120 dye affinity chromatography). the apparent molecular masses of the enzyme were 81,300 da and 41,00 ... | 2002 | 12297034 |
| different unfolding pathways for mesophilic and thermophilic homologues of serine hydroxymethyltransferase. | to determine how much information can be transferred from folding and unfolding studies of one protein to another member of the same family or between the mesophilic and thermophilic homologues of a protein, we have characterized the equilibrium unfolding process of the dimeric enzyme serine hydroxymethyltransferase (shmt) from two sources, bacillus subtilis (bsshmt) and bacillus stearothermophilus (bstshmt). although the sequences of the two enzymes are highly identical ( approximately 77%) and ... | 2002 | 12356312 |
| angiotensin i-converting enzyme inhibitory peptides derived from wakame (undaria pinnatifida) and their antihypertensive effect in spontaneously hypertensive rats. | seven kinds of angiotensin i-converting enzyme (ace) inhibitory peptides were isolated from the hydrolysates of wakame (undaria pinnatifida) by protease s "amano" (from bacillus stearothermophilus) by using three-step high-performance liquid chromatography (hplc) on a reverse-phase column. these peptides were identified by amino acid composition analysis, sequence analysis, and liquid chromatography-mass spectrometry (lc-ms), as val-tyr (ic(50) = 35.2 microm), ile-tyr (6.1 microm), ala-trp (18.8 ... | 2002 | 12358510 |
| inhibition of adhesion of enterotoxigenic escherichia coli k88 by soya bean tempe. | tempe is a traditional fungal fermented food made from soaked and cooked soya beans. it has been associated with antidiarrhoeal characteristics. this study investigated potential inhibitory effects of tempe on enterotoxigenic escherichia coli (etec) k88. | 2002 | 12358694 |
| proteomic analysis of a thermostable superoxide dismutase from bacillus stearothermophilus tls33. | thermophilic bacterium bacillus stearothermophilus tls33 isolated from a hot spring in chiang mai, thailand produces an extracellular superoxide dismutase (sod). sod is a free radical metabolizing enzyme that protects the cell membrane from damage by the highly reactive superoxide free radicals. to identify the secreted sod, we used the systematically proteomic approaches of two-dimensional polyacrylamide gel electrophoresis (2-d page) analysis and database searching. the bacterium was grown in ... | 2002 | 12362349 |
| mapping and sequencing of cardiolipins from geobacillus stearothermophilus nrs 2004/3a by positive and negative ion nanoesi-qtof-ms and ms/ms. | in the course of systematic studies on surface layer (s-layer) glycoproteins of bacilli, the chloroform/methanol extract from whole cells of geobacillus stearothermophilus nrs 2004/3a has been submitted to ms analysis. glucosylated cardiolipins were found as minor components of the total lipid and phospholipid mixture by de novo identification. after purification of the crude extract using a combined column chromatography/2d tlc protocol, structural investigations of components in the lipid frac ... | 2002 | 12375283 |
| genes coding for a new pathway of aerobic benzoate metabolism in azoarcus evansii. | a new pathway for aerobic benzoate oxidation has been postulated for azoarcus evansii and for a bacillus stearothermophilus-like strain. benzoate is first transformed into benzoyl coenzyme a (benzoyl-coa), which subsequently is oxidized to 3-hydroxyadipyl-coa and then to 3-ketoadipyl-coa; all intermediates are coa thioesters. the genes coding for this benzoate-induced pathway were investigated in the beta-proteobacterium a. evansii. they were identified on the basis of n-terminal amino acid sequ ... | 2002 | 12399500 |
| characterization of trehalose phosphorylase from bacillus stearothermophilus sk-1 and nucleotide sequence of the corresponding gene. | a bacterial trehalose phosphorylase (tpase; ec 2.4.1.64) was purified from the culture supernatant of bacillus stearothermophilus sk-1 to apparent homogeneity, and some properties were investigated. furthermore, a gene from sk-1 responsible for the tpase was cloned by southern hybridization with a degenerate oligonucleotide probe synthesized on the basis of the n-terminal sequence of the purified enzyme. the mr of the enzyme was estimated to be 150,000 by gel filtration and 83,000 by sds-page, s ... | 2002 | 12400680 |
| influence of induced fit in the interaction of bacillus subtilis trp rna-binding attenuator protein and its rna antiterminator target oligomer. | in the presence of excess tryptophan, tryptophan-activated trap (trp rna-binding attenuator protein) binds to a specific target in the trp-leader transcript, which induces the formation of a transcription terminator and transcription halts in the leader region. in the absence of tryptophan, trap does not bind rna, an antiterminator forms, and the operon is expressed. although the ternary complex involving trap (bacillus stearothermophilus), tryptophan, and the rna target has recently been crysta ... | 2002 | 12402353 |
