Publications

visualizing dna replication in a catalytically active bacillus dna polymerase crystal.	dna polymerases copy dna templates with remarkably high fidelity, checking for correct base-pair formation both at nucleotide insertion and at subsequent dna extension steps. despite extensive biochemical, genetic and structural studies, the mechanism by which nucleotides are correctly incorporated is not known. here we present high-resolution crystal structures of a thermostable bacterial (bacillus stearothermophilus) dna polymerase i large fragments with dna primer templates bound productively ...	1998	9440698
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
genomic analysis of the genes encoding ribosomal proteins in eight eubacterial species and saccharomyces cerevisiae.	the complete genomic nucleotide sequence data of more than 10 unicellular organisms have become available. during the past years, we have been focusing our attention to the analysis of the structure and function of the ribosome and its protein components. by making use of the genomic sequence data, our work can now be extended to comparative analysis of the ribosomal components at the genomic level. such analysis will contribute to our understanding of the structure-function relationship of the ...	1998	11072316
bacillus stearothermophilus for thermophilic production of l-lactic acid.	a process for the continuous production of high purity l-lactic acid in a membrane bioreactor at 65 degrees c has been developed. two different bacillus stearothermophilus strains have been tested in batch experiments. lactic acid yields are between 60 and more than 95% of theoretical yields. the amounts of ethanol, acetate, and formate formed varied between 0 and 0.4, 0 and 0.1, and 0 and 0.5, respectively (mol/mol glucose). all byproducts are valuable and may be separated easily by rectificati ...	1998	18576053
cytotoxicity and membrane interaction of tamoxifen as affected by ca(2+) and mg(2+): use of a bacterial model system.	a strain of bacillus stearothermophilus was used as a model to study the interaction of tamoxifen (tam) with the membrane and the cytostatic antiproliferative effects not related to estrogen binding. tam inhibits the growth of b. stearothermophilus as a function of concentration. the supplementation of the growth medium with ca(2+) or mg(2+) partially relieves the growth inhibition by tam, allowing growth at tam concentrations that fully impair growth in the basal medium. fluorescence polarizati ...	1999	20654520
direct correlationship between proton translocation and growth yield: an analysis of the respiratory chain of bacillus stearothermophilus.	thermophilic bacilli contain cytochrome caa3-type cytochrome c oxidase as the main terminal oxidase in the respiratory chain. a mutant strain, named k-17, lacking cytochrome caa3 and exhibiting very low n,n,n',n'-tetramethyl-p-phenylene diamine oxidase activity, was isolated by random mutation from bacillus stearothermophilus k1041 (sakamoto, j. et al., fems microbiol. lett., 143, 151-158, 1996). comparing this mutant with the parent strain k1041, we observed the following differences in energy- ...	1999	16232504
enzymatic synthesis of fructose 1,6-diphosphate with atp regeneration in a batch reactor and a semibatch reactor using purified enzymes of bacillus stearothermophilus.	the enzymatic synthesis of fructose 1,6-diphosphate (fdp), an important glycolytic intermediate whose applications in the field of medicine have generated a great deal of interest, was performed in a batch reactor and a semibatch reactor. using the batch reactor, fdp was first synthesized from glucose by three enzymatic reactions and the atp consumed was regenerated simultaneously using conjugated enzymes, all of which were purified from crude cell extract of thermophilic bacillus stearothermoph ...	1999	16232527
enzymatic production of fructose 1,6-diphosphate using crude cell extract of bacillus stearothermophilus.	the enzymatic production of fructose 1,6-diphosphate (fdp) from glucose was performed in a batch reactor and a semibatch reactor using the crude cell extract of bacillus stearothermophilus which contains all four enzymes required for the synthesis. the experimental results of the yield and the time courses of fdp production obtained using various enzyme concentrations were in good agreement with the theoretical predictions calculated based on the differential equations including the rate equatio ...	1999	16232540
a new sterility test for cow's milk using alanine racemase gene as the index.	oligonucleotide primers designed from consensus sequences of alanine racemase genes were used for a sterility test of cow's milk by polymerase chain reaction (pcr). commercial cow's milk in two 250 ml packages was separately centrifuged at 5000 x g for 10 min, bacterial cells in each precipitate were cultivated at 30 and 55 degrees c for 5 h in luria-bertani medium, and the cells from each culture were mixed and used for the pcr after being treated with 0.1 n naoh at 60 degrees c for 10 min. whe ...	1999	16232568
experimental investigation of fructose 1,6-diphosphate production and simultaneous atp regeneration by conjugated enzymes in an ultrafiltration hollow-fiber reactor.	the enzymatic synthesis of fructose 1,6-diphosphate (fdp) from glucose and the enzymatic atp regeneration were performed simultaneously in an ultrafiltration hollow-fiber reactor using both the purified enzymes and the crude cell extract of bacillus stearothermophilus. the process consisted of the three-step synthetic reactions catalyzed by glucokinase, phosphoglucose isomerase and phosphofructokinase, and the atp regeneration reaction catalyzed by acetate kinase. the experimental results of the ...	1999	16232677
catabolite repression of the xylanase gene (xyna) expression in bacillus stearothermophilus no. 236 and b. subtilis.	catabolite repression of the bacillus stearothermophilus no. 236 xyna gene, encoding an extracellular xylanase, was investigated in this work. expression of the xyna gene in the b. stearothermophilus strain was found to be subject to glucose catabolite repression, and the level of repression was about 50-fold when the relative amounts of xyna transcript synthesized on different carbon sources were analyzed. the experiments with the b. subtilis mw15 strains carrying plasmids containing the xyna:: ...	1999	10664837
arginine-55 in the beta-arm is essential for the activity of dna-binding protein hu from bacillus stearothermophilus.	dna-binding protein hu (bsthu) from bacillus stearothermophilus is a homodimeric protein which binds to dna in a sequence-nonspecific manner. in order to identify the arg residues essential for dna binding, four arg residues (arg-53, arg-55, arg-58, and arg-61) within the beta-arm structure were replaced either by gln, lys, or glu residues, and the resulting mutants were characterized with respect to their dna-binding activity by a filter-binding analysis and surface plasmon resonance analysis. ...	1999	10664859
release of bacteria during the purge cycles of steam-jacketed sterilizers.	the design of the steam-jacketed sterilizer includes an exterior air-gap fixture through which purged chamber aerosols potentially could escape into the ambient environment. studies of the purge cycle in two sterilizer models tested the potential release of a genetically marked enterococcus faecalis, together with bacillus stearothermophilus spores introduced as exposed cultures. direct plate counts, broth enrichment and polymerase chain reaction analysis were used to confirm any released organi ...	1999	10795367
