| evidence for cycloisomaltooligosaccharide production from starch by bacillus circulans t-3040. | bacillus circulans t-3040 produces cycloisomaltooligosaccharide glucanotransferase (citase) and cycloisomaltooligosaccharides (cyclodextrans, cis) when it is grown in media containing dextran as the carbon source. to investigate the effects of carbon sources on citase activity, b. circulans t-3040 was cultured with glucose; sucrose; a mixture of isomaltose, isomaltotriose, and panose (imos); a mixture of maltohexaose and maltoheptaose (g67); dextrin (average degree of polymerization = 36); dextr ... | 2014 | 24463763 |
| characterization of a galactosynthase derived from bacillus circulans β-galactosidase: facile synthesis of d-lacto- and d-galacto-n-bioside. | glycosynthases-retaining glycosidases mutated at their catalytic nucleophile-catalyze the formation of glycosidic bonds from glycosyl fluorides as donor sugars and various glycosides as acceptor sugars. here the first glycosynthase derived from a family 35 β-galactosidase is described. the glu→gly mutant of bgac from bacillus circulans (bgac-e233g) catalyzed regioselective galactosylation at the 3-position of the sugar acceptors with α-galactosyl fluoride as the donor. transfer to 4-nitophenyl α ... | 2014 | 24458919 |
| biochemical, structural, and genetic characterization of tridecaptin a₁, an antagonist of campylobacter jejuni. | bacillus circulans nrrl b-30644 (now paenibacillus terrae) was previously reported to produce srcam 1580, a bacteriocin active against the food pathogen campylobacter jejuni. we have been unable to isolate srcam 1580, and did not find any genetic determinants in the genome of this strain. we now report the reassignment of this activity to the lipopeptide tridecaptin a₁. structural characterization of tridecaptin a1 was achieved through nmr, ms/ms and gc-ms studies. the structure was confirmed th ... | 2014 | 24382692 |
| cgtase-catalysed cis-glucosylation of l-rhamnosides for the preparation of shigella flexneri 2a and 3a haptens. | we report the enzymatic synthesis of α-d-glucopyranosyl-(1→4)-α-l-rhamnopyranoside and α-d-glucopyranosyl-(1→3)-α-l-rhamnopyranoside by using a wild-type transglucosidase in combination with glucoamylase and glucose oxidase. it was shown that bacillus circulans 251 cyclodextrin glucanotransferase (cgtase, ec 2.1.4.19) can efficiently couple an α-l-rhamnosyl acceptor to a maltodextrin molecule with an α-(1→4) linkage, albeit in mixture with the α-(1→3) regioisomer, thus giving two glucosylated ac ... | 2014 | 24376024 |
| detection and characterization of serine and threonine hydroxyl protons in bacillus circulans xylanase by nmr spectroscopy. | hydroxyl protons on serine and threonine residues are not well characterized in protein structures determined by both nmr spectroscopy and x-ray crystallography. in the case of nmr spectroscopy, this is in large part because hydroxyl proton signals are usually hidden under crowded regions of (1)h-nmr spectra and remain undetected by conventional heteronuclear correlation approaches that rely on strong one-bond (1)h-(15)n or (1)h-(13)c couplings. however, by filtering against protons directly bon ... | 2014 | 24306180 |
| molecular cloning and nucleotide sequence of the gene for an alkaline protease from bacillus circulans mtcc 7906. | bacillus circulans mtcc 7906, an extracellular alkaline protease producer was genetically characterized. b. circulans genomic dna was isolated, oligonucleotide primers specific to alkaline protease gene of b. circulans were designed and its pcr amplification was done. the purified pcr product and ptrchisa vector were subjected to restriction digestion with ncoi and hindiii and transformed into escherichia coli dh5-α competent cells. the recombinant expression of alkaline protease gene studied by ... | 2012 | 24293722 |