| evolution of signalling in the sporulation phosphorelay. | two-component and phosphorelay signal transduction systems are believed to function as environ-mental sensors that programme gene expression to the composition of the ecological niche in which a microbe normally resides. the question of how evolutionarily related bacteria that occupy different environments change their signal transduction pathways to adapt to such environments was asked of the sporulation phosphorelay of bacillus subtilis, bacillus halodurans, bacillus anthracis and bacillus ste ... | 2002 | 12406209 |
| crystal structure of a thermostable lipase from bacillus stearothermophilus p1. | we describe the first lipase structure from a thermophilic organism. it shares less than 20% amino acid sequence identity with other lipases for which there are crystal structures, and shows significant insertions compared with the typical alpha/beta hydrolase canonical fold. the structure contains a zinc-binding site which is unique among all lipases with known structures, and which may play a role in enhancing thermal stability. zinc binding is mediated by two histidine and two aspartic acid r ... | 2002 | 12417199 |
| the 2b domain of the escherichia coli rep protein is not required for dna helicase activity. | the escherichia coli rep protein is a 3' to 5' sf1 dna helicase required for replication of bacteriophage phix174 in e. coli, and is structurally homologous to the e. coli uvrd helicase and the bacillus stearothermophilus pcra helicase. previous crystallographic studies of rep protein bound to single-stranded dna revealed that it can undergo a large conformational change consisting of an approximately 130 degrees rotation of its 2b subdomain about a hinge region connected to the 2a subdomain. ba ... | 2002 | 12441398 |
| stable ammonia-specific nad synthetase from bacillus stearothermophilus: purification, characterization, gene cloning, and applications. | bacillus stearothermophilus h-804 isolated from a hot spring in beppu, japan, produced an ammonia-specific nad synthetase (ec 6.3.1.5). the enzyme specifically used nh3 as an amide donor for the synthesis of nad as it formed amp and pyrophosphate from deamide-nad and atp. none of the l-amino acids tested, such as l-asparagine or l-glutamine, or other amino compounds such as urea, uric acid, or creatinine was used instead of nh3. mg2+ was needed for the activity, and the maximum enzyme activity w ... | 2002 | 12450114 |
| growth-promoting effect of carbon material upon bacterial cells propagating through a distance. | carbon material such as graphite and activated charcoal, but not diamond, causes the promotion of growth of certain bacteria under ordinarily non-permissive stress conditions over a distance of several centimeters. bacillus carboniphilus under the stress of a high kcl concentration and high temperature responded to this remote effect of carbon material with enhanced growth, and thermophile bacterium bacillus stearothermophilus responded similarly yet moderately under the stress of low temperatur ... | 1997 | 12501323 |
| lysyl-trna synthetase from bacillus stearothermophilus: the trp314 residue is shielded in a non-polar environment and is responsible for the fluorescence changes observed in the amino acid activation reaction. | three trp variants of lysyl-trna synthetase from bacillus stearothermophilus, in which either one or both of the two trp residues within the enzyme (trp314 and trp332) were substituted by a phe residue, were produced by site-directed mutagenesis without appreciable loss of catalytic activity. the following two phenomena were observed with w332f and with the wild-type enzyme, but not with w314f: (1) the addition of l-lysine alone decreased the protein fluorescence of the enzyme, but the addition ... | 2003 | 12507472 |
| expression, purification, and crystallization of glutamyl-trna(gln) specific amidotransferase from bacillus stearothermophilus. | although the genes that encode the glutamyl-trna(gln) (glu-trna(gln)) specific amidotransferase (glu-adtase) from various bacteria and eukaryotic organelles are known, the precise mechanism of the enzyme is still unclear. one of the reasons is that there is no information on the three-dimensional structure of the complex, the glu-adtase:glu-trna(gln):atp:amino group donor. to obtain the crystals of glu-adtase, the glu-adtase of bacillus stearothermophilus was overexpressed and purified after clo ... | 2002 | 12521300 |
