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deletion analysis of regions at the c-terminal part of cycloisomaltooligosaccharide glucanotransferase from bacillus circulans t-3040.cycloisomaltooligosaccharide glucanotransferase (citase) belongs to glycoside hydrolase family 66. according to the sequence alignment of enzymes in the same family, we divided the structure of citase into five regions from the n terminus to the c terminus: an n-terminal conserved region (ser1-gly403), an insertion region (r1; tyr404-tyr492), two conserved regions (r2; glu493-ser596 and r3; gly597-met700), and a c-terminal variable region (r4; lys701-ser934). citase catalyzes the synthesis of cy ...201021193067
n-terminal region of chitinase i of bacillus circulans ka-304 contained new chitin-biding domain.chitinase i (chi1) of bacillus circulans ka-304 forms protoplasts from schizophyllum commune mycelia when the enzyme is combined with a-1,3-glucanase of b. circulans ka-304. chi1 consists of an n-terminal unknown region and a c-terminal catalytic region classified into the glycoside hydrolase family-19 type. an n-terminal region-truncated mutant of chi 1 (catchi1), which was expressed in escherichia coli rosetta-gami b (de3), lost colloidal chitin- and powder chitin-binding activities. the collo ...201121307593
causes of the production of multiple forms of ß-galactosidase by bacillus circulans.the presence of multiple types of ß-galactosidases in a commercial enzyme preparation from bacillus circulans atcc 31382 and differences in their transgalactosylation activity were investigated. four ß-galactosidases, ß-gal-a, ß-gal-b, ß-gal-c, and ß-gal-d, which were immunologically homologous, were isolated and characterized. the n-terminal amino acid sequences of all of the enzymes were identical and biochemical characteristics were similar, except for galactooligosaccharide production. ß-gal ...201121307599
cloning, expression and characterization of a new aspartate aminotransferase from bacillus subtilis b3.in the present study, we report the identification of a new gene from the bacillus subtilis b3 strain (aatb3), which comprises 1308 bp encoding a 436 amino acid protein with a monomer molecular weight of 49.1 kda. phylogenetic analyses suggested that this enzyme is a member of the ib subgroup of aspartate aminotransferases (aats; ec 2.6.1.1), although it also has conserved active residues and thermostability characteristic of ia-type aats. the asp232, lys270 and arg403 residues of aatb3 play a k ...201121332942
a comparative study of the regioselectivity of the ß-galactosidases from kluyveromyces lactis and bacillus circulans in the enzymatic synthesis of n-acetyl-lactosamine in aqueous media.the enzymatic synthesis of n-acetyl-lactosamine (lacnac) was studied in aqueous media with high substrate concentrations using the transgalactosylation of n-acetyl-d-glucosamine (glcnac), starting from lactose as a galactosyl donor. the efficiency and regioselectivity of the ß-galactosidases from kluyveromyces lactis (klßgal) and bacillus circulans (bcßgal) were compared. the reaction was optimized by varying the experimental conditions (ph, catalytic activity concentration, and mass concentrati ...201121344676
effect of the substrate concentration and water activity on the yield and rate of the transfer reaction of ß-galactosidase from bacillus circulans.prebiotic galactosyl oligosaccharides (gos) are produced from lactose by the enzyme ß-galactosidase. it is widely reported that the highest gos levels are achieved when the initial lactose concentration is as high as possible; however, little evidence has been presented to explain this phenomenon. using a system composed of the commercial ß-galactosidase derived from bacillus circulans known as biolacta fn5, lactose and sucrose, the relative contribution of water activity, and substrate availabi ...201121375323
impact of chlorophenols on microbiota of an unpolluted acidic soil: microbial resistance and biodegradation.the impact of 2-monochlorophenol (mcp), 2,4,6-trichlorophenol (tcp) and pentachlorophenol (pcp) on the microbial community of an acidic forest soil was studied under controlled laboratory conditions by spiking microcosms with the pollutants at concentrations ranging from 0.1 to 5000 mg kg(-1) . a decrease in the cumulative respirometric values and changes in the bacterial and fungal community composition were detected at 1000 mg mcp kg(-1) , 100 mg tcp kg(-1) and 100 and 1000 mg pcp kg(-1) . how ...201121426365
[expression of modified oxidase of d-aminoacids of trigonopsis variabilis in methylotrophic yeasts pichia pastoris].effective recombinant strains pichia pastoris that produce functionally active hybrid of trigonopsis variabilis d-aminoacids bond with chitin-connecting domain of chitinase a1 of bacillus circulans (daocbd) were obtained. the dependence of daocbd production levels from production of the number of copies of "expression cassette" integrated in the aox1 locus of recombinant strains was studied. it was indicated that synthesized daocbd may be easily purified and immobilized on chitin sorbents and po ...201121442919