glucose catabolism of escherichia coli strains with increased activity and altered regulation of key glycolytic enzymes.	this study investigates the effect of overexpression of key glycolytic enzymes exhibiting either native or alternative allosteric regulation on glucose bioconversion by resting escherichia coli cells previously engineered for ethanol production. homologous and heterologous pyruvate kinases (pyk) and phosphofructokinases (pfk) were individually and simultaneously overexpressed. overexpression of the e. coli pfk led to a shift from ethanol to lactate formation (three-fold above the control level) ...	1999	10935925
density functional and electrostatic calculations of manganese superoxide dismutase active site complexes in protein environments.	density functional and electrostatic methods have been applied to calculate active site geometries and the redox potential of manganese superoxide dismutase (mnsod). the initial active site clusters were built up by including only first-shell side chain ligands and then augmented by second-shell ligands. the density functional optimized mn-ligand bond lengths for the reduced complexes in general compared fairly well with protein crystallography data; however, large deviations for calculated mn-o ...	1999	11670865
morpho-structural variations of bacterial spores after treatment in steam vacuum assisted autoclave.	this study intended to verify, through microbiological techniques and tem investigations, the killing of bacterial spores after treatment in steam autoclave, and to propose strictly morphological considerations about the target of this sterilisation process. autoclave is the most common device for sterilising instruments in order to prevent cross infections in dental offices. the autoclave efficiency has been improved in the last years and part of this improvement is related to both a better and ...	1999	11799742
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
gene structure and quinol oxidase activity of a cytochrome bd-type oxidase from bacillus stearothermophilus.	gram-positive thermophilic bacillus species contain cytochrome caa3-type cytochrome c oxidase as their main terminal oxidase in the respiratory chain. we previously identified and purified an alternative oxidase, cytochrome bd-type quinol oxidase, from a mutant of bacillus stearothermophilus defective in the caa3-type oxidase activity (j. sakamoto et al., fems microbiol. lett. 143 (1996) 151-158). compared with proteobacterial counterparts, b. stearothermophilus cytochrome bd showed lower molecu ...	1999	10216161
organization of genes for tetrapyrrole biosynthesis in gram--positive bacteria.	clusters of genes encoding enzymes for tetrapyrrole biosynthesis were cloned from bacillus sphaericus, bacillus stearothermophilus, brevibacillus brevis and paenibacillus macerans. the sequences of all hemx genes found, and of a 6.3 kbp hem gene cluster from p. macerans, were determined. the structure of the hem gene clusters was compared to that of other gram-positive bacteria. the bacillus and brevibacillus species have a conserved organization of the genes hemaxcdbl, required for biosynthesis ...	1999	10217486
the mycelium-associated streptomyces reticuli catalase-peroxidase, its gene and regulation by furs.	during early stages of growth, streptomyces reticuli synthesizes a hyphae-associated, haem-containing enzyme which exhibits catalase and peroxidase activities with broad substrate specificity (cpeb). the purified dimeric enzyme (160 kda) consists of two identical subunits. using anti-cpeb antibodies and an expression- as well as a mini-library, the corresponding cpeb gene was identified and sequenced. it encodes a protein of 740 aa with a molecular mass of 81.3 kda. the deduced protein shares th ...	1999	10217488
folding of the multidomain ribosomal protein l9: the two domains fold independently with remarkably different rates.	the folding and unfolding behavior of the multidomain ribosomal protein l9 from bacillus stearothermophilus was studied by a novel combination of stopped-flow fluorescence and nuclear magnetic resonance (nmr) spectroscopy. one-dimensional 1h spectra acquired at various temperatures show that the c-terminal domain unfolds at a lower temperature than the n-terminal domain (tm = 67 degrees c for the c-terminal domain, 80 degrees c for the n-terminal domain). nmr line-shape analysis was used to dete ...	1999	10220353
the crystal structure of a multifunctional protein: phosphoglucose isomerase/autocrine motility factor/neuroleukin.	phosphoglucose isomerase (pgi) plays a central role in both the glycolysis and the gluconeogenesis pathways. we present here the complete crystal structure of pgi from bacillus stearothermophilus at 2.3-a resolution. we show that pgi has cell-motility-stimulating activity on mouse colon cancer cells similar to that of endogenous autocrine motility factor (amf). pgi can also enhance neurite outgrowth on neuronal progenitor cells similar to that observed for neuroleukin. the results confirm that p ...	1999	10318897
structure of the arginine repressor from bacillus stearothermophilus.	the arginine repressor (argr) is a hexameric dna-binding protein that plays a multifunctional role in the bacterial cell. here, we present the 2.5 a structure of apo-argr from bacillus stearothermophilus and the 2.2 a structure of the hexameric argr oligomerization domain with bound arginine. this first view of intact argr reveals an approximately 32-symmetric hexamer of identical subunits, with six dna-binding domains surrounding a central oligomeric core. the difference in quaternary organizat ...	1999	10331868
structural and functional studies on the overproduced l11 protein from thermus thermophilus.	the l11 ribosomal protein from thermus thermophilus (tthl11) has been overproduced and purified to homogeneity using a two-step purification protocol. the overproduced protein carries a similar methylation pattern at lys-3 as does its homolog from escherichia coli. chymotrypsin digested only a small part of the tthl11 protein and did not cleave tthl11 into two peptides, as in the case of ecol11, but produced only a single n-terminal peptide. tryptic digestion of tthl11 also produced an n-termina ...	1999	10333296
purification and characterization of alkaline phosphatase from bacillus stearothermophilus.	soluble alkaline phosphatase from the thermophilic bacterium bacillus stearothermophilus was purified by a combination of chromatographic methods, and its properties were examined. the purified enzyme had specific activity of 4.43 micromol p-nitrophenol/min per mg of protein and seemed to be a single band on sds/page with a molecular mass of 32 kda. its apparent km for p-nitrophenyl phosphate was 1.114 mm. the enzyme exhibited an optimal ph of approx. 9.0 and exhibited its highest activity at 60 ...	1999	10334954
thermal resistance of bacterial spores in milk-based beverages supplemented with nisin.	the effect of nisin, added in the form of nisaplin, on the thermal resistance of bacterial spores and the effects of medium composition, exposure time, and ph on nisin enhancement of heat sensitivity were evaluated. nisin apparently required specific nutrients to sensitize spores to heat. for example, d130 degrees c values of approximately 10 s were observed in sodium phosphate buffer with and without 6% sucrose with no significant (p> or =0.05) differences detected as a result of increased nisi ...	1999	10340669