| recombinant production and characterization of full-length and truncated β-1,3-glucanase pgla from paenibacillus sp. s09. | β-1,3-glucanases catalyze the hydrolysis of glucan polymers containing β-1,3-linkages. these enzymes are of great biotechnological, agricultural and industrial interest. the applications of β-1,3-glucanases is well established in fungal disease biocontrol, yeast extract production and wine extract clarification. thus, the identification and characterization of novel β-1,3-glucanases with high catalytic efficiency and stability is of particular interest. | 2013 | 24283345 |
| x-ray analysis of butirosin biosynthetic enzyme btrn redefines structural motifs for adomet radical chemistry. | the 2-deoxy-scyllo-inosamine (doia) dehydrogenases are key enzymes in the biosynthesis of 2-deoxystreptamine-containing aminoglycoside antibiotics. in contrast to most doia dehydrogenases, which are nad-dependent, the doia dehydrogenase from bacillus circulans (btrn) is an s-adenosyl-l-methionine (adomet) radical enzyme. to examine how btrn employs adomet radical chemistry, we have determined its structure with adomet and substrate to 1.56 å resolution. we find a previously undescribed modificat ... | 2013 | 24048029 |
| β-galactosidase stability at high substrate concentrations. | enzymatic synthesis of galacto-oligosaccharides is usually performed at high initial substrate concentrations since higher yields are obtained. we report here on the stability of β-galactosidase from bacillus circulans at 25, 40, and 60°c in buffer, and in systems with initially 5.0 and 30% (w/w) lactose. in buffer, the half-life time was 220 h and 13 h at 25 and 40°c, respectively, whereas the enzyme was completely inactivated after two hours at 60°c. in systems with 5.0 and 30% (w/w) lactose, ... | 2013 | 24024090 |
| calcium ion contribution to thermostability of cyclodextrin glycosyltransferase is closely related to calcium-binding site caiii. | in the study, we investigated the contribution of ca²⁺ to the thermostability of α-cyclodextrin glycosyltransferase (α-cgtase) from paenibacillus macerans , which has two calcium-binding sites (cai and caii), and β-cgtase from bacillus circulans , which contains an additional calcium-binding site (caiii), consisting of ala315 and asp577. it was found that the contribution of ca²⁺ to the thermostability of two cgtases displayed a marked difference. ca²⁺ affected β-cgtase thermostability significa ... | 2013 | 23968201 |
| cloning and biochemical characterization of an endo-1,4-β-mannanase from the coffee berry borer hypothenemus hampei. | the study of coffee polysaccharides-degrading enzymes from the coffee berry borer hypothenemus hampei, has become an important alternative in the identification for enzymatic inhibitors that can be used as an alternative control of this dangerous insect. we report the cloning, expression and biochemical characterization of a mannanase gene that was identified in the midgut of the coffee berry borer and is responsible for the degradation of the most abundant polysaccharide in the coffee bean. | 2013 | 23965285 |
| crystallization and preliminary x-ray crystallographic analysis of cycloisomaltooligosaccharide glucanotransferase from bacillus circulans t-3040. | bacillus circulans t-3040 cycloisomaltooligosaccharide glucanotransferase (bccitase) catalyses an intramolecular transglucosylation reaction and produces cycloisomaltooligosaccharides from dextran. bccitase was overexpressed in escherichia coli in two different forms and crystallized by the sitting-drop vapour-diffusion method. the crystal of bccitase bearing an n-terminal his₆ tag diffracted to a resolution of 2.3 å and belonged to space group p3₁21, containing a single molecule in the asymmetr ... | 2013 | 23908050 |
| a computational method for the systematic screening of reaction barriers in enzymes: searching for bacillus circulans xylanase mutants with greater activity towards a synthetic substrate. | we present a semi-empirical (pm6-based) computational method for systematically estimating the effect of all possible single mutants, within a certain radius of the active site, on the barrier height of an enzymatic reaction. the intent of this method is not a quantitative prediction of the barrier heights, but rather to identify promising mutants for further computational or experimental study. the method is applied to identify promising single and double mutants of bacillus circulans xylanase ... | 2013 | 23904990 |