an atomic force microscopy study of galleria mellonella apolipophorin iii effect on bacteria.apolipophorin iii (apolp-iii) is an abundant hemolymph protein involved in lipid transport and immune response in insects. as revealed by live/dead staining, incubation of gram-negative and gram-positive bacteria in the presence of galleria mellonella apolp-iii led to growth inhibition of selected bacteria. an atomic force microscopy (afm) study of bacterial cells after apolp-iii treatment showed considerable alterations in the cell surface of bacillus circulans, klebsiella pneumoniae and salmon ...201121453676
enhancing the stability of colloidal silver nanoparticles using polyhydroxyalkanoates (pha) from bacillus circulans (mtcc 8167) isolated from crude oil contaminated soil.polyhydroxyalkanoate (pha) was produced by growing bacillus circulans (mtcc 8167) in the specific detection medium. the identification of the polymer as pha was confirmed by fluorescence microscopy. the pha was purified and characterized using ft-ir. the silver nanoparticles (snp) were synthesized from agno(3) in the dispersed colloids of pha (0.085%) using nabh(4) (sodium borohydrate as reducing agent). the stability was tested using wave length scanning with a uv-vis spectrophotometer and fina ...201121565473
isolation of glucosidase and phospholipase positive bacillus circulans on aloa medium.aim:  to report the growth of glucosidase and phospholipase positive bacteria on agar listeria according to ottaviani and agosti (aloa) different from listeria monocytogenes, listeria ivanovii and bacillus cereus. methods and results:  raw water-buffalo milk was analysed according to en iso 11290. streaking of fraser broth on aloa resulted in green colonies with an opaque halo after 48 h at 30°c. colonies were transferred onto tryptone soya yeast extract agar and showed cultural characteristics ...201121575023
thermal and chemical denaturation of bacillus circulans xylanase: a biophysical chemistry laboratory module.a number of institutions have been, or are in the process of, modifying their biochemistry major to include some emphasis on the quantitative physical chemistry of biomolecules. sometimes this is done as a replacement for part for the entire physical chemistry requirement, while at other institutions this is incorporated as a component into the traditional two-semester biochemistry series. the latter is the model used for biochemistry and molecular biology majors at the university of richmond, w ...200821591232
cloning and expression of a β-galactosidase gene of bacillus circulans.a gene of β-galactosidase from bacillus circulans atcc 31382 was cloned and sequenced on the basis of n-terminal and internal peptide sequences isolated from a commercial enzyme preparation, biolacta(®). using the cloned gene, recombinant β-galactosidase and its deletion mutants were overexpressed as his-tagged proteins in escherichia coli cells and the enzymes expressed were characterized.201121670516
molecular phylogenetic diversity of bacillus community and its temporal-spatial distribution during the swine manure of composting.in order to obtain the diversity and temporal-spatial distribution of bacillus community during the swine manure composting, we utilized traditional culture methods and the modern molecular biology techniques of polymerase chain reaction-restriction fragment length polymorphism (pcr-rflp) and -denaturing gradient gel electrophoresis (pcr-dgge). bacillus species were firstly isolated from the composting. based on temperature changes, the temporal-spatial characteristics of total culturable bacill ...201121701982
Antibacterial activity of different degree of hydrolysis of palm kernel expeller peptides against spore-forming and non-spore-forming bacteria.The goal of this study was to determine inhibitory effect of palm kernel expeller (PKE) peptides of different degree of hydrolysis (DH %) against spore-forming bacteria Bacillus cereus, Bacillus circulans, Bacillus coagulans, Bacillus licheniformis, Bacillus megaterium, Bacillus pumilus, Bacillus stearothermophillus, Bacillus subtilis, Bacillus thuringiensis, Clostridium perfringens; and non-spore-forming bacteria Escherichia coli, Lisinibacillus sphaericus, Listeria monocytogenes, Pseudomonas a ...201121848644
Structure, dynamics, and ionization equilibria of the tyrosine residues in Bacillus circulans xylanase.We have developed NMR spectroscopic methods to investigate the tyrosines within Bacillus circulans xylanase (BcX). Four slowly exchanging buried tyrosine hydroxyl protons with chemical shifts between 7.5 and 12.5 ppm were found using a long-range (13)C-HSQC experiment that exploits the (3)J(CH) coupling between the ring (1)H(?) and (13)C(e) nuclei. The NMR signals from these protons were assigned via (13)C-tyrosine selective labelling and a suite of scalar and (13)C,(15)N-filtered/edited NOE cor ...201121912982
dissecting electrostatic interactions in bacillus circulans xylanase through nmr-monitored ph titrations.nmr-monitored ph titration curves of proteins provide a rich source of structural and electrostatic information. although relatively straightforward to measure, interpreting ph-dependent chemical shift changes to obtain site-specific acid dissociation constants (pk (a) values) is challenging. in order to analyze the biphasic titrations exhibited by the side chain (13)c(γ) nuclei of the nucleophilic glu78 and general acid/base glu172 in bacillus circulans xylanase, we have ...201121947911
