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1.
A thermostable chitosanase gene from the environmental isolate Bacillus sp. strain CK4, which was identified on the basis of phylogenetic analysis of the 16S rRNA gene sequence and phenotypic analysis, was cloned, and its complete DNA sequence was determined. The thermostable chitosanase gene was composed of an 822-bp open reading frame which encodes a protein of 242 amino acids and a signal peptide corresponding to a 30-kDa enzyme. The deduced amino acid sequence of the chitosanase from Bacillus sp. strain CK4 exhibits 76.6, 15.3, and 14.2% similarities to those from Bacillus subtilis, Bacillus ehemensis, and Bacillus circulans, respectively. C-terminal homology analysis shows that Bacillus sp. strain CK4 belongs to cluster III with B. subtilis. The gene was similar in size to that of the mesophile B. subtilis but showed a higher preference for codons ending in G or C. The enzyme contains 2 additional cysteine residues at positions 49 and 211. The recombinant chitosanase has been purified to homogeneity by using only two steps with column chromatography. The half-life of the enzyme was 90 min at 80°C, which indicates its usefulness for industrial applications. The enzyme had a useful reactivity and a high specific activity for producing functional oligosaccharides as well, with trimers through hexamers as the major products.  相似文献   

2.
Forty-one open reading frames (ORFs) were identified in a 32-kb DNA fragment of alkaliphilic Bacillus sp. C-125. A similarity search using the BSORF database found 37 ORFs with significant sequence similarity to B. subtilis RNA polymerase subunits, elongation factor G, elongation factor Tu, and ribosomal proteins. Each ORF product showed more than 70% identity to those of B. subtilis. Gene organization in the region of str, S10, spc, and the α cluster was highly conserved among three strains, C-125, B. subtilis, and B. stearothermophilus.  相似文献   

3.
Two types of white wheat bread (high- and low-type loaves) were investigated for rope spoilage. Thirty of the 56 breads tested developed rope spoilage within 5 days; the high-type loaves were affected by rope spoilage more than the low-type loaves. Sixty-one Bacillus strains were isolated from ropy breads and were characterized on the basis of their phenotypic and genotypic traits. All of the isolates were identified as Bacillus subtilis by biochemical tests, but molecular assays (randomly amplified polymorphic DNA PCR assay, denaturing gradient gel electrophoresis analysis, and sequencing of the V3 region of 16S ribosomal DNA) revealed greater Bacillus species variety in ropy breads. In fact, besides strains of B. subtilis, Bacillus licheniformis, Bacillus cereus, and isolates of Bacillus clausii and Bacillus firmus were also identified. All of the ropy Bacillus isolates exhibited amylase activity, whereas only 32.4% of these isolates were able to produce ropiness in bread slices after treatment at 96°C for 10 min. Strains of lactic acid bacteria previously isolated from sourdough were first selected for antirope activity on bread slices and then used as starters for bread-making experiments. Prevention of growth of approximately 104 rope-producing B. subtilis G1 spores per cm2 on bread slices for more than 15 days was observed when heat-treated cultures of Lactobacillus plantarum E5 and Leuconostoc mesenteroides A27 were added. Growth of B. subtilis G1 occurred after 7 days in breads started with Saccharomyces cerevisiae T22, L. plantarum E5, and L. mesenteroides A27.  相似文献   

4.
The nucleotide sequences of three independent fragments (designated no. 3, 4, and 9; each 15–20 kb in size) of the genome of alkaliphilic Bacillus sp. C-125 cloned in a λ phage vector have been determined. Thirteen putative open reading frames (ORFs) were identified in sequenced fragment no. 3 and 11 ORFs were identified in no. 4. Twenty ORFs were also identified in fragment no. 9. All putative ORFs were analyzed in comparison with the BSORF database and non-redundant protein databases. The functions of 5 ORFs in fragment no. 3 and 3 ORFs in fragment no. 4 were suggested by their significant similarities to known proteins in the database. Among the 20 ORFs in fragment no. 9, the functions of 11 ORFs were similarly suggested. Most of the annotated ORFs in the DNA fragments of the genome of alkaliphilic Bacillus sp. C-125 were conserved in the Bacillus subtilis genome. The organization of ORFs in the genome of strain C-125 was found to differ from the order of genes in the chromosome of B. subtilis, although some gene clusters (ydh, yqi, yer, and yts) were conserved as operon units the same as in B. subtilis. Received: April 17, 1998 / Accepted: June 23, 1998  相似文献   