| differences in the roles of a glutamine amidotransferase subunit of pyridoxal 5'-phosphate synthase between bacillus circulans and bacillus subtilis. | btrc2 of the butirosin producer bacillus circulans is a non-catalytic subunit of 2-deoxy-scyllo-inosose (doi) synthase that is involved in butirosin biosynthesis, and also a homolog of glutamine amidotransferase subunit (pdxt) of pyridoxal 5'-phosphate (plp) synthase of bacillus subtilis. btrc2 has been found to have functions in b. circulans both in primary and secondary metabolism. in this study, we investigated the properties of pdxt of b. subtilis in order to determine whether the property o ... | 2013 | 23832367 |
| current studies on physiological functions and biological production of lactosucrose. | lactosucrose (o-β-d-galactopyranosyl-(1,4)-o-α-d-glucopyranosyl-(1,2)-β-d-fructofuranoside) is a trisaccharide formed from lactose and sucrose by enzymatic transglycosylation. this rare trisaccharide is a kind of indigestible carbohydrate, has good prebiotic effect, and promotes intestinal mineral absorption. it has been used as a functional ingredient in a range of food products which are approved as foods for specified health uses in japan. using lactose and sucrose as substrates, lactosucrose ... | 2013 | 23828605 |
| effects of dietary arabinoxylan-oligosaccharides (axos) and endogenous probiotics on the growth performance, non-specific immunity and gut microbiota of juvenile siberian sturgeon (acipenser baerii). | we investigated the effects of administration of putative endogenous probiotics lactococcus lactis spp. lactis or bacillus circulans, alone and in combination with arabinoxylan-oligosaccharides (axos), a new class of candidate prebiotics, in juvenile siberian sturgeon (acipenser baerii). eight experimental diets were tested: basal diet (diet 1), basal diet supplemented with 2% axos (diet 2), or l. lactis st g81 (diet 3), l. lactis st g45 (diet 4), b. circulans st m53 (diet 5), l. lactis st g81 + ... | 2013 | 23811408 |
| effects of carbohydrates on the onpg converting activity of β-galactosidases. | the effects of high concentrations of carbohydrates on the o-nitrophenyl β-d-galactopyranoside (onpg) converting activity of β-galactosidase from bacillus circulans are studied to get a better understanding of the enzyme behavior in concentrated and complicated systems in which enzymatic synthesis of galacto-oligosaccharides is usually performed. the components that were tested were glucose, galactose, lactose, sucrose, trehalose, raffinose, vivinal gos, dextran-6000, dextran-70,000, and sarcosi ... | 2013 | 23725091 |
| involvement of gln679, in addition to trp687, in chitin-binding activity of the chitin-binding domain of chitinase a1 from bacillus circulans wl-12. | chitinase a1 (chia1) from bacillus circulans wl-12 comprises an n-terminal catalytic domain, two fibronectin type iii domains, and a c-terminal chitin-binding domain (chbd). the chbd of chia1 (chbdchia1) belongs to carbohydrate-binding module (cbm) family 12 and specifically binds to insoluble or crystalline chitin. it has been suggested that tryptophan-687 (trp687) is involved in the chitin-binding activity of this chbd. site-directed mutagenesis was used to identify additional amino acid resid ... | 2013 | 23694779 |
| strategies for modulating the ph-dependent activity of a family 11 glycoside hydrolase. | the ph-dependent activity of wild-type bacillus circulans xylanase (bcx) is set by the pk(a) values of its nucleophile glu78 and general acid/base glu172. herein, we examined several strategies to manipulate these pk(a) values and thereby shift the ph(opt) at which bcx is optimally active. altering the global charge of bcx through random succinylation had no significant effect. mutation of residues near or within the active site of bcx, but not directly contacting the catalytic carboxyls, either ... | 2013 | 23578322 |