Hydrophobic interaction chromatography on octyl sepharose--an approach for one-step platform purification of cyclodextrin glucanotransferases.Cyclodextrin glucanotransferase (CGTase) from Bacillus circulans ATCC 21783 was concentrated by ultrafiltration and subsequently purified by hydrophobic interaction chromatography on Octyl Sepharose 4 fast flow. The matrix was able to bind selectively to the enzyme at a very low ammonium sulfate concentration of 0.67 M and enzyme desorption was performed by decreasing gradient of the salt. The overall recovery was 80% with 689-fold purity. CGTases derived from four soil isolates and Toruzyme, th ...201121967336
cloning of an endoglycanase gene from paenibacillus cookii and characterization of the recombinant enzyme.an endoglycanase gene of paenibacillus cookii ss-24 was cloned and sequenced. this pgl8a gene had an open reading frame of 1,230 bp that encoded a putative signal sequence (31 amino acids) and mature enzyme (378 amino acids: 41,835 da). the enzyme was most homologous to a β-1,3-1,4-glucanase of bacillus circulans wl-12 with 84% identity. the recombinant enzyme hydrolyzed carboxymethyl cellulose, swollen celluloses, chitosan and lichenan but not avicel, chitin powder or xylan. with chitosan as th ...201121972145
the residue 179 is involved in product specificity of the bacillus circulans df 9r cyclodextrin glycosyltransferase.cyclodextrin glycosyltransferases (cgtases) are important enzymes in biotechnology because of their ability to produce cyclodextrin (cd) mixtures from starch whose relative composition depends on enzyme source. a multiple alignment of 46 cgtases and shannon entropy analysis allowed us to find differences and similarities that could be related to product specificity. interestingly, position 179 has gly in all the cgtases except in that from bacillus circulans df 9r which possesses gln. the absenc ...201121993482
expression of a bacterial chitosanase in rice plants improves disease resistance to the rice blast fungus magnaporthe oryzae.plant fungal pathogens change their cell wall components during the infection process to avoid degradation by host lytic enzymes, and conversion of the cell wall chitin to chitosan is likely to be one infection strategy of pathogens. thus, introduction of chitosan-degradation activity into plants is expected to improve fungal disease resistance. chitosanase has been found in bacteria and fungi, but not in higher plants. here, we demonstrate that chitosanase, cho1, from bacillus circulans mh-k1 h ...201122044963
Extracellular production of cycloisomaltooligosaccharide glucanotransferase and cyclodextran by a protease-deficient Bacillus subtilis host-vector system.A cycloisomaltooligosaccharide (CI; cyclodextran) production system was developed using a Bacillus subtilis expression system for the cycloisomaltooligosaccharide glucanotransferase (CITase) gene. The CITase gene of Bacillus circulans T-3040, along with the a-amylase promoter (PamyQ) and amyQ signal sequence of Bacillus amyloliquefaciens, was cloned into the Bacillus expression vector pUB110 and subsequently expressed in B. subtilis strain 168 and its alkaline (aprE) and neutral (nprE) protease- ...201122075636
Effect of Bacillus subtilis BsuM restriction-modification on plasmid transfer by polyethylene glycol-induced protoplast fusion.Polyethylene glycol (PEG)-induced cell fusion is a promising method to transfer larger DNA from one cell to another than conventional genetic DNA transfer systems. The laboratory strain Bacillus subtilis 168 contains a restriction (R) and modification (M) system, BsuM, which recognizes the sequence 5'-CTCGAG-3'. To study whether the BsuM system affects DNA transfer by the PEG-induced cell fusion between R(+)M(+) and R(-)M(-) strains, we examined transfer of plasmids pHV33 and pLS32neo carrying n ...201122092861
First report of a bifunctional chitinase/lysozyme produced by Bacillus pumilus SG2.Bacillus pumilus SG2 isolated from high salinity ecosystem in Iran produces two chitinases (ChiS and ChiL) and secretes them into the medium. In this study, chiS and chiL genes were cloned in pQE-30 expression vector and were expressed in the cytoplasm of Escherichia coli strain M15. The recombinant proteins were purified using Ni-NTA column. The optimum pH and optimum temperature for enzyme activity of ChiS were pH 6, 50°C; those of ChiL were pH 6.5, 40°C. The purified chitinases showed antifun ...201122112904
bio-plastic (p-3hb-co-3hv) from bacillus circulans (mtcc 8167) and its biodegradation.polyhydroxyalkanoates (phas) are naturally occurring polyesters synthesized by bacteria for carbon and energy storage and it has commercial potential as bioplastic. the bacterial species bacillus circulans mtcc 8167, isolated from crude oil contaminated soil, can efficiently produce medium chain length polyhydroxyalkanoates (p-3hb-co-3hv) from cheap carbon sources like dextrose. the molecular mass of p-3hb-co-3hv was reported as 5.1×10(4)da with polydispersity index of 1.21 by gel permeation chr ...201122154099
fatal sepsis by bacillus circulans in an immunocompromised patient.an immunosuppressed man was admitted to hospital with diarrhea and a history of urinary tract infection. he was subjected to treatment with antibiotics. the patient died of putative severe sepsis. the etiological agent was a carbapenemase producing isolate of bacillus circulans with resistance to all prescribed antimicrobial agents.201122347600
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 ...201222385475
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.201222389878