5.
A rod shaped, non-motile, endospore forming, Gram-stain positive and moderately halotolerant strain, designated as NCCP-168T, was isolated from salt mines sampled in the Karak district of Khyber Pakhtunkhwa Province in Pakistan. To delineate its taxonomic position, the strain was subjected to polyphasic characterization. Cells of strain NCCP-168T can grow at 10–40 C (optimum at 30–35 C), in a pH range of 5.0–9.0 (optimum at pH 8.0) and in 0–17 % (w/v) NaCl on agar medium. The phylogenetic analysis based on the 16S rRNA gene sequence showed that strain NCCP-168T belongs to the genus Bacillus with the highest similarity to Bacillus seohaeanensis BH724T (97.1 %), and less than 97 % similarity with other closely related taxa (95.6 % with B. subtilis subsp. subtilis NCIB3610T). DNA–DNA relatedness between strain NCCP-168T and the type strains of closely related species was lower than 30 %. Chemotaxonomic data (major menaquinone, MK-7; cell wall peptidoglycan type, A1γ [meso-diaminopimelic acid]; major fatty acids, iso-C15:0 29.9 %, anteiso-C15:0 29.3 %, iso-C16:0 11.4 %, iso-C14:0 8.9 % and anteiso-C17:0 7.0 %; major polar lipids, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine) support the affiliation of strain NCCP-168T with genus Bacillus. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain NCCP-168T can be distinguished from the closely related taxa and thus represents a novel species in the genus Bacillus, for which the name Bacillus pakistanensis sp. nov. is proposed, with the type strain NCCP-168T (= KCTC 13786T = DSM 24834T = JCM 18975T).  相似文献   

6.
A Bacillus spp. strain isolated from a honey sample in Morillos (Salta, Argentina) was phylogenetically characterized as B. subtilis subsp. subtilis Mori2. The strain was administered to bee colonies as a monoculture in one litre of sugarcane syrup (125?g/L) at a final concentration of 105?spores/mL to evaluate the bee colony performance. The treated colony was monitored, and any changes were compared with the control hives. All conditions were identical (weather, nourishment and supervision), except for the Bacillus spore supplement. The new nourishment, which was administered monthly from May to December 2010, was accepted by the bees and consumed within ca. 24?C48?h. Photograph records and statistic analyses revealed significant differences in the open and operculated brood areas between the treated and control groups. The status of the colony improved after the second administration of the Bacillus spores until the end of the experiment. A higher number of bees were counted in the treated groups (26% more than the control) with respect to the initial number. Furthermore, at the time of harvest, honey storage in the treated hives was 17% higher than in the control hives. In addition, spore counts of both Nosema sp. and Varroa sp. foretica in treated hives were lower than in the control hives. These results with experimental hives would indicate that B. subtilis subsp. subtilis Mori2 favoured the performance of bees; firstly, because the micro-organism stimulated the queen??s egg laying, translating into a higher number of bees and consequently more honey. Secondly, because it reduced the prevalence of two important bee diseases worldwide: nosemosis and varroosis.  相似文献   

