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complete measurement of the pka values of the carboxyl and imidazole groups in bacillus circulans xylanase.electrostatic interactions in proteins can be dissected experimentally by determining the pka values of their constituent ionizable amino acids. to complement previous studies of the glutamic acid and histidine residues in bacillus circulans xylanase (bcx), we have used nmr methods to measure the pka s of the seven aspartic acids and the c-terminus of this protein. the pka s of these carboxyls are all less than the corresponding values observed with random coil polypeptides, indicating that thei ...19979416621
characterization of a buried neutral histidine in bacillus circulans xylanase: internal dynamics and interaction with a bound water molecule.nmr spectroscopy was used to characterize the dynamic behavior of his149 in bacillus circulans xylanase (bcx) and its interaction with an internal water molecule. rate constants for the specific acid- and base-catalyzed exchange following bimolecular kinetics (ex2) of the nitrogen-bonded h epsilon 2 of this buried, neutral histidine were determined. at pdmin 7.0 and 30 degrees c, the lifetime for this proton is 9.9 h, corresponding to a protection factor of approximately 10(7) relative to that p ...19989485306
extracellular dextran-induced p-nitrophenyl-alpha-d-glucoside-hydrolyzing enzyme of bacillus circulans ka-304: a producer of schizophyllum commune-lytic enzyme.p-np-alpha-d-glucoside-hydrolyzing activity in the culture filtrate of bacillus circulans ka-304, a producer of schizophyllum commune cell-wall lytic enzyme, increased remarkably when the bacterium was grown on dextran as a carbon source. it was suggested that the increase of the activity was caused by increases of two major species, alpha-d-glucosidase i and alpha-d-glucosidase ii. alpha-d-glucosidase i, which showed a certain reactivity toward dextran, was isolated from the filtrate (mw 70 kda ...19989532804
chemo-enzymatic synthesis of galactosylmaltooligosaccharidonolactone as a substrate analogue inhibitor for mammalian alpha-amylase.we performed chemo-enzymatic transformation of maltooligosaccharides into both end-modified oligosaccharidonolactones of potential use as substrate analogue inhibitors for mammalian alpha-amylases. enzymatic modification of the non-reducing end glucosyl residue of the maltooligosaccharide was first performed by transglycosylation with beta-d-galactosidase from bacillus circulans. when maltotriose and maltotetraose were the acceptors, the enzyme regioselectively synthesized 4(3)-o-beta-d-galactos ...19989538235
enzymatic synthesis of 4-o-beta-d-galactopyranosyl-moranoline and 3-o-beta-d-galactopyranosyl-moranoline by using beta-galactosidase from bacillus circulans.a transgalactosylation reaction from lactose to moranoline (1-deoxynojirimycin) was accomplished by using beta-galactosidase [ec 3.2.1.23] from bacillus circulans. the enzyme formed 3-o-beta-d-galactopyranosyl-moranoline and 4-o-beta-d-galactopyranosyl-moranoline as major products, together with 2-o-beta-d-galactopyranosyl-moranoline and 6-o-beta-d-galactopyranosyl-moranoline as minor ones.19968829541
xylanase homology modeling using the inverse protein folding approach.xylanase has been used in wood pulp bleaching in an effort to reduce chlorine release into the environment and pollution associated with paper production. the three-dimensional structure of xylanase is important to enable better understanding of the enzyme mechanism and to help design a more thermostable xylanase mutant. at the time this work was begun, there was no sequence homologous protein available for traditional sequence-based homology modeling. in order to circumvent this problem, the in ...19968845760
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 ...199910387084
characterization of a buried neutral histidine residue in bacillus circulans xylanase: nmr assignments, ph titration, and hydrogen exchange.bacillus circulans xylanase contains two histidines, one of which (his 156) is solvent exposed, whereas the other (his 149) is buried within its hydrophobic core. his 149 is involved in a network of hydrogen bonds with an internal water and ser 130, as well as a potential weak aromatic-aromatic interaction with tyr 105. these three residues, and their network of interactions with the bound water, are conserved in four homologous xylanases. to probe the structural role played by his 149, nmr spec ...19968931150
comparative phylogeny of rrs and nifh genes in the bacillaceae.the rrs (16s rdna) gene sequences of nitrogen-fixing endospore-forming bacilli isolated from the rhizosphere of wheat and maize were determined in order to infer their phylogenetic position in the bacillaceae. these rhizosphere strains form a monophyletic cluster with paenibacillus azotofixans, paenibacillus polymyxa and paenibacillus macerans. two of them (rsa19 and tod45) had previously been identified as bacillus circulans (group 2) by phenotypic characterization (api 50ch). evidence for nitr ...199910425751
purification and characterization of chitinase from bacillus circulans no.4.1.bacillus circulans no.4.1 produced a high level of chitinase when cells were grown in tryptic soy broth supplemented with 0.3% colloidal chitin at 35 degrees c for 5 days. purification was carried out by protein precipitation with 80% saturation ammonium sulfate, anion-exchange chromatography with deae-sephacel, and gel filtration with sephadex g-100, sequentially. the purified enzyme could be demonstrated as a single band on sds-page, estimated to be 45 kda. this enzyme could hydrolyze colloida ...199910441726
separation and characterization of three beta-galactosidases from bacillus circulans.crude preparation of bacillus circulans beta-galactosidase is known to have a good transglycolytic activity. two isoforms of the enzyme have been described so far in the literature. aiming at separating these two forms to assess their relative contribution to the regioselectivity of transglycosylation, we observed the presence of a third isoform never described before. this paper deals with the isolation procedures of the three enzymes and a re-consideration of their properties. the estimated mo ...19989565691
trapping and characterization of the reaction intermediate in cyclodextrin glycosyltransferase by use of activated substrates and a mutant enzyme.cyclodextrin glycosyltransferases (cgtases) catalyze the degradation of starch into linear or cyclic oligosaccharides via a glycosyl transfer reaction occurring with retention of anomeric configuration. they are also shown to catalyze the coupling of maltooligosaccharyl fluorides. reaction is thought to proceed via a double-displacement mechanism involving a covalent glycosyl-enzyme intermediate. this intermediate can be trapped by use of 4-deoxymaltotriosyl alpha-fluoride (4dg3alphaf). this sub ...19979245426
a unique chitinase with dual active sites and triple substrate binding sites from the hyperthermophilic archaeon pyrococcus kodakaraensis kod1.we have found that the hyperthermophilic archaeon pyrococcus kodakaraensis kod1 produces an extracellular chitinase. the gene encoding the chitinase (chia) was cloned and sequenced. the chia gene was found to be composed of 3,645 nucleotides, encoding a protein (1,215 amino acids) with a molecular mass of 134,259 da, which is the largest among known chitinases. sequence analysis indicates that chia is divided into two distinct regions with respective active sites. the n-terminal and c-terminal r ...199910583986