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 ...201222542750
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 ...201322634699
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 ...201222642881
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 ...201222676418
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 ...201222695078
bacillus spp. toxicity against haemonchus contortus larvae in sheep fecal cultures.the gastrointestinal nematode haemonchus contortus is a major productivity constraint in sheep. in this study, the nematicidal effects of bacillus circulans, bacillus cereus, bacillus thuringiensis var. israelensis, bt. var. osvaldocruzi, bt. var. morrisoni, and bt. var. kurstaki were assessed in free-living larval stages of h. contortus. a spore-crystal suspension containing approximately 2×10(8)ufc/ml of each strain was added to sheep feces that were naturally infected with h. contortus eggs, ...201222728159
novel thermostable lipase from bacillus circulans iiib153: comparison with the mesostable homologue at sequence and structure level.thermophilic bacillus circulans iiib153 isolated from hot springs of north west himalayas, india, produced an extracellular lipase, which exhibited significant biofilm disruption property on the static biofilm disruption model with a single species of actinomyces viscosous. the gene encoding the lipase was cloned and overexpressed in escherichia coli. recombinant bacillus circulans lipase (bcl), a monomer with molecular mass of 43 kda also exhibited significant biofilm disruption activity. the e ...201122806795
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 ...201222819817
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.201323096763
antagonistic and antimicrobial activities of some bacterial isolates collected from soil samples.thirty seven bacterial cultures isolated from soil samples obtained from different locations were tested for their antagonistic activity against some fungal pathogens, viz., sclerotium rolfsii, fusarium oxysporum and rhizoctonia solani, causal agents of collar rot of sunflower, wilts and root rots, respectively. among them, 5 bacterial strains, viz., a1 6 (bacillus sphaericus), k1 24 (pseudomonas fluorescens), m1 42 (bacillus circulans), m1 66 (bacillus brevis) and t1 22 (bacillus brevis) showed ...200723100644
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 ...200723100681
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 ...201323291776
detailed analysis of galactooligosaccharides synthesis with β-galactosidase from aspergillus oryzae.the synthesis of galactooligosaccharides (gos) catalyzed by β-galactosidase from aspergillus oryzae (enzeco) was studied. using 400 g/l of lactose and 15 u/ml, maximum gos yield, measured by hpaec-pad, was 26.8% w/w of total carbohydrates, obtained at approximately 70% lactose conversion. no less than 17 carbohydrates were identified; the major transgalactosylation product was 6'-o-β-galactosyl-lactose, representing nearly one-third (in weight) of total gos. in contrast with previous reports, th ...201323330921
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 ...201323354445
hierarchical meso-macroporous silica grafted with glyoxyl groups: opportunities for covalent immobilization of enzymes.hierarchical meso-macroporous silica (average mesopore diameter 20 nm) was synthesized and chemically modified to be used as a support for the immobilization of lipases from candida antarctica b and alcaligenes sp. and β-galactosidases from bacillus circulans and aspergillus oryzae. catalytic activities and thermal stabilities of enzymes immobilized by multipoint covalent attachment in silica derivatized with glyoxyl groups were compared with those immobilized in glyoxyl-agarose, assessing bioca ...201323416689
analysis of the bacterial diversity existing on animal hide and wool: development of a preliminary pcr-restriction fragment length polymorphism fingerprint database for identifying isolates.twenty-one bacterial strains were isolated from imported cattle hide and rabbit wool using two types of media, nutrient broth, and nutrient broth with serum. the bacteria identified were brevibacillus laterosporus, leclercia adecarboxylata, peptococcus niger, bacillus circulans, raoultella ornithinolytica, bacillus subtilis, bacillus cereus, bacillus thermobacillus, bacillus choshinensis, bacillus sphaericus, acinetobacter haemolyticus, sphingomonas paucimobilis, bacillus thuringiensis, staphylo ...201223451394
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 ...201323470772
optimisation of synthesis of oligosaccharides derived from lactulose (fructosyl-galacto-oligosaccharides) with β-galactosidases of different origin.batch synthesis of fructosyl-galacto-oligosaccharides from lactulose was performed with commercial β-galactosidase preparations from aspergillus oryzae, kluyveromyces lactis and bacillus circulans. the enzyme from a. oryzae produced the highest yield and specific productivity of synthesis, being selected for further studies. optimization of fructosyl-galacto-oligosaccharides synthesis was carried out using response surface methodology, considering temperature and initial sugar concentration as v ...201223497880
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 ...201323526073