| characterization of β-galactosidase isoforms from bacillus circulans and their contribution to gos production. | a β-galactosidase preparation from bacillus circulans consists of four isoforms called β-gal-a, β-gal-b, β-gal-c, and β-gal-d. these isoforms differ in lactose hydrolysis and galacto-oligosaccharide (gos) synthesis at low substrate concentrations. for this reason, using a selection of the isoforms may be relevant for gos production, which is typically done at high substrate concentrations. at initial lactose concentrations in between 0.44 % and 0.68 % (w/w), β-gal-a showed the least oligosacchar ... | 2013 | 23526073 |
| domain structure and function of α-1,3-glucanase from bacillus circulans ka-304, an enzyme essential for degrading basidiomycete cell walls. | bacillus circulans ka-304 α-1,3-glucanase (agl-ka) includes an n-terminal discoidin domain (ds1), a carbohydrate binding module family 6 (cb6), threonine and proline repeats (tps), a second discoidin domain (ds2), an uncharacterized conserved domain (ucd), and a c-terminal catalytic domain. domain deletion enzymes lacking ds1, cb6, and ds2 exhibited lower α-1,3-glucan-hydrolyzing and -binding activities than the wild type, agl-ka. an α-1,3-glucan binding assay with fluorescent protein fusion pro ... | 2013 | 23470772 |
| immobilization of nisin producer lactococcus lactis strains to chitin with surface-displayed chitin-binding domain. | in this study, nisin producer lactococcus lactis strains displaying cell surface chitin-binding domain (chbd) and capable of immobilizing to chitin flakes were constructed. to obtain chbd-based cell immobilization, usp45 signal sequence with chbd of chitinase a1 enzyme from bacillus circulans was fused with different lengths of prtp (153, 344, and 800 aa) or acma (242 aa) anchors derived from l. lactis. according to the whole cell elisa analysis, chbd was successfully expressed on the surface of ... | 2013 | 23354445 |
| the discoidin domain of bacillus circulans β-galactosidase plays an essential role in repressing galactooligosaccharide production. | the recently cloned β-galactosidase from bacillus circulans atcc 31382, designated bgad, contains a multiple domain architecture including a f5/8 type c domain or a discoidin (ds) domain in the c-terminal peptide region. here we report that the ds domain plays an essential role in repressing the production of galactooligosaccharides (goss). we prepared deletion mutants and point-mutated forms of rbgad-a (deletion of the bgad signal peptide) to compare their reaction behaviors. the yields of goss ... | 2013 | 23291776 |
| production of alkaline protease by solvent-tolerant alkaliphilic bacillus circulans mtcc 7942 isolated from hydrocarbon contaminated habitat: process parameters optimization. | in the present investigation, a newly isolated organic solvent-tolerant and alkaliphilic bacterial strain was reported from a hydrocarbon (gasoline and diesel) contaminated soil collected from the petrol station, shirpur (india). the strain was identified as bacillus circulans mtcc 7942, based on phenotype, biochemical, and phylogenetic analysis of 16s rrna gene sequence. the capability of bacillus circulans to secrete an extracellular, thermostable, alkaline protease and grow in the presence of ... | 2013 | 25937965 |
| synthesis of prebiotic carbohydrates derived from cheese whey permeate by a combined process of isomerisation and transgalactosylation. | lactose from cheese whey permeate (wp) was efficiently isomerised to lactulose using egg shell, a food-grade catalyst, and the subsequent transgalactosylation reaction of this mixture with β-galactosidase from bacillus circulans gave rise to a wide array of prebiotic carbohydrates derived from lactose and lactulose. | 2013 | 23096763 |
| in silico identification of catalytic residues and domain fold of the family gh119 sharing the catalytic machinery with the α-amylase family gh57. | the glycoside hydrolase family 119 (gh119) contains the α-amylase from bacillus circulans and five other hypothetical proteins. until now, nothing has been reported on the catalytic residues and catalytic-domain fold of gh119. based on a detailed in silico analysis involving sequence comparison in combination with blast searches and structural modelling, an unambiguous relationship was revealed between the families gh119 and gh57. this includes sharing the catalytic residues, i.e. glu231 and asp ... | 2012 | 22819817 |