galactosyl transfer onto p-nitrophenyl beta-d-glucoside using beta-d-galactosidase from bacillus circulans.beta-d-gal-(1-->4)-beta-d-glc-oc6h4no2-p and its isomers (beta-d-gal-(1-->3)-beta-d-glc-oc6h4no2-p and beta-d-gal-(1-->6)-beta-d-glc-oc6h4no2-p) were synthesized from lactose and beta-d-glc-oc6h4no2-p, using transglycosylation by the beta-d-galactosidase from bacillus circulans. this reaction was efficient enough for us to do a one-pot preparation of galactosyl-glucoside from lactose. the order of the production of the transfer products was (1-->4) > > (1-->3) > (1-->6) in the initial stage of t ...19979255974
structural and functional properties of low molecular weight endo-1,4-beta-xylanases.there are currently four crystal structures of low molecular weight endo-1,4-beta-xylanases (e.c.3.2.1.8), i.e. family g/11 xylanases, available at the brookhaven data bank: 2 xylanases from trichoderma reesei (törrönen et al., 1994; törrönen and rouvinen, 1995) and one from bacillus circulans and another from trichoderma harzianum (campbell et al., 1993). they consist of two beta-sheets and one alpha-helix and have been described to resemble a partly-closed right hand. the catalytic residues ar ...19979335170
engineering of cyclodextrin product specificity and ph optima of the thermostable cyclodextrin glycosyltransferase from thermoanaerobacterium thermosulfurigenes em1.the product specificity and ph optimum of the thermostable cyclodextrin glycosyltransferase (cgtase) from thermoanaerobacterium thermosulfurigenes em1 was engineered using a combination of x-ray crystallography and site-directed mutagenesis. previously, a crystal soaking experiment with the bacillus circulans strain 251 beta-cgtase had revealed a maltononaose inhibitor bound to the enzyme in an extended conformation. an identical experiment with the cgtase from t. thermosulfurigenes em1 resulted ...19989488711
cloning, sequence analysis, and expression in escherichia coli of a gene coding for an enzyme from bacillus circulans k-1 that degrades guar gum.a 2,048-bp nucleotide sequence containing a gene coding for an enzyme that degraded guar gum from bacillus circulans k-1 was identified by polymerase chain reaction walking. this g-gene consisted of 1,551 nucleotides coding for a protein with mr 55,242. the enzyme was overexpressed in escherichia coli jm109 cells by the cloning the g-gene downstream of the lac z promoter of puc19. the molecular mass of recombinant g-enzyme estimated by sds-page was 62 kda, close to that from strain k-1. analysis ...19989571781
kinetic isotope effect and reaction mechanism of 2-deoxy-scyllo-inosose synthase derived from butirosin-producing bacillus circulans.the mechanism of 2-deoxy-scyllo-inosose synthase reaction, a carbocycle formation step from d-glucose-6-phosphate in the biosynthesis of the 2-deoxystreptamine aglycon of clinically important aminocyclitol antibiotics, was investigated with a partially purified enzyme from butirosin-producing bacillus circulans sank 72073, nonlabeled and double-labeled d-[4-2h, 3-15o]glucose-6-phosphate were used for cross-over experiment, and the oxime-tms ether derivative of the 2-deoxy-scyllo-inosose product ...19979207913
single-column purification of free recombinant proteins using a self-cleavable affinity tag derived from a protein splicing element.a novel protein purification system has been developed which enables purification of free recombinant proteins in a single chromatographic step. the system utilizes a modified protein splicing element (intein) from saccharomyces cerevisiae (sce vma intein) in conjunction with a chitin-binding domain (cbd) from bacillus circulans as an affinity tag. the concept is based on the observation that the modified sce vma intein can be induced to undergo a self-cleavage reaction at its n-terminal peptide ...19979224900
reassessment of acarbose as a transition state analogue inhibitor of cyclodextrin glycosyltransferase.the binding of several different active site mutants of bacillus circulans cyclodextrin glycosyltransferase to the inhibitor acarbose has been investigated through measurement of ki values. the mutations represent several key amino acid positions, most of which are believed to play important roles in governing the product specificity of cyclodextrin glycosyltransferase. michaelis-menten parameters for the substrates alpha-maltotriosyl fluoride (alphag3f) and alpha-glucosyl fluoride (alphagf) wit ...19989860832
purification and characterization of 2-deoxy-scyllo-inosose synthase derived from bacillus circulans. a crucial carbocyclization enzyme in the biosynthesis of 2-deoxystreptamine-containing aminoglycoside antibiotics.the biosynthesis of 2-deoxystreptamine, the central aglycon of a major group of clinically important aminoglycoside antibiotics, commences with the initial carbocycle formation step from d-glucose-6-phosphate to 2-deoxy-scyllo-inosose. this crucial step is known to be catalyzed by 2-deoxy-scyllo-inosose synthase, which has not yet been characterized so far. reported in this paper is the first purification of 2-deoxy-scyllo-inosose synthase from butirosin-producing bacillus circulans sank 72073 t ...199910344560
purification and properties of recombinant beta-galactosidase from bacillus circulans.a gene encoding beta-galactosidase from bacillus circulans which had hydrolysis specificity for the beta1-3 linkage was expressed in escherichia coli. the beta-galactosidase was purified from crude cell lysates of e. coli by column chromatographies on resource q and sephacryl s-200 hr. the enzyme released galactose with high selectivity from oligosaccharides which had terminal beta1-3 linked galactose residues. however it did not hydrolyse beta1-4 linked galactooligosaccharides. moreover, galbet ...19989557875
mechanism of type 3 capsular polysaccharide synthesis in streptococcus pneumoniae.the glycosidic linkages of the type 3 capsular polysaccharide of streptococcus pneumoniae ([3)-beta-d-glcua-(1-->4)-beta-d-glc-(1-->](n)) are formed by the membrane-associated type 3 synthase (cps3s), which is capable of synthesizing polymer from udp sugar precursors. using membrane preparations of s. pneumoniae in an in vitro assay, we observed type 3 synthase activity in the presence of either mn(2+) or mg(2+) with maximal levels seen with 10-20 mm mn(2+). high molecular weight polymer synthes ...200010660543
pre-steady state kinetic analysis of an enzymatic reaction monitored by time-resolved electrospray ionization mass spectrometry.for the first time, the new technique of time-resolved electrospray ionization mass spectrometry (esi-ms) has been used to accurately measure the pre-steady state kinetics of an enzymatic reaction by monitoring a transient enzyme intermediate. the enzyme used to illustrate this approach, bacillus circulans xylanase, is a retaining glycosidase that hydrolyzes xylan or beta-xylobiosides through a double-displacement mechanism involving a covalent xylobiosyl-enzyme intermediate. a low steady state ...19989601025
molecular analysis of maleate cis-trans isomerase from thermophilic bacteria.several strains of thermophilic bacteria containing maleate cis-trans isomerase were isolated from soil samples and identified as bacillus stearothermophilus, bacillus circulans, bacillus brevis, and deleya halophila. the maleate cis-trans isomerase was purified and characterized from one of the isolated strains, b. stearothermophilus mi-102. the purified enzyme of strain mi-102 showed higher thermal stability than the enzyme of a mesophile, alcaligenes faecalis ifo13111. the seven maleate cis-t ...200010803955
expression and characterization of the chitin-binding domain of chitinase a1 from bacillus circulans wl-12.chitinase a1 from bacillus circulans wl-12 comprises an n-terminal catalytic domain, two fibronectin type iii-like domains, and a c-terminal chitin-binding domain (chbd). in order to study the biochemical properties and structure of the chbd, chbd(chia1) was produced in escherichia coli using a pet expression system and purified by chitin affinity column chromatography. purified chbd(chia1) specifically bound to various forms of insoluble chitin but not to other polysaccharides, including chitos ...200010809681
