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1.
Microbiol Res ; 227: 126297, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421711

RESUMO

Many plant growth promoting rhizobacteria such as Bacillus velezensis GJ11 can produce acetoin to trigger induced systemic resistance (ISR) in plants. For improving acetoin production, the mutant strains were respectively constructed by knockout of the gene of bdh (2,3-butanediol dehydrogenase) and gdh (glycerol dehydrogenase) in GJ11, but only GJ11Δbdh produced a high level of acetoin triggering strong ISR against Pseudomonas syringae infection in plants. GJ11Δbdh could induce H2O2 accumulation in plants by producing a high level of acetoin. H2O2 was necessary for triggering ISR against the pathogen infection because after scavenging H2O2 with ascorbic acid or catalase, the inhibition role to pathogen infection induced by acetoin almost disappeared in plants. Further investigation found the plants treated with GJ11Δbdh in an obvious "priming" state, in which the mild immune response was observed such as a slight increase of H2O2 production, callose deposition, and enzymes activity related with defence response (e.g. POD, PAL and PPO). The plants in "priming" could rapidly respond to the pathogen infection accompanying with a significant increase of H2O2 production, callose deposition, and enzymes activity. Collectively, this study provides new insight into the role of acetoin as a strong elicitor of defense response, and ascribes a new approach to construct the mutant strains with high production of acetoin for triggering stronger ISR against pathogens infection in plants.


Assuntos
Acetoína/metabolismo , Arabidopsis/genética , Bacillus/genética , Bacillus/metabolismo , Resistência à Doença/genética , Imunidade Vegetal/genética , Oxirredutases do Álcool/genética , Arabidopsis/imunologia , Arabidopsis/microbiologia , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Resistência à Doença/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Genes de Plantas/genética , Peróxido de Hidrogênio/metabolismo , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal/fisiologia , Pseudomonas syringae/patogenicidade , Desidrogenase do Álcool de Açúcar/genética
2.
Gene ; 713: 143971, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31299361

RESUMO

An in silico genome analysis of the probiotic Bacillus strain FTC01 was performed. The draft genome comprises 3.9 Mb, with a G + C content of 46.6% and a total of 3941 coding sequences. The species of strain FTC01 was defined as B. velezensis during GenBank genome annotation, following the current nomenclature. Eight gene clusters involved in the synthesis of non-ribosomal lipopeptides, polyketides and bacilysin were found, as well as part of the gene cluster involved in the synthesis of cyclic lipopeptide locillomycin. The production of lipopeptides surfactin and iturin by strain FTC01 was confirmed. In addition, a gene encoding a peptidylprolyl isomerase, involved in bacterial adhesion to the host tissue, beyond twelve genes responsible for acid tolerance and several hydrolase genes were found. These characteristics may help in host colonization and maintenance and may account for the probiotic properties observed for strain FTC01.


Assuntos
Bacillus/genética , Bacillus/metabolismo , Proteínas de Bactérias/genética , Genoma Bacteriano , Metaboloma , Probióticos/metabolismo , Bacillus/crescimento & desenvolvimento , DNA Bacteriano/análise , Filogenia , Análise de Sequência de DNA/métodos
3.
Nat Chem ; 11(7): 653-661, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31182822

RESUMO

Non-ribosomal peptide synthetases (NRPSs) are giant enzyme machines that activate amino acids in an assembly line fashion. As NRPSs are not restricted to the incorporation of the 20 proteinogenic amino acids, their efficient manipulation would enable microbial production of a diverse range of peptides; however, the structural requirements for reprogramming NRPSs to facilitate the production of new peptides are not clear. Here we describe a new fusion point inside the condensation domains of NRPSs that results in the development of the exchange unit condensation domain (XUC) concept, which enables the efficient production of peptides, even containing non-natural amino acids, in yields up to 280 mg l-1. This allows the generation of more specific NRPSs, reducing the number of unwanted peptide derivatives, but also the generation of peptide libraries. The XUC might therefore be suitable for the future optimization of peptide production and the identification of bioactive peptide derivatives for pharmaceutical and other applications.