| kinetics and design relation for enzymatic conversion of lactose into galacto-oligosaccharides using commercial grade β-galactosidase. | the enzymatic synthesis of galacto-oligosaccharides (gos) from lactose was studied using commercial grade β-galactosidase (biolacta fn5) from bacillus circulans. the reaction was carried out under free enzyme condition varying initial lactose concentration (ilc: 55-525 g/l), enzyme concentration (0.05-1.575 g/l), temperature (30-50°c) and ph (5.0-6.0). reaction mixture compositions were analyzed utilizing high performance liquid chromatography (hplc). a maximum gos formation of 39% (dry basis) w ... | 2012 | 22695078 |
| galacto-oligosaccharide synthesis from lactose solution or skim milk using the β-galactosidase from bacillus circulans. | the synthesis of galacto-oligosaccharides (gos) catalyzed by a novel commercial preparation of β-galactosidase from bacillus circulans (biolactase) was studied, and the products were characterized by ms and nmr. using 400 g/l lactose and 1.5 enzyme units per milliliter, the maximum gos yield, measured by hpaec-pad analysis, was 165 g/l (41% w/w of total carbohydrates in the mixture). the major transgalactosylation products were the trisaccharide gal-β(1→4)-gal-β(1→4)-glc and the tetrasaccharide ... | 2012 | 22676418 |
| hydrophobic interaction network analysis for thermostabilization of a mesophilic xylanase. | one widely known drawback of enzymes is their instability in diverse conditions. the thermostability of enzymes is particularly relevant for industrial applications because operation at high temperatures has the advantage of a faster reaction rate. protein stability is mainly determined in this study by intra-molecular hydrophobic interactions that have a collective and 3-dimensional clustering effect. to interpret the thermostability of enzymes, network analysis was introduced into the protein ... | 2012 | 22642881 |
| bacillus gottheilii sp. nov., isolated from a pharmaceutical manufacturing site. | a novel gram-staining-positive, rod-shaped, motile, strictly aerobic, endospore-forming bacterium, designated wcc 4585(t), was isolated from a pharmaceutical production line. the organism grew optimally at 30 °c, at ph 8 and in the presence of 0.5 % (w/v) nacl. oval endospores were formed subterminally and terminally in swollen sporangia. the cell-wall diamino acid was meso-diaminopimelic acid (type a1γ) and the genomic dna g+c content was 38.7 mol%. the major menaquinone was mk-7. the cellular ... | 2013 | 22634699 |
| biochemical characterization of a novel cycloisomaltooligosaccharide glucanotransferase from paenibacillus sp. 598k. | cycloisomaltooligosaccharide glucanotransferase (citase; ec 2.4.1.248), a member of the glycoside hydrolase family 66 (gh66), catalyzes the intramolecular transglucosylation of dextran to produce cycloisomaltooligosaccharides (cis; cyclodextrans) of varying lengths. eight ci-producing bacteria have been found; however, citase from bacillus circulans t-3040 (citase-t3040) is the only ci-producing enzyme that has been characterized to date. in this study, we report the gene cloning, enzyme charact ... | 2012 | 22542750 |
| evaluation of dna extraction methods and their clinical application for direct detection of causative bacteria in continuous ambulatory peritoneal dialysis culture fluids from patients with peritonitis by using broad-range pcr. | the aims of this study were to compare several dna extraction methods and 16s rdna primers and to evaluate the clinical utility of broad-range pcr in continuous ambulatory peritoneal dialysis (capd) culture fluids. | 2012 | 22389878 |