7.
A Bacillus-like isolate, strain FJAT-13831T, isolated from the No. 1 pit soil of Emperor Qin’s Terra-cotta Warriors in Xi’an City, China, was studied to determine its taxonomic status. Dominant fatty acids of this organism included iso-C15:0, iso-C17:0, C16:0, iso-C13:0, anteiso-C15:0, and iso-C17:1ω5c. Comparative 16S rRNA gene sequence analysis confirmed the affiliation of this isolate to the genus Bacillus and indicated that it was closely related to Bacillus pseudomycoides DSM 12442T (99.72 % similarity). A phylogenetic analysis of the gyrB gene sequence similarities exhibited independent clustering of the isolate FJAT-13831T and showed 93.8 % (<95 %) sequence similarity with its closest phylogenetic neighbour B. pseudomycoides DSM 12442T. Separate standing of the strain FJAT-13831T was supported by a whole genome-based phylogenetic analysis with an average nucleotide identity value of 91.47 (<95 %) between isolate FJAT-13831T and B. pseudomycoides DSM 12442T and was consistent with the results of DNA–DNA hybridization (69.1 % relatedness). These findings support the conclusion that the isolate FJAT-13831T represents a novel species, for which the name Bacillus bingmayongensis sp. nov. is proposed. The type strain is FJAT-13831T (= CGMCC 1.12043T = DSM 25427T).  相似文献   

8.
A novel bacterial strain, designated PFS-5T, was isolated from the soil environment with feces of a live poultry farm located in Cheonan, Republic of Korea. Strain PFS-5T was Gram-staining-positive, motile, strictly aerobic bacterium, rod-shaped, and endospore-forming. The strain contained meso-diaminopimelic acid in their peptidoglycan and MK-7 menaquinone. The major fatty acids were anteiso-C15:0 (44.2%), C16:0 (22.2%), and iso-C15:0 (16.7%). The DNA G+C content was 40.1 mol%. Comparative 16S rRNA gene sequence analysis identified strain PFS-5T in the genus Bacillus, exhibiting the highest level of sequence similarity with type strain of B. herbersteinensis D-1,5aT (96.9%), B. humi LMG 22167T (96.7%), B. alkalitelluris BA288T (96.1%), B. litoralis SW-211T (96.0%), and B. luteolus YIM93174T (95.5%). The major polar lipids of PFS-5T were diphosphatidylglycerol and phosphatidylglycerol. On the basis of result from poly-phasic data, strain PFS-5T represents a novel species, for which the name Bacillus cheonanensis sp. nov. is proposed (Type strai PFS-5T = KACC 17469T = JCM19333T).  相似文献   

9.
A novel Gram-stain-positive, slightly halophilic, catalase- and oxidase-positive, endospore-forming, motile, aerobic, rod-shaped bacterium, designated strain JSM 081003T, was isolated from non-saline forest soil in Hunan Province, China. Growth occurred with 0.5?C15% (w/v) NaCl (optimum 2?C4%) at pH 6.5?C10.5 (optimum pH 7.5?C8.5) and at 5?C40°C (optimum 30°C). meso-Diaminopimelic acid was present in the cell-wall peptidoglycan. The major cellular fatty acids were iso-C15:0, anteiso-C15:0 and iso-C14:0. Strain JSM 081003T contained MK-7 as the predominant respiratory quinone, and diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol as the major polar lipids. The genomic DNA G + C content of strain JSM 081003T was 40.9 mol%. A phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain JSM 081003T should be assigned to the genus Bacillus, and was related most closely to the type strains of Bacillus lehensis (sequence similarity 99.6%), Bacillus oshimensis (99.4%) and Bacillus patagoniensis (96.6%); lower than 96.0% sequence similarity was observed with other Bacillus species. The combination of phylogenetic analysis, DNA?CDNA relatedness values, phenotypic characteristics and chemotaxonomic data supports the view that strain JSM 081003T represents a new species of the genus Bacillus, for which the name Bacillus hunanensis sp. nov. is proposed. The type strain is JSM 081003T (= DSM 23008T = KCTC 13711T).  相似文献   