Assuntos
Peptídeo Sintases/biossíntese , Engenharia de Proteínas/métodos , Aminoácidos/química , Bacillus/genética , Sequência de Bases , Escherichia coli/genética , Família Multigênica , Biblioteca de Peptídeos , Peptídeo Sintases/química , Peptídeo Sintases/genética , Photorhabdus/enzimologia , Domínios Proteicos/genética , Especificidade por Substrato , Xenorhabdus/genética
4.
J Agric Food Chem ; 67(24): 6828-6836, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31136163

RESUMO

Verticillium wilt, caused by Verticillium dahliae, results in a dramatic loss of cotton yields in China. There is great potential for biocontrol to manage this destructive crop disease. In this study, we obtained the endophytic bacterium Bacillus halotolerans Y6 from Verticillium wilt-resistant cotton Gossypium barbadense Xinhai15; this bacterium possesses strong antagonistic abilities that inhibit V. dahliae spore germination and mycelial growth. The results of the enzyme activity assay, heterologous expression, and gene knockdown showed that the key virulence factor of Y6 for antagonizing V. dahliae was ß -glucanase Bgy6. To facilitate field tests of biological control, we constructed the homologous Bgy6-overexpression strain OY6. Compared with the wild-type Y6 strain, the ß-glucanase activity of OY6 was increased by 91.79%, and the inhibition rate of OY6 against V. dahliae V991 exceeded 96.7%. Moreover, the spores of V. dahliae V991 treated with OY6 showed more mucus and larger holes on the surface, as observed by scanning electron microscopy. Potting test results illustrated that both OY6 and Y6 could improve the resistance of upland cotton to Verticillium wilt. With the inoculation of V. dahliae V991 for 45 days, the disease index of G. hirsutum TM-1 treated with OY6 was only 8.33, which was significantly lower than that in plants treated with the wild-type strain Y6 (17.86) or the controls without bacteria (35.94). Our research provides a new idea for the control of Verticillium wilt in upland cotton via transforming endophytic bacteria of Verticillium wilt-resistant cotton and proposes a new solution to prevent and control Verticillium wilt.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias/genética , Endo-1,3(4)-beta-Glucanase/genética , Endófitos/enzimologia , Gossypium/microbiologia , Doenças das Plantas/imunologia , Verticillium/fisiologia , Fatores de Virulência/genética , Antibiose , Bacillus/genética , Bacillus/isolamento & purificação , Bacillus/fisiologia , Proteínas de Bactérias/metabolismo , Resistência à Doença , Endo-1,3(4)-beta-Glucanase/metabolismo , Endófitos/genética , Endófitos/isolamento & purificação , Endófitos/fisiologia , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Gossypium/imunologia , Doenças das Plantas/microbiologia , Fatores de Virulência/imunologia
5.
Mar Drugs ; 17(5)2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31058830

RESUMO

The secondary metabolite Tyrian purple, also known as shellfish purple and royal purple, is a dye with historical importance for humans. The biosynthetic origin of Tyrian purple in Muricidae molluscs is not currently known. A possible role for symbiotic bacteria in the production of tyrindoxyl sulphate, the precursor to Tyrian purple stored in the Australian species, Dicathais orbita, has been proposed. This study aimed to culture bacterial symbionts from the purple producing hypobranchial gland, and screen the isolates for bromoperoxidase genes using molecular methods. The ability of bromoperoxidase positive isolates to produce the brominated indole precursor to Tyrian purple was then established by extraction of the culture, and analysis by liquid chromatography-mass spectrometry (LC-MS). In total, 32 bacterial isolates were cultured from D. orbita hypobranchial glands, using marine agar, marine agar with hypobranchial gland aqueous extracts, blood agar, thiosulphate citrate bile salts sucrose agar, and cetrimide agar at pH 7.2. These included 26 Vibrio spp., two Bacillus spp., one Phaeobacter sp., one Shewanella sp., one Halobacillus sp. and one Pseudoalteromonas sp. The two Bacillus species were the only isolates found to have coding sequences for bromoperoxidase enzymes. LC-MS analysis of the supernatant and cell pellets from the bromoperoxidase producing Bacillus spp. cultured in tryptone broth, supplemented with KBr, confirmed their ability to produce the brominated precursor to Tyrian purple, tyrindoxyl sulphate. This study supports a potential role for symbiotic Bacillus spp. in the biosynthesis of Tyrian purple.


Assuntos
Bacillus/genética , Bactérias/genética , Gastrópodes/microbiologia , Peroxidases/genética , Animais , Bacillus/isolamento & purificação , Bacillus/metabolismo , Bactérias/isolamento & purificação , Bactérias/metabolismo , Região Branquial/metabolismo , Região Branquial/microbiologia , Indóis/análise , Moluscos , Análise de Sequência de RNA , Simbiose
6.
Environ Monit Assess ; 191(5): 314, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31037401