biodiversity of aerobic endospore-forming bacterial species occurring in yanyanku and ikpiru, fermented seeds of hibiscus sabdariffa used to produce food condiments in benin.yanyanku and ikpiru made by the fermentation of malcavene bean (hibiscus sabdariffa) are used as functional additives for parkia biglobosa seed fermentations in benin. a total of 355 aerobic endospore-forming bacteria (aefb) isolated from yanyanku and ikpiru produced in northern and southern benin were identified using phenotypic and genotypic methods, including gtg5-pcr, m13-pcr, 16s rrna, gyra and gyrb gene sequencing. generally, the same 5-6 species of the genus bacillus predominated: bacillu ...201323571124
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 ...201323578322
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 ...201323694779
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 ...201323725091
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 + ...201323811408
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 ...201323828605
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 ...201323832367
characterization of antifungal activity of the gh-46 subclass iii chitosanase from bacillus circulans mh-k1.we characterized the antifungal activity of the bacillus circulans subclass iii mh-k1 chitosanase (mh-k1 chitosanase), which is one of the most intensively studied glycoside hydrolases (ghs) that belong to gh family 46. mh-k1 chitosanase inhibited the growth of zygomycetes fungi, rhizopus and mucor, even at 10 pmol (0.3 μg)/ml culture probably via its fungistatic effect. the amino acid substitution e37q abolished the antifungal activity of mh-k1 chitosanase, but retained binding to chitotriose. ...201323892828
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 ...201323904990
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 ...201323908050
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.201323965285
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 ...201323968201
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, ...201324024090
biodegradation of naphthalene and anthracene by chemo-tactically active rhizobacteria of populus deltoides.several naphthalene and anthracene degrading bacteria were isolated from rhizosphere of populus deltoides, which were growing in non-contaminated soil. among these, four isolates, i.e. kurthia sp., micrococcus varians, deinococcus radiodurans and bacillus circulans utilized chrysene, benzene, toluene and xylene, in addition to anthracene and naphthalene. kurthia sp and b. circulans showed positive chemotactic response for naphthalene and anthracene. the mean growth rate constant (k) of isolates ...201024031572
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 ...201324048029
kinetic characterization of galacto-oligosaccharide (gos) synthesis by three commercially important β-galactosidases.many β-galactosidases show large differences in galacto-oligosaccharide (gos) production and lactose hydrolysis. in this study, a kinetic model is developed in which the effect of lactose, glucose, galactose, and oligosaccharides on the onpg converting activity of various β-galactosidases is quantified. the use of onpg as a competing substrate to lactose yields more information than can be obtained by examining only the conversion of lactose itself. the reaction rate with lactose or oligosacchar ...201424124064
galactooligosaccharides formation during enzymatic hydrolysis of lactose: towards a prebiotic-enriched milk.the formation of galactooligosaccharides (gos) in skim milk during treatment with several commercial β-galactosidases (bacillus circulans, kluyveromyces lactis and aspergillus oryzae) was analysed in detail, at 4 and 40°c. the maximum gos concentration was obtained at a lactose conversion of approximately 40-50% with b. circulans and a. oryzae β-galactosidases, and at 95% lactose depletion for k. lactis β-galactosidase. using an enzyme dosage of 0.1% (v/v), the maximum gos concentration with k. ...201424128493
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.201324283345
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 ...201224293722
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 ...201424306180
does a rhizospheric microorganism enhance k⁺ availability in agricultural soils?the potassium solubilizing microorganisms (ksms) are a rhizospheric microorganism which solubilizes the insoluble potassium (k) to soluble forms of k for plant growth and yield. k-solubilization is carried out by a large number of saprophytic bacteria (bacillus mucilaginosus, bacillus edaphicus, bacillus circulans, acidothiobacillus ferrooxidans, paenibacillus spp.) and fungal strains (aspergillus spp. and aspergillus terreus). major amounts of k containing minerals (muscovite, orthoclase, bioti ...201424315210
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 ...201424376024
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 ...201424382692
microbial leaching of lateritic nickel ore.lateritic nickel ore from the sukinda mines, orissa, india, was leached using thiobacillus ferrooxidans, bacillus circulans, bacillus licheniformis and aspergillus niger at 5% (w/v) solid: liquid ratio for 5-20 days. maximum leaching of ni was achieved with b. circulans (85%) and aspergillus niger (92%) after 20 days. bacillus circulans showed significantly higher rate of leaching than the other organisms giving 80% ni extraction after 15 days. the importance and usefulness of heterotrophic orga ...199324419960
