Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| 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 ... | 2000 | 10848958 |
| 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 ... | 2000 | 10831422 |
| galactosylation of thiol group by beta-galactosidase. | beta-galactosidase catalyzed beta-galactosylation not only of a hydroxyl group but also of a thiol group in the condensation reaction of d-galactose and 2-mercaptoethanol. the thio-galactosylation product was confirmed as 2-hydroxyethyl s-beta-d-galactoside on the bases of fast atom bombardment mass spectrometry, infrared spectroscopy, and nuclear magnetic resonance spectorometry. aspergillus oryzae beta-galactosidase hydrolyzed p-nitrophenyl s-beta-d-galactoside most rapidly among several beta- ... | 2000 | 10830485 |
| 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 ... | 2000 | 10809681 |
| molecular analysis of maleate cis-trans isomerase from thermophilic bacteria. | several strains of thermophilic bacteria containing maleate cis-trans isomerase were isolated from soil samples and identified as bacillus stearothermophilus, bacillus circulans, bacillus brevis, and deleya halophila. the maleate cis-trans isomerase was purified and characterized from one of the isolated strains, b. stearothermophilus mi-102. the purified enzyme of strain mi-102 showed higher thermal stability than the enzyme of a mesophile, alcaligenes faecalis ifo13111. the seven maleate cis-t ... | 2000 | 10803955 |
| 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 ... | 2000 | 10795819 |
| 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 ... | 2000 | 10788483 |
| 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 ... | 2000 | 10752613 |
| 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 ... | 2000 | 10689088 |
| 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 ... | 2000 | 10686101 |
| 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 ... | 2000 | 10675298 |
| 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 ... | 2000 | 10660543 |
| 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 ... | 2000 | 10651801 |
| 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. | 1999 | 10609537 |
| 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- ... | 1999 | 10596893 |
| 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 ... | 1999 | 10591018 |
| 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 ... | 1999 | 10583986 |
| 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 ... | 1999 | 10521473 |
| 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 ... | 1999 | 10470681 |
| 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 ... | 1999 | 10441726 |
| 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 ... | 1999 | 10425751 |
| modelling and parameter estimation of the enzymatic synthesis of oligosaccharides by beta-galactosidase from bacillus circulans | the 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 ... | 1999 | 10404236 |
| 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 |
| 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 ... | 1999 | 10344560 |
| 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 ... | 1999 | 10220321 |
| 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 ... | 1998 | 9972232 |
| 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 ... | 1999 | 9931263 |
| [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 ... | 1998 | 9891294 |
| 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 ... | 1998 | 9860832 |
| 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- ... | 1998 | 9805383 |
| 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 ... | 1998 | 9759542 |
| 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 ... | 1998 | 9753433 |
| 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) ... | 1998 | 9738929 |
| substrate binding to a cyclodextrin glycosyltransferase and mutations increasing the gamma-cyclodextrin production. | bacterial cyclodextrin glycosyltransferases use starch to produce cyclic maltooligosaccharides (cyclodextrins) which are of interest in various applications. the cyclization reaction gives rise to a spectrum of ring sizes consisting of predominantly six to eight glucosyl units. using the enzyme from bacillus circulans strain no. 8, binding studies have been performed with several substrates and analogues. the observed binding modes differ in detail, but agree in general with data on homologous e ... | 1998 | 9738912 |