role of tyrosine 265 of alanine racemase from bacillus stearothermophilus.	tyrosine 265 (y265) of bacillus stearothermophilus is believed to serve as a catalytic base specific to the l-enantiomer of a substrate amino acid by removing (or returning) an alpha-hydrogen from (or to) the isomer on the basis of the x-ray structure of the enzyme [stamper, c.g., morollo, a.a., and ringe, d. (1998) biochemistry 37, 10438-10443]. we found that the y265-->ala mutant (y265a) enzyme is virtually inactive as a catalyst for alanine racemization. we examined the role of y265 further w ...	1999	10348897
risk analysis of the thermal sterilization process. analysis of factors affecting the thermal resistance of microorganisms.	a risk analysis was applied to experimental heat resistance data. this analysis is an approach for processing experimental thermobacteriological data in order to study the variability of d and z values of target microorganisms depending on the deviations range of environmental factors, to determine the critical factors and to specify their critical tolerance. this analysis is based on sets of sensitivity functions applied to a specific case of experimental data related to the thermoresistance of ...	1999	10357273
the glucuronic acid utilization gene cluster from bacillus stearothermophilus t-6.	a lambda-embl3 genomic library of bacillus stearothermophilus t-6 was screened for hemicellulolytic activities, and five independent clones exhibiting beta-xylosidase activity were isolated. the clones overlap each other and together represent a 23.5-kb chromosomal segment. the segment contains a cluster of xylan utilization genes, which are organized in at least three transcriptional units. these include the gene for the extracellular xylanase, xylanase t-6; part of an operon coding for an intr ...	1999	10368143
structure of the adenylation domain of an nad+-dependent dna ligase.	dna ligases catalyse phosphodiester bond formation between adjacent bases in nicked dna, thereby sealing the nick. a key step in the catalytic mechanism is the formation of an adenylated dna intermediate. the adenyl group is derived from either atp (in eucaryotes and archaea) or nad+4 (in bacteria). this difference in cofactor specificity suggests that dna ligase may be a useful antibiotic target.	1999	10368271
regulatory features of the trp operon and the crystal structure of the trp rna-binding attenuation protein from bacillus stearothermophilus.	characterization of both the cis and trans -acting regulatory elements indicates that the bacillus stearothermophilustrp operon is regulated by an attenuation mechanism similar to that which controls the trp operon in bacillus subtilis. secondary structure predictions indicate that the leader region of the trp mrna is capable of folding into terminator and anti- terminator rna structures. b. stearothermophilus also encodes an rna-binding protein with 77% sequence identity with the rna-binding pr ...	1999	10369778
bsesi, a restriction endonuclease from bacillus stearothermophilus jo 10-553, which recognizes the novel hexanucleotide sequence 5'-g(g/t)gc(a/c)c-3'.	a new restriction endonuclease bse si has been isolated from bacillus stearothermophilus jo10-553. bse si recognizes a degenerate hexanucleotide sequence 5'-g(g/t)gc(a/c)c-3' and cleaves dna to produce 3[prime]-protruding tetranucleotide ends.	1999	10373580
[homologous locus of genomes of bacillus subtilis and bacillus stearothermophilus, containing levansucrase and levanase genes].		1999	10377564
lys13 plays a crucial role in the functional adaptation of the thermophilic triose-phosphate isomerase from bacillus stearothermophilus to high temperatures.	the thermophilic triose-phosphate isomerases (tims) of bacillus stearothermophilus (btim) and thermotoga maritima (ttim) have been found to possess a his12-lys13 pair instead of the asn12-gly13 pair normally present in mesophilic tims. his12 in btim was proposed to prevent deamidation at high temperature, while the precise role of lys13 is unknown. to investigate the role of the his12 and lys13 pair in the enzyme's thermoadaptation, we reintroduced the "mesophilic residues" asn and gly into both ...	1999	10383424
disordered c-terminal domain of tyrosyl-trna synthetase: secondary structure prediction.	the c-terminal domain (residues 320-419) of tyrosyl-trna synthetase (tyrrs) from bacillus stearothermophilus is disordered in the crystal structure and involved in the binding of the anticodon arm of trna(tyr). the sequences of 11 tyrrss of prokaryotic or mitochondrial origins were aligned and the alignment showed the existence of conserved residues in the sequences of the c-terminal domains. a consensus could be deduced from the application of five programs of secondary structure prediction to ...	1999	10385005
the amino acidic substitution of cysteine 167 by serine (c167s) in bstvi restriction endonuclease of bacillus stearothermophilus v affects its conformation and thermostability.	the restriction endonuclease bstvi from bacillus stearothermophilus v contains three cysteine residues at positions 134, 167 and 180. titration of cys residues with dtnb showed that none of them are involved in disulphide bond formation. cysteine triplets 134 and 167 were modified by recombinant pcr to introduce a serine residue in each case. the mutated genes were cloned into pgem-t vector and transformed into e. coli jm109. even though pgem-t is not designed for expression, the mutant proteins ...	1999	10385008
mildly oxidized gapdh: the coupling of the dehydrogenase and acyl phosphatase activities.	the hydrogen peroxide-induced 'non-phosphorylating' activity of d-glyceraldehyde 3-phosphate dehydrogenase (gapdh) is shown to be a result of the successive action of two forms of the enzyme subunits: one catalyzing production of 1,3-bisphosphoglycerate, and the other performing its hydrolytic decomposition. the latter form is produced by mild oxidation of gapdh in the presence of a low hydrogen peroxide concentration when essential cys-149 is oxidized to the sulfenate derivative. the results ob ...	1999	10386594
alcoholysis reactions from starch with alpha-amylases.	the ability of alpha-amylases from different sources to carry out reactions of alcoholysis was studied using methanol as substrate. it was found that while the enzymes from aspergillus niger and aspergillus oryzae, two well-studied saccharifying amylases, are capable of alcoholysis reactions, the classical bacterial liquefying alpha-amylases from bacillus licheniformis and bacillus stearothermophilus are not. the effect of starch and methanol concentration, temperature and ph on the synthesis of ...	1999	10386619
selective association of protein molecules followed by mass spectrometry.	nanoflow electrospray mass spectrometry was used to monitor the formation of protein heterodimers of hu proteins from bacillus stearothermophilus and bacillus subtilis. this has enabled us to analyze both thermodynamic and kinetic features associated with the dissociation of homodimeric hu proteins. the results obtained correlate well with the kinetics of the protein dissociation process and the free energy difference between homo- and heterodimeric species anticipated from other studies. we sug ...	1999	10386888
probing the unfolding region in a thermolysin-like protease by site-specific immobilization.	protein stabilization by immobilization has been proposed to be most effective if the protein is attached to the carrier at that region where unfolding is initiated. to probe this hypothesis, we have studied the effects of site-specific immobilization on the thermal stability of mutants of the thermolysin-like protease from bacillus stearothermophilus (tlp-ste). this enzyme was chosen because previous studies had revealed which parts of the molecule are likely to be involved in the early steps o ...	1999	10387069