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.199424421144
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 ...201424458919
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 ...201424463763
efficiency of plant growth-promoting p-solubilizing bacillus circulans cb7 for enhancement of tomato growth under net house conditions.p-solubilizing bacterial isolate cb7 isolated from apple rhizosphere soil of himachal pradesh, india was identified as bacillus circulans on the basis of phenotypic characteristics, biochemical tests, fatty acid methyl esters analysis, and 16s rrna gene sequence. the isolate exhibited plant growth-promoting traits of p-solubilization, auxin, 1-aminocyclopropane-1-carboxylate deaminase activity, siderophore, nitrogenase activity, and antagonistic activity against dematophora necatrix. in vitro st ...201524464353
induction of resistance in tomato plants against tomato mosaic tobamovirus using beneficial microbial isolates.the possibility of making use of the phenome non of systemic acquired resistance (sar) to control viruses achieved by the soaking treatment of tomato seeds cv. castl rock with three growth forms to bacillus circulans, pseudomonas fluorescens 2 and trichoderma harzianum against tomato mosaic tobamovirus (tomv) infection. all the application forms of beneficial biotic inducers were reduced the mean number of tomv local lesions on datura metel. p. fluorescens 2 was found to be the best treatment in ...201324494520
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 ...199824578050
structural elucidation of the cyclization mechanism of α-1,6-glucan by bacillus circulans t-3040 cycloisomaltooligosaccharide glucanotransferase.bacillus circulans t-3040 cycloisomaltooligosaccharide glucanotransferase belongs to the glycoside hydrolase family 66 and catalyzes an intramolecular transglucosylation reaction that produces cycloisomaltooligosaccharides from dextran. the crystal structure of the core fragment from ser-39 to met-738 of b. circulans t-3040 cycloisomaltooligosaccharide glucanotransferase, devoid of its n-terminal signal peptide and c-terminal nonconserved regions, was determined. the structural model contained o ...201424616103
structural basis of a mutant y195i α-cyclodextrin glycosyltransferase with switched product specificity from α-cyclodextrin to β-/γ-cyclodextrin.cyclodextrin glycosyltransferase (ec 2.4.1.19) (cgtase) is an extracellular bacterial enzyme which has the unique capability of forming cyclodextrins from starch. our previous investigation revealed that a mutant y195i α-cgtase drastically altered the cyclodextrin specificity by switching toward the synthesis of both β- and γ-cds (xie et al., 2013a,b). in this study, we determined one x-ray structure of the mutant y195i α-cgtase at 2.3å. the overall structure was similar to that of the typical β ...201424637377
nanosilica sol leads to further increase in polyethylene glycol (peg) 1000-enhanced thermostability of β-cyclodextrin glycosyltransferase from bacillus circulans.a major disadvantage of cyclodextrin production is the limited thermostability of cyclodextrin glycosyltransferase. the ability of combinations of nanosilica sol with polyethylene glycol (peg) 1000 to enhance the thermostability of the β-cyclodextrin glycosyltransferase from bacillus circulans was investigated. it was found that 10% peg 1000 combined with 0.05% nanosilica sol could activate the β-cyclodextrin glycosyltransferase by 17.2%. furthermore, 0.05% nanosilica sol leads to further increa ...201424641510
mutations enhance β-cyclodextrin specificity of cyclodextrin glycosyltransferase from bacillus circulans.the effects of amino acid residue at position 31 in the neighborhood of calcium binding site i (cai) on product specificity of cyclodextrin glycosyltransferase (ec 2.4.1.19, cgtase) were investigated by replacing ala31 in the cgtase from bacillus circulans stb01 with arginine, proline, threonine, serine and glycine. the results showed that the mutations a31r, a31p, and a31t resulted in the increases in β-cyclodextrin-forming activity and β-cyclodextrin production, indicating that these mutations ...201424751254
bacillus mesophilum sp. nov., strain iitr-54t, a novel 4-chlorobiphenyl dechlorinating bacterium.the taxonomic position of a gram-positive, endospore-forming bacterium isolated from soil sample collected from an industrial site was analyzed by a polyphasic approach. the strain designated as iitr-54t matched most of the phenotypic and chemical characteristics of the genus bacillus and represents a novel species. it was found to biodegrade 4-chlorobiphenyl through dechlorination and was isolated through enrichment procedure from an aged polychlorinated biphenyl-contaminated soil. both resting ...201424807729
enhancing the activity of bacillus circulans xylanase by modulating the flexibility of the hinge region.enzymes undergo multiple conformational changes in solution, and these dynamics are considered to play a critical role in enzyme activity. hinge-bending motions, resulting from reciprocal movements of dynamical quasi-rigid bodies, are thought to be related to turnover rate and are affected by the physical properties of the hinge regions. in this study, hinge identification and flexibility modification of the regions by mutagenesis were conducted to explore the relationship between hinge flexibil ...201424849049