| bacillus pseudomycoides sp. nov. | previous dna relatedness studies showed that strains identified as bacillus mycoides segregated into two genetically distinct yet phenotypically similar groups, one being b. mycoides sensu stricto and the other, an unclassified taxon. in the present study, the taxonomic position of this second group was assessed by measuring dna relatedness and determining phenotypic characteristics of an increased number of b. mycoides strains. also determined was the second group's 16s rna gene sequence. the 3 ... | 1998 | 9734060 |
| 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 ... | 1998 | 9687406 |
| 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 ... | 1998 | 9684886 |
| transfer reactions catalyzed by cyclodextrin glucosyltransferase using 4-thiomaltosyl and c-maltosyl fluorides as artificial donors. | cyclodextrin glycosyltransferase enzyme from bacillus circulans catalyzed the effective conversion of 4-thio-alpha-maltosyl fluoride into cyclo-alpha-(1-->4(2))-thiomalto -tetraoside, -pentaoside, -hexaoside and linear hemithiomaltooligosaccharides. however, under the same conditions, c-maltosyl fluoride afforded only linear modified maltotetraose, maltohexaose and maltooctaose in moderate yield. | 1997 | 9648273 |
| 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 ... | 1997 | 9648258 |
| 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 ... | 1998 | 9601025 |
| 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 ... | 1998 | 9571781 |
| 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 ... | 1998 | 9565691 |
| 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 ... | 1998 | 9557875 |
| 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 ... | 1998 | 9538235 |
| 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 ... | 1998 | 9532804 |
| application of the resident plasmid integration technique to construct a strain of streptococcus godronii able to express the bacillus circulans cycloisomaltooligosaccharide glucanotransferase gene, and secrete its active gene product. | a novel transformation technique, resident plasmid integration, for the cloning of foreign dna in oral streptococci was described recently (t. shiroza and h.k. kuramitsu, plasmid 34 (1995) 85-95. this technique is based on the integration of linearized foreign genes by recombination-proficient bacteria onto a resident plasmid, if an appropriate selection marker is flanked by the same anchor sites present in the resident plasmid. since the transforming vehicles for this system included a puc-deri ... | 1998 | 9511752 |
| 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 ... | 1998 | 9488711 |
| 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 ... | 1998 | 9485306 |
| 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 ... | 1997 | 9416621 |
| recombinant thermostable cycloinulo-oligosaccharide fructanotransferase produced by saccharomyces cerevisiae. | a truncated fragment of the cycloinulo-oligosaccharide fructanotransferase (cftase) gene of bacillus circulans mci-2554 was fused to the prepro secretion sequence of the alpha-factor and expressed in saccharomyces cerevisiae under the control of the 5' upstream region of the isocitrate lyase gene of candida tropicalis (upr-icl). efficiently secreted recombinant cftase protein (yeast cftase) was purified. yeast cftase consisted of three protein molecules, each of which had cftase activity (yeast ... | 1997 | 9406417 |
| mechanisms of radiation-induced gene responses. | while identifying genes differentially expressed in cells exposed to ultraviolet radiation, we identified a transcript with a 25-nucleotide region that is highly conserved among a variety of species, including bacillus circulans, pumpkin, yeast, drosophila, mouse, and man. in the 5' untranslated region of a gene, the sequence is predominantly in a +/+ orientation with respect to the coding dna strand; while in the coding region and the 3' untranslated region, the sequence is most frequently in a ... | 1997 | 9368283 |