| crystal structures of the bacillus stearothermophilus cca-adding enzyme and its complexes with atp or ctp. | cca-adding enzymes polymerize cca onto the 3' terminus of immature trnas without using a nucleic acid template. the 3.0 a resolution crystal structures of the cca-adding enzyme from bacillus stearothermophilus and its complexes with atp or ctp reveal a seahorse-shaped subunit consisting of four domains: head, neck, body, and tail. the head is structurally homologous to the palm domain of dna polymerase beta but has additional structural features and functions. the neck, body, and tail represent ... | 2002 | 12526808 |
| three-dimensional structure and substrate binding of bacillus stearothermophilus neopullulanase. | crystal structures of bacillus stearothermophilus trs40 neopullulanase and its complexes with panose, maltotetraose and isopanose were determined at resolutions of 1.9, 2.4, 2.8 and 3.2a, respectively. since the latter two carbohydrates are substrates of this enzyme, a deactivated mutant at the catalytic residue glu357-->gln was used for complex crystallization. the structures were refined at accuracies with r.m.s. deviations of bond lengths and bond angles ranging from 0.005a to 0.008a and 1.3 ... | 2003 | 12547200 |
| [production and some properties of a thermophilic protease from bacillus stearothermophilus wf146]. | the factors affecting bacillus stearothermophilus wf146 for thermophilic protease producing have been investigated, more than 600 units of enzyme in 1 ml of fermented culture could be achieved under suitable condition. the protease had a molecular weight around 34 kd estimated by sds-page, and functioned optimally at ph 8.0 and 80 degrees c, respectively. in addition, the enzyme exhibited high temperature tolerance and was stable at a wide range of ph, and ca2+ played a key role for the stabilit ... | 2000 | 12548943 |
| [synthesis of galacto-oligosaccharides by immobilized bacillus stearothermophilus]. | bacillus stearothermophilus was embedded in sodium alginate, chitosan, gelatin respectively and utilized for galacto-oligosaccharides (gos) production. by comparing with each other in the enzyme recovery, optimal reaction conditions, yields of gos and mechanical strength of the carriers, the gelatin was selected as better carrier for immobilization. ph, temperature, lactose concentration, lactose conversion and mass transfer resistance of carrier significantly influenced the yield of gos. the ma ... | 2001 | 12549092 |
| crystal structure of two ternary complexes of phosphorylating glyceraldehyde-3-phosphate dehydrogenase from bacillus stearothermophilus with nad and d-glyceraldehyde 3-phosphate. | the crystal structure of the phosphorylating glyceraldehyde-3-phosphate dehydrogenase (gapdh) from bacillus stearothermophilus was solved in complex with its cofactor, nad, and its physiological substrate, d-glyceraldehyde 3-phosphate (d-g3p). to isolate a stable ternary complex, the nucleophilic residue of the active site, cys(149), was substituted with alanine or serine. the c149a and c149s gapdh ternary complexes were obtained by soaking the crystals of the corresponding binary complexes (enz ... | 2003 | 12569100 |
| development of a genetic system for hyperthermophilic archaea: expression of a moderate thermophilic bacterial alcohol dehydrogenase gene in sulfolobus solfataricus. | the escherichia coli/sulfolobus solfataricus shuttle vector pexss was used as a cloning vehicle for the gene transfer and expression of two bacterial genes in sulfolobus solfataricus. the alcohol dehydrogenase (adh) from the moderate thermophilic bacillus stearothermophilus (strain lldr) and a mutagenised version encoding a less thermostable adh enzyme were the selected genes. s. solfataricus adh promoter and aspartate aminotransferase terminator were used to drive the heterologous gene expressi ... | 2003 | 12583906 |
| cloning of the maltose phosphorylase gene from bacillus sp. strain rk-1 and efficient production of the cloned gene and the trehalose phosphorylase gene from bacillus stearothermophilus sk-1 in bacillus subtilis. | the maltose phosphorylase (mpase) gene of bacillus sp. strain rk-1 was cloned by pcr with oligonucleotide primers designed on the basis of a partial n-terminal amino acid sequence of the purified enzyme. the mpase gene consisted of 2,655 bp encoding a theoretical protein with a mr of 88,460, and had no secretion signal sequence, although most of the mpase activity was detected in the culture supernatant of rk-1. this cloned mpase gene and the trehalose phosphorylase (tpase) gene from bacillus st ... | 2002 | 12596853 |
| site-directed mutagenesis of a loop at the active site of e1 (alpha2beta2) of the pyruvate dehydrogenase complex. a possible common sequence motif. | limited proteolysis of the pyruvate decarboxylase (e1, alpha2beta2) component of the pyruvate dehydrogenase (pdh) multienzyme complex of bacillus stearothermophilus has indicated the importance for catalysis of a site (tyr281-arg282) in the e1alpha subunit (chauhan, h.j., domingo, g.j., jung, h.-i. & perham, r.n. (2000) eur. j. biochem. 267, 7158-7169). this site appears to be conserved in the alpha-subunit of heterotetrameric e1s and multiple sequence alignments suggest that there are additiona ... | 2003 | 12603319 |