polyethylene glycols enhance the thermostability of β-cyclodextrin glycosyltransferase from bacillus circulans.we investigated the ability of six polyethylene glycols (pegs), with molecular weights ranging from 400 to 20,000 da, to enhance the thermostability of β-cyclodextrin glycosyltransferase (β-cgtase) from bacillus circulans. we found that pegs with different molecular weights could activate and stabilize this β-cgtase, but to different degrees. the most significant increase (about 20%) in β-cyclodextrin-forming activity was achieved by adding 10-15% peg 400. pegs with low molecular weights also si ...201424996299
rational design of a glycosynthase by the crystal structure of β-galactosidase from bacillus circulans (bgac) and its use for the synthesis of n-acetyllactosamine type 1 glycan structures.the crystal structure of β-galactosidase from bacillus circulans (bgac) was determined at 1.8å resolution. the overall structure of bgac consists of three distinct domains, which are the catalytic domain with a tim-barrel structure and two all-β domains (abds). the main-chain fold and steric configurations of the acidic and aromatic residues at the active site were very similar to those of streptococcus pneumoniae β(1,3)-galactosidase bgac in complex with galactose. the structure of bgac was use ...201425034434
development of hypoallergenic galacto-oligosaccharides on the basis of allergen analysis.galacto-oligosaccharides (goss) are recognized as prebiotics beneficial to human health through their abilities to modulate gut microbiota. on the other hand, it has been reported that immediate allergic reactions are caused by a gos product (bc-gos) produced by treating lactose with β-galactosidase derived from bacillus circulans. the objective of this study was to create a safer gos product that is less likely to cause gos-induced allergy (gos-al). first, we identified two derivatives of tetra ...201425036491
characterization of a lichenase isolated from soil metagenome.a lichenase gene (mt-lic) was identified for the first time through function-based screening of a soil metagenomic library. its deduced amino acid sequence exhibited a high degree of homology with endo-β-1,3-1,4-glucanase (having both lichenase and chitosanase activities), encoded by the bgc gene of bacillus circulans wl-12. the recombinant lichenase overexpressed and purified from escherichia coli was able to efficiently hydrolyze both barley β-glucan and lichenan. the enzyme showed maximal act ...201425152058
cloning, secretory expression and characterization of recombinant β-mannanase from bacillus circulans nt 6.7.the mannanase gene of b. circulans nt 6.7 was cloned and expressed in an escherichia coli expression system. the b. circulans nt 6.7 mannanase gene consists of 1,083 nucleotides encoding a 360-amino acid residue long polypeptide, belonging to glycoside hydrolase family 26. the full-length mannanase gene including its native signal sequence was cloned into the vector pet21d and expressed in e. coli bl21 (de3). β-mannanase activities in the culture supernatant and crude cell extract were 37.10 and ...201425157333
improvement of chitosan derivatization for the immobilization of bacillus circulans β-galactosidase and its further application in galacto-oligosaccharide synthesis.chitosan was derivatized by two methodologies to design a robust biocatalyst of immobilized bacillus circulans β-galactosidase from a low-cost support for its further application in the synthesis of galacto-oligosaccharides (gos). in the first one, chitosan was derivatized by cross-linking with glutaraldehyde and activated with epichlorohydrin; in the second one, cross-linking and activation were done with epichlorohydrin in a two-step process, favoring first support cross-linking and then suppo ...201425188813
detergent-compatible, organic solvent-tolerant alkaline protease from bacillus circulans mtcc 7942: purification and characterization.proteases are now recognized as the most indispensable industrial biocatalyst owing to their diverse microbial sources and innovative applications. in the present investigation, a thermostable, organic solvent-tolerant, alkaline serine protease from bacillus circulans mtcc 7942, was purified and characterized. the protease was purified to 37-fold by a three-step purification scheme with 39% recovery. the optimum ph and temperature for protease was 10 and 60 °c, respectively. the apparent molecul ...201625356983
mutations in cyclodextrin glycosyltransferase from bacillus circulans enhance β-cyclization activity and β-cyclodextrin production.cyclodextrin glycosyltransferase (ec 2.4.1.19, cgtase) is used to produce cyclodextrins, which are cyclic glucans with many industrial applications. in the present study, the effects of the amino acid residue at position 577, which is located in calcium-binding site iii (caiii), on cyclization activity and cyclodextrin production were investigated by replacing asp577 in cgtase from bacillus circulans stb01 with glutamate, arginine, lysine, and histidine. the results showed that mutations d577e a ...201425359453
production of potent antimicrobial agent by actinomycete, streptomyces sannanensis strain su118 isolated from phoomdi in loktak lake of manipur, india.actinomycetes have provided a wealth of bioactive secondary metabolites with interesting activities such as antimicrobial, antiviral and anticancer. the study aims at isolation, characterization and the antimicrobial potentiality of streptomyces sannanensis su118 obtained from phoomdi, a unique habitat of loktak lake of manipur, india.201425406714