| 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 ... | 1997 | 9335170 |
| bacterial killing ability of 10% ethylene oxide plus 90% hydrochlorofluorocarbon sterilizing gas. | to use a serum and salt challenge in narrow-lumen carriers to evaluate a 10% ethylene oxide plus 90% hydrochlorofluorocarbon (eo-hcfc) sterilant mixture in a retrofitted 12/88 sterilizer as an alternative to the banned chlorofluorocarbon-ethylene oxide (eo) sterilant mixture. | 1997 | 9309437 |
| cloning and characterization of the gene encoding a novel beta-galactosidase from bacillus circulans. | a novel beta-galactosidase (beta-gal) gene was cloned from bacillus circulans atcc 31382. the coding region was 1,758 bp and encoded a polypeptide of 586 amino acids with a deduced molecular mass of 66,888. active staining for beta-gal showed that b. circulans atcc 31382 produced three beta-gal isozymes. two of these were detected in biolacta n5 (daiwakasei co.), but the product of this novel gene corresponded to the one not contained in biolacta n5. the novel beta-gal showed the highest amino a ... | 1997 | 9301106 |
| 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 ... | 1997 | 9255974 |
| vancomycin-resistant bacillus circulans carrying the vana gene responsible for vancomycin resistance in enterococci. | 1997 | 9248754 | |
| 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 ... | 1997 | 9245426 |
| 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 ... | 1997 | 9224900 |
| 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 ... | 1997 | 9207913 |
| broviac catheter-related bacteraemias due to unusual pathogens in children with cancer: case reports with literature review. | among 102 episodes of intravenous catheter related bacteraemias documented between january 1989 and july 1996 in children receiving antineoplastic chemotherapy or bone marrow transplantation at g. gaslini children's hospital, genoa, italy, were identified seven episodes due to unusual pathogens: bacillus circulans, bacillus licheniformis, brevibacterium casei, flavimonas oryzihabitans, porphyromonas asaccharolytica, comamonas acidovorans and agrobacterium radiobacter. susceptibility to different ... | 1997 | 9200028 |
| evaluation of the cathetron system for recycling angioplasty catheters. | the cathetron (minntech corporation, minneapolis, mn) peracetic acid-based reprocessing method for percutaneous transluminal coronary angioplasty (ptca) catheters was evaluated for ability to sterilize and maintain catheter integrity. the balloons and lumens of 42 catheters (140 reprocessing cycles) were inoculated with suspensions of staphylococcus epidermidis, s. aureus, pseudomonas aeruginosa, and bacillus circulans. five catheters failed the initial evaluation of mechanical integrity and wer ... | 1997 | 9184282 |
| purification and characterization of the d-hydantoinase from bacillus circulans. | a d-hydantoinase (5,6-dihydropyrimidine amidohydrolase) was purified to homogeneity from bacillus circulans. purification of two hundred forty-three-fold was achieved with an overall yield of 12%. the relative molecular mass of the native enzyme is 212,000 and that of the subunit is 53,000. this enzyme is an acidic protein with an isoelectric point of 4.55. the enzyme is sensitive to thiol reagent and requires metal ions for its activity. the optimal conditions for the hydantoinase activity are ... | 1997 | 9170254 |
| characterization of a monoclonal antibody that specifically inhibits pullulanase activity of bacillus circulans amylase-pullulanase enzyme. | a monoclonal antibody (mab) against amylase pullulanase enzyme from bacillus circulans, which hydrolyzes not only the alpha-1,6-glycosidic linkage but also the alpha-1,4-glycosidic linkage to the same extent, has been produced by the fusion of balb/c mouse spleen cells immunized with the native enzyme and p3x63ag8u1 myeloma cells, and examined for inhibition of pullulanase activity in order to characterize the catalytic site of the pullulanase. the mab recognizes active enzyme, but not the sds-d ... | 1997 | 9170253 |