| structural analysis, enzymatic characterization, and catalytic mechanisms of β-galactosidase from bacillus circulans sp. alkalophilus. | crystal structures of native and α-d-galactose-bound bacillus circulans sp. alkalophilus β-galactosidase (bca-β-gal) were determined at 2.40 and 2.25 å resolutions, respectively. bca-β-gal is a member of family 42 of glycoside hydrolases, and forms a 460 kda hexameric structure in crystal. the protein consists of three domains, of which the catalytic domain has an (α/β)(8) barrel structure with a cluster of sulfur-rich residues inside the β-barrel. the shape of the active site is clearly more op ... | 2012 | 22385475 |
| an alkaline protease from bacillus circulans bm15, newly isolated from a mangrove station: characterization and application in laundry detergent formulations. | an investigation on the properties of an alkaline protease secreted by bacillus circulans bm15 strain isolated from a mangrove sediment sample was carried out in order to characterize the enzyme and to test its potency as a detergent additive. the protease was purified to apparent homogeneity by ammonium sulphate precipitation and was a 30-kda protease as shown by sds-page and its proteolytic activity was detected by casein zymography. it had optimum activity at ph 7, was stable at alkaline ph r ... | 2007 | 23100681 |
| effects of inoculation of phosphate-solubilizing microorganisms and an arbuscular mycorrhizal fungus on mungbean grown under natural soil conditions. | the effect of inoculation of the phosphate-solubilizing microorganisms (psm) bacillus circulans and cladosporium herbarum and the arbuscular mycorrhizal (am) fungus glomus fasciculatum with or without mussoorie rockphosphate (mrp) was studied in a p-deficient natural non-disinfected sandy soil on mungbean (vigna radiata). the am levels increased following the addition of mrp or inoculation with psm or g. fasciculatum. both grain and straw yield of mungbean increased following inoculation with ps ... | 1998 | 24578050 |
| characterization of the immobilized β-galactosidase c from bacillus circulans and the production of β(1→3)-linked disaccharides. | a recombinant β-galactosidase, which was obtained from the β-galactosidase c gene of bacillus circulans and cleaves the non-reducing end galactosyl residue of β(1→3)-linkages selectively, was immobilized using cnbr-sepharose. although the effect of ph was not changed by the immobilization, the thermostability and stability in the presence of dmf were increased. optimization of the transglycosylation using para-nitrophenyl β-d-galactopyranoside as a donor and benzyl-α-d-n-acetylgalactosaminide as ... | 1998 | 27396997 |
| purification and some properties of p-nitrophenyl-β-d-glucoside-hydrolyzing enzymes in culture filtrate of bacillus circulans ka-304 grown on cell-wall preparation of schizophyllum commune. | hydrolyzing activities toward p-nitrophenyl (p-np)-β-d-glucoside and laminarin in a culture filtrate of bacillus circulans ka-304, which has been observed to form protoplasts from schizophyllum commune mycelia, increased when the bacterium was grown on a cell-wall preparation (cwp) of s. commune or laminarin as a carbon source. an analysis of the filtrate with the cwp suggested occurrence of two major p-np-β-d-glucoside-hydrolyzing enzymes (β-d-glucosidases i and ii) and a laminarin-hydrolyzing ... | 1998 | 27393352 |
| purification and properties of β-amylase from bacillus circulans s31. | a thermotolerant β-amylase was purified from bacillus circulans s31 isolated from soil in hong kong. the purified enzyme has an m r of 64 kda and was stable at 50°c and ph 7.0 for 30 min. its k m for starch was 0.9 mg/ml with a v max of 0.3 mg/min. it was not activated by any metal ion although sulphydrys reagents were inhibitory. | 1994 | 24421144 |
| production of a novel extracellular polysaccharide by a bacillus strain isolated from soil. | a bacterium that was isolated from soil and identified as bacillus circulans was found to produce a highly viscous extracellular polysaccharide when it was grown aerobically in a medium containing glucose as a sole source of carbon. the product was characterized by tlc and gc analyses as a novel heteropolysaccharide consisted of rhamnose, mannose, galactose, and mannuronic acid as sugar components. a maximal yield of polysaccharide reached about 2 g/liter by jar-fermentor culture at 30°c for 48 ... | 1992 | 27280807 |
| purification and some properties of chitinase b1 from bacillus circulans wl-12. | | 1992 | 27280674 |
| properties of a highly viscous polysaccharide produced by a bacillus strain isolated from soil. | chemical and theological properties of a highly viscous and acidic polysaccharide produced by a soil bacterium identified as bacillus circulans are described. the molecular weight of the native polysaccharide was about 116 × 10(4) by gel filtration with hplc. the molar ratio of d-galactose, n-mannose, and l-rhamnose contained in the polysaccharide as neutral sugar components was 1.3:1:2. the viscosity of 1% solution of the polysaccharide was about 5000 cp, which was higher than that of guar gum, ... | 1992 | 27280661 |
| a chitin film containing basic fibroblast growth factor with a chitin-binding domain as wound dressings. | basic fibroblast growth factor (bfgf) can stimulate wound healing. however, consistent delivery of bfgf has many disadvantages. to decrease their instability and diffusible, we introduced chitin-binding domain (chtbd) into bfgf. two expression plasimids were constructed. the first one (named bfgf) contained bfgf (154 amino acids), the second (named chtbd-bfgf) contained bfgf and the chtbd (54 amino acids). chtbd was derived from chitinase a1 (chia1) of bacillus circulans wl-12. the recombinant p ... | 2017 | 28821125 |
| an atypical interaction explains the high-affinity of a non-hydrolyzable s-linked 1,6-α-mannanase inhibitor. | the non-hydrolyzable s-linked azasugars, 1,6-α-mannosylthio- and 1,6-α-mannobiosylthioisofagomine, were synthesized and shown to bind with high affinity to a family 76 endo-1,6-α-mannanase from bacillus circulans. x-ray crystallography showed an atypical interaction of the isofagomine nitrogen with the catalytic acid/base. molecular dynamics simulations reveal that the atypical binding results from sulfur perturbing the most stable form away from the nucleophile interaction preferred for the o-l ... | 2017 | 28766587 |
| construction and functional characterization of truncated versions of recombinant keratanase ii from bacillus circulans. | there is a need for degradative enzymes in the study of glycosaminoglycans. many of these enzymes are currently available either in their natural or recombinant forms. unfortunately, progress in structure-activity studies of keratan sulfate (ks) have been impeded by the lack of a commercially available endo-β-n-acetylglucosaminidase, keratantase ii. the current study uses a recently published sequence of a highly thermostable keratanase ii identified in bacillus circulans to clone and express a ... | 2017 | 28752383 |
| secretory expression of β-mannanase from bacillus circulans nt 6.7 in lactobacillus plantarum. | the β-mannanase gene of bacillus circulans nt 6.7 was successfully cloned in lactobacillus plantarum wcfs1 using the psip403 expression vector and secreted to the supernatant rather than accumulated in the cells. the highest activity was achieved by controlling the ph at 6 during cultivation. maximum mannanase activities detected in the supernatant and cell-free extract of 200 ml mrs broth were 8.2 and 0.86 u/ml, respectively. enzyme activity in the supernatant increased to 27 u/ml by fermentati ... | 2017 | 28712957 |
| biosurfactant production from pseudomonas taiwanensis l1011 and its application in accelerating the chemical and biological decolorization of azo dyes. | dye dispersion and the interaction efficiency between azoreductases and dye molecules are rate-limiting steps for the decolorization of azo dyes. in this study, a biosurfactant-producing strain, pseudomonas taiwanensis l1011, was isolated from crude oil. to increase the yield of the biosurfactant bs-l1011 from p. taiwanensis l1011, culture conditions were optimized including temperature, initial ph, carbon source, nitrogen source and c/n ratio. a maximum yield of 1.12g/l of bs-l1011 was obtained ... | 2017 | 28689070 |