enzymatic synthesis, isolation, and analysis of novel alpha- and beta-galactosyl-cycloisomalto-octaoses.novel branched cycloisomalto-octaoses (ci8s) were enzymatically synthesized by transgalactosylation with alpha-galactosidase from coffee bean and beta-galactosidase preparations from penicillium multicolor and bacillus circulans, using melibiose and lactose as donor substrates, and ci8 which is a cyclic homogeneous oligosaccharide composed of eight glucose units bound by alpha-(1-->6)-linkages, as an acceptor. alpha-galactosyl-ci8s and beta-galactosyl-ci8s obtained were isolated and purified by ...19979648258
scan-rate dependence in protein calorimetry: the reversible transitions of bacillus circulans xylanase and a disulfide-bridge mutant.the stabilities of bacillus circulans xylanase and a disulfide-bridge-containing mutant (s100c/n148c) were investigated by differential scanning calorimetry (dsc) and thermal inactivation kinetics. the thermal denaturation of both proteins was found to be irreversible, and the apparent transition temperatures showed a considerable dependence upon scanning rate. in the presence of low (nondenaturing) concentrations of urea, calorimetric transitions were observed for both proteins in the second he ...19989684886
vana gene cluster in a vancomycin-resistant clinical isolate of bacillus circulans.we report on the cloning and sequencing of the vana gene cluster present in the glycopeptide-resistant clinical isolate bacillus circulans vr0709 (r. fontana, m. ligozzi, c. pedrotti, e. m. padovani, and g. cornaglia, eur. j. clin. microbiol. infect. dis. 16:473-474, 1997). the presence of a vana-related gene in vr0709 was demonstrated in a pcr assay which permitted the specific amplification of an internal segment of vana. southern blotting suggested that the vana gene was located in the chromo ...19989687406
c-terminal domain of beta-1,3-glucanase h in bacillus circulans iam1165 has a role in binding to insoluble beta-1,3-glucan.the deduced amino acid sequences of 72-kda beta-1,3-glucanase from bacillus circulans wl-12 (gica) and 91-kda enzyme from b. circulans iam1165 (bglh) are highly homologous, except that the latter has an additional long c-terminal region composed of 192 amino acid residues. two mutant enzymes (bgih deprived of the c-terminal region and gica with the c-terminal region added) were constructed. the enzymes possessing the c-terminal region bound more abundantly to pachyman (insoluble beta-1,3-glucan) ...19989738929
thermophilic xylanase from thermomyces lanuginosus: high-resolution x-ray structure and modeling studies.the crystal structure of the thermostable xylanase from thermomyces lanuginosus was determined by single-crystal x-ray diffraction. the protein crystallizes in space group p21, a = 40.96(4) a, b = 52. 57(5) a, c = 50.47 (5) a, beta = 100.43(5) degrees, z = 2. diffraction data were collected at room temperature for a resolution range of 25-1.55 a, and the structure was solved by molecular replacement with the coordinates of xylanase ii from trichoderma reesei as a search model and refined to a cr ...19989753433
expression of bacillus circulans teri-42 xylanase gene in bacillus subtilis.the xylanase gene of bacillus circulans teri-42 was cloned in both b. subtilis and escherichia coli. the enzyme activity was almost 87% higher in b. subtilis (pba7) than in e. coli (paq4). no cellulase activity was detected in the clones, b. subtilis (pba7) and e. coli (paq4). approximately 1120 u (80%) of the xylanase was secreted extracellularly by the clone b. subtilis (pba7) as compared to 79 u (88%) excreted in e. coli (paq4). in b. subtilis (pba7) the optimal xylanase activity was at ph 7. ...200010899547
structures of novel acidic galactooligosaccharides synthesized by bacillus circulans beta-galactosidase.the structures of acidic oligosaccharides synthesized by a transglycosylation reaction by bacillus circulans beta-galactosidase, using lactose as the galactosyl donor, and n-acetylneuraminic acid (neuac) and glucuronic acid (glcua) as the acceptors were investigated. acidic oligosaccharides thus synthesized were purified by anion exchange chromatography and charcoal chromatography. the ms and nmr studies indicated that the acidic oligosaccharides from neuac were gal beta-(1-->8)-neuac, gal beta- ...19989805383
thermostable chitosanase from bacillus sp. strain ck4: cloning and expression of the gene and characterization of the enzyme.a thermostable chitosanase gene from the environmental isolate bacillus sp. strain ck4, which was identified on the basis of phylogenetic analysis of the 16s rrna gene sequence and phenotypic analysis, was cloned, and its complete dna sequence was determined. the thermostable chitosanase gene was composed of an 822-bp open reading frame which encodes a protein of 242 amino acids and a signal peptide corresponding to a 30-kda enzyme. the deduced amino acid sequence of the chitosanase from bacillu ...200010966383
the crystal structure of beta-glucosidase from bacillus circulans sp. alkalophilus: ability to form long polymeric assemblies.family 1 of glycosyl hydrolases is a large and biologically important group of enzymes. a new three-dimensional structure of this family, beta-glucosidase from bacillus circulans sp. alkalophilus is reported here. this is the first structure of beta-glucosidase from an alkaliphilic organism. the model was determined by the molecular replacement method and refined to a resolution of 2.7 a. the quaternary structure of b. circulans sp. alkalophilus beta-glucosidase is an octamer and subunits of the ...200010675298
analysis of the essential cell division gene ftsl of bacillus subtilis by mutagenesis and heterologous complementation.the ftsl gene is required for the initiation of cell division in a broad range of bacteria. bacillus subtilis ftsl encodes a 13-kda protein with a membrane-spanning domain near its n terminus. the external c-terminal domain has features of an alpha-helical leucine zipper, which is likely to be involved in the heterodimerization with another division protein, divic. to determine what residues are important for ftsl function, we used both random and site-directed mutagenesis. unexpectedly, all che ...200010986263
rational design of cyclodextrin glycosyltransferase from bacillus circulans strain 251 to increase alpha-cyclodextrin production.cyclodextrin glycosyltransferases (cgtase) (ec 2.4.1.19) are extracellular bacterial enzymes that generate cyclodextrins from starch. all known cgtases produce mixtures of alpha, beta, and gamma-cyclodextrins. a maltononaose inhibitor bound to the active site of the cgtase from bacillus circulans strain 251 revealed sugar binding subsites, distant from the catalytic residues, which have been proposed to be involved in the cyclodextrin size specificity of these enzymes. to probe the importance of ...200010686101
catabolic pathways of glucose in bacillus circulans var. alkalophilus.enzymes and the metabolic pathways of glucose catabolism of bacillus circulans var. alkalophilus were studied. the metabolism of the microbe was mixed acid fermentative yielding mainly acetic and formic acids as end products from glucose. it was estimated that b. circulans var. alkalophilus partitions 90%-93% of the carbon from glucose into the embden-meyerhof-parnas (emp) pathway and 7%-10% into the hexose monophosphate (hmp) and entner-doudoroff (ed) pathways. rather low activities of glucose ...199910591018