| induction of specific t-helper and cytolytic responses to epitopes displayed on a virus-like protein scaffold derived from the pyruvate dehydrogenase multienzyme complex. | the icosahedral protein scaffold (1.5mda) generated by self-assembly of the catalytic domains of the dihydrolipoyl acetyltransferase core of the pyruvate dehydrogenase multienzyme complex from bacillus stearothermophilus has been engineered to display 60 copies of one or more peptide epitopes on a single molecule (e2disp). an e2disp scaffold displaying pep23, a 15-residue b- and t-helper epitope from the reverse transcriptase of hiv-1, was able to induce a pep23-specific t-helper response in cel ... | 2003 | 12615447 |
| effect of carrier materials on the resistance of spores of bacillus stearothermophilus to gaseous hydrogen peroxide. | the testing of the h2o2 decontamination process using spores of bacillus stearothermophilus has gained widespread acceptance. usually, commercially available biological indicators (bis) with a specified resistance to h2o2 are challenged to qualify the process. the question arises whether the resistance of test spores is dependant on the type of carrier material and whether the resistance is representative for the system under test. the objective of the study is to quantify the effect of differen ... | 2003 | 12643502 |
| secretory expression in escherichia coli and single-step purification of a heat-stable alkaline protease. | bacteriocin release proteins (brps) can be used for the release of heterologous proteins from the escherichia coli cytoplasm into the culture medium. the gene for a highly thermostable alkaline protease was cloned from bacillus stearothermophilus f1 by the polymerase chain reaction. the recombinant f1 protease was efficiently excreted into the culture medium using e. coli xl1-blue harboring two vectors: ptrchis bearing the protease gene and pjl3 containing the brps. both vectors contain the e. c ... | 2003 | 12651108 |
| high-resolution x-ray structure of the dna-binding protein hu from the hyper-thermophilic thermotoga maritima and the determinants of its thermostability. | the histone-like dna-binding proteins (hu) are a convenient model for studying factors affecting thermostability because of their relatively simple, easily comparable structures, their common function, and their presence in organisms of widely differing thermostability. we report the determination of the high-resolution structure (1.53 a) at 273 k and 100 k of the hu protein from the hyper-thermophilic eubacterium thermotoga maritima(hu tmar, t(m)=80.5 degrees c). the structural data presented c ... | 2003 | 12664263 |
| optimization of a rf-generated cf4/o2 gas plasma sterilization process. | a sterilization process with the use of rf-generated (13.56 mhz) cf(4)/o(2) gas plasma was optimized in regards to power, flow rate, exposure time, and rf-system type. the dependency of the sporicidal effect on the spore inoculum positioning in the chamber of the rf systems was also investigated. dried bacillus stearothermophilus atcc 7953 endospores were used as test organisms. the treatments were evaluated on the basis of survival curves and corresponding d values. the only parameter found to ... | 2003 | 12687716 |
| dual coenzyme specificity of photosynthetic glyceraldehyde-3-phosphate dehydrogenase interpreted by the crystal structure of a4 isoform complexed with nad. | photosynthetic glyceraldehyde-3-phosphate dehydrogenase (gapdh) of spinacia oleracea belongs to a wide group of gapdhs found in most organisms displaying oxygenic photosynthesis, including cyanobacteria, green and red algae, and higher plants. as a major catalytic difference with respect to glycolytic gapdh, photosynthetic gapdh exhibits dual cofactor specificity toward pyridine nucleotides with a preference for nadp(h). here we report the crystal structure of nad-complexed recombinant a(4)-gapd ... | 2003 | 12705826 |
| maltosyl-erythritol, a major transglycosylation product of erythritol by bacillus stearothermophilus maltogenic amylase. | this study was done to modify erythritol to change its physicochemical and sensory properties. erythritol, a four-carbon sugar alcohol, was transglycosylated by bacillus stearothermophilus maltogenic amylase with maltotriose as a donor molecule. the presence of various transglycosylation products of erythritol was confirmed by tlc and high performance ion exchange chromatography (hpic). the major transfer product was purified by gel filtration chromatography on bio-gel p-2. examination by lc-ms, ... | 2003 | 12723599 |