RESUMO

The use of pesticides has been increasing due to the great agricultural production worldwide. The pesticides are used to eradicate pests and weeds; however, these compounds are classified as toxic to non-target organisms. Atrazine and diuron are herbicides widely used to control grassy and broadleaf weeds and weed control in agricultural crops and non-crop areas. Heavy metals are also important environmental contaminants that affect the ecological system. This study aimed to investigate the presence of herbicides-degrading genes and heavy metal resistance genes in bacterial isolates from two different soil samples from two Brazilian regions and to determine the genetic location of these genes. In this study, two isolates were obtained and identified as Escherichia fergusonii and Bacillus sp. Both isolates presented atzA, atzB, atzC, atzD, atzE, atzF, puhA, and copA genes and two plasmids each, being the major with ~ 60 Kb and a smaller with ~ 3.2 Kb. Both isolates presented the atzA-F genes inside the larger plasmid, while the puhA and copA genes were detected in the smaller plasmid. Digestion reactions were performed and showed that the ~ 60-Kb plasmid presented the same restriction profile using different restriction enzymes, suggesting that this plasmid harboring the complete degradation pathway to atrazine was found in both isolates. These results suggest the dispersion of these plasmids and the multi-herbicide degradation potential in both isolates to atrazine and diuron, which are widely used in different culture types worldwide.


Assuntos
Atrazina/metabolismo , Bacillus/genética , Bacillus/metabolismo , Diurona/metabolismo , Escherichia/genética , Escherichia/metabolismo , Herbicidas/metabolismo , Metais Pesados/toxicidade , Plasmídeos/genética , Bacillus/isolamento & purificação , Biodegradação Ambiental , Brasil , Farmacorresistência Bacteriana/genética , Monitoramento Ambiental , Escherichia/isolamento & purificação , Plasmídeos/efeitos dos fármacos , Microbiologia do Solo
7.
World J Microbiol Biotechnol ; 35(6): 83, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31134356

RESUMO

Bacterial metabolites have been observed to be important in new drug formulation for both plant, animals and human beings. The aim of this study was to identify the different bioactive compounds found in three rhizobacterial isolates (B. amyloliquefaciens, B. thuringiensis and Bacillus sp.) from the rhizosphere of Bambara groundnut and to assay for their antibacterial properties. Gas chromatography mass spectrometry (GC-MS) was used to carry out the analysis using seven extraction solvents. In the GC-MS analysis, 68 compounds were identified based on peak area percentage, retention time and structure. From the bioactive compounds in B. amyloliquefaciens and B. thuringiensis, the peak area percentage shows that dimethylfuvene from ethyl acetate extraction had the highest relative abundance with 89.11% while Formic acid 2-methylpropyl ester from hexane extraction had the lowest with 6.25%. Others are tridecane, acetic acid butyl ester, paraldehyde, s-(+)-1,2 propanediol, tropone, phthalan and p-xylene with relative abundance of 61.72%, 60.41%, 83.79%, 71.53%, 24.06%, 86.72% and 64.33% respectively. These extracts inhibited the growth of the four test organisms, Bacillus cereus, Pseudomonas aeruginosa, Micrococcus cryophilus and Enterococcus feacalis. Butanol extract from B. amyloliquefaciens had 28 mm zone of inhibition against B. cereus compared to 18 mm and 16 mm by Bacillus sp. and B. thuringiensis respectively. Its zone of inhibition was 24 mm zone against M. cryophilus compared to 12 mm and 19 mm by Bacillus sp. and B. thuringiensis respectively. Butanol extract from B. thuringiensis suppressed E. feacalis and P. aeruginosa having 23 mm and 26 mm zones of inhibition respectively. This was higher compared to Bacillus sp. and B. amyloliquefaciens having 18 mm/15 mm and 21 mm/15 mm against E. feacalis and P. aeruginosa respectively. Hexane and ethyl acetate extract from Bacillus sp. suppressed P. aeruginosa with 12 mm and 17 mm inhibition zones respectively compared to no inhibition zones from hexane extract of B. amyloliquefaciens and B. thuringiensis. Zones of inhibition of 2 mm and 6 mm were observed against P. aeruginosa from ethyl acetate extract of B. amyloliquefaciens and B. thuringiensis respectively. These results suggest that the three isolates are quite rich in the production of bioactive compounds that are also very effective antibacterial agents. These volatile organic compounds are promising compounds for more antibacterial bioactivity development.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas/métodos , Rhizobium/metabolismo , Vigna/microbiologia , Compostos Orgânicos Voláteis/análise , Bacillus/classificação , Bacillus/genética , Bacillus/isolamento & purificação , Bacillus/metabolismo , Bacillus cereus/efeitos dos fármacos , DNA Ribossômico/genética , Enterococcus faecalis/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Micrococcus/efeitos dos fármacos , Extratos Vegetais/química , Pseudomonas aeruginosa/efeitos dos fármacos , Microbiologia do Solo , África do Sul , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologia
8.
Food Microbiol ; 82: 316-324, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31027789

RESUMO

Biofilm-forming Bacillus species are often involved in contamination of dairy products and therefore present a major microbiological challenge in the field of food quality and safety. In this study, we sequenced and analyzed the genomes of milk- and non-milk-derived Bacillus strains, and evaluated their biofilm-formation potential in milk. Unlike non-dairy Bacillus isolates, the dairy-associated Bacillus strains were characterized by formation of robust submerged and air-liquid interface biofilm (pellicle) during growth in milk. Moreover, genome comparison analysis revealed notable differences in putative biofilm-associated determinants between the dairy and non-dairy Bacillus isolates, which correlated with biofilm phenotype. These results suggest that biofilm formation by Bacillus species might represent a presumable adaptation strategy to the dairy environment.