x-ray structure of novamyl, the five-domain "maltogenic" alpha-amylase from bacillus stearothermophilus: maltose and acarbose complexes at 1.7a resolution.	the three-dimensional structure of the bacillus stearothermophilus "maltogenic" alpha-amylase, novamyl, has been determined by x-ray crystallography at a resolution of 1.7 a. unlike conventional alpha-amylases from glycoside hydrolase family 13, novamyl exhibits the five-domain structure more usually associated with cyclodextrin glycosyltransferase. complexes of the enzyme with both maltose and the inhibitor acarbose have been characterized. in the maltose complex, two molecules of maltose are f ...	1999	10387084
structural studies on a 2,3-diphosphoglycerate independent phosphoglycerate mutase from bacillus stearothermophilus.	phosphoglycerate mutase (pgm), an important enzyme in the glycolytic pathway, catalyzes the transfer of a phosphate group between the 2 and the 3 positions of glyceric acid. the gene coding for the 2, 3-diphosphoglycerate independent monomeric pgm from bacillus stearothermophilus (57 kda), whose activity is extremely ph sensitive and has an absolute and specific requirement for mn2+, has been cloned and the enzyme overexpressed and purified to homogeneity. circular dichroism studies showed at mo ...	1999	10388626
introducing transglycosylation activity in a liquefying alpha-amylase.	by mutating ala-289 by phe or tyr in the bacillus stearothermophilus alpha-amylase, we induced this enzyme to perform alcoholytic reactions, a function not present in the wild-type enzyme. this residue was selected from homology analysis with neopullulanase, where the residue has been implicated in the control of transglycosylation [kuriki et al. (1996) j. biol. chem. 271, 17321-173291. we made some inferences about the importance of electrostatic and geometrical modifications in the active site ...	1999	10403384
crystal structure of the atpase domain of translation initiation factor 4a from saccharomyces cerevisiae--the prototype of the dead box protein family.	translation initiation factor 4a (elf4a) is the prototype of the dead-box family of proteins. dead-box proteins are involved in a variety of cellular processes including splicing, ribosome biogenesis and rna degradation. energy from atp hydrolysis is used to perform rna unwinding during initiation of mrna translation. the presence of elf4a is required for the 43s preinitiation complex to bind to and scan the mrna.	1999	10404596
nucleotide sequence, heterologous expression and novel purification of dna ligase from bacillus stearothermophilus(1).	the gene for dna ligase (ec 6.5.1.2) from thermophilic bacterium bacillus stearothermophilus nca1503 has been cloned and the complete nucleotide sequence determined. the ligase gene encodes a protein 670 amino acids in length. the gene was overexpressed in escherichia coli and the enzyme has been purified to homogeneity. preliminary characterisation confirms that it is a thermostable, nad(+)-dependent dna ligase.	1999	10407164
detection of antimicrobial activity in urine for epidemiologic studies of antibiotic use.	antibiotic resistance is the inevitable consequence of the selective pressure of antimicrobial drug use and the adaptive plasticity of the microorganisms. excessive and irrational use of antimicrobial drugs is a problem in all countries. it is particularly troublesome in developing countries where there is a heavy burden of infectious diseases. this study was designed to determine whether detection of antimicrobial activity in the urine might be a useful tool for epidemiologic studies of the int ...	1999	10408993
thermostable alpha-galactosidase from bacillus stearothermophilus nub3621: cloning, sequencing and characterization.	an alpha-galactosidase gene from the thermophilic bacterium bacillus stearothermophilus nub3621 was cloned, sequenced, expressed in escherichia coli and the recombinant protein was purified. the bacillus enzyme, designated agan, is similar to alpha-galactosidases of family 36 in the classification of glycosyl hydrolases. the enzyme was estimated to be a tetramer with a molecular mass of subunits 80.3 kda. the purified agan is thermostable and has a temperature optimum of activity at 75 degrees c ...	1999	10418141
organophosphorus acid anhydrolase in slime mold, duckweed and mung bean: a continuing search for a physiological role and a natural substrate.	recently, and for the first time, a diisopropylphosphorofluoridate (dfp)-hydrolyzing enzyme, i.e. an organophosphorus acid anhydrolase (opaa), has been reported in a plant-source. based on this and other suggestive evidence, the ability of three plant sources and a protist to hydrolyze dfp and 1,2,2-trimethylpropyl methylphosphonofluoridate (soman) were tested, and the effects of mn2+ and ethylenediamine tetraacetate (edta) on this activity. the plants are duckweed (lemna minor), giant duckweed ...	1999	10421476
establishing the independent culture of a strictly symbiotic bacterium symbiobacterium thermophilum from its supporting bacillus strain.	symbiobacterium thermophilum is a strictly symbiotic thermophile, the growth of which is dependent on the coexistence of an associating thermophilic bacillus sp., strain s. s. thermophilum grows only in mixed culture with the bacillus strain in liquid media, and does not form visible colonies on solid media. to measure the growth of this symbiotic bacterium and to analyze its growth requirements, we developed a quantitative pcr method by using its specific sequences in a putative membrane transl ...	1999	10427695
structural studies of the bstvi restriction-modification proteins by fluorescence spectroscopy.	structural studies of the proteins of the bstvi restriction-modification system of bacillus stearothermophilus v were carried out using intrinsic fluorescence techniques. the exposure and environments of their tryptophanyl residues were determined using collisional quenchers. quenching of bstvi endonuclease by iodide suggested a heterogeneous class of tryptophan residues, while the results obtained with m.bstvi methylase were consistent with a rather exposed tryptophan population. a comparison o ...	1999	10429188
sporicidal activity of a new low-temperature sterilization technology: the sterrad 50 sterilizer.	this study was undertaken to evaluate the efficacy of a new low-temperature sterilization system that recently has been cleared by the food and drug administration, the sterrad 50. flat stainless steel carriers were inoculated with approximately 10(6) bacillus stearothermophilus spores. these carriers were placed aseptically in the middle of 40-cm-long stainless steel-lumened test units of varying diameters (1 mm, 2 mm, and 3 mm). after inoculation, the test units were processed in the sterrad 5 ...	1999	10432166
the diacetamidodideoxyuronic-acid-containing glycan chain of bacillus stearothermophilus nrs 2004/3a represents the secondary cell-wall polymer of wild-type b. stearothermophilus strains.	the diacetamidodideoxymannuronic-acid-containing glycan of bacillus stearothermophilus nrs 2004/3a with the repeating unit structure [-->4)-beta-d-manpa2,3(nac)2-(1-->6)-alpha-d-glcp-(1-->4)-beta-d-+ ++manpa2,3 (nac)2-(1-->3)-alpha-d-glcpnac-(1-->], was examined to identify its linkage to the bacterial cell wall. in a previous paper it was suggested that this glycan is covalently linked to the surface layer (s-layer) glycoprotein of that organism. by improved chromatographic techniques (gel perm ...	1999	10439396
