The Rhizobacterium Bacillus amyloliquefaciens subsp. plantarum NAU-B3 Contains a Large Inversion within the Central Portion of the Genome

Wu H, Qiao J, Blom J, et al. The Rhizobacterium Bacillus amyloliquefaciens subsp. plantarum NAU-B3 Contains a Large Inversion within the Central Portion of the Genome. Genome announcements. 2013;1(6):e00941-13.The genome of rhizobacterium Bacillus amyloliquefaciens subsp. plantarum strain NAU-B3 is 4,196,170 bp in size and harbors 4,001 genes. Nine giant gene clusters are dedicated to the nonribosomal synthesis of antimicrobial lipopeptides and polyketides. Remarkably, NAU_B3 contains a large inversion within the central portion of the genome

Two-Component Response Regulator DegU Controls the Expression of Bacilysin in Plant-Growth-Promoting Bacterium Bacillus amyloliquefaciens FZB42

The plant-growth-promoting-rhizobacteria Bacillus amyloliquefaciens FZB42 possess an enormous potential to synthesize a wide range of antimicrobial, antiviral and nematocidal compounds. One of them, the dipeptide antibiotic bacilysin, is synthesized by FZB42 during exponential growth. Here, we have demonstrated that bacilysin is positively regulated by the two-component response regulator DegU at the transcriptional level. In addition, ScoC (Hpr), a transition state regulator, negatively controlled expression of the bacA gene, which is the first gene within the bacilysin operon. Both DegU and ScoC were bound directly at the bacA promoter region. Furthermore, a monocistronic gene located in close vicinity of the bac operon and essential for bacilysin production, ywfH, was also regulated by DegU. Transcription of the bac operon and of the ywfH gene in B. amyloliquefaciens FZB42 was positively controlled by the DegU global regulator protein. The role of interactions within a ternary complex formed by the antagonistically acting regulators DegU and ScoC as well as the bacA promoter sequence remains to be elucidated.Peer Reviewe

Genome sequence data of Bacillus velezensis BP1.2A and BT2.4

Here, we report the complete genome sequence data of the biocontrol strains Bacillus velezensis BP1.2A and BT2.4 isolated from Vietnamese crop plants. The size of the genomes is 3,916,868 bp (BP1.2A), and 3,922,686 bp (BT2.4), respectively. The BioProjects have been deposited at NCBI GenBank. The GenBank accession numbers for the B. velezensis strains are PRJNA634914 (BP1.2A) and PRJNA634832 (BT2.4) for the BioProjects, CP085504 (BP1.2A) and CP085505 (BT2.4) for the chromosomes, GCA_013284785.2 (BP2.1A), and GCA_013284785.2 (BT2.4) for GenBank assembly accessions, and SAMN15012571 (BP1.2A) and SAMN15009897 (BT2.4) for the BioSamples. Both genomes were closely related to FZB42, the model strain for plant growth promoting bacilli.Peer Reviewe

Investigation of the potential of Brevibacillus spp. for the biosynthesis of nonribosomally produced bioactive compounds by combination of genome mining with MALDI-TOF mass spectrometry

The biosynthetic potential of 11 Brevibacillus spp. strains was investigated by combination of genome mining with mass spectrometric analysis using MALDI-TOF mass spectrometry. These endophytic, plant associated Brevibacillus strains were isolated from crop plants, such as coffee and black pepper, in Vietnam. Draft genomes of these strains were available. They were classified (a) by comparison with type strains and a collection of genome-sequenced Brevibacillus spp. deposited in the NCBI data base as well as (b) by construction of a phylogenetic tree from the core sequences of publicly available genomes of Brevibacillus strains. They were identified as Brevibacillus brevis (1 strain); parabrevis (2 strains); porteri (3 strains); and 5 novel Brevibacillus genomospecies. Our work was specifically focused on the detection and characterization of nonribosomal peptides produced by these strains. Structural characterization of these compounds was performed by LIFT-MALDI-TOF/TOF mass spectrometric sequence analysis. The highlights of our work were the demonstration of the tyrocidines, a well-known family of cyclodecapeptides of great structural variability, as the main products of all investigated strains and the identification of a novel class of pentapeptides produced by B. brevis; B. schisleri; and B. porteri which we designate as brevipentins. Our biosynthetic studies demonstrate that knowledge of their biosynthetic capacity can efficiently assist classification of Brevibacillus species.Peer Reviewe