10.
Using a new culture method for unculturable soil bacteria, we discovered a novel species, NHI-38T, from the forest soil of Kyonggi University campus, South Korea. It was a Gram-positive, rod-shaped, and endospore-forming bacterial strain. It grew over a wide pH range (6.5–9.5), with an optimum range of pH 7–9, and in a wide range of temperatures (15–60 °C), with an optimum range of 35–45 °C. Growth was possible at 0–2 % NaCl concentration, and the optimal range was between 0.5 and 1.5 % NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that this new species clustered within the genus Bacillus; it was closely related to “Bacillus abyssalis” SCSIO 15042T (98.86 %), B. methanolicus NCIMB 13113T (95.97 %), B. vietnamensis 15-1T (95.8 %), B. seohaeanensis BH724T (95.5 %), B. timonensis MM10403188T (95.33 %), and B. subtilis subsp. subtilis NCIB 3610T (94.87 %). The main fatty acid components of this bacterium were iso-C15:0 (35.92 %), summed feature 3 (C16:1ω7c/C16:1ω6c; 16.92 %), and anteiso-C15:0 (14.19 %). The predominant quinone in this bacterial strain was MK-7. The polar lipid profile primarily comprised phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. The genomic DNA G+C composition of the isolate was 40.7 mol%. The DNA–DNA hybridization results indicated that this strain was distinct from other Bacillus species, the degree of similarity being 50 % with “B. abyssalis”, 56 % with B. methanolicus, 47 % with B. vietnamensis, 43 % with B. seohaeanensis, 46 % with B. timonensis, and 32 % with B. subtilis. Based on our results, we regard strain NHI-38T as a novel member of the Bacillus genus, and we propose the name Bacillus thaonhiensis (=KACC 17216T = KEMB 9005-019T = JCM 18863T).  相似文献   

11.
R.M. Simmons 《FEBS letters》1983,164(1):201-204
On incubation of B. subtilis RM125(arg15 leuA8 rM? mM?) with DNA from alkalophilic Bacillus, the transformants (Arg+Leu? or Leu?Arg+) appeared at pH 10. The transformants were able to grow even at pH 7. Alkalophilic Bacillus was resistant to bacteriophages π105D1C2·1012 grown on B. subtilis 1012(r-mM+) and π105D1C2·ISMR4 grown on B. subtilis ISMR4rM+rR+mM+mR+), but the recipient B. subtilis and the transformant(Arg+Leu?) were susceptible to both the of the bacteriophages. The results indicate that the transformant is a B. subtilis derivative and that alkalophilicity of alkalophilic Bacillus was transferred to B. subtilis.  相似文献   

12.
A bacterial strain, designated CY22, was isolated from the interior of balloon flower (Platycodon grandiflorum) root in the Republic of Korea. The isolate coproduced an iturin-like antifungal compound and a surfactin-like potent biosurfactant. Analysis of the 16S-rDNA of strain CY22 showed that the isolate was a member of Bacillus. High similarities were observed between strain CY22 and Bacillus sp. TKSP 24, and between strain CY22 and B. subtilis 168. Phylogenetic analysis based on 16S-rDNA sequences showed that strain CY22 was closely related to Bacillus sp. The main whole-cell fatty acids were anteiso-C15:0 (37%), C17:0 (5.1%), and iso-C15:0 (27.7%). DNA G + C content was 54 mol%. Based on phylogenetic inference, phenotypic and chemotaxonomic characteristics, this endophytic strain Bacillus sp. CY22 was assigned to the genus Bacillus.  相似文献   

13.
Flagellin glycosylation was identified in Bacillus sp. PS3 and Geobacillus stearothermophilus. In vivo complementation showed that these flagellin genes did not restore the motility of a Bacillus subtilis flagellin mutant, whereas the genes encoding non-glycosylated flagellin from Geobacillus kaustophilus and Bacillus sp. Kps3 restored motility. Moreover, four types of flagellins expressed in B. subtilis were not glycosylated. We speculate that glycosylation is required for flagellar filament assembly of these bacilli.  相似文献   