production of alpha-amylase in fed-batch cultures of vgb+ and vgb- recombinant escherichia coli: some observations.	synthesis and excretion of bacillus stearothermophilus alpha-amylase is analyzed in fed-batch cultivations of escherichia coli jm103[pmk79] and e. coli jm103[pmk57], the former strain containing the plasmid-encoded vitreoscilla hemoglobin (vhb) gene (vgb) and the latter strain being devoid of this gene. fed-batch operation is observed to be substantially superior to batch operation as concerns the alpha-amylase production rate and the extent of excretion of the enzyme. faster feeding of a nutrie ...	1999	10441355
thermal unfolding of phosphorylating d-glyceraldehyde-3-phosphate dehydrogenase studied by differential scanning calorimetry.	thermal unfolding parameters were determined for a two-domain tetrameric enzyme, phosphorylating d-glyceraldehyde-3-phosphate dehydrogenase (gapdh), and for its isolated nad(+)-binding domain. at ph 8.0, the transition temperatures (t(max)) for the apoforms of the native bacillus stearothermophilus gapdh and the isolated domain were 78.3 degrees c and 61.9 degrees c, with calorimetric enthalpies (deltah(cal)) of 4415 and 437 kj/mol (or 30.7 and 22.1 j/g), respectively. in the presence of nearly ...	1999	10446379
mutational analysis of the thermostable arginine repressor from bacillus stearothermophilus: dissecting residues involved in dna binding properties.	recently the crystal structure of the dna-unbound form of the full-length hexameric bacillus stearothermophilus arginine repressor (argr) has been resolved, providing a possible explanation for the mechanism of arginine-mediated repressor-operator dna recognition. in this study we tested some of these functional predictions by performing site-directed mutagenesis of distinct amino acid residues located in two regions, the n-terminal dna-binding domain and the c-terminal oligomerization domain of ...	1999	10452892
thermal inactivation kinetics of bacillus stearothermophilus spores using a linear temperature program.	a systematic study of the inactivation kinetics of bacillus stearothermophilus spores was carried out in nonisothermic heating conditions using a linear temperature increase program and analyzing the experimental data by means of a one-step nonlinear regression. the d and z values estimated are close to those obtained in isothermic conditions and estimated by using a two-step model, first d values are calculated, and then in the second step a z value is deduced (d(121 degrees c) = 3.08 and 4.38 ...	1999	10456754
characterization of a novel stable biocatalyst obtained by protein engineering.	protein engineering is a powerful tool for the improvement of the properties of biocatalysts. previously we have applied protein engineering technologies to obtain an extremely stable variant of the thermolysin-like protease from bacillus stearothermophilus [van den burg, vriend, veltman, venema and eijsink (1998) proc. natl. acad. sci. u.s.a. 95, 2056-2060]. this variant is much more resistant to denaturing conditions (temperature and denaturing agents) than the wild-type enzyme. an extensive e ...	1999	10467116
protein design of geranyl diphosphate synthase. structural features that define the product specificities of prenyltransferases.	geranyl diphosphate synthase catalyzes the condensation of isopentenyl diphosphate with dimethylallyl diphosphate to give a c(10) compound, geranyl diphosphate, which is a precursor of all monoterpenoids. however, the gene has not been isolated from any organisms. to examine the possibility that geranyl diphosphate synthase has evolved from a common ancestor of the prenyltransferase family and to predict the active site structure, we tried to convert bacillus stearothermophilus farnesyl diphosph ...	1999	10467173
identification of a virulence-associated protein homolog gene and isra1 in a plasmid of riemerella anatipestifer.	riemerella anatipestifer is the causative agent of polyserositis of ducks and geese. we have previously reported that a 3.9-kb plasmid, pcfc1, carries protein genes (vapd1 and vapd2) that are similar to virulence-associated genes of other bacteria. in the present study, we report the complete sequence of a second plasmid of 5.6 kb, pcfc2. pcfc2 has a 28% g-c content and three large open reading frames (orfs). one of the orfs (designated asvapd1) encodes a polypeptide that shares 53.9, 53.9, 48.3 ...	1999	10481080
the electric dipole moment of dna-binding hu protein calculated by the use of an nmr database.	electric birefringence measurements indicated the presence of a large permanent dipole moment in hu protein-dna complex. in order to substantiate this observation, numerical computation of the dipole moment of hu protein homodimer was carried out by using nmr protein databases. the dipole moments of globular proteins have hitherto been calculated with x-ray databases and nmr data have never been used before. the advantages of nmr databases are: (a) nmr data are obtained, unlike x-ray databases, ...	1999	10483709
functional characterization of the phosphorylating d-glyceraldehyde 3-phosphate dehydrogenase from the archaeon methanothermus fervidus by comparative molecular modelling and site-directed mutagenesis.	phosphorylating archaeal d-glyceraldehyde 3-phosphate dehydrogenases (grap-dhs) share only 15-20% identity with their glycolytic bacterial and eukaryotic counterparts. unlike the latter which are nad-specific, archaeal grap-dhs exhibit a dual-cofactor specificity with a marked preference for nadp. in the present study, we have constructed a three-dimensional model of the methanothermus fervidus grap-dh based upon the x-ray structures of the bacillus stearothermophilus and escherichia coli grap-d ...	1999	10491162
refining the overall structure and subdomain orientation of ribosomal protein s4 delta41 with dipolar couplings measured by nmr in uniaxial liquid crystalline phases.	prokaryotic protein s4 initiates assembly of the small ribosomal subunit by binding to 16 s rrna. residues 43-200 of s4 from bacillus stearothermophilus (s4 delta41) bind to both 16 s rrna and to a mrna pseudoknot. in order to obtain structure-based insights regarding rna binding, we previously determined the solution structure of s4 delta41 using noe, hydrogen bond, and torsion angle restraints. s4 delta41 is elongated, with two distinct subdomains, one all helical, the other including a beta-s ...	1999	10493882
tyrosine 265 of alanine racemase serves as a base abstracting alpha-hydrogen from l-alanine: the counterpart residue to lysine 39 specific to d-alanine.	alanine racemase of bacillus stearothermophilus has been proposed to catalyze alanine racemization by means of two catalytic bases: lysine 39 (k39) abstracting specifically the alpha-hydrogen of d-alanine and tyrosine 265 (y265) playing the corresponding role for the antipode l-alanine. the role of k39 as indicated has already been verified [watanabe, a., kurokawa, y., yoshimura, t., kurihara, t., soda, k., and esaki, n. (1999) j. biol. chem. 274, 4189-4194]. we here present evidence for the fun ...	1999	10502689
bacterial cell envelopes (ghosts) but not s-layers activate human endothelial cells (huvecs) through scd14 and lbp mechanism.	bacterial cell-envelopes (called ghosts) and surface layers (s-layers) are discussed to be used as vaccines and/or adjuvants, consequently it is necessary to find out which immunomodulatory mediators are induced in human cells. the present work focuses on the effects of ghosts (escherichia coli o26:b6), s-layers (bacillus stearothermophilus) in comparison with lps and antibiotic-inactivated whole bacteria (e. coli o26:b6) on human umbilical vein endothelial cells (huvec) with regard to the relea ...	1999	10519933