Assuntos
Adaptação Fisiológica , Bacillus/fisiologia , Biofilmes/crescimento & desenvolvimento , Leite/microbiologia , Adaptação Fisiológica/genética , Animais , Bacillus/classificação , Bacillus/genética , Bacillus/crescimento & desenvolvimento , Análise por Conglomerados , DNA Bacteriano/genética , Microbiologia de Alimentos , Genes Bacterianos/genética , Variação Genética , Genoma Bacteriano/genética , Análise de Sequência de DNA
9.
Appl Microbiol Biotechnol ; 103(10): 4153-4165, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30949808

RESUMO

Bacillus spp. are important producers of bioactive natural products with potential applications in medicine and agriculture. Bacillus sp. SCSIO 05476 from a deep-sea sediment exhibits broad-spectrum antimicrobial activities and strong cytotoxic activity. Here, an integrative approach combining genome mining and metabolic profiling has been applied to decipher the chemical origins of this strain's varied and significant biological activities. First, genome mining revealed 19 candidate gene clusters encoding the biosynthesis of diverse secondary metabolites. Then, a series of bacillibactins, fengycins, bacillomycins, surfactins, bacillaenes, macrolactins, and related species were found by LC-DAD-MS. Finally, three new linear bacillibactins, linbacillibactins A-C (1-3), along with 11 known secondary metabolites, bacillibactin (4), normal-C13 Val7 surfactin (5), anteiso-C13 Leu7 surfactin (6), iso-C14 Leu7 surfactin (7), normal-C14 Leu7 surfactin (8), anteiso-C14 Leu7 surfactin (9), macrolactin D (10), normal-C14 bacillomycin D (11), iso-C16 bacillomycin D (12), normal-C17 bacillomycin D (13), and iso-C17 bacillomycin D (14), were obtained and elucidated by bioactivity and structure-guided isolation from the fermentation of strain SCSIO 05746. Among them, new compounds 1-3 show significant siderophore activities comparable to that of bacillibactin (4), compounds 13 and 14 exhibit strong cytotoxic activity. At the same time, the strain classification status was confirmed by genomic analyses, and the complete genome sequence of Bacillus siamensis was presented firstly. This study provides a foundation for understanding the mechanisms driving SCSIO 05746's multiple bioactivities and demonstrates a successful way of discovering bioactive metabolites using a combination of genome mining and metabolic profiling methods.


Assuntos
Bacillus/química , Produtos Biológicos/análise , Genoma Bacteriano , Genômica , Redes e Vias Metabólicas/genética , Metabolômica , Bacillus/genética , Mineração de Dados
10.
Int J Mol Sci ; 20(7)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974785

RESUMO

Two Bacillus atrophaeus strains, the first being a highly stress-resistant ATCC 9372 strain and the Ua strain identified from a chromium mine by our lab, differ in their abilities to tolerate and remove Uranium (VI) from contaminated water. An increase in U(VI) concentration in growth media led to a decrease in the tolerance and bio-remedial capacity of both strains. However, under high concentrations of U(VI) in the growth media, the ATCC 9372 strain demonstrated a higher tolerance and a higher removal capacity than the Ua strain. Two approaches, transcriptome sequencing and transgenic technology, were used to elucidate the relationship between particular genes within these two strains and their U(VI) removal capacity. Sequencing confirmed the expression of two genes unique to the Ua strain, previously designated ytiB and ythA. They encode putative proteins that show the highest levels of identity to carbonic anhydrase and cytochrome bd terminal oxidase I, respectively. Using the pBE-S DNA vector, ytiB and ythA were transformed into the ATCC 9372 strain of Bacillus atrophaeus. Under a U(VI) concentration of 120 mg/L, the removal rates of the transgenic ATCC 9372-ytiB and ATCC 9372-ythA strains decreased by 7.55% and 7.43%, respectively, compared to the removal rate of the control strain transformed with empty plasmid. The results suggest that both ythA and ytiB genes have a negative influence on the uranium removing capacity of Bacillus atrophaeus. This finding will help to elucidate the molecular mechanisms of uranium removal by bacteria.


Assuntos
Bacillus , Proteínas de Bactérias , Cromo/metabolismo , Microbiologia do Solo , Urânio/metabolismo , Bacillus/genética , Bacillus/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
11.
BMC Genomics ; 20(1): 283, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975079

RESUMO

BACKGROUND: Members of the genus Bacillus are important plant growth-promoting rhizobacteria that serve as biocontrol agents. Bacillus paralicheniformis MDJK30 is a PGPR isolated from the peony rhizosphere and can suppress plant-pathogenic bacteria and fungi. To further uncover the genetic mechanism of the plant growth-promoting traits of MDJK30 and its closely related strains, we used comparative genomics to provide insights into the genetic diversity and evolutionary relationship between B. paralicheniformis and B. licheniformis. RESULTS: A comparative genomics analysis based on B. paralicheniformis MDJK30 and 55 other previously reported Bacillus strains was performed. The evolutionary position of MDJK30 and the evolutionary relationship between B. paralicheniformis and B. licheniformis were evaluated by studying the phylogeny of the core genomes, a population structure analysis and ANI results. Comparative genomic analysis revealed various features of B. paralicheniformis that contribute to its commensal lifestyle in the rhizosphere, including an opening pan genome, a diversity of transport and the metabolism of the carbohydrates and amino acids. There are notable differences in the numbers and locations of the insertion sequences, prophages, genomic islands and secondary metabolic synthase operons between B. paralicheniformis and B. licheniformis. In particular, we found most gene clusters of Fengycin, Bacitracin and Lantipeptide were only present in B. paralicheniformis and were obtained by horizontal gene transfer (HGT), and these clusters may be used as genetic markers for distinguishing B. paralicheniformis and B. licheniformis. CONCLUSIONS: This study reveals that MDJK30 and the other strains of lineage paralicheniformis present plant growth-promoting traits at the genetic level and can be developed and commercially formulated in agriculture as PGPR. Core genome phylogenies and population structure analysis has proven to be a powerful tool for differentiating B. paralicheniformis and B. licheniformis. Comparative genomic analyses illustrate the genetic differences between the paralicheniformis-licheniformis group with respect to rhizosphere adaptation.


Assuntos
Bacillus/genética , Evolução Molecular , Genômica , Adaptação Fisiológica/genética , Bacillus/metabolismo , Bacillus/fisiologia , Família Multigênica/genética , Filogenia
12.
Appl Microbiol Biotechnol ; 103(11): 4467-4481, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30989253

RESUMO

Locillomycins are cyclic lipononapeptides assembled by a nonlinear hexamodular NRPS and have strong antibacterial activity. In this study, we genetically engineered Bacillus velezensis FZB42 as a surrogate host for the heterologous expression of the loc gene cluster for locillomycins. The fosmid N13 containing whole loc gene cluster was screened from the B. velezensis 916 genomic library. Subsequently, a spectinomycin resistance cassette, and the cassette fused with an IPTG inducible promoter Pspac, was introduced in the fosmid N13 using λ Red recombination system, respectively. The resulting fosmids, designated N13+Spec and N13+PSSpec, were used for the transformation of B. velezensis FZB42 to obtain derivative strains FZBNPLOC and FZBPSLOC. RT-PCR and qRT-PCR results revealed the efficient heterologous expression of the loc gene cluster in both derivative strains. Particularly, there was positive correlation between the derivative FZBPSLOC strain and the enhanced production of locillomycins upon addition of the inducer IPTG with the highest production of locillomycins at 15-fold more than that of B. velezensis 916. This overproduction of locillomycins was also related to the enhancement of antibacterial activity against methicillin-resistant Staphylococcus aureus, and exhibited moderate changes in its hemolytic activity. Together our findings demonstrate that the nonlinear hexamodular NRPS, encoded by the loc gene cluster from B. velezensis 916, is sufficient for the biosynthesis of cyclic lipononapeptide locillomycins in the surrogate host B. velezensis FZB42. Moreover, the FZBPSLOC strain will also be useful for further development of novel locillomycins derivatives with improved antibacterial activity.


Assuntos
Antibacterianos/biossíntese , Bacillus/metabolismo , Proteínas de Bactérias/biossíntese , Vias Biossintéticas/genética , Lipopeptídeos/biossíntese , Engenharia Metabólica/métodos , Peptídeos Cíclicos/biossíntese , Proteínas Recombinantes/biossíntese , Bacillus/genética , Proteínas de Bactérias/genética , Expressão Gênica , Lipopeptídeos/genética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Família Multigênica , Peptídeos Cíclicos/genética , Proteínas Recombinantes/genética
13.
J Microbiol Biotechnol ; 29(5): 794-808, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31030454

RESUMO

Bacillus velezensis strain WRN014 was isolated from banana fields in Hainan, China. Bacillus velezensis is an important member of the plant growth-promoting rhizobacteria (PGPR) which can enhance plant growth and control soil-borne disease. The complete genome of Bacillus velezensis WRN014 was sequenced by combining Illumina Hiseq 2500 system and Pacific Biosciences SMRT high-throughput sequencing technologies. Then, the genome of Bacillus velezensis WRN014, together with 45 other completed genome sequences of the Bacillus velezensis strains, were comparatively studied. The genome of Bacillus velezensis WRN014 was 4,063,541bp in length and contained 4,062 coding sequences, 9 genomic islands and 13 gene clusters. The results of comparative genomic analysis provide evidence that (i) The 46 Bacillus velezensis strains formed 2 obviously closely related clades in phylogenetic trees. (ii) The pangenome in this study is open and is increasing with the addition of new sequenced genomes. (iii) Analysis of single nucleotide polymorphisms (SNPs) revealed local diversification of the 46 Bacillus velezensis genomes. Surprisingly, SNPs were not evenly distributed throughout the whole genome. (iv) Analysis of gene clusters revealed that rich gene clusters spread over Bacillus velezensis strains and some gene clusters are conserved in different strains. This study reveals that the strain WRN014 and other Bacillus velezensis strains have potential to be used as PGPR and biopesticide.


Assuntos
Bacillus/genética , Genes Bacterianos/genética , Sequenciamento Completo do Genoma/métodos , Bacillus/classificação , Bacillus/isolamento & purificação , Sequência de Bases , China , Mapeamento Cromossômico , DNA Bacteriano/análise , DNA Bacteriano/genética , Variação Genética , Genoma Bacteriano , Família Multigênica , Musa/microbiologia , Mutação , Filogenia , Desenvolvimento Vegetal , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Metabolismo Secundário/genética , Análise de Sequência de DNA
14.
Bioengineered ; 10(1): 13-22, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30836830

RESUMO

The deep-sea bacterium strain FA13 was isolated from the sediment of the South Atlantic Ocean and identified as Bacillus circulans based on 16S ribosomal DNA sequence. Through liquid fermentation with five media, the cell-free supernatant fermented with ISP2 showed the highest inhibition activities against mycelial growth of Aspergillus parasiticus mutant strain NFRI-95 and accumulation of norsolorinic acid, a precursor for aflatoxin production. Based on ISP2, uniform design was used to optimize medium formula and fermentation conditions. After optimization, the inhibition efficacy of the 20-time diluted supernatant against A. parasiticus NFRI-95 mycelial growth and aflatoxin production was increased from 0-23.1% to 100%. Moreover, compared to the original protocol, medium cost and fermentation temperature were significantly reduced, and dependence on seawater was completely relieved, thus preventing the fermentor from corrosion. This is the first report of a deep-sea microorganism which can inhibit A. parasiticus NFRI-95 mycelial growth and aflatoxin production.


Assuntos
Aflatoxinas/antagonistas & inibidores , Antraquinonas/antagonistas & inibidores , Antitoxinas/isolamento & purificação , Aspergillus/efeitos dos fármacos , Bacillus/metabolismo , Micélio/efeitos dos fármacos , Aflatoxinas/biossíntese , Antraquinonas/metabolismo , Antitoxinas/farmacologia , Organismos Aquáticos , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Aspergillus/patogenicidade , Oceano Atlântico , Bacillus/classificação , Bacillus/genética , Bacillus/isolamento & purificação , Reatores Biológicos , Meios de Cultura/química , Análise Fatorial , Fermentação , Sedimentos Geológicos/microbiologia , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Micélio/patogenicidade , Filogenia , RNA Ribossômico 16S/genética , Temperatura Ambiente
15.
Int J Biol Macromol ; 131: 752-759, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30904535

RESUMO

A novel beta-1,4-glucanase was purified and characterized from symbiotic Bacillus sp. CF96 of termite. The SDS-PAGE and zymogram analyses revealed a molecular mass of 35.6 kDa. Optimal activity was at 50 °C and pH 5.5, while the enzyme was active over a wide range of temperature 20-80 °C and pH 4-10 and interestingly more than 60% of the maximum activity remained up to pH 9. The enzyme activity increased in the presence of hexane, chloroform and methanol (20% v/v). while, the enzyme activity was inhibited by metal ions such as Mn2+, Hg2+, Cu2+, Zn2+, Mg2+, Fe2+. The isolated enzyme was able to degrade carboxymethyl cellulose (CMC), avicel and cellulose. Cellobiose was the hydrolytic product of enzymatic reaction based on thin layer chromatography (TLC) analysis. Regarding beta-1,4 endo/exoglucanase activity and high temperature, pH and solvent stability, the enzyme has potential for various industrial applications especially in designing pesticide for termite.


Assuntos
Bacillus/enzimologia , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Isópteros/microbiologia , Animais , Bacillus/classificação , Bacillus/genética , Bacillus/isolamento & purificação , Fenômenos Químicos , Cromatografia em Camada Delgada , Ativação Enzimática , Estabilidade Enzimática , Glicosídeo Hidrolases/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Solventes , Especificidade por Substrato , Simbiose , Temperatura Ambiente
16.
Appl Microbiol Biotechnol ; 103(9): 3669-3682, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30911788

RESUMO

Some members of the Bacillus velezensis (Bv) group (e.g., Bv FZB42T and AS3.43) were previously assigned grouping with B. subtilis and B. amyloliquefaciens, based on the fact that they shared a 99% DNA-DNA percentage phylogenetic similarity. However, hinging on current assessments of the pan-genomic reassignments, the differing phylogenomic characteristics of Bv from B. subtilis and B. amyloliquefaciens are now better understood. Within this re-grouping/reassignment, the various strains within the Bv share a close phylogenomic resemblance, and a number of these strains have received a lot of attention in recent years, due to their genomic robustness, and the growing evidence for their possible utilization in the agricultural industry for managing plant diseases. Only a few applications for their use medicinally/pharmaceutically, environmentally, and in the food industry have been reported, and this may be due to the fact that the majority of those strains investigated are those typically occurring in soil. Although the intracellular unique biomolecules of Bv strains have been revealed via in silico genome modeling and investigated using transcriptomics and proteomics, a further inquisition into the Bv metabolome using newer technologies such as metabolomics could elucidate additional applications of this economically relevant Bacillus species, beyond that of primarily the agricultural sector.


Assuntos
Bacillus/classificação , Bacillus/metabolismo , Filogenia , Bacillus/genética , Bacillus/isolamento & purificação , Microbiologia de Alimentos , Genoma Bacteriano , Genômica , Microbiologia Industrial , Metaboloma
17.
Molecules ; 24(6)2019 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-30884857

RESUMO

Bacillus velezensis is an aerobic, gram-positive, endospore-forming bacterium that promotes plant growth. Numerous strains of this species have been reported to suppress the growth of microbial pathogens, including bacteria, fungi, and nematodes. Based on recent phylogenetic analysis, several Bacillus species have been reclassified as B. velezensis. However, this information has yet to be integrated into a well-organized resource. Genomic analysis has revealed that B. velezensis possesses strain-specific clusters of genes related to the biosynthesis of secondary metabolites, which play significant roles in both pathogen suppression and plant growth promotion. More specifically, B. velezensis exhibits a high genetic capacity for synthesizing cyclic lipopeptides (i.e., surfactin, bacillomycin-D, fengycin, and bacillibactin) and polyketides (i.e., macrolactin, bacillaene, and difficidin). Secondary metabolites produced by B. velezensis can also trigger induced systemic resistance in plants, a process by which plants defend themselves against recurrent attacks by virulent microorganisms. This is the first study to integrate previously published information about the Bacillus species, newly reclassified as B. velezensis, and their beneficial metabolites (i.e., siderophore, bacteriocins, and volatile organic compounds).


Assuntos
Bacillus/metabolismo , Genoma Bacteriano/genética , Lipopeptídeos/biossíntese , Desenvolvimento Vegetal/genética , Bacillus/genética , Agentes de Controle Biológico/química , Lipopeptídeos/química , Oligopeptídeos/biossíntese , Oligopeptídeos/química , Peptídeos/química , Peptídeos/metabolismo , Filogenia , Plantas/microbiologia
18.
Int J Biol Macromol ; 131: 445-452, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30876900

RESUMO

Bacterium Bacillus sp. SS105, isolated from Free Air CO2 Enriched (FACE) soil was previously screened for carbonic anhydrase activity and CO2 sequestration. In this study, strain was selected to amplify carbonic anhydrase encoding genes. The CA genes from Bacillus sp. SS105 were found to be homologous with beta­carbonic anhydrase (ß-CA) and gamma­carbonic anhydrase (γ-CA). Both types of CA genes was cloned in pET30b (+) and expressed in E coliBL21 (DE3) with His-tag at the N-terminus. The recombinant proteins were purified by Ni-NTA affinity chromatography. The molecular size of ß-CA and γ-CA were approximately 27 kDa and 25 kDa respectively. The optimum pH and temperature were found to be 8.0 and 37 °C respectively. The Zn+ was enhancing the CAs enzyme activity. Anions and modulators showed inhibitory effect on CAs at specific concentration. Functional domain analysis of both CA proteins showed conserved region of respective proteins. Recombinant enzymes were used for bio-mineralization based conversion of atmospheric CO2 into valuable calcite. Calcite formation was evaluated with or without use of enzymes and confirmed by SEM and XRD analysis. SEM result confirmed the conversion of flower-shaped unstable form of vaterite to hexagonal cubic stable form of calcite in presence of enzymes.


Assuntos
Bacillus/genética , Biomimética , Dióxido de Carbono/química , Anidrases Carbônicas/química , Anidrases Carbônicas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Bacillus/classificação , Bacillus/enzimologia , Biomimética/métodos , Anidrases Carbônicas/isolamento & purificação , Cromatografia de Afinidade , Clonagem Molecular , Ativação Enzimática , Estabilidade Enzimática , Expressão Gênica , Concentração de Íons de Hidrogênio , Cinética , Filogenia , Proteínas Recombinantes/isolamento & purificação , Análise Espectral , Temperatura Ambiente
19.
Food Microbiol ; 81: 32-39, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30910086

RESUMO

Members of the Bacillus cereus sensu lato (B. cereus group) are spore-forming organisms commonly associated with spoilage of milk and dairy products. Previous studies have shown, by using 16S marker gene sequencing, that the genus Bacillus is part of the core microbiota of raw bovine milk and that some members of this genus are able to grow during sub-optimal storage (8 °C) of pasteurized consumption milk. Here, the composition of this genus in pasteurized consumption milk samples, collected from two dairies, over a one-year period and stored at 4 or 8 °C up to the end of shelf life is uncovered. Our results show that the B. cereus group is the dominant Bacillus group in stored consumption milk. By applying a new marker gene sequencing approach, several dominating phylogenetic clusters were identified within the B. cereus group populations from the milk samples. There was a higher phylogenetic diversity among bacteria from milk stored at 8 °C compared to milk stored at 4 °C. Sampling period and the dairy the samples were collected from, also significantly influenced the diversity, which shows that the B. cereus group population in consumption milk is heterogeneous and subjected to temporal and spatial changes. The new approach applied in this study will facilitate the identification of isolates within the B. cereus group, of which some are potential spoilage bacteria and pathogenic contaminants of milk and dairy products.


Assuntos
Bacillus cereus/classificação , Bacillus cereus/genética , Microbiologia de Alimentos , Leite/microbiologia , Animais , Bacillus/classificação , Bacillus/genética , Sequência de Bases , Biodiversidade , Bovinos , DNA Bacteriano/isolamento & purificação , Contaminação de Alimentos/análise , Armazenamento de Alimentos , Biblioteca Gênica , Genes Bacterianos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Microbiota , Filogenia , RNA Ribossômico 16S/genética , Esporos Bacterianos , Temperatura Ambiente
20.
Int J Food Microbiol ; 297: 41-50, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-30878841

RESUMO

Butyrate and its derivates pertain to the key aroma contributors of strong-flavour baijiu, a kind of Chinese liquors, that is produced from grains by solid-state multispecies anaerobic fermentation in a mud cellar. Microbes inhabiting in the fermentation pit mud largely determines baijiu's flavour and quality. In order to shed light on the microbial functional groups driving butyrate production in pit mud, clone library analysis was firstly performed and the results demonstrated that Clostridia (relative abundance: 50%) and Bacilli (37%) were major groups possessing butyrate kinase (buk) pathway and Clostridia (98%) dominated butyryl-CoA:acetate CoA-transferase (but) pathway. According to Clostridial specific-16S rRNA gene sequencing analysis, we found the resilience character of Clostridial community in pit mud. Amongst Clostridial groups, 32.0% of the sequences were grouped into Clostridiales incertae sedis, followed by Heliobacteriaceae (18.3%) and Clostridiaceae 1 (8.4%). Moreover, Hydrogenispora, Sedimentibacter and Clostridium were the top three abundant genera. Relative abundance of Hydrogenispora was higher in the late days of fermentation, while Sedimentibacter exhibited higher proportion in the early days. Different from the previous studies using universal bacterial primer sets, Hydrogenispora was first reported as one dominant genus in pit mud. As for the reported potential butyrate producer Clostridium, nineteen species were obtained and ten of them were first isolated from the pit mud. Amongst them, buk was identified in eleven species by PCR analysis, while but was identified in the other seven, indicating the species-specific butyrate synthesis pathways of Clostridium. This study provides a perspective on targeting and isolating specific functional microbes in baijiu microbiota with the gene sequence-based medium prediction method.


Assuntos
Bebidas Alcoólicas , Clostridium/enzimologia , Clostridium/genética , Fermentação , Microbiologia do Solo , Bebidas Alcoólicas/microbiologia , Bacillus/enzimologia , Bacillus/genética , Butiratos/metabolismo , Microbiota/genética , RNA Ribossômico 16S/genética
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