| emended description of paenibacillus amylolyticus and description of paenibacillus illinoisensis sp. nov. and paenibacillus chibensis sp. nov. | the taxonomic position of unidentified group 6 of bacillus circulans as described by nakamura and swezey (l.k. nakamura and j. swezey, int. j. syst. bacteriol. 33:46-52, 1983) was determined, and the taxonomy of paenibacillus amylolyticus was reexamined. the results of pcr amplification of a 16s rrna gene fragment with a specific primer and comparative analysis of 16s rrna gene sequences warranted placing the two taxa in the genus paenibacillus. the levels of dna reassociation among the strains ... | 1997 | 9103613 |
| structural study of an exocellular polysaccharide of bacillus circulans. | bacillus circulans, a soil bacterium, produced an exocellular polysaccharide of high viscosity. on the basis of the results of methylation analysis, mild acid hydrolysis, and 1d and 2d 1h-nmr spectroscopy, it was concluded that the polysaccharide has a basic repeating unit composed of beta-l-rhamnopyranose, alpha-d-mannopyranose, alpha-d-galactopyranose, and alpha-d-glucopyranuronic acid with the following structure. [symbol: see text] | 1997 | 9095555 |
| enzymatic syntheses of glcnac beta 1-2man and gal beta 1-4glcnac beta 1-2man as components of complex type sugar chains. | glcnac beta 1-2man and glcnac beta 1-6man were synthesized using the reverse hydrolysis activity of beta-n-acetylglucosaminidase from both jack beans and bacillus circulans. in turn, gal beta 1-4glcnac beta 1-2man and gal beta 1-4glcnac beta 1-6man were synthesized regioselectively using the transglycosylation activity of beta-galactosidase from diplococcus pneumoniae and b. circulans, respectively. these di- and trisaccharides are important components of complex type sugar chains and will be us ... | 1997 | 9076516 |
| purification, properties, and n-terminal amino acid sequences of guar gum-degrading enzyme from bacillus circulans k-1. | a guar gum-degrading enzyme of the newly isolated bacillus circulans k-1 was purified to an electrophoretically homogeneous state. the molecular weight of the purified enzyme was 62,000 by sds-page. the purified enzyme was separated into a least six isozymes by isoelectric focusing and the pi of these isozymes were 5.4, 5.5, 5.6, 5.8, 6.0, and 6.2, respectively. the n-terminal amino acid sequences of the typical three of these proteins were all the same, ala-ser-gly-phe-tyr-val-ser-gly-thr-lys-l ... | 1997 | 9058961 |
| positioning the acid/base catalyst in a glycosidase: studies with bacillus circulans xylanase. | the mechanism of action employed by a glycosidase is dictated, in part, by the distance between the two catalytic carboxylic acids. in the retaining endo-beta-1,4-xylanase from bacillus circulans, this critical distance (approximately 5.5 a) has been altered by mutagenesis of the putative acid/base catalyst glu172. an increase in the separation (glu172asp) resulted in a 400-fold decrease in the k(cat) value for xylan hydrolysis. by contrast, a decrease in the separation, achieved by the selectiv ... | 1997 | 9047328 |
| complete synthesis of 3'-sialyl-n-acetyllactosamine by regioselective transglycosylation. | transglycolytic synthesis of 3'-sialyl-n-acetyllactosamine by sequential use of beta-galactosidase from bacillus circulans and trans-sialidase from trypanosoma cruzi was described. these reactions depicted the first complete synthesis of a biologically important oligosaccharide with high regioselectivity avoiding use of glycosyltransferases and ndp sugars. | 1996 | 8985145 |
| expression of chitinase-encoding genes from aeromonas hydrophila and pseudomonas maltophilia in bacillus thuringiensis subsp. israelensis. | fifty isolates of chitinase (cts)-producing bacteria were collected from soil samples and tested for their ability to degrade chitin using colloidal chitin agar as the primary plating medium. the results indicated that three isolates could degrade chitin at high ph. further studies also demonstrated that crude cts preparations from bacillus circulans (bc) no. 4.1 could enhance the toxicity of bacillus thuringiensis subsp. kurstaki (bt-k) toward diamondback moth larvae. thus, it might be useful t ... | 1996 | 8955637 |