the fmet-trna binding domain of translational initiation factor if2: role and environment of its two cys residues.	mutations of the cysteines (positions 668 and 714) were generated in the if2 c domain of bacillus stearothermophilus translation initiation factor if2. the corresponding proteins were characterized functionally and structurally. most (yet not all) amino acid replacements at both positions resulted in severe reduction of the fmet-trna binding activity of if2 c without grossly altering its structure. our work demonstrates that: (a) both cys residues are buried within an hydrophobic core and not ac ...	1999	10526160
phosphorylation of ribosomal protein l18 is required for its folding and binding to 5s rrna.	ribosomal protein l18 from bacillus stearothermophilus (bl18) includes a previously unreported phosphoserine residue. the folded conformation of the protein is stabilized by the dianionic form of the phosphate group of that residue. in the absence of mg2+, the pk(a) of the phosphate group is so high that the protein is not fully folded at ph 7. in the presence of mg2+, its pk(a) drops significantly, and consequently the native conformation of bl18 becomes stable at ph 7 and the protein is able t ...	1999	10529214
identification by subtractive hybridization of a novel insertion sequence specific for virulent strains of porphyromonas gingivalis.	subtractive hybridization was employed to isolate specific genes from virulent porphyromonas gingivalis strains that are possibly related to abscess formation. the genomic dna from the virulent strain p. gingivalis w83 was subtracted with dna from the avirulent strain atcc 33277. three clones unique to strain w83 were isolated and sequenced. the cloned dna fragments were 885, 369, and 132 bp and had slight homology with only bacillus stearothermophilus is5377, which is a putative transposase. th ...	1999	10531208
structure of ribosomal protein l30 from thermus thermophilus at 1.9 a resolution: conformational flexibility of the molecule.	the crystal structure of ribosomal protein l30 from the extreme thermophilic bacterium thermus thermophilus has been determined at 1. 9 a resolution. the crystals are trigonal and belong to space group p3(2)21, with unit-cell parameters a = b = 63.5, c = 77.8 a, alpha = beta = 90, gamma = 120 degrees and two molecules per asymmetric unit. the structure was solved by the molecular-replacement method with amore and refined with x-plor to an r value of 20.3% and an r(free) of 25.3% in the resolutio ...	1999	10531479
crystallization and preliminary x-ray diffraction analysis of the homodimeric form alpha2 of the hu protein from escherichia coli.	the homodimeric form alpha(2) of the escherichia coli dna-binding protein hu was crystallized by the hanging-drop vapour-diffusion method using peg 4000 as a precipitant. the crystals belong to space group i222, with unit-cell parameters a = 31.09, b = 55.34, c = 117. 63 a, and contain one monomer per asymmetric unit. a full diffraction data set was collected to 2.3 a resolution on a conventional x-ray source. the molecular-replacement method, using the hu crystallographic model from bacillus st ...	1999	10531506
site-directed mutagenesis of the conserved residues in component i of bacillus subtilis heptaprenyl diphosphate synthase.	heptaprenyl diphosphate synthase of bacillus subtilis is composed of two dissociable heteromeric subunits, component i and component ii. component ii has highly conserved regions typical of (e)-prenyl diphosphate synthases, but it shows no prenyltransferase activity alone unless it is combined with component i. alignment of amino acid sequences for component i and the corresponding subunits of bacillus stearothermophilus heptaprenyl diphosphate synthase and micrococcus luteus b-p 26 hexaprenyl d ...	1999	10545188
comparative study of the inhibition of alpha-glucosidase, alpha-amylase, and cyclomaltodextrin glucanosyltransferase by acarbose, isoacarbose, and acarviosine-glucose.	bacillus stearothermophilus maltogenic amylase hydrolyzes the first glycosidic linkage of acarbose to give acarviosine-glucose. in the presence of carbohydrate acceptors, acarviosine-glucose is primarily transferred to the c-6 position of the acceptor. when d-glucose is the acceptor, isoacarbose is formed. acarbose, acarviosine-glucose, and isoacarbose were compared as inhibitors of alpha-glucosidase, alpha-amylase, and cyclomaltodextrin glucanosyltransferase. the three inhibitors were found to ...	1999	10545215
transglycosylation of naringin by bacillus stearothermophilusmaltogenic amylase to give glycosylated naringin.	naringin, a bitter compound in citrus fruits, was transglycosylated by bacillus stearothermophilus maltogenic amylase reaction with maltotriose to give a series of mono-, di-, and triglycosylnaringins. glycosylation products of naringin were observed by tlc and hplc. the major glycosylation product was purified by using a sephadex lh-20 column. the sturcture was determined by using maldi-tof ms, methylation analysis, and (1)h and (13)c nmr. the major transglycosylation product was maltosylnaring ...	1999	10552702
phosphorylated aspartate in the structure of a response regulator protein.	phosphorylation of aspartic acid residues is the hallmark of two- component signal transduction systems that orchestrate the adaptive responses of micro-organisms to changes in their surroundings. two-component systems consist of a sensor kinase that interprets environmental signals and a response regulator that activates the appropriate physiological response. although structures of response regulators are known, little is understood about their activated phosphorylated forms, due to the intrin ...	1999	10556024
redesign of the coenzyme specificity in l-lactate dehydrogenase from bacillus stearothermophilus using site-directed mutagenesis and media engineering.	l-lactate dehydrogenase (ldh) from bacillus stearothermophilus is a redox enzyme which has a strong preference for nadh over nadph as coenzyme. to exclude nadph from the coenzyme-binding pocket, ldh contains a conserved aspartate residue at position 52. however, this residue is probably not solely responsible for the nadh specificity. in this report we examine the possibilities of altering the coenzyme specificity of ldh by introducing a range of different point mutations in the coenzyme-binding ...	1999	10556245
role of the n-terminal region of ribosomal protein s7 in its interaction with 16s rrna which binds to the concavity formed by the beta-ribbon arm and the alpha-helix.	the ribosomal protein s7, a primary 16s rrna-binding protein, plays an essential role in stabilizing the 3' major domain of 16s rrna and also in feedback regulation of the str operon, as a translational repressor. we examined amino acid residues in ribosomal protein s7 from bacillus stearothermophilus (bsts7) that are essential for 16s rrna binding. truncation of the n-terminal 10 residues of bsts7 abolished its binding to 16s rrna, whereas removal of the c-terminal eight residues had no effect ...	1999	10561602
chloride affects the interaction between tyrosyl-trna synthetase and trna.	the physiological concentration of free magnesium in escherichia coli cells is about 1 mm, and there is almost no chloride in the cell. when the aminoacylation of trna by tyrosyl-trna synthetase was assayed at 1 mm free mg2+, chloride (and sulphate) ions inhibited the reaction but acetate at the same concentration (< 200 mm) was not inhibitory. when the magnesium concentration was increased to 10 mm there was almost no chloride inhibition any more. chloride strengthened the ppi inhibition, the k ...	1999	10572925