facile enzymatic conversion of lactose into lacto-n-tetraose and lacto-n-neotetraose.lacto-n-tetraose (galbeta1 -3glcnacbeta1-3galbeta1-4glc, lnt) and lacto-n-neotetraose (galbeta1-4glcnacbeta1-3galbeta1-4glc, lnnt) were enzymatically synthesized by consecutive additions of glcnac and gal residues to lactose. lacto-n-triose ii (glcnacbeta1-3galbeta1-4glc) was prepared first by the transfer of glcnac from udp-glcnac to lactose by beta-1,3-n-acetylglucosaminyltransferase from bovine serum. the resulting lacto-n-triose ii was converted into lnt and lnnt utilizing two kinds of beta- ...199910596893
prosthetic heart valve endocarditis caused by bacillus circulans.we report a case of prosthetic valve endocarditis due to bacillus circulans in a 56-year-old woman. pre-operative blood cultures were negative and the organism was only recovered on culture of the explanted mechanical valve. we discuss the reasons for the late clinical presentation of this case, 15 months post valve replacement, caused by an organism which is conventionally regarded as 'early' pathogen. the patient recovered well post surgery on a 6 week course of trimethoprim and ciprofloxacin.199910609537
effect of temperature and enzyme origin on the enzymatic synthesis of oligosaccharides.the aim of this research is to quantify the effect of temperature and enzyme origin on the enzymatic synthesis of oligosaccharides. quantification of these effects is important because temperature and enzyme origin are important process parameters. a kinetic model was used to describe the concentrations in time. the kinetic parameters were determined by using data obtained in batch experiments at various temperatures (20, 30, 40, and 50 degrees c) and by using beta-galactosidases from bacillus c ...200010689088
[biosynthesis of extracellular guanyl-specific ribonuclease from bacillus circulans].biosynthesis of extracellular alkaline guanyl-specific rnase by bacillus circulans (rnase bci) was studied. synthesis of the enzyme by the culture started in the late exponential phase and was inhibited by inorganic phosphate and glucose, in contrast to the biosynthesis of its structural and functional homologue, rnase ba (barnase) of b. amyloliquefaciens. it is suggested that differences in the regulation of the biosynthesis of rnase bci and ba are related to different structures of their gene ...19989891294
molecular directionality of beta-chitin biosynthesis.the molecular packing in beta-chitin unit cells was experimentally determined by a combination of unidirectional degradation by bacillus circulans chitinase a1 and microdiffraction electron crystallography using highly crystalline beta-chitin microfibrils from the protective tubes secreted by lamellibrachia satsuma. the mode of chain packing was found to be identical with that of the previously published crystal model for beta-chitin, despite a controversial definition of the unit cell parameter ...19999931263
butirosin-biosynthetic gene cluster from bacillus circulans.butirosin is an interesting 2-deoxystreptamine (dos)-containing aminoglycoside antibiotic produced by non-actinomycete bacilli. recently we were successful in purification of 2-deoxy-scyllo-inosose synthase from butirosin-producer bacillus circulans as the key enzyme for the biosynthesis of dos, in cloning of the responsible gene (btrc), and in its overexpression in escherichia coli. the present study involved gene-walking approach, which allowed us to find a gene cluster around btrc. the functi ...200011132962
bacillus siralis sp. nov., a novel species from silage with a higher order structural attribute in the 16s rrna genes.a novel bacterial strain (171544t) was recently isolated from silage and was classified in the genus bacillus by 16s rdna sequence analysis. additional silage samples have been investigated in the present study and four organisms resembling strain 171544t were isolated. phenotypic and genotypic characterization of these bacteria showed that they constitute a new species of the genus bacillus. this taxon was positioned in the family bacillaceae on the basis of evolutionary distance trees using 16 ...200011155995
cloning, sequences, and characterization of two chitinase genes from the antarctic arthrobacter sp. strain tad20: isolation and partial characterization of the enzymes.arthrobacter sp. strain tad20, a chitinolytic gram-positive organism, was isolated from the sea bottom along the antarctic ice shell. arthrobacter sp. strain tad20 secretes two major chitinases, chia and chib (archia and archib), in response to chitin induction. a single chromosomal dna fragment containing the genes coding for both chitinases was cloned in escherichia coli. dna sequencing analysis of this fragment revealed two contiguous open reading frames coding for the precursors of archia (8 ...200111160110
the three transglycosylation reactions catalyzed by cyclodextrin glycosyltransferase from bacillus circulans (strain 251) proceed via different kinetic mechanisms.cyclodextrin glycosyltransferase (cgtase) catalyzes three transglycosylation reactions via a double displacement mechanism involving a covalent enzyme-intermediate complex (substituted-enzyme intermediate). characterization of the three transglycosylation reactions, however, revealed that they differ in their kinetic mechanisms. disproportionation (cleavage of an alpha-glycosidic bond of a linear malto-oligosaccharide and transfer of one part to an acceptor substrate) proceeds according to a pin ...200010651801
chitosanase activity of the enzyme previously reported as beta-1,3-1,4-glucanase from bacillus circulans wl-12.chitosanases 33 kda and 40 kda in size were detected in the culture supernatant of bacillus circulans wl-12. one of the two chitosanases, chitosanse 40 (40-kda chitosanase) has been shown to be identical to the enzyme which has been reported previously as a beta-1,3-1,4-glucanase by bueno et al. the enzyme has been classified into family 8 glycosyl hydrolases together with the enzymes formally known as cellulase family d. this enzyme named chitosanase 40/beta-1,3-1,4-glucanase hydrolyzed both ch ...19989972232
sugar ring distortion in the glycosyl-enzyme intermediate of a family g/11 xylanase.the 1.8 a resolution structure of the glycosyl-enzyme intermediate formed on the retaining beta-1,4-xylanase from bacillus circulans has been determined using x-ray crystallographic techniques. the 2-fluoro-xylose residue bound in the -1 subsite adopts a 2,5b (boat) conformation, allowing atoms c5, o5, c1, and c2 of the sugar to achieve coplanarity as required at the oxocarbenium ion-like transition states of the double-displacement catalytic mechanism. comparison of this structure to that of a ...199910220321
analysis of the dynamic properties of bacillus circulans xylanase upon formation of a covalent glycosyl-enzyme intermediate.nmr spectroscopy was used to search for mechanistically significant differences in the local mobility of the main-chain amides of bacillus circulans xylanase (bcx) in its native and catalytically competent covalent glycosyl-enzyme intermediate states. 15n t1, t2, and 15n[1h] noe values were measured for approximately 120 out of 178 peptide groups in both the apo form of the protein and in bcx covalently modified at position glu78 with a mechanism-based 2-deoxy-2-fluoro-beta-xylobioside inactivat ...200010752613
trp122 and trp134 on the surface of the catalytic domain are essential for crystalline chitin hydrolysis by bacillus circulans chitinase a1.from the 3d-structural analysis of the catalytic domain of chitinase a1, two exposed tryptophan residues (w122 and w134) are proposed to play an important role in guiding a chitin chain into the catalytic cleft during the crystalline chitin hydrolysis. mutation of either w122 or w134 to alanine significantly reduced the hydrolyzing activity against highly crystalline beta-chitin microfibrils. double mutation almost completely abolished the hydrolyzing activity. on the other hand, the hydrolyzing ...200111297738