| the raw starch binding domain of cyclodextrin glycosyltransferase from bacillus circulans strain 251. | the e-domain of cyclodextrin glycosyltransferase (cgtase) (ec 2.4.1.19) from bacillus circulans strain 251 is a putative raw starch binding domain. analysis of the maltose-dependent cgtase crystal structure revealed that each enzyme molecule contained three maltose molecules, situated at contact points between protein molecules. two of these maltoses were bound to specific sites in the e-domain, the third maltose was bound at the c-domain. to delineate the roles in raw starch binding and cycliza ... | 1996 | 8955113 |
| convenient synthesis of beta-(1-->3)-galactosyl disaccharide alpha-glycoside and its analogs as mimic units of mucin-type carbohydrate. | beta-galactosidase from porcine testes induced regioselective transglycosylation from lactose to the 3-position of 2-acetamido glycosides. when alpha-d-galnac-oc6h4no2-p was used as an acceptor, the enzyme synthesized mainly beta-d-gal-(1-->3)-alpha-d-galnac-oc6h4no2-p with its (1-->6) linked isomer. the use of an inclusion complex of the glycoside acceptor with beta-cd increased the efficiency of transglycosylation by increasing the solubility of the acceptor. in the same way, the use of beta-d ... | 1996 | 8947852 |
| 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 ... | 1996 | 8931150 |
| aspartate aminotransferase from an alkalophilic bacillus contains an additional 20-amino acid extension at its functionally important n-terminus. | aspartate aminotransferase (aspat), responsible for a minor part of the total aspat enzymic activity in alkalophilic bacillus circulans, was purified, its n-terminal amino acid sequence was determined, and its gene was cloned as two separate fragments. dna sequencing showed an open reading frame of 432 amino acids (m(r) 47,439) exhibiting moderately low homology with aspats from other sources. sequence alignment of the enzyme with chicken mitochondrial, chicken cytoplasmic and escherichia coli a ... | 1996 | 8889830 |
| 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 ... | 1996 | 8845760 |
| comparison of ion plasma, vaporized hydrogen peroxide, and 100% ethylene oxide sterilizers to the 12/88 ethylene oxide gas sterilizer. | the performance of a standard gas sterilizer, which uses a mixture of 12% ethylene oxide (eto) and 88% chlorofluorocarbon as the sterilizing gas (12/88), was compared to selected gas, ion plasma, and vaporized hydrogen peroxide (h2o2) sterilizers that do not use chlorofluorocarbons. the effect of serum and salt on sterilizer performance was evaluated. | 1996 | 8835444 |
| some properties of a cyclomaltodextrin-glucanotransferase from bacillus circulans df 9 r type. | the cyclomaltodextrin-glucanotransferase (ec2.4.1.19, cgtase) which was purified to homogeneity from bacillus circulans strain df 9, r type, showed a pi of 5.3 determined by disc-isoelectric focusing, a mw of 78 kda estimated by sds-page with a range of ph of optimal enzymatic activity rather large (4.5-7.5). the thermal stability of the enzyme at 55 degrees c was increased 4-5 times when calcium ion (10 to 100 mm) or alpha-cyclodextrins (10 mm) were added to the preincubation mixtures. the alph ... | 1996 | 8832096 |
| isolation of two strains (s-r type) of bacillus circulans and purification of a cyclomaltodextrin-glucanotransferase. | from wild type inoculum of bacillus circulans df 9 which produce cyclomaltodextrin-glucanotransferase (ec 2.4.1.19, cgtase), two different kinds of colonies were isolated, which correspond to the classical s-r variation. from the culture medium of both colonies grown together a cgtase was purified about 50 fold with a yield of 54% in two steps. from pure r-cell culture the enzyme was purified by about 38 folds with a yield of 79% in only one step, showing a complete homogeneity as judged by a na ... | 1996 | 8832095 |
| 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. | 1996 | 8829541 |