self-assembly and catalytic activity of the pyruvate dehydrogenase multienzyme complex from bacillus stearothermophilus.	the pyruvate dehydrogenase multienzyme complex from bacillus stearothermophilus was reconstituted in vitro from recombinant proteins derived from genes over-expressed in escherichia coli. titrations of the icosahedral (60-mer) dihydrolipoyl acetyltransferase (e2) core component with the pyruvate decarboxylase (e1, alpha2beta2) and dihydrolipoyl dehydrogenase (e3, alpha2) peripheral components indicated a variable composition defined predominantly by tight and mutually exclusive binding of e1 and ...	1999	10583411
biochemical and phylogenetic analyses of a cold-active beta-galactosidase from the lactic acid bacterium carnobacterium piscicola ba.	we are investigating glycosyl hydrolases from new psychrophilic isolates to examine the adaptations of enzymes to low temperatures. a beta-galactosidase from isolate ba, which we have classified as a strain of the lactic acid bacterium carnobacterium piscicola, was capable of hydrolyzing the chromogen 5-bromo-4-chloro-3-indolyl beta-d-galactopyranoside (x-gal) at 4 degrees c and possessed higher activity in crude cell lysates at 25 than at 37 degrees c. sequence analysis of a cloned dna fragment ...	1999	10584002
three domains comprised in thermostable molecular weight 54,000 pullulanase of type i from bacillus flavocaldarius kp1228.	the gene that coded for a cellular pullulanase of type i (alpha-dextrin 6-glucanohydrolase, ec 3.2.1.41) in bacillus flavocaldarius kp1228 (ferm-p9542) cells growing at 51 to 82 degrees c was expressed in escherichia coli mv1184. the enzyme had a half-life of 10 min at 107 degrees c. purification of the enzyme and its characterization showed that the enzyme was identical with the native one. its primary structure of 475 residues with a molecular weight of 53,856 deduced from the gene was 15-21% ...	1999	10586502
dimers generated from tetrameric phosphorylating glyceraldehyde-3-phosphate dehydrogenase from bacillus stearothermophilus are inactive but exhibit cooperativity in nad binding.	tetrameric phosphorylating glyceraldehyde-3-phosphate dehydrogenase (gapdh) from bacillus stearothermophilus has been described as a "dimer of dimers" with three nonequivalent interfaces, p-axis (between subunits o and p and between subunits q and r), q-axis (between subunits o and q and between subunits p and r), and r-axis interface (between subunits o and r and between subunits p and q). o-p dimers, the most stable and the easiest to generate, have been created by selective disruption of hydr ...	1999	10587431
a conserved serine-rich stretch in the glutamate transporter family forms a substrate-sensitive reentrant loop.	neuronal and glial glutamate transporters remove the excitatory neurotransmitter glutamate from the synaptic cleft. the proteins belong to a large family of secondary transporters, which includes bacterial glutamate transporters. the c-terminal half of the glutamate transporters is well conserved and thought to contain the translocation path and the binding sites for substrate and coupling ions. a serine-rich sequence motif in this part of the proteins is located in a putative intracellular loop ...	1999	10588697
effect of acidification and oil on the thermal resistance of bacillus stearothermophilus spores heated in food substrate.	the effect of the addition of vinegar and/or oil to a food homogenate (tomato sauce, tuna and vegetables) on the thermal resistance of bacillus stearothermophilus spores was studied. the results indicated that the food substrate without the addition of vinegar and oil and a ph value of 5.28 reduced the thermal resistance of b. stearothermophilus spores compared with that obtained in double-distilled water, (d121 = 1.41 and 3.08 min respectively). the addition of vinegar reduced the ph of the sub ...	1999	10733251
purification and properties of genetic expressing product of thermostable protease from bacillus stearothermophilus hy-69.	the thermostable metal protease gene from bacillus stearothermophilus hy-69 had been cloned and expressed in bacillus subtilis mi113. the genetic expressing product of the enzyme was purified by cm-cellulose chromatography. the product shows homogeneity on page. its molecular weight is 27,000 +/- 1000 by sds-page and sephadex g100 filtration, respectively. the alpha-helix content of the protease is estimated to be about 66%, the beta-turn about 28%, the random coil about 6%, but not beta-sheet, ...	1999	10668130
effect of temperature on the saccharide composition obtained after alpha-amylolysis of starch	the hydrolysis of starch to low-molecular-weight products (normally characterised by their dextrose equivalent (de), which is directly related to the number-average molecular mass) was studied at different temperatures. amylopectin potato starch, lacking amylose, was selected because of its low tendency towards retrogradation at lower temperatures. bacillus licheniformis alpha-amylase was added to 10% [w/w] gelatinised starch solutions. the hydrolysis experiments were done at 50, 70, and 90 degr ...	1999	10099614
secondary structure of the c-terminal domain of the tyrosyl-transfer rna synthetase from bacillus stearothermophilus: a novel type of anticodon binding domain?	the tyrosyl-trna synthetase catalyzes the activation of tyrosine and its coupling to the cognate trna. the enzyme is made of two domains: an n-terminal catalytic domain and a c-terminal domain that is necessary for trna binding and for which it was not possible to determine the structure by x-ray crystallography. we determined the secondary structure of the c-terminal domain of the tyrosyl-trna synthetase from bacillus stearothermophilus by nuclear magnetic resonance methods and found that it is ...	1999	10100619
self-assembly product formation of the bacillus stearothermophilus pv72/p6 s-layer protein sbsa in the course of autolysis of bacillus subtilis.	in order to achieve high level expression and to study the release of a protein capable of self-assembly, the gene encoding the crystalline cell surface (s-layer) protein sbsa of bacillus stearothermophilus pv72/p6, including its signal sequence, was cloned and expressed in bacillus subtilis. to obtain high level expression, a tightly regulated, xylose-inducible, stably replicating multicopy-plasmid vector was constructed. after induction of expression, the s-layer protein made up about 15% of t ...	1999	10188248
evidence for a two-base mechanism involving tyrosine-265 from arginine-219 mutants of alanine racemase.	a positively charged residue, r219, was found to interact with the pyridine nitrogen of pyridoxal phosphate in the structure of alanine racemase from bacillus stearothermophilus [shaw et al. (1997) biochemistry 36, 1329-1342]. three site-directed mutants, r219k, r219a, and r219e, have been characterized and compared to the wild type enzyme (wt) to investigate the role of r219 in catalysis. the r219k mutation is functionally conservative, retaining approximately 25% of the wt activity. the r219a ...	1999	10194319
nativelike structure and stability in a truncation mutant of a protein minidomain: the peripheral subunit-binding domain.	despite its small size, the peripheral subunit-binding domain from the dihydrolipoamide acetyltransferase component of the bacillus stearothermophilus pyruvate dehydrogenase multienzyme complex adopts a unique, compact structure. to determine whether the full 43 residue sequence is required for the domain to adopt a stable, nativelike structure, 3 proteins of different lengths were prepared. psbd41 corresponds to residues 3-43 of the domain, psbd36 spans residues 6-41, and psbd33 comprises resid ...	1999	10194328