modelling and parameter estimation of the enzymatic synthesis of oligosaccharides by beta-galactosidase from bacillus circulansthe aim of this research is to develop a model to describe oligosaccharide synthesis and simultaneously lactose hydrolysis. model a (engineering approach) and model b (biochemical approach) were used to describe the data obtained in batch experiments with beta-galactosidase from bacillus circulans at various initial lactose concentrations (from 0.19 to 0.59 mol.kg(-1)). a procedure was developed to fit the model parameters and to select the most suitable model. the procedure can also be used for ...199910404236
solution structure of the chitin-binding domain of bacillus circulans wl-12 chitinase a1.the three-dimensional structure of the chitin-binding domain (chbd) of chitinase a1 (chia1) from a gram-positive bacterium, bacillus circulans wl-12, was determined by means of multidimensional heteronuclear nmr methods. chia1 is a glycosidase that hydrolyzes chitin and is composed of an n-terminal catalytic domain, two fibronectin type iii-like domains, and c-terminal chbd(chia1) (45 residues, ala(655)-gln(699)), which binds specifically to insoluble chitin. chbd(chia1) has a compact and globul ...200010788483
molecular cloning of the gene for the key carbocycle-forming enzyme in the biosynthesis of 2-deoxystreptamine-containing aminocyclitol antibiotics and its comparison with dehydroquinate synthase.the 2-deoxystreptamine aglycon is a common structural feature found in aminocyclitol antibiotics including neomycin, kanamycin, tobramycin, gentamicin, sisomicin, butirosin and ribostamycin. a key enzyme involved in the biosynthesis of the 2-deoxystreptamine moiety is 2-deoxy-scyllo-inosose (doi) synthase which catalyses the carbocycle formation from d-glucose-6-phosphate to 2-deoxy-scyllo-inosose. the recent success of isolating the 2-deoxy-scyllo-inosose synthase from bacillus circulans prompt ...199910470681
crystal structure of chitosanase from bacillus circulans mh-k1 at 1.6-a resolution and its substrate recognition mechanism.chitosanase from bacillus circulans mh-k1 is a 29-kda extracellular protein composed of 259 amino acids. the crystal structure of chitosanase from b. circulans mh-k1 has been determined by multiwavelength anomalous diffraction method and refined to crystallographic r = 19.2% (r(free) = 23.5%) for the diffraction data at 1.6-a resolution collected by synchrotron radiation. the enzyme has two globular upper and lower domains, which generate the active site cleft for the substrate binding. the over ...199910521473
regioselective synthesis of p-nitrophenyl glycosides of beta-d-galactopyranosyl-disaccharides by transglycosylation with beta-d-galactosidases.the beta-d-galactosidase from porcine liver induced regiospecific transglycosylation of beta-d-galactose from beta-d-gal-oc6h4no2-o to oh-6 of, respectively, p-nitrophenyl glycoside acceptors of gal, glcnac and galnac to afford beta-gal-(1-->6)-alpha-gal-oc6h4no2-p, beta-gal-(1--> 6)-beta-gal-oc6h4no2-p, beta-gal-(1-->6)-alpha-galnac-oc6h4no2-p, beta-gal-(1-->6)-beta-galnac-oc6h4no2-p, beta-gal-(1-->6)-alpha-glcnac-oc6h4no2-p, and beta-gal-(1-->6)-beta-glcnac-oc6h4no2-p. the enzyme showed much h ...200010795819
characterization of a salt-tolerant family 42 beta-galactosidase from a psychrophilic antarctic planococcus isolate.we isolated a gram-positive, halotolerant psychrophile from a hypersaline pond located on the mcmurdo ice shelf in antarctica. a phylogenetic analysis of the 16s rrna gene sequence of this organism showed that it is a member of the genus planococcus. this assignment is consistent with the morphology and physiological characteristics of the organism. a gene encoding a beta-galactosidase in this isolate was cloned in an escherichia coli host. sequence analysis of this gene placed it in glycosidase ...200010831422
cleavage and purification of intein fusion proteins using the streptococcus gordonii spex system.a gram-positive bacterial expression vector using streptococcus gordonii has been developed for expression and secretion, or surface anchoring of heterologous proteins. this system, termed surface protein expression system or spex, has been used to express a variety of surface anchored and secreted proteins. in this study, the mycobacterium xenopi (mxe) gyra intein and chitin binding domain from bacillus circulans chitinase al were used in conjunction with spex to express a fusion protein to fac ...200111513092
the role of arginine 47 in the cyclization and coupling reactions of cyclodextrin glycosyltransferase from bacillus circulans strain 251 implications for product inhibition and product specificity.cyclodextrin glycosyltransferase (cgtase) (ec 2.4.1.19) is used for the industrial production of cyclodextrins. its application, however, is hampered by the limited cyclodextrin product specificity and the strong inhibitory effect of cyclodextrins on cgtase activity. recent structural studies have identified arg47 in the bacillus circulans strain 251 cgtase as an active-site residue interacting with cyclodextrins, but not with linear oligosaccharides. arg47 thus may specifically affect cgtase re ...200010848958
kinetic analysis of the reaction catalyzed by chitinase a1 from bacillus circulans wl-12 toward the novel substrates, partially n-deacetylated 4-methylumbelliferyl chitobiosides.the kinetic behavior of chitinase a1 from bacillus circulans wl-12 was investigated using the novel fluorogenic substrates, n-deacetylated 4-methylumbelliferyl chitobiosides [glcn-glcnac-umb (2), glcnac-glcn-umb (3), and (glcn)(2)-umb (4)], and the results were compared with those obtained using 4-methylumbelliferyl n, n'-diacetylchitobiose [(glcnac)(2)-umb (1)] as the substrate. the chitinase did not release the umb moiety from compound 4, but successfully released umb from the other substrates ...200010913612
identification of bacteria in pasteurized zucchini purées stored at different temperatures and comparison with those found in other pasteurized vegetable purées.one hundred nineteen isolates from a commercial zucchini purée stored at 4, 10, and 20 to 25 degrees c were fingerprinted using repetitive sequence-based pcr (rep-pcr) and classified into 35 rep types. one representative isolate of each rep type was subsequently identified by api50chb/20e profile and partial rrs gene sequence analysis. nine rep types were misidentified by the api system. strains were misidentified as being in the bacillus circulans (group 2) api taxon or in taxa with a low numbe ...200111571151
molecular cloning of a chitinase gene from bacillus circulans c-2.the 2-10 kb dna fragments of the psti partially digested total dna of bacillus circulans c-2 were cloned into the psti site of vector puc19 and the resulting hybrid dna molecules were then transformed into escherichia coli. one chitinase gene-containing clone (named pcht1) was selected from about 8000 recombinants on chitin overlay plates. analysis of pcht1 cut with 12 restriction enzymes showed that the inserted fragment in this clone was about 3.0 kb in size and contained one site for each of ...19989759542
detailed structural analysis of glycosidase/inhibitor interactions: complexes of cex from cellulomonas fimi with xylobiose-derived aza-sugars.detailed insights into the mode of binding of a series of tight-binding aza-sugar glycosidase inhibitors of two fundamentally different classes are described through x-ray crystallographic studies of complexes with the retaining family 10 xylanase cex from cellulomonas fimi. complexes with xylobiose-derived aza-sugar inhibitors of the substituted "amidine" class (xylobio-imidazole, k(i) = 150 nm; xylobio-lactam oxime, k(i) = 370 nm) reveal lateral interaction of the "glycosidic" nitrogen with th ...200010995222