| expression of trichoderma reesei and trichoderma viride xylanases in escherichia coli. | synthetic genes encoding the 190 amino acid trichoderma reesei xylanase ii (trx) and the closely related trichoderma viride xylanases have been synthesized in a two-step procedure. initially, a partial gene encoding amino acids 92-190 was constructed in fusion with the n-terminal half of the bacillus circulans xylanase (bcx). the remaining bcx gene sequence was replaced during the assembly of the coding sequence for amino acids 1-91. expression of the synthetic genes in escherichia coli yielded ... | 1995 | 8829371 |
| crystallization and preliminary x-ray analysis of phosphoserine aminotransferase from bacillus circulans subsp. alkalophilus. | recombinant phosphoserine aminotransferase (ec 2.6.1.52) from bacillus circulans subsp. alkalophilus was crystallized at room temperature from 0.1 m sodium acetate buffer, ph 4.6, and 2% peg 20000, using macroseeding techniques. the crystals diffract x-rays to at least 2.0 a nominal resolution. they belong to space group c2 with unit cell dimensions a = 93.2 a, b = 93.1 a, c = 45.6 a, alpha = 90.0 degrees, beta = 106.8 degrees, gamma = 90.0 degrees. a native data set to 2.3 a has been collected. ... | 1996 | 8819175 |
| secondary structure and nmr assignments of bacillus circulans xylanase. | bacillus circulans xylanase (bcx) is a member of the family of low molecular weight endo-beta-(1,4)-xylanases. the main-chain 1h, 13c, and 15n resonances of this 20.4-kda enzyme were assigned using heteronuclear nmr experiments recorded on a combination of selectively and uniformly labeled protein samples. using chemical shift, noe, j coupling, and amide hydrogen exchange information, 14 beta-strands, arranged in a network of three beta-sheets, and a single alpha-helix were identified in bcx. th ... | 1996 | 8762143 |
| effects of both shortening and lengthening the active site nucleophile of bacillus circulans xylanase on catalytic activity. | the relative positioning of the two carboxyl groups at the active site of glycosidases is crucial to their function and the mechanism followed. the distance between these two groups in bacillus circulans xylanase has been modified by mutagenesis of the catalytic nucleophile glu78. an increase in the separation (glu78asp) results in a large (1600-5000-fold) reduction in the rate of the glycosylation step, but little change in the extent of bond cleavage or proton donation at the transition state. ... | 1996 | 8756474 |
| the pka of the general acid/base carboxyl group of a glycosidase cycles during catalysis: a 13c-nmr study of bacillus circulans xylanase. | the 20 kda xylanase from bacillus circulans carries out hydrolysis of xylan via a two-step mechanism involving a covalent glycosyl-enzyme intermediate. in this double-displacement reaction, glu78 functions as a nucleophile to form the intermediate, while glu172 acts as a general acid catalyst during glycosylation, protonating the departing aglycone, and then as a general base during deglycosylation, deprotonating the attacking water. the dual role of glu172 places specific demands upon its ioniz ... | 1996 | 8756457 |
| phosphoserine aminotransferase from bacillus circulans subsp. alkalophilus: purification, gene cloning and sequencing. | two peaks of aspartate aminotransferase (aspat) catalytic activity were observed during deae chromatography of a protein extract from alkalophilic b. circulans. the enzyme purified from the major peak appeared to be not aspartate but phosphoserine aminotransferase (psat) with a considerably high aspat side activity. the sequence of the enzyme n-terminus was determined, and the psat gene was cloned as two separate fragments. dna sequencing revealed the open reading frame for the psat starting fro ... | 1996 | 8695645 |
| structure of cyclodextrin glycosyltransferase complexed with a maltononaose inhibitor at 2.6 angstrom resolution. implications for product specificity. | crystals of the y195f mutant of cyclodextrin glycosyltransferase from bacillus circulans strain 251 were subjected to a double soaking procedure, in which they were first soaked in a solution containing the inhibitor acarbose and subsequently in a solution containing maltohexaose. the refined structure of the resulting protein-carbohydrate complex has final crystallographic and free r-factors for data in the 8-2.6 angstrom resolution range of 15.0% and 21.5%, respectively, and reveals that a new ... | 1996 | 8672460 |