high-resolution crystals of the hu mutant k38n from bacillus stearothermophilus.	the dna-binding protein hu is ubiquitous in the prokaryotic cell. it is a major protein component of isolated nucleoids and is believed to control the tertiary structure of prokaryotic dna. the bacillus stearothermophilus hu (bsthu) mutants obtained by mutagenesis have been investigated. crystallization experiments of bsthu-k38n (lys38 is substituted with asn) resulted in two forms of crystals suitable for high-resolution x-ray analysis. the first form belongs to the monoclinic space group c2 wi ...	1999	10196119
cloning of a tellurite resistance determinant from bacillus stearothermophilus v in escherichia coli.	a potassium tellurite-resistance determinant was isolated from bacillus stearothermophilus v and cloned in escherichia coli. transformed cells formed black colonies when grown on solid media containing permissive tellurite concentrations. the resistance determinant was contained in a b. stearothermophilus v chromosomal dna fragment of 7 kb.	1999	10205661
stabilizing effect of an s-layer on liposomes towards thermal or mechanical stress.	isolated subunits of the crystalline cell surface layer (s-layer) protein of bacillus stearothermophilus pv72/p2 were recrystallized on positively charged unilamellar liposomes. liposomes were composed of dipalmitoylphosphatidylcholine (dppc), cholesterol and hexadecylamine (hda) in a molar ratio of 10:5:4 and they were prepared by the dehydration-rehydration method followed by an extrusion procedure. the s-layer protein to dppc ratio was 5.7 nmol/micromol which approximately corresponds to the ...	1999	10209215
characterization and modelling of vant: a novel, membrane-bound, serine racemase from vancomycin-resistant enterococcus gallinarum bm4174.	sequence determination of a region downstream from the vanxyc gene in enterococcus gallinarum bm4174 revealed an open reading frame, designated vant, that encodes a 698-amino-acid polypeptide with an amino-terminal domain containing 10 predicted transmembrane segments. the protein contained a highly conserved pyridoxal phosphate attachment site in the c-terminal domain, typical of alanine racemases. the protein was overexpressed in escherichia coli, and serine racemase activity was detected in t ...	1999	10209740
probing the location and function of the conserved histidine residue of phosphoglucose isomerase by using an active site directed inhibitor n-bromoacetylethanolamine phosphate.	phosphoglucose isomerase (ec 5.3.1.9) catalyzes the interconversion of d-glucopyranose-6-phosphate and d-fructofuranose-6-phosphate by promoting an intrahydrogen transfer between c1 and c2. a conserved histidine exists throughout all phosphoglucose isomerases and was hypothesized to be the base catalyzing the isomerization reaction. in the present study, this conserved histidine, his311, of the enzyme from bacillus stearothermophilus was subjected to mutational analysis, and the mutational effec ...	1999	10595547
molecular recognition of tyrosinyl adenylate analogues by prokaryotic tyrosyl trna synthetases.	molecular modelling and synthetic studies have been carried out on tyrosinyl adenylate and analogues to probe the interactions seen in the active site of the x-ray crystal structure of tyrosyl trna synthetase from bacillus stearothermophilus, and to search for new inhibitors of this enzyme. micromolar and sub-micromolar inhibitors of tyrosyl trna synthetases from both b. stearothermophilus and staphylococcus aureus have been synthesised. the importance of the adenine ring to the binding of tyros ...	1999	10632057
bacillus stearothermophilus lctb gene gives rise to functional k+ channels in escherichia coli and in xenopus oocytes.	we have cloned a small k+ channel subunit (lctb) of the gram-positive bacterium bacillus stearothermophilus (b. stearo.). the b. stearo. lctb protein is only 134 amino acids long. the sequence contains a typical k+ channel p-domain with a k+ channel gygd signature sequence and two hydrophobic, possibly membrane-spanning segments m1 and m2. unexpectedly, lctb k+ channels exhibited properties which differed markedly from the ones reported for kcsa channels of the gram-positive bacterium streptomyc ...	1999	10635064
towards regioselective synthesis of oligosaccharides by use of alpha-glucosidases with different substrate specificity.	alpha-glucosidase from two microbial sources, bacillus stearothermophilus and brewer's yeast, has been used to catalyze transglycosylation reactions and a comparative study was carried out to determine the regioselectivity of this reaction. bacterial alpha-glucosidase exhibited higher transfer activity with maltose and was able to synthesize tri- and tetrasaccharides in high yield (27%). in the case of yeast enzyme, only trisaccharides were synthesized in lower yield. structure analysis of trans ...	1999	10637985
role of lysine 39 of alanine racemase from bacillus stearothermophilus that binds pyridoxal 5'-phosphate. chemical rescue studies of lys39 --> ala mutant.	the lysine residue binding with the cofactor pyridoxal 5'-phosphate (plp) plays an important role in catalysis, such as in the transaldimination and abstraction of alpha-hydrogen from a substrate amino acid in plp-dependent enzymes. we studied the role of lys39 of alanine racemase (ec 5.1.1.1) from bacillus stearothermophilus, the plp-binding residue of the enzyme, by replacing it site-specifically with alanine and characterizing the resultant k39a mutant enzyme. the mutant enzyme turned out to ...	1999	9933615
experimental evolution of a dense cluster of residues in tyrosyl-trna synthetase: quantitative effects on activity, stability and dimerization.	a dense cluster of eight residues was identified at the crossing of two alpha-helices in tyrosyl-trna synthetase (tyrrs) from the thermophile bacillus stearothermophilus. its mechanism of evolution was characterized. four residues of this cluster are not conserved in tyrrs from the mesophile escherichia coli. the corresponding mutations were constructed in tyrrs(delta1), a derivative of tyrrs from b. stearothermophilus in which the anticodon binding domain is deleted. mutations i52l (i.e. ile52 ...	1999	9973571
the bacillus stearothermophilus mannitol regulator, mtlr, of the phosphotransferase system. a dna-binding protein, regulated by hpr and iicbmtl-dependent phosphorylation.	d-mannitol is taken up by bacillus stearothermophilus and phosphorylated via a phosphoenolpyruvate-dependent phosphotransferase system (pts). the genes involved in the mannitol uptake were recently cloned and sequenced. one of the genes codes for a putative transcriptional regulator, mtlr. the presence of a dna binding helix-turn-helix motif and two antiterminator-like pts regulation domains, suggest that mtlr is a dna-binding protein, the activity of which can be regulated by phosphorylation by ...	1999	9988713
principles of quasi-equivalence and euclidean geometry govern the assembly of cubic and dodecahedral cores of pyruvate dehydrogenase complexes.	the pyruvate dehydrogenase multienzyme complex (mr of 5-10 million) is assembled around a structural core formed of multiple copies of dihydrolipoyl acetyltransferase (e2p), which exhibits the shape of either a cube or a dodecahedron, depending on the source. the crystal structures of the 60-meric dihydrolipoyl acyltransferase cores of bacillus stearothermophilus and enterococcus faecalis pyruvate dehydrogenase complexes were determined and revealed a remarkably hollow dodecahedron with an outer ...	1999	9990008