Whole genome sequence comparisons in taxonomoy

This chapter is devoted to application of whole genome sequence comparisons in taxonomy. Driven by the rapid progress in sequencing technologies, “low budget” bacterial genomes become increasingly available in a nearly unlimited number. During finalizing this chapter, completed genomes representing 1,604 bacterial and 85 archaeal species were present in the public data bank (http://www.ncbi.nlm.nih.gov/sutils/genom_table.cgi) reflecting the enormous progress made within sequencing microbial genomes in the last years. With the advent of next generation sequencing, whole genome sequence comparisons will be more and more important for taxonomy, especially valuable in elucidating relationship of groups of closely related bacterial strains which might form a single taxon, a subspecies or just an ecovar within a given species. The aim of this chapter is to hand out a tool set for applying genomics to the interested taxonomist. Using these tools might prove as being useful especially in refining groups of closely related strains, which are not resolved by their 16S rRNA sequence. Here, we will exemplify this approach by selecting a specific group of plant – associated Bacillus amyloliquefaciens strains with plant growth promoting properties. In recent years, those strains were increasingly applied as biological substitutes of agrochemicals, mainly used as biofertilizer and for biocontrol of phytopathogenic microorganisms, and nematodes (Chen et al., 2007).http://www.sciencedirect.com/science/bookseries/05809517hb2016Biochemistr

Two plant-associated Bacillus velezensis strains selected after genome analysis, metabolite profiling, and with proved biocontrol potential, were enhancing harvest yield of coffee and black pepper in large field trials

Elimination of chemically synthesized pesticides, such as fungicides and nematicides, in agricultural products is a key to successful practice of the Vietnamese agriculture. We describe here the route for developing successful biostimulants based on members of the Bacillus subtilis species complex. A number of endospore-forming Gram-positive bacterial strains with antagonistic action against plant pathogens were isolated from Vietnamese crop plants. Based on their draft genome sequence, thirty of them were assigned to the Bacillus subtilis species complex. Most of them were assigned to the species Bacillus velezensis. Whole genome sequencing of strains BT2.4 and BP1.2A corroborated their close relatedness to B. velezensis FZB42, the model strain for Gram-positive plant growth-promoting bacteria. Genome mining revealed that at least 15 natural product biosynthesis gene clusters (BGCs) are well conserved in all B. velezensis strains. In total, 36 different BGCs were identified in the genomes of the strains representing B. velezensis, B. subtilis, Bacillus tequilensis, and Bacillus. altitudinis. In vitro and in vivo assays demonstrated the potential of the B. velezensis strains to enhance plant growth and to suppress phytopathogenic fungi and nematodes. Due to their promising potential to stimulate plant growth and to support plant health, the B. velezensis strains TL7 and S1 were selected as starting material for the development of novel biostimulants, and biocontrol agents efficient in protecting the important Vietnamese crop plants black pepper and coffee against phytopathogens. The results of the large-scale field trials performed in the Central Highlands in Vietnam corroborated that TL7 and S1 are efficient in stimulating plant growth and protecting plant health in large-scale applications. It was shown that treatment with both bioformulations resulted in prevention of the pathogenic pressure exerted by nematodes, fungi, and oomycetes, and increased harvest yield in coffee, and pepper.Peer Reviewe

Complete genome sequence and epigenetic profile of Bacillus velezensis UCMB5140 used for plant and crop protection in comparison with other plant-associated Bacillus strains

The application of biocontrol biopesticides based on plant growth–promoting rhizobacteria (PGPR), particularly members of the genus Bacillus, is considered a promising perspective to make agricultural practices sustainable and ecologically safe. Recent advances in genome sequencing by third-generation sequencing technologies, e.g., Pacific Biosciences’ Single Molecule Real-Time (PacBio SMRT) platform, have allowed researchers to gain deeper insights into the molecular and genetic mechanisms of PGPR activities, and to compare whole genome sequences and global patterns of epigenetic modifications. In the current work, this approach was used to sequence and compare four Bacillus strains that exhibited various PGPR activities including the strain UCMB5140, which is used in the commercial biopesticide Phytosubtil. Whole genome comparison and phylogenomic inference assigned the strain UCMB5140 to the species Bacillus velezensis. Strong biocontrol activities of this strain were confirmed in several bioassays. Several factors that affect the evolution of active PGPR B. velezensis strains were identified: (1) horizontal acquisition of novel non-ribosomal peptide synthetases (NRPS) and adhesion genes; (2) rearrangements of functional modules of NRPS genes leading to strain specific combinations of their encoded products; (3) gain and loss of methyltransferases that can cause global alterations in DNA methylation patterns, which eventually may affect gene expression and regulate transcription. Notably, we identified a horizontally transferred NRPS operon encoding an uncharacterized polypeptide antibiotic in B. velezensis UCMB5140. Other horizontally acquired genes comprised a possible adhesin and a methyltransferase, which may explain the strain-specific methylation pattern of the chromosomal DNA of UCMB5140.The South African National Research Foundation (NRF), the joint NRF/COSTECH (Tanzanian Commission for Science and Technology), joint TIA (Technology Innovation Agency of South Africa)/COSTECHPhD and MSc student fellowship grants from Southern African Biochemistry and Informatics for Natural Products (SABINA, http://www.sabina-africa.org/) and Agroscope through its research program Microbial Biodiversity.http://link.springer.com/journal/2532021-07-10hj2020BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog