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1.
The diesel-degrading strains, designated as MJ01 and MJ4, were isolated from oil-contaminated soil in Daejeon (South Korea)
and were taxonomically characterized using a polyphasic approach and their diesel oil degradation abilities were analyzed.
The isolates MJ01 and MJ4 were identified as Acinetobacter haemolyticus and Acinetobacter johnsonii, respectively, based on their 16S rDNA gene sequences, DNA–DNA relatedness, fatty acid profiles and various physiological
characteristics. Strains MJ01 and MJ4 were able to use diesel oil as the sole carbon and energy source. Both strains could
degrade over 90% of diesel oil with an initial concentration of 20,000 mg/l after incubation for 7 days, the most significant
degradation occurred during the first 3 days. To our knowledge, this is the first report on diesel oil-degrading microorganisms
among bacterial strains belonging to A. haemolyticus and A. johnsonii. 相似文献
2.
D. V. Karelov R. A. Kreneva L. Errais Lopes D. A. Perumov A. S. Mironov 《Russian Journal of Genetics》2011,47(6):757-761
The nucleotide sequence of the ribC gene encoding the synthesis of bifunctional flavokinase/flavine adenine nucleotide (FAD) synthetase in Bacillus subtilis have been determined in a family of riboflavinconstitutive mutants. Two mutations have been found in the proximal region
of the gene, which controls the transferase (FAD synthase) activity. Three point mutations and one double mutation have been
found (in addition to the two mutations that were detected earlier) in the distal region of the gene, which controls the flavokinase
(flavin mononucleotide (FMN) synthase) activity. On the basis of all data known to date, it has been concluded that the identified
mutations affect riboflavin and ATP binding sites. No mutations have been found in the PTAN conserved sequence, which forms
the magnesium and ATP common binding site and is identical for organisms of all organizational levels, from bacteria too humans. 相似文献
3.
4.
Sevdalina Todorova Lubka Kozhuharova 《World journal of microbiology & biotechnology》2010,26(7):1207-1216
Antagonistic Bacillus strains were isolated from soil and analyzed for the purpose of determining whether they could be used as natural biological
agents. Primary in vitro screening for antagonism of the isolates was performed against five phytopathogenic mould fungi.
Strains TS 01 and ZR 02 exhibited the most pronounced inhibitory effects. They were identified as Bacillus subtilis on the basis of their morphological, cultural and physiology-biochemical properties as well as their hierarchical cluster
analysis conducted by means of computer program SPSS. The antimicrobial activity of the strains from cultural medium and sterile
filtrate were determined in vitro against a great number of predominantly phytopathogenic fungi and bacteria. TS 01 and ZR
02 strains exhibited very broad and at the same time degree varying antibiotic spectra of activities against both Gram-positive
and Gram-negative microorganisms. Many of them were tested against sensitivity to the antimicrobial action of B. subtilis for the very first time. B. subtilis TS 01 and ZR 02 showed highest antifungal activity (sterile zone in diameter over 37 mm) against Alternaria solani, Botrytis cinerea, Monilia linhartiana 869, Phytophthora cryptogea 759/1 and Rhizoctonia sp. The most sensitive bacterial species were found to be Pseudomonas syringae pv. tomato Ro and Xanthomonas campestris with sterile zones 48.0 and 50.0 mm in diameter, respectively. The latter draws a conclusion that the isolated and identified
Bacillus subtilis strains are promising natural biocontrol agents and should be further studied and tested for control of numerous plant diseases. 相似文献
5.
Chemotaxis is a process in which bacteria sense their chemical environment and move towards more favorable conditions. Since
plant colonization by bacteria is a multifaceted process which requires a response to the complex chemical environment, a
finely tuned and sensitive chemotaxis system is needed. Members of the Bacillus subtilis group including Bacillus amyloliquefaciens are industrially important, for example, as bio-pesticides. The group exhibits plant growth-promoting characteristics, with
different specificity towards certain host plants. Therefore, we hypothesize that while the principal molecular mechanisms
of bacterial chemotaxis may be conserved, the bacterial chemotaxis system may need an evolutionary tweaking to adapt it to
specific requirements, particularly in the process of evolution of free-living soil organisms, towards plant colonization
behaviour. To date, almost nothing is known about what parts of the chemotaxis proteins are subjected to positive amino acid
substitutions, involved in adjusting the chemotaxis system of bacteria during speciation. In this novel study, positively
selected and purified sites of chemotaxis proteins were calculated, and these residues were mapped onto homology models that
were built for the chemotaxis proteins, in an attempt to understand the spatial evolution of the chemotaxis proteins. Various
positively selected amino acids were identified in semi-conserved regions of the proteins away from the known active sites. 相似文献
6.
7.
Pazlarova J 《Journal of industrial microbiology & biotechnology》2010,37(12):1257-1261
Anomalous forms of Bacillus subtilis A32 produced by prolonged cultivation in a chemostat under nitrogen limitation are described. A change in the cultivation
conditions brought about a transformation of these forms to bacillar rods. The transformation was gradual and lasted for several
generations. 相似文献
8.
Natural wild-type strains of Bacillus subtilis spore is regarded as a non-pathogenic for both human and animal, and has been classified as a novel food which is currently
being used as probiotics added in the consumption. To identify B. subtilis spore proteins, we have accomplished a preliminary proteomic analysis of B. subtilis spore, with a combination of two-dimensional electrophoretic separations and matrix-assisted laser desorption ionization
tandem time of flight mass spectrometry (MALDI–TOF–MS). In this article, we presented a reference map of 158 B. subtilis spore proteins with an isoelectric point (pI) between 4 and 7. Followed by mass spectrometry (MS) analysis, we identified
71 B. subtilis spore proteins with high level of confidence. Database searches, combined with hydropathy analysis and GO analysis revealed
that most of the B. subtilis spore proteins were hydrophilic proteins related to catalytic function. These results should accelerate efforts to understand
the resistance of spore to harsh conditions. 相似文献
9.
Bacillus subtilis strain IB exhibiting inhibitory activity against the Fusarium head blight disease fungus Fusarium graminearum was isolated and identified. The major inhibitory compound was purified from the culture broth through anion exchange, hydrophobic
interaction, and reverse phase high-performance liquid chromatography (RP-HPLC) steps. It was a 1,463-Da lipopeptide and had
an amino acid composition consisting of Ala, Glx, Ile, Orn, Pro, Thr, and Tyr at a molar ratio of 1:3:1:1:1:1:2. Electrospray
ionization mass spectrometry/mass spectrometry (ESI MS/MS) analyses of the natural and the ring-opened peptides showed the
antagonist was fengycin, a kind of macrolactone molecule with antifungal activity produced by several Bacillus strains. Fluorescence microscopic analysis indicated this peptide permeabilized and disrupted F. graminearum hyphae. 相似文献
10.
Sharipova MR Shagimardanova EI Chastukhina IB Shamsutdinov TR Balaban NP Mardanova AM Rudenskaya GN Demidyuk IV Kostrov SV 《Molecular biology reports》2007,34(2):79-87
The gene encoding for B. intermedius glutamyl endopeptidase (gseBi) has previously been cloned and its nucleotide sequence analyzed. In this study, the expression of this gene was explored
in protease-deficient strain B. subtilis AJ73 during stationary phase of bacterial growth. We found that catabolite repression usually involved in control of endopeptidase
expression during vegetative growth was not efficient at the late stationary phase. Testing of B. intermedius glutamyl endopeptidase gene expression with B. subtilis spo0-mutants revealed slight effect of these mutations on endopeptidase expression. Activity of glutamyl endopeptidase was
partly left in B. subtilis ger-mutants. Probably, gseBi expression was not connected with sporulation. This enzyme might be involved in outgrowth of the spore, when germinating
endospore converts into the vegetative cell. These data suggest complex regulation of B. intermedius glutamyl endopeptidase gene expression with contribution of several regulatory systems and demonstrate changes in control
of enzyme biosynthesis at different stages of growth. 相似文献
11.
E. U. Poluektova E. Yu. Gagarina V. Z. Nezametdinova I. P. Chilovskii S. A. Rodionova A. A. Prozorov 《Russian Journal of Genetics》2010,46(1):26-35
The nucleotide sequences of three DNA fragments (total size 30574 bp) of the plasmid p19 from the Bacillus subtilis 19 soil strain have been determined. Thirty open reading frames (ORFs) have been identified in these fragments. oriT of the plasmid has also been identified. As shown by the search for homologs of hypothetical protein products of these ORFs
in databases, such homology exists for 18 ORFs. The protein products of nine ORFs can be assumed to have specific functions.
Several ORFs were inactivated via insertional mutagenesis, and the conjugation capacity of the mutant plasmids was estimated.
According to the data on homology of protein products and the results of ORF inactivation, regions of a total size of about
20 kb from the DNA fragments sequenced by us were inferred to belong to the tra region of p19. As follows from the analysis of the identified ORFs of the p19 tra region, it differs from the earlier described tra regions of other plasmids, irrespective of a certain similarity with the corresponding regions of plasmids of gram-positive
bacteria from the genera Bacillus, Clostridium, and Listeria. 相似文献
12.
13.
Joong-Chul Lee Jeong-Heon Cha Dennis B. Zerbv George C. Stewart 《Current microbiology》2003,47(2):0146-0152
The divIVB operon of Bacillus subtilis includes the cell shape-associated mre genes, including the membrane-associated proteins MreC and MreD. TnphoA mutagenesis was utilized to analyze a topological model for MreC. MreC has a short cytoplasmic amino terminus, a single membrane-spanning domain, and a large carboxy terminal domain which lies externally to the outer leaflet of the cell membrane. Expression of the B. subtilis MreB protein, or the Mre C and D proteins, results in a morphological conversion of the Escherichia coli host cells from a rod to a roughly spherical cell, morphologically similar to mre-negative mutants of E. coli. Immunolocalization of the MreC protein in B. subtilis revealed that this protein is found at the midcell division site of the bacterial cells, consistent with the postulated role of the Mre proteins in the regulation of septum-specific peptidoglycan synthesis. RID= ID= <E5>Correspondence to: </E5>G.C. Stewart; <E5>email:</E5> stewart@vet.ksu.edu Received: 5 August 2002 / Accepted: 7 October 2002 相似文献
14.
We assess the microbial assay-dependent effect of AgNP on gram-negative Escherichia coli and gram-positive Bacillus subtilis. The experiment was conducted via three different assays: a growth inhibition assay, a colony forming unit assay, and a liquid-to-plate
assay. AgNP were exposed either as liquid suspensions or in an agar state. Bacterial sensitivity to AgNP was found to be dependent
on the microbial assay employed. E. coli was more sensitive than B. subtilis in the growth inhibition and CFU assays, but B. subtilis was more vulnerable than E. coli in the liquid-to-plate assay, ostensibly owing to the food stress mechanisms of B. subtilis in exposure medium. The dissolution of silver from AgNP could not explain the observed toxicity of AgNP. We detected clear
evidence of AgNP uptake by cells. The results of this study showed that the microbial toxicity of AgNP and the effects of
dissolved silver ions were influenced profoundly by the microbial test method employed. 相似文献
15.
Junehyung Kim 《Biotechnology and Bioprocess Engineering》2017,22(4):462-468
For the enhancement of lipase stability in organic solvent containing reaction, live immobilization method, using Bacillus subtilis spore as a display vehicle was attempted. Bacillus subtilis coat protein cotE was used as an anchoring motif for the display of lipA and lipB of Bacillus subtilis. Using this motif, lipolytic enzyme Lipase A and Lipase B were functionally displayed on the surface of Bacillus subtilis spore. Purified spore displaying CotE-LipB fusion protein showed higher lipolytic activity compared to that of CotE-LipA fusion protein. The surface localization of Lipase B was verified with flow cytometry and protease accessibility experiment. Spore displayed lipase retained its activity against acetone and benzene which completely deactivated free soluble lipase in the same reaction condition. 相似文献
16.
G. F. Khadieva M. T. Lutfullin N. K. Mochalova O. A. Lenina M. R. Sharipova A. M. Mardanova 《Microbiology》2018,87(4):463-471
The properties of new B. subtilis strains GM2 and GM5, isolated from potato rhizosphere and possessing high antimicrobial activity, were studied. The potential of the strains for their use as probiotics was characterized. The strains were resistant to bile and to a wide range of the ambient pH. B. subtilis strains GM2 and GM5 possessed proteolytic and phytate-hydrolyzing activity and proved to be safe for model animals. The strains were characterized by antagonistic properties against phytopathogenic micromycetes, as well as against pathogenic and opportunistic enterobacteria. B. subtilis GM2 and GM5 were concluded to be promising strains for use as probiotics. 相似文献
17.
BIOCHEMICAL studies of chromosome replication have been hampered by the unavailability of an adequate in vitro system with the basic features of in vivo DNA replication. The criteria for such a system are: (1) semiconservative replication; (2) normal biological activity of newly synthesized DNA; (3) normal advancement of the original replication fork; (4) rate of DNA replication equivalent to in vivo; and (5) expected phenotypic behaviour of temperature-sensitive dna mutants. Systems in Escherichia coli, a membrane-DNA fraction1, an agar-embedded cell lysate2 and toluene-treated cells3 have met two or three of the requirements. Several laboratories have also reported the expected behaviour of ts-dna E. coli mutants in toluenized cells3–5. 相似文献
18.
In this study, we explored Bacillus subtilis biofilm growth under various conditions such as the use of substrates with different stiffnesses and nutrient levels using a well-developed optical imaging technique to spatially and temporally track biofilm growth. We also developed a quantitative method to characterize B. subtilis biofilm morphologies under various growth conditions. To determine biofilm rim irregularities, we used the dimensionless P2A ratio, defined as P2/4πA, where P is the perimeter and A is the area of the biofilm. To estimate biofilm thickness from transmission images, we developed a calibration procedure based on Beer- Lambert’s law and cross sectioning. Furthermore, to determine the distributions of different B. subtilis cell phenotypes during biofilm growth, we used a triple-fluorescence-labeled B. subtilis strain that expressed motility, matrix production, and sporulation. Based on this work, we are able to tune biofilm growth by changing its growing environment. 相似文献
19.
Conjugative transfer of 20-kb chromosomal fragment carrying genes encoding tetracycline (tet r ) and lincomycin (lin r ) resistance in the soil strain Bacillus subtilis 19 is described. Transfer was preceded by this fragment insertion into the large conjugative p19cat plasmid producing a hybrid plasmid. Insertion frequency was 10?4?10?5. Then genes tet r and lin r were transferred to the recipient strains. The transfer of chromosomal genes inserted into the plasmid and plasmid gene cat occurred sequentially and resembled sexduction, which represents chromosomal gene transfer by F′ and R′ plasmids during conjugation in Escherichia coli and other gram negative bacteria. 相似文献
20.
Bacillus subtilis, a Gram-positive bacterium commonly found in soil, is an excellent model organism for the study of basic cell processes, such as cell division and cell differentiation, called sporulation. In B. subtilis the essential genetic information is carried on a single circular chromosome, the correct segregation of which is crucial for both vegetative growth and sporulation. The proper completion of life cycle requires each daughter cell to obtain identical genetic information. The consequences of inaccurate chromosome segregation can lead to formation of anucleate cells, cells with two chromosomes, or cells with incomplete chromosomes. Although bacteria miss the classical eukaryotic mitotic apparatus, the chromosome segregation is undeniably an active process tightly connected to other cell processes as DNA replication and compaction. To fully understand the chromosome segregation, it is necessary to study this process in a wider context and to examine the role of different proteins at various cell life cycle stages. The life cycle of B. subtilis is characteristic by its specific cell differentiation process where, two slightly different segregation mechanisms exist, specialized in vegetative growth and in sporulation. 相似文献