14.
1-Deoxynojirimycin (DNJ), a D-glucose analogue with a nitrogen atom substituting for the ring oxygen, is a strong inhibitor of intestinal α-glucosidase. DNJ has several promising biological activities, including its antidiabetic, antitumor, and antiviral activities. Nevertheless, only limited amounts of DNJ are available because it can only be extracted from some higher plants, including the mulberry tree, or purified from the culture broth of several types of soil bacteria, such as Streptomyces sp. and Bacillus sp. In our previous study, a DNJ-producing bacterium, Bacillus subtilis MORI, was isolated from the traditional Korean fermented food Chungkookjang. In the present study, we report the identification of the DNJ biosynthetic genes in B. subtilis MORI 3K-85 strain, a DNJ-overproducing derivate of the B. subtilis MORI strain generated by γ-irradiation, xhe genomic DNA library of B. subtilis MORI 3K-85 was constructed in Escherichia coli, and clones showing α-glucosidase inhibition activity were selected. After DNA sequencing and a series of subcloning, we were able to identify a putative Operon which consists of gabT1, yktc1, and gutB1 genes predicted to encode putative transaminase, phosphatase, and oxidoreductase, respectively. When a recombinant plasmid containing this Operon sequence was transformed into an E. coli strain, the resulting transformant was able to produce DNJ into the culture medium. Our results indicate that the gabT1, yktc1, and gutB1 genes are involved in the DNJ biosynthetic pathway in B. subtilis MORI, suggesting the possibility of employing these genes to establish a large-scale microbial DNJ overproduction system through genetic engineering and process optimization.  相似文献   

15.
The xynA gene encoding a xylanase from the recently isolated Bacillus sp. strain BP-7 has been cloned and expressed in Escherichia coli. Recombinant xylanase A showed high activity on xylans from hardwoods and cereals, and exhibited maximum activity at pH 6 and 60°C. The enzyme remained stable after incubation at 50°C and pH 7 for 3 h, and it was strongly inhibited by Mn2+, Fe3+, Pb2+, and Hg2+. Analysis of xylanase A in zymograms showed an apparent molecular size of 24 kDa and a pI of above 9. The amino acid sequence of xylanase A, as deduced from xynA gene, shows homology to alkaline pI-low molecular weight xylanases of family 11 such as XynA from Bacillus subtilis. Analysis of codon usage in xynA from Bacillus sp. BP-7 shows that the G+C content at the first and second codon positions is notably different from the mean values found for glycosyl hydrolase genes from Bacillus subtilis.  相似文献   

16.
A taxonomic study was carried out on strain HYC-10T, which was isolated from the intestinal tract contents of a flathead mullet, Mugil cephalus, captured from the sea off Xiamen Island, China. The bacterium was observed to be Gram positive, oxidase and catalase positive, rod shaped, and motile by subpolar flagella. The bacterium was found to grow at salinities of 0–12 % and at temperatures of 8–45 °C. The isolate was found to hydrolyze aesculin and gelatin, but was unable to reduce nitrate to nitrite. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HYC-10T belongs to the genus Bacillus, with highest sequence similarity (99.3 %) to Bacillus aerophilus 28KT, Bacillus stratosphericus 41KF2aT and Bacillus altitudinis DSM 21631T, followed by Bacillus safensis DSM 19292T (99.5 %) and Bacillus pumilus DSM 27T (99.5 %), while the sequence similarities to others were all below 97.6 %. The genomic ANIm values between strain HYC-10T and three type strains (B. altitudinis DSM 21631T, B. safensis DSM 19292T and B. pumilus DSM 27T) were determined to range from 89.11 to 91.53 %. The DNA–DNA hybridization estimate values between strain HYC-10T and the three type strains were from 36.60 to 44.00 %. The principal fatty acids identified were iso-C15:0 (39.1 %), anteiso-C15:0 (22.7 %), iso-C17:0 (13.1 %), C16:0 (6.1 %), anteiso-C17:0 (5.8 %) and iso-C16:0 (5.1 %). The G+C content of the chromosomal DNA was determined from the draft genome sequence to be 41.3 mol%. The respiratory quinone was determined to be MK-7 (100 %). Phosphatidylglycerol, diphosphatidylglycerol, aminoglycolipid, two glycolipids and two unknown phospholipids were found to be present. The combined genotypic and phenotypic data show that strain HYC-10T represents a novel species of the genus Bacillus, for which the name Bacillus xiamenensis sp. nov. is proposed, with the type strain HYC-10T (=CGMCC NO.1.12326T = LMG 27143T = MCCC 1A00008T).  相似文献   