| a side reaction of alanine racemase: transamination of cycloserine. | alanine racemase (ec 5.1.1.1) catalyzes the interconversion of alanine enantiomers, and thus represents the first committed step involved in bacterial cell wall biosynthesis. cycloserine acts as a suicide inhibitor of alanine racemase and as such, serves as an antimicrobial agent. the chemical means by which cycloserine inhibits alanine racemase is unknown. through spectroscopic assays, we show here evidence of a pyridoxal derivative (arising from either isomer of cycloserine) saturated at the c ... | 2003 | 12741835 |
| the phosphotriesterase gene opda in agrobacterium radiobacter p230 is transposable. | we report a transposase gene (tnpa) upstream of the opda phosphotriesterase gene of agrobacterium radiobacter p230, as well as inverted repeats indicative of insertion sequences, flanking the two genes. both the tnpa gene and the inverted repeats resemble the tn610 transposon from mycobacterium fortuitum. two additional putative open reading frames separate opda and tnpa with inferred translation products with similarity to two proteins encoded on the geobacillus stearothermophilus is5376 transp ... | 2003 | 12757939 |
| ahld, an n-acylhomoserine lactonase in arthrobacter sp., and predicted homologues in other bacteria. | quorum sensing is a signalling mechanism that controls diverse biological functions, including virulence, via n-acylhomoserine lactone (ahl) signal molecules in gram-negative bacteria. with the aim of isolating strains or enzymes capable of blocking quorum sensing by inactivating ahl, bacteria were screened for ahl degradation by their ability to utilize n-3-oxohexanoyl-l-homoserine lactone (ohhl) as the sole carbon source. among four isolates, strain ibn110, identified as arthrobacter sp., was ... | 2003 | 12777494 |
| the structure of glyceraldehyde 3-phosphate dehydrogenase from alcaligenes xylosoxidans at 1.7 a resolution. | the enzyme glyceraldehyde-3-phosphate dehydrogenase (gapdh) from the gram-negative denitrifying bacterial species alcaligenes xylosoxidans was purified and crystallized as a contaminant protein during purification of nitrous oxide reductase. this is the first structure of a gapdh from a denitrifying species. the crystal structure was solved at 1.7 a resolution by molecular replacement using the structure of gapdh from bacillus stearothermophilus as a starting model. the quality of the structure ... | 2003 | 12777799 |
| overexpression, purification, and characterization of the recombinant leucine aminopeptidase ii of bacillus stearothermophilus. | for expression of bacillus stearothermophilus ncib 8924 leucine aminopeptidase ii (lap ii) in escherichia coli regulated by a t5 promoter, the gene was amplified by polymerase chain reaction and cloned into expression vector pqe-32 to generate pqe-lapii. the his(6)-tagged enzyme was overexpressed in iptg-induced e. coli m15 (pqe-lapii) as a soluble protein and was purified to homogeneity by nickel-chelate chromatography to a specific activity of 425 u/mg protein with a final yield of 76%. the su ... | 2003 | 12783191 |
| reaction mechanism of the heterotetrameric (alpha2beta2) e1 component of 2-oxo acid dehydrogenase multienzyme complexes. | pyruvate decarboxylase (e1) catalyzes the first two reactions of the four involved in oxidative decarboxylation of pyruvate by the pyruvate dehydrogenase (pdh) multienzyme complex. it requires thiamin diphosphate to bring about the decarboxylation of pyruvate, which is followed by the reductive acetylation of a lipoyl group covalently bound to the n(6) amino group of a lysine residue in the second catalytic component, a dihydrolipoyl acetyltransferase (e2). replacement of two histidine residues ... | 2003 | 12795594 |
| detailed kinetic analysis and identification of the nucleophile in alpha-l-arabinofuranosidase from geobacillus stearothermophilus t-6, a family 51 glycoside hydrolase. | alpha-l-arabinofuranosidases cleave the l-arabinofuranoside side chains of different hemicelluloses and are key enzymes in the complete degradation of the plant cell wall. the alpha-l-arabinofuranosidase from geobacillus stearothermophilus t-6, a family 51 glycoside hydrolase, was subjected to a detailed mechanistic study. aryl-alpha-l-arabinofuranosides with various leaving groups were synthesized and used to verify the catalytic mechanism and catalytic residues of the enzyme. the steady-state ... | 2002 | 12221104 |
| site-directed mutagenesis reveals roles for conserved amino acid residues in the hexameric dna helicase dnab from bacillus stearothermophilus. | site-directed mutagenesis studies on conserved amino acid residues within motifs h1, h1a, h2 and h3 of the hexameric replicative helicase dnab from bacillus stearothermophilus revealed specific functions associated with these residues. in particular, residues that coordinate a bound mg2+ in the active site (t217 and d320) are important for the function of the enzyme but are not required for the formation of stable hexamers. a conserved glutamic acid (e241) in motif h1a is likely to be involved i ... | 2002 | 12235389 |