bacterial phage receptors, versatile tools for display of polypeptides on the cell surface.four outer membrane proteins of escherichia coli were examined for their capabilities and limitations in displaying heterologous peptide inserts on the bacterial cell surface. the t7 tag or multiple copies of the myc epitope were inserted into loops 4 and 5 of the ferrichrome and phage t5 receptor fhua. fluorescence-activated cell sorting analysis showed that peptides of up to 250 amino acids were efficiently displayed on the surface of e. coli as inserts within fhua. strains expressing fhua fus ...200111698382
purification and characterization of a thermostable esterase from the moderate thermophile bacillus circulans.the thermostable esterase from the moderate thermophile bacillus circulans was purified to homogeneity using a four-step procedure. esterase activity was associated with a protein of molecular mass 95 kda, composed of three identical subunits of 30 kda. the esterase activity was thermostable with a maximum activity at 55 degrees c using initial rate assay. the half-inactivation temperature was 71 degrees c after a 1-h treatment, which compared favorably to that of other enzymes. activity at temp ...200010968629
characterization of pseudomonas aeruginosa chitinase, a gradually secreted protein.the gram-negative bacterium pseudomonas aeruginosa secretes many proteins into its extracellular environment via the type i, ii, and iii secretion systems. in this study, a gene, chic, coding for an extracellular chitinolytic enzyme, was identified. the chic gene encodes a polypeptide of 483 amino acid residues, without a typical n-terminal signal sequence. nevertheless, an n-terminal segment of 11 residues was found to be cleaved off in the secreted protein. the protein shows sequence similarit ...200111717261
linkage of sugar chains to a fragment peptide of fgf-5s by a chemoenzymatic strategy and changes in the rate of proteolytic hydrolysis.various o-linked and n-linked sugar chains were linked enzymatically to a fragment peptide (leu-ser-gln(or asn)-val-his-arg) of fgf-5s. first, galactose was linked with beta-(1-->3)-linkage to galnac-linked peptide by a transglycosylation using beta-galactosidase from bacillus circulans (recombinant). then sialic acid was linked with the aid of sialyltransferase from rat liver (recombinant) to give neuacalpha-(2-->3)-galbeta-(1-->3)-galnac-linked hexapeptide. further, a sialylated 2-chain biante ...200111788798
hydrolysis of beta-galactosyl ester linkage by beta-galactosidases.p-hydroxybenzoyl beta-galactose (phb-gal) was synthesized chemically to examine the hydrolytic activity of beta-galactosyl ester linkage by beta-galactosidases. the enzyme from penicillium multicolor hydrolyzed the substrate as fast as p-nitrophenyl beta-galactoside (pnp-gal), a usual substrate with a beta-galactosidic linkage. the enzymes from escherichia coli and aspergillus oryzae hydrolyzed phb-gal with almost the same rates as pnp-gal. the enzymes from bacillus circulans, saccharomyces frag ...200010993159
efficient synthesis of a sialyl t-antigen-linked glycopeptide by the chemoenzymatic method.a sialyl t-antigen-linked tetrapeptide was prepared by the combined method of chemical synthesis and enzymatic synthesis. the galnac-linked peptide was first obtained by using a commercial peptide synthesizer, and then a galactose residue was attached with beta-(1-->3)-linkage by transglycosylating with a recombinant beta-galactosidase from bacillus circulans. the sialic acid residue was then combined by alpha-(2-->3)-linkage with sialytransferase from rat liver.200010993167
molecular cloning and characterization of a chitosanase from the chitosanolytic bacterium burkholderia gladioli strain chb101.a chitosanase was purified from the culture fluid of the chitino- and chitosanolytic bacterium burkholderia gladioli strain chb101. the purified enzyme (chitosanase a) had a molecular mass of 28 kda, and catalyzed the endo-type cleavage of chitosans having a low degree of acetylation (0-30%). the enzyme hydrolyzed glucosamine oligomers larger than a pentamer, but did not exhibit any activity toward n-acetylglucosamine oligomers and colloidal chitin. the gene coding for chitosanase a (csna) was i ...200011030572
comparative study of the reaction mechanism of family 18 chitinases from plants and microbes.hydrolytic mechanisms of family 18 chitinases from rice (oryza sativa l.) and bacillus circulans wl-12 were comparatively studied by a combination of hplc analysis of the reaction products and theoretical calculation of reaction time-courses. all of the enzymes tested produced beta-anomers from chitin hexasaccharide [(glcnac)(6)], indicating that they catalyze the hydrolysis through a retaining mechanism. the rice chitinases hydrolyzed predominantly the fourth and fifth glycosidic linkages from ...200211926993
paenibacillus graminis sp. nov. and paenibacillus odorifer sp. nov., isolated from plant roots, soil and food.sixteen gram-positive endospore-forming bacteria previously isolated from soil, plant rhizospheres, plant roots and pasteurized pureed vegetables were studied to determine their taxonomic positions. the isolates were formerly identified as bacillus circulans based on their biochemical characters using api galleries. two of these strains, rsa19t and tod45t, were recently assigned to the genus paenibacillus based on phylogenetic analysis of their 16s rrna (rrs) gene sequence. in the present work, ...200211931174
trans-sialidase catalyzed sialylation of beta-galactosyldisaccharide with an introduction of beta-galactosidase.introduction of beta-galactosidase into a trans-sialidase reaction, i.e. sialic acid transfer reaction from a donor substrate (alpha2,3-sialyllactose) to an acceptor substrate (beta-galactosyldisaccharide), could improve the yield of desired sialylated trisaccharide by hydrolyzing lactose, a byproduct from the donor. when trans-sialidase reaction was performed with stoichiometric amounts (2 mm) of alpha2,3-sialyllactose and galbeta(1,3)glcnac, the yield of neuacalpha(2,3)galbeta(1,3)glcnac incre ...200111166807
an isolate of bacillus circulans toxic to mosquito larvae.a new strain of bacillus circulans isolated from a larva of culex quinquefasciatus showed larvicidal activity on 3 mosquitoes of medical importance. compared to bacillus sphaericus strain 2362, this b. circulans isolate proved less toxic to cx. quinquefasciatus and anopheles gambiae but was 107 times more toxic to aedes aegypti. moreover, in comparison to other studies, b. circulans was at least as pathogenic as b. thuringiensis var. israelensis in ae. aegypti. the tests have showed that the tox ...200211998934
protein profile and biochemical properties of bacillus circulans isolated from intestines of small free-living animals in poland.forty-seven strains of bacillus circulans isolated from the intestinal tract of free-living small mammals from the narvia and biebrza national park (ne poland) were compared with the electrophoretic whole-cell protein patterns on the basis of sds-page and biochemical characteristic using api tests (50 chb and 20e). the strains were grouped into two clusters (i and ii) at the similarity of protein pattern of 78% using the simple matching coefficient and clustering on unweighted pair group arithme ...200111501407