17.
Bacillus sp. PS3 produces a glycosylated flagellin. In this study, a number of the glycosylated residues of the flagellin protein were found to be located in the central variable region of this protein. We also report that the motility defect of the Bacillus subtilis flagellin mutant was complemented by Bacillus sp. PS3 flagellin variants without glycosylation, which contained amino acid substitutions and intragenic duplications in the variable region of flagellin.  相似文献   

18.
To produce xylobiose from xylan, high-level expression of an endoxylanase gene from Bacillus sp. was carried out in Bacillus subtilis DB104. A 1.62-kb SmaI DNA fragment, coding for an endoxylanase of Bacillus sp., was ligated into the Escherichia coli/B. subtilis shuttle vector pJH27Δ88, producing pJHKJ4, which was subsequently transformed into B. subtilis DB104. A maximum endoxylanase activity of 105 U/ml was obtained from the supernatant of B. subtilis DB104 harboring pJHKJ4. The endoxylanase was purified to homogeneity by ion-exchange chromatography and the production profile of xylooligosaccharides from xylan by the endoxylanase was examined by HPLC with a carbohydrate analysis column. Xylobiose was the major product from xylan at 40 °C and its proportion in the xylan hydrolyzates increased with the reaction time; at 12 h, over 60% of the reaction products was xylobiose. These results suggest that xylobiose, which has a stimulatory effect on the selective growth of the intestinal bacterium Bifidobacterium, can be mass-produced effectively by the endoxylanase of Bacillus sp. cloned in B. subtilis. Received: 2 January 1998 / Received revision: 4 March 1998 / Accepted: 4 March 1998  相似文献   

19.
Bacillus subtilis strain 168 is known to possess two genes that encode thymidylate synthases, thyA and thyB. We have identified genes similar to the thyA and thyB genes in several Bacillus strains by Southern hybridization and by DNA amplification with sequence-specific primers. Analysis of thyA genes cloned from B. subtilis W23 strain 2A6, B. subtilis ATCC6633, B. amyloliquefaciens S18 and B. atrophaeus S223 reveals that they are very similar to the thyA genes from B. subtilis 168 and its phage φ3T, but differ considerably from the majority of known prokaryotic and eukaryotic thymidylate synthases.  相似文献   

20.
Lantibiotics are small peptide antibiotics that contain the characteristic thioether amino acids lanthionine and methyllanthionine. As ribosomally synthesized peptides, lantibiotics possess biosynthetic gene clusters which contain the structural gene (lanA) as well as the other genes which are involved in lantibiotic modification (lanM, lanB, lanC, lanP), regulation (lanR, lanK), export (lanT(P)) and immunity (lanEFG). The lantibiotic mersacidin is produced by Bacillus sp. HIL Y-85,54728, which is not naturally competent.

Methodology/Principal Findings

The aim of these studies was to test if the production of mersacidin could be transferred to a naturally competent Bacillus strain employing genomic DNA of the producer strain. Bacillus amyloliquefaciens FZB42 was chosen for these experiments because it already harbors the mersacidin immunity genes. After transfer of the biosynthetic part of the gene cluster by competence transformation, production of active mersacidin was obtained from a plasmid in trans. Furthermore, comparison of several DNA sequences and biochemical testing of B. amyloliquefaciens FZB42 and B. sp. HIL Y-85,54728 showed that the producer strain of mersacidin is a member of the species B. amyloliquefaciens.

Conclusions/Significance

The lantibiotic mersacidin can be produced in B. amyloliquefaciens FZB42, which is closely related to the wild type producer strain of mersacidin. The new mersacidin producer strain enables us to use the full potential of the biosynthetic gene cluster for genetic manipulation and downstream modification approaches.  相似文献   

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