| the structure of rbmb from streptomyces ribosidificus, an aminotransferase involved in the biosynthesis of ribostamycin. | aminoglycoside antibiotics represent a classical group of antimicrobials first discovered in the 1940s. due to their ototoxic and nephrotoxic side effects, they are typically only used against gram negative bacteria which have become resistant to other therapeutics. one family of aminoglycosides includes such compounds as butirosin, ribostamycin, neomycin, and kanamycin, amongst others. the common theme in these antibiotics is that they are constructed around a chemically stable aminocyclitol un ... | 2017 | 28685903 |
| synthesis and characterization of novel astragalin galactosides using β-galactosidase from bacillus circulans. | astragalin (kaempferol-3-o-β-d-glucopyranoside, ast) is a kind of flavonoid known to have anti-oxidant, anti-hiv, anti-allergic, and anti-inflammatory effects. it has low solubility in water. in this study, novel astragalin galactosides (ast-gals) were synthesized using β-galactosidase from bacillus circulans and reaction conditions were optimized to increase the conversion yield of astragallin. purified ast-gal1 (11.6% of ast used, w/w) and ast-gal2 (6.7% of ast used, w/w) were obtained by medi ... | 2017 | 28554386 |
| biochemical characterization of the functional roles of residues in the active site of the β-galactosidase from bacillus circulans atcc 31382. | the β-galactosidase enzyme from bacillus circulans atcc 31382 bgad is widely used in the food industry to produce prebiotic galactooligosaccharides (gos). recently, the crystal structure of a c-terminally truncated version of the enzyme (bgad-d) has been elucidated. the roles of active site amino acid residues in β-galactosidase enzyme reaction and product specificity have remained unknown. on the basis of a structural alignment of the β-galactosidase enzymes bgad-d from b. circulans and bgaa fr ... | 2017 | 28538097 |
| complete genome sequence of the bacterium bacillus circulans jordan strain 32352. | here, we report the complete genome sequence for the bacillus circulans jordan strain 32352. this species is a soil dwelling bacterium that expresses glycosyl hydrolase enzymes degrading pneumococcal capsular polysaccharides. | 2017 | 28495770 |
| refolding the unfoldable: a systematic approach for renaturation of bacillus circulans xylanase. | xylanases are important polysaccharide-cleaving catalysts for the pulp and paper, animal feeds and biofuels industries. they have also proved to be valuable model systems for understanding enzymatic catalysis, with one of the best studied being the gh11 xylanase from bacillus circulans (bcx). however, proteins from this class are very recalcitrant to refolding in vitro. this both limits their high level expression in heterologous hosts, and prevents experimental approaches, such as peptide ligat ... | 2017 | 28466501 |
| fusion of a family 20 carbohydrate-binding module (cbm20) with cyclodextrin glycosyltransferase of geobacillus sp. chb1 improves catalytic efficiency. | cyclodextrin glycosyltransferase (cgtase) is an important industrial enzyme for production of cyclodextrins (cds) from starch by intramolecular transglycosylation. cgtase consists of five domains labeled a to e. for optimizing catalytic activity of cgtase, cgtase of geobacillus sp. was fused with the family 20 carbohydrate-binding module (cbm) of the bacillus circulans strain 251 cgtase. the cbmbc251 that has a low binding free energy with maltohexaose, was selected by in silico design. then the ... | 2017 | 28422446 |
| an efficient process for obtaining prebiotic oligosaccharides derived from lactulose using isomerized and purified whey permeate. | one of the most promising uses of whey permeate (wp) is the synthesis of prebiotic oligosaccharides. herein, commercial wp was submitted to chemical isomerization catalysed by sodium borate at an alkaline ph and subsequent purification using anion-exchange resins to remove boron. subsequently, purified mixtures were used to synthesize prebiotic oligosaccharides using β-galactosidase from bacillus circulans. | 2017 | 28417455 |