enterotoxin production in natural isolates of bacillaceae outside the bacillus cereus group.thirty-nine bacillus strains obtained from a variety of environmental and food sources were screened by pcr for the presence of five gene targets (hblc, hbld, hbla, nhea, and nheb) in two enterotoxin operons (hbl and nhe) traditionally harbored by bacillus cereus. seven isolates exhibited a positive signal for at least three of the five possible targets, including bacillus amyloliquefaciens, b. cereus, bacillus circulans, bacillus lentimorbis, bacillus pasteurii, and bacillus thuringiensis subsp ...200212039781
purification and characterization of heparinase that degrades both heparin and heparan sulfate from bacillus circulans.a heparinase that degrades both heparin and heparan sulfate (hs) was purified to homogeneity from the cell-free extract of bacillus circulans hpt298. the purified enzyme had a single band on sds-polyacrylamide gel electrophoresis with an estimated molecular mass of 111,000. the enzyme showed optimal activity at ph 7.5 and 45 degrees c, and its activity was stimulated in the presence of 5 mm cacl2, bacl2, or mgcl2. analysis of substrate specificity and degraded disaccharides demonstrated that the ...200212092842
gene cloning and biochemical analysis of thermostable chitosanase (tch-2) from bacillus coagulans ck108.the dna sequence of the thermostable chitosanase tch-2 gene from bacillus coagulans ck108 showed a 843-bp open reading frame that encodes a protein of 280 amino acids with a signal peptide corresponding to 32 kda in size. the deduced amino acid sequence of the chitosanase from bacillus coagulans ck108 has 61.6%, 48.0%, and 12.6% identities to those from bacillus ehemensis, bacillus circulans, and bacillus subtilis, respectively. c-terminal homology analysis shows that the enzyme belongs to the c ...200212092850
chromium (vi) biosorption and bioaccumulation by chromate resistant bacteria.in this study, strains that are capable of bioaccumulating cr(vi) were isolated from treated tannery effluent of a common effluent treatment plant. the cr(vi) concentration in this treated effluent was 0.96 mg/l, much above the statutory limit of 0.1 mg/l for discharge of industrial effluents into inland surface waters in india. in addition to the bioaccumulation, biosorption capabilities of living and dead cells were analysed. two strains, identified as bacillus circulans and bacillus megateriu ...200212152745
hydrogen bonding and catalysis: a novel explanation for how a single amino acid substitution can change the ph optimum of a glycosidase.the ph optima of family 11 xylanases are well correlated with the nature of the residue adjacent to the acid/base catalyst. in xylanases that function optimally under acidic conditions, this residue is aspartic acid, whereas it is asparagine in those that function under more alkaline conditions. previous studies of wild-type (wt) bacillus circulans xylanase (bcx), with an asparagine residue at position 35, demonstrated that its ph-dependent activity follows the ionization states of the nucleophi ...200010860737
the aman6 gene encoding a yeast mannan backbone degrading 1,6-alpha-d-mannanase in bacillus circulans: cloning, sequence analysis, and expression.a gene (aman6) encoding endo-1,6-alpha-d-mannanase, a yeast mannan backbone degrading enzyme from bacillus circulans was cloned. the putative aman6 was 1,767 base pairs long and encoded a mature 1,6-alpha-d-mannanase protein of 589 amino acids and a signal peptide of 36 amino acids. the purified mature 1,6-alpha-d-mannanase from the escherichia coli transformant showed 61-kda protein, and n-terminal amino acid sequence and other general properties of the recombinant enzyme were identical to thos ...200011055417
purification and characterization of a bacillus cereus exochitinase.five extracellular chitinases of bacillus cereus 6e1 were detected by a novel in-gel chitinase assay using carboxymethyl-chitin-remazol brilliant violet 5r (cm-chitin-rbv) as a substrate. the major chitinase activity was associated with a 36-kda (chi36) gel band. chi36 was purified by a one-step, native gel purification procedure derived from the new in-gel chitinase assay. the purified chi36 has optimal activity at ph 5.8 and retains some enzymatic activity between ph 2.5-8. the temperature opt ...200111267643
synthesis of nucleotide-activated oligosaccharides by beta-galactosidase from bacillus circulans.the enzymatic access to nucleotide-activated oligosaccharides by a glycosidase-catalyzed transglycosylation reaction was explored. the nucleotide sugars udp-glcnac and udp-glc were tested as acceptor substrates for beta-galactosidase from bacillus circulans using lactose as donor substrate. the udp-disaccharides gal(beta1-4)glcnac(alpha1-udp) (udp-lacnac) and gal(beta1-4)glc(alpha1-udp) (udp-lac) and the udp-trisaccharides gal(beta1-4)gal(beta1-4)glcnac(alpha1-udp and gal(beta1-4)gal(beta1-4)glc ...200111308028
bacillus circulans endophthalmitis.an 80-year-old woman presented with right endophthalmitis, characterized by chalky white deposits covering her posterior capsule. this occurred 17 months after uncomplicated right cataract surgery. a three-port pars plana vitrectomy and partial posterior capsulectomy isolated bacillus circulans, and the patient made a rapid and full recovery on topical cephalothin and prednisolone acetate 1%. the case demonstrates that, unlike endophthalmitis due to other bacillus spp., b. circulans endophthalmi ...200111341454
truncated aspartate aminotransferase from alkalophilic bacillus circulans with deletion of n-terminal 32 amino acids is a non-functional monomer in a partially structured state.aspartate aminotransferase (aspat) from alkalophilic bacillus circulans contains an additional n-terminal sequence of 32 amino acid residues that are absent in all other aspats from different sources. modeling suggested that this sequence forms two alpha-helical segments which establish a continuous network of interactions on the surface of the molecule. in the present study, we studied the role of the n-terminal sequence in folding and stability of aspat by applying the scanning calorimetry, an ...200111391020
hydrophobic amino acid residues in the acceptor binding site are main determinants for reaction mechanism and specificity of cyclodextrin-glycosyltransferase.cyclodextrin-glycosyltransferases (cgtases) (ec ) preferably catalyze transglycosylation reactions with glucosyl residues as acceptor, whereas the homologous alpha-amylases catalyze hydrolysis reactions using water as acceptor. this difference in reaction specificity is most likely caused by the acceptor binding site. to investigate this in detail we altered the acceptor site residues lys-232, phe-183, phe-259, and glu-264 of bacillus circulans strain 251 cgtase using site-directed mutagenesis. ...200111555657
use of a chia probe for detection of chitinase genes in bacteria from the chesapeake bay(1).pcr primers specific for the chia gene were designed by alignment and selection of highly conserved regions of chia sequences from serratia marcescens, alteromonas sp., bacillus circulans and aeromonas caviae. these primers were used to amplify a 225 bp fragment of the chia gene from vibrio harveyi to produce a chia gene probe. the chia pcr primers and probe were used to detect the presence of the chia gene in an assemblage of 53 reference strains and gave consistent results. selected chia fragm ...200011053737
addition of polar organic solvents can improve the product selectivity of cyclodextrin glycosyltransferase. solvent effects on cgtase.cyclodextrin glycosyltransferase (ec 2.4.1.19, cgtase) is an enzyme that produces cyclodextrins from starch via an intramolecular transglycosylation reaction. addition of small amounts (10% v/v) of polar organic solvents can affect both the overall production yield and the type of cyclodextrin produced from a maltodextrin substrate under simulated industrial process conditions. using cgtase from thermoanaerobacter sp. all solvents produced an increase in cyclodextrin yield when compared with a c ...200011064053
intein-mediated rapid purification of cre recombinase.cre recombinase produced by bacteriophage p1 catalyzes site-specific recombination of dna between loxp recognition sites in both prokaryotic and eukaryotic cells and has been widely used for genome engineering and in vitro cloning. recombinant cre has been overproduced in escherichia coli and its purification involves multiple steps. in this report, we used an "intein" fusion system to express cre as a c-terminal fusion to a modified protein splicing element, i.e., intein. the modified intein co ...200111388811
[sequencing of a beta-amylase gene from bacillus firmus].the gene encoding a beta-amylase from bacillus firmus 725 was sequenced. the sequenced dna of 2012 bp contains one open reading frame of 1406 nucleotides without a translation stop codon. the deduced amino acid sequence homology with those known bacterial and some plant beta-amylase was 98% for bacillus polymyxa 72, 98% for bacillus polymyxa atcc8523, 82% for bacillus circulans, 54% for clostridium thermosulfurogenes, 49% for bacillus cereus bq10-s1, 50% for bacillus cereus var. mycoides, 36% fo ...199812549376
effect of fusaric acid and phytoanticipins on growth of rhizobacteria and fusarium oxysporum.suppression of soilborne diseases by biocontrol agents involves complex interactions among biocontrol agents and the pathogen and between these microorganisms and the plant. in general, these interactions are not well characterized. in this work, we studied (i) the diversity among strains of fluorescent pseudomonas spp., bacillus spp., and paenibacillus sp. for their sensitivity to fusaric acid (fac) and phytoanticipins from different host plants, (ii) the diversity of pathogenic and nonpathogen ...200212556125
solution structure of the fibronectin type iii domain from bacillus circulans wl-12 chitinase a1.growing evidence suggests that horizontal gene transfer plays an integral role in the evolution of bacterial genomes. one of the debated examples of horizontal gene transfer from animal to prokaryote is the fibronectin type iii domain (fniiid). certain extracellular proteins of soil bacteria contain an unusual cluster of fniiids, which show sequence similarity to those of animals and are likely to have been acquired horizontally from animals. here we report the solution structure of the fniiid o ...200211600504
evidence for the production of chemical compounds analogous to nod factor by the silicate bacterium bacillus circulans gy92.silicate bacteria are generally placed in the species bacillus circulans and are widely used in biological fertilisers and biological leaching. the bacteria can form conspicuous amounts of extracellular polysaccharides in nitrogen-free media or in the presence of substrates with large c/n ratios. using high performance liquid chromatography, we have shown that b. circulans produced a new peak/compound when induced with the plant-to-bacteria signal molecule genistein. this material co-eluted with ...200111716218
high efficient expression in escherichia coli of chitinase gene cloned from bacillus circulans c-2.subcloning analysis of a cloned dna fragment from bacillus circulans containing the chitinase gene chi1 showed that the chitinase gene lies on a 1.7kb psti-styi fragment. the chitinase gene could be expressed in escherichia coli strains jm107, dh5alpha, xl1-blue and tg-1 with various efficiencies. the expression level of chitinase gene was highest in jm107, which was almost the same as that in b. circulans c-2. the molecular weight of extracellular chitinase was 66 kd by sds-page analysis. cell ...199812168036
cloning and structural analysis of bglm gene coding for the fungal cell wall-lytic beta-1,3-glucan-hydrolase bglm of bacillus circulans iam1165.bacillus circulans iam1165 produces isoforms of beta-1,3-glucan-hydrolases. of these enzymes, the 42-kda enzyme bgim degrades aspergillus oryzae cell walls the most actively. a gene coding for a bgim precursor consisting of 411 amino acid residues was cloned. the 27 n-terminal amino acid sequence of the precursor is a signal peptide. the 141 c-terminal amino acid sequence showed a motif of carbohydrate-binding module family 13. this domain bound to pachyman, lichenan, and a. oryzae cell walls. t ...200212162545
dissecting the electrostatic interactions and ph-dependent activity of a family 11 glycosidase.previous studies of the low molecular mass family 11 xylanase from bacillus circulans show that the ionization state of the nucleophile (glu78, pk(a) 4.6) and the acid/base catalyst (glu172, pk(a) 6.7) gives rise to its ph-dependent activity profile. inspection of the crystal structure of bcx reveals that glu78 and glu172 are in very similar environments and are surrounded by several chemically equivalent and highly conserved active site residues. hence, there are no obvious reasons why their ap ...200111513590
phylogenetic relationships between bacillus species and related genera inferred from comparison of 3' end 16s rdna and 5' end 16s-23s its nucleotide sequences.the nucleotide sequences of the 3' end of the 16s rdna and the 16s-23s internal transcribed spacer (its) of 40 bacillaceae species were determined. these included 21 bacillus, 9 paenibacillus, 6 brevibacillus, 2 geobacillus, 1 marinibacillus and 1 virgibacillus species. comparative sequence analysis of a 220 bp region covering a highly conserved 150 bp sequence located at the 3' end of the 16s rrna coding region and a conserved 70 bp sequence located at the 5' end of the 16s-23s its of the 40 sp ...200312807189
the remote substrate binding subsite -6 in cyclodextrin-glycosyltransferase controls the transferase activity of the enzyme via an induced-fit mechanism.cyclodextrin-glycosyltransferase (cgtase) catalyzes the formation of alpha-, beta-, and gamma-cyclodextrins (cyclic alpha-(1,4)-linked oligosaccharides of 6, 7, or 8 glucose residues, respectively) from starch. nine substrate binding subsites were observed in an x-ray structure of the cgtase from bacillus circulans strain 251 complexed with a maltononaose substrate. subsite -6 is conserved in cgtases, suggesting its importance for the reactions catalyzed by the enzyme. to investigate this in det ...200211696539
identification of l-glutamine: 2-deoxy-scyllo-inosose aminotransferase required for the biosynthesis of butirosin in bacillus circulans.using inverse pcr, two new genes (btrn and btrs) were identified upstream of the putative glycosyltransferase gene btrm in the butirosin-biosynthetic btr gene cluster of bacillus circulans. the upstream gene btrs showed significant homology with stsc of streptomyces griseus, which encodes l-glutamine:scyllo-inosose aminotransferase in the biosynthesis of streptomycin. the function of btrs was further confirmed by heterologous expression in escherichia coli and chemical identification of the conv ...200212374384
microbial starch-binding domains as a tool for targeting proteins to granules during starch biosynthesis.modification of starch biosynthesis pathways holds an enormous potential for tailoring granules or polymers with new functionalities. in this study, we explored the possibility of engineering artificial granule-bound proteins, which can be incorporated in the granule during biosynthesis. the starch-binding domain (sbd)-encoding region of cyclodextrin glycosyltransferase from bacillus circulans was fused to the sequence encoding the transit peptide (amyloplast entry) of potato granule-bound starc ...200312678563
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