| bacillus circulans infection of a proximal interphalangeal joint after a clenched-fist injury caused by human teeth. | 1995 | 8654440 | |
| high-yield synthesis of n-acetyllactosamine by regioselective transglycosylation. | the synthesis of n-acetyllactosamine (d-galp beta 1-4d-glcpnac) with very low contamination of its isomer n-acetyllactosamine (d-galp beta 1-6d-glcpnac) was obtained by use of regioselective transglycosylation activity of beta-galactosidase from bacillus circulans using lactose as the donor of d-galp and d-glcpnac as the acceptor. the reaction was conducted at 15 degrees c and at ph 5.0. the incubation time was considerably reduced and the yield improved 100% with respect to the best results so ... | 1996 | 8619828 |
| cloning of a cluster of chitinase genes from aeromonas sp. no. 10s-24. | a gene encoding chitinases from aeromonas sp. no. 10s-24 was cloned into escherichia coli dh5 alpha using puc19, and its nucleotides were sequenced. the chitinase gene was clustered in orfs (open reading frame) 1 to 4, in a 8-kb fragment of dna. orf-1 consisted of 1608 bp encoding 535 amino acid residues, and orf-2 consisted of 1425 bp encoding 474 amino acid residues. orf-3 was 1617 bp long and encodes a protein consisting of 538 amino acids. orf-4 encodes 287 amino acids of the n-terminal regi ... | 1996 | 8605248 |
| secretion of an enzymatically active trichoderma harzianum endochitinase by saccharomyces cerevisiae. | a novel endochitinase agar-plate assay has been developed and used to identify 11 full-length cdnas encoding endochitinase i (enci) from a trichoderma harzianum cdna library by expression in yeast. the 1473-bp chi1 cdna encodes a 424-residue precursor protein including both a signal sequence and a propeptide. the deduced enci amino-acid sequence is homologous to other fungal and bacterial chitinases, and the enzyme cross-reacts with a polyclonal antiserum raised against chitinase a1 from bacillu ... | 1996 | 8598062 |
| overexpression of the bacillus subtilis and circulans xylanases in escherichia coli. | an efficient expression system for a low-molecular mass xylanase in escherichia coli has been developed. a gene encoding the mature bacillus circulans (bc) xylanase was designed to imitate the frequency of degenerate codons used in e. coli. appropriate degenerate codons were used to create multiple unique restriction sites for future mutagenesis studies. the synthetic gene was constructed in two stages, both involving ligation of overlapping oligonucleotides. the synthetic bc gene was then conve ... | 1993 | 8518560 |
| antimicrobial activity determined in strains of bacillus circulans cluster. | wild-type strains of the genus bacillus were screened for antimicrobial activity. two strains exhibited antimicrobial activity against micrococcus luteus and were identified as bacillus polymyxa mir-23 and bacillus circulans mir-13. bacillus polymyxa mir-23 was active against escherichia coli, pseudomonas aeruginosa and aspergillus niger, whereas bacillus circulans mir-13 did not show activity against these microorganisms. bacillus subtilis atcc 6633 and b. polymyxa atcc 10401 were used as stand ... | 1993 | 8500778 |
| cyclomaltodextrin glucanotransferase from bacillus circulans e 192: nitration with tetranitromethane. | nitration of tyrosine residues was performed on bacillus circulans e 192 cyclomaltodextrin glucanotransferase (cgtase) using tetranitromethane (tnm). a maximum of 15 out of 28 tyrosine residues is modified with 8 mm tnm, entailing a concomitant loss of enzymic activity and tryptophan fluorescence. spectroscopic studies suggest that these two phenomena are related to an impairment of the enzyme conformation as a consequence of the tyrosine nitration. the presence of 5 mm acarbose during the cgtas ... | 1993 | 8484906 |
| purification, characterization, gene cloning, and sequencing of a new beta-glucosidase from bacillus circulans subsp. alkalophilus. | an intracellular beta-glucosidase was purified from cell extracts of bacillus circulans subsp. alkalophilus by nad affinity and high-performance anion-exchange chromatographies. the enzyme was active against a wide range of aryl-beta-glucosides and beta-linked disaccharides. the structural gene for beta-glucosidase was cloned in escherichia coli. the beta-glucosidase gene consisted of an open reading frame of 1,350 bp encoding a protein of 450 amino acids with a calculated m(r) of 51,303. the en ... | 1993 | 8481013 |
| cloning of the beta-amylase gene from bacillus cereus and characteristics of the primary structure of the enzyme. | the gene encoding the beta-amylase of bacillus cereus bq10-s1 (spoii) was cloned into escherichia coli jm 109. a sequenced dna fragment of 2,001 bp contains the beta-amylase gene. the n-terminal sequences (avngkg mnpdykaylmaplkki), the c-terminal sequences (shtssw), and the amino acid sequences of the five regions in the beta-amylase molecules were determined. the mature beta-amylase contains 514 amino acid residues with a molecular mass of 57,885 da. the amino acid sequence homology with those ... | 1993 | 8434930 |
| purification and properties of a thermostable chitinase from streptomyces thermoviolaceus opc-520. | a chitinase was purified from the culture filtrate of streptomyces thermoviolaceus opc-520. the enzyme showed a high optimum temperature (70 to 80 degrees c), a high optimum ph level (8.0 to 10.0), and heat stability. this enzyme showed high sequence homology with chitinases from serratia marcescens qmb1466 and bacillus circulans wl-12. | 1993 | 8434929 |
| preparation, isolation, and characterization of novel heterogeneous branched cyclomalto-oligosaccharides having beta-d-galactosyl residue(s) on the side chain. | transgalactosylated products of branched cyclodextrins (glucosyl-alpha cd, -beta cd, -gamma cd, and maltosyl-alpha cd, -beta cd, -gamma cd) were synthesized by beta-d-galactosidases from bacillus circulans and penicillium multicolor using lactose as a donor substrate and branched cds as acceptors. eighteen beta-d-galactosylated branched cds were isolated and purified by hplc. their structures were elucidated by fabms and 13c nmr spectroscopies, and methylation analysis. the chromatographic behav ... | 1993 | 8431940 |
| a convenient synthesis of beta-d-galactosyl disaccharide derivatives using the beta-d-galactosidase from bacillus circulans. | beta-d-gal-(1-->4)-beta-d-glcnac-oc6h4no2-p (p-nitrophenyl n-acetyl-beta-lactosaminide) and beta-d-gal-(1-->6)-beta-d-glcnac-oc6h4no2-p (p-nitrophenyl n-acetyl-beta-isolactosaminide) were regioselectively synthesized from lactose and p-nitrophenyl 2-acetamido-2-deoxy-glucopyranoside, employing transglycosylation by the beta-d-galactosidase from bacillus circulans and by controlling the concentration of organic solvent in the reaction system. the (1-->4)-linked disaccharide was formed exclusively ... | 1993 | 8348555 |
| characteristics of an exochitinase from streptomyces olivaceoviridis, its corresponding gene, putative protein domains and relationship to other chitinases. | streptomyces olivaceoviridis efficiently degrades chitin. shotgun cloning of partially sau3a-cleaved dna using the multicopy vector pij702 and streptomyces lividans 66 as host resulted in the identification of the plasmid pchi o1 which harbours an insert of 4.6 kb. in the presence of chitin as sole carbon source, transformants of s. lividans 66 carrying pchi o1 or its derivatives with smaller inserts overproduced an exochitinase which was purified to homogeneity. the chitin-inducible enzyme with ... | 1993 | 8319677 |
| [primary structure and catalytic properties of extracellular ribonuclease from bacillus circulans]. | a comparative research of individual peptide structures obtained after hydrolysing of bacillus circulans and b. amyloliquefaciens rnases by the glu-specific staphylococcal protease was carried out by means of mass-spectrometry and edman degradation methods. a complete amino acid sequence of b. circulans rnase was determined. gln15, gly65 and gln104 residues in b. amyloliquefaciens rnase were found to be substituted by leu, ala and lys residues in b. circulans rnase, respectively. catalytic prope ... | 1993 | 8285919 |