lna-modified isothermal oligonucleotide microarray for differentiating bacilli of similar origin.oligonucleotide microarray has been one of the most powerful tools in the 'post-genome era' for its high sensitivity, high throughput and parallel processing capability. to achieve high detection specificity, we fabricated an isothermal microarray using locked nucleic acid (lna)-modified oligonucleotide probes, since lna has demonstrated the advanced ability to enhance the binding affinity toward their complementary nucleotides. after designing the nucleotide sequences of these oligonucleotide p ...201425431409
(1)h nmr analysis of the lactose/β-galactosidase-derived galacto-oligosaccharide components of vivinal® gos up to dp5.vivinal® gos is a galacto-oligosaccharide (gos) product, prepared from lactose by incubation with bacillus circulans β-galactosidase (ec 3.2.1.23). this complex mixture of saccharides with degree of polymerization (dp) between 1 and 8 is generally applied in infant nutrition. here, a detailed structural description of the commercial product up to the dp5 level is given. first, vivinal® gos was subjected to dp analysis using hplc-sec (rezex rso-01 oligosaccharide ag(+) column) and (1)h nmr analys ...201425444767
biochemical characterization of mutants in the active site residues of the β-galactosidase enzyme of bacillus circulans atcc 31382.the bacillus circulans atcc 31382 β-galactosidase (bgad) is a retaining-type glycosidase of glycoside hydrolase family 2 (gh2). its commercial enzyme preparation, biolacta n5, is used for commercial-scale production of galacto-oligosaccharides (gos). the bgad active site and catalytic amino acid residues have not been studied. using bioinformatic routines we identified two putative catalytic glutamates and two highly conserved active site histidines. the site-directed mutants e447n, e532q, and h ...201425473598
cyclodextrin glycosyltransferase production by free cells of bacillus circulans df 9r in batch fermentation and by immobilized cells in a semi-continuous process.cyclodextrin glycosyltransferase (cgtase) catalyzes starch conversion into cyclic or linear oligosaccharides, important industrial products for the complexation of non-polar substances. in this work, conditions to increase cgtase production from bacillus circulans strain df 9r were optimized by two systems. on one hand, free cells were grown in batch fermentation experiments to optimize aeration and ph. the highest activity (1.47 ± 0.21 u ml(-1)) was achieved after 48 h of growth, aeration of 1. ...201525561345
bacillus species isolated from tungrymbai and bekang, naturally fermented soybean foods of india.tungrymbai and bekang are naturally fermented soybean foods commonly consumed in meghalaya and mizoram states of india. a total of 39 samples of tungrymbai and 43 samples of bekang were collected from different villages and markets of meghalaya and mizoram, respectively and were analysed for microbial load. in both tungrymbai and bekang, the average population of bacillus spp. was 8.2±0.1 log cfu/g. a total of 428 isolates of bacillus were isolated from tungrymbai (211) and bekang (217) for deta ...201525574846
continuous production of cyclodextrins in an ultrafiltration membrane reactor, catalyzed by cyclodextrin glycosyltransferase from bacillus circulans df 9r.cyclodextrins (cds) are cyclic oligosaccharides of wide industrial application, whose synthesis is catalyzed by cyclodextrin glycosyltransferase (cgtase) from starch. here, cds were produced using cgtase from bacillus circulans df 9r in continuous process and an ultrafiltration membrane reactor. the batch process was conducted as a control. this method allowed increasing the yield from 40 to 55.6% and the productivity from 26.1 to 99.5 mg of cd per unit of enzyme. the method also allowed obtaini ...201525583301
epimerization at c-3'' in butirosin biosynthesis by an nad(+) -dependent dehydrogenase btre and an nadph-dependent reductase btrf.butirosin is an aminoglycoside antibiotic consisting two epimers at c-3'' of ribostamycin/xylostasin with a unique 4-amino-2-hydroxybutyrate moiety at c-1 of the aminocyclitol 2-deoxystreptamine (2dos). to date, most of the enzymes encoded in the biosynthetic gene cluster for butirosin, from the producing strain bacillus circulans, have been characterized. a few unknown functional proteins, including nicotinamide adenine dinucleotide cofactor-dependent dehydrogenase/reductase (btre and btrf), ar ...201525600434
molecular engineering of cycloisomaltooligosaccharide glucanotransferase from bacillus circulans t-3040: structural determinants for the reaction product size and reactivity.cycloisomaltooligosaccharide glucanotransferase (citase) is a member of glycoside hydrolase family 66 and it produces cycloisomaltooligosaccharides (cis). small cis (ci-7-9) and large cis (ci-≥10) are designated as oligosaccharide-type cis (oligo-cis) and megalosaccharide-type cis (megalo-cis) respectively. citase from bacillus circulans t-3040 (bccitase) produces mainly ci-8 with little megalo-cis. it has two family 35 carbohydrate-binding modules (bccbm35-1 and bccbm35-2). bccbm35-1 is inserte ...201525649478
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