Draft Genome Sequence of Biological N2-Fixing Bacterium Rhizobium tropici A12, Isolated from Root Nodule of Tropical Soybean (Glycine max), TGx-1148 Variety.
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ABSTRACT:
SUBMITTER: Khayi S
PROVIDER: S-EPMC7225531 | biostudies-literature | 2020 May
REPOSITORIES: biostudies-literature
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Draft Genome Sequence of Biological N<sub>2</sub>-Fixing Bacterium Rhizobium tropici A12, Isolated from Root Nodule of Tropical Soybean (Glycine max), TGx-1148 Variety.
Khayi Slimane S Mentag Rachid R Jemo Martin M
Microbiology resource announcements 20200514 20
Here, we present the genome sequence and annotated features of <i>Rhizobium tropici</i> strain A12, which is able to nodulate tropical <i>Glycine max</i> (soybean). The draft genome of the strain consists of 107 contigs totaling 6.5 Mbp in size. The annotation revealed 6,204 protein-coding genes, 52 tRNAs, and 7 rRNAs. ...[more]
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Project description:Rhizobium tropici strain:A12 Genome sequencing and assembly
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Project description:Rhizobium tropici CIAT899 is a nodule-forming α-proteobacterium displaying intrinsic resistance to several abiotic stress conditions such as low soil pH and high temperatures, which are common in tropical environments. It is a good competitor for Phaseolus vulgaris (common bean) nodule occupancy at low pH values, however little is known about the genetic or physiological basis of acid tolerance about gene expression under acidic conditions. To identify genes responding to pH stress we studied the transcriptomes of cells grown under different pH conditions. RNA was extracted from cells grown for several generations in minimal medium at 6.8 or 4.5 (adapted cells). In addition, we acid-shocked cells pre-grown at pH 6.8 for 45 minutes at pH 4.5. Transcriptomes were determined by RNA-Seq. From a total of 6289 protein-coding genes, 383 were found to be differentially expressed under acidic conditions versus control, among which 351 were induced and 32 repressed; only 11 genes were induced upon acid shock. The acid stress response of R. tropici CIAT899 is versatile: we found genes encoding response regulators and membrane transporters, but also enzymes involved in amino acid and carbohydrate metabolism and proton extrusion. Our findings enhance our understanding of the core genes that are important during the acid stress response in R. tropici.
2018-05-17 | GSE108074 | GEO
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Project description:Rhizobium tropici CIAT899 is a nodule-forming ?-proteobacterium displaying intrinsic resistance to several abiotic stress conditions such as low pH and high temperatures, which are common in tropical environments. It is a good competitor for Phaseolus vulgaris (common bean) nodule occupancy at low pH values, however little is known about the genetic and physiological basis of the tolerance to acidic conditions. To identify genes in R. tropici involved in pH stress response we combined two different approaches: (1) A Tn5 mutant library of R. tropici CIAT899 was screened and 26 acid-sensitive mutants were identified. For 17 of these mutants, the transposon insertion sites could be identified. (2) We also studied the transcriptomes of cells grown under different pH conditions using RNA-Seq. RNA was extracted from cells grown for several generations in minimal medium at 6.8 or 4.5 (adapted cells). In addition, we acid-shocked cells pre-grown at pH 6.8 for 45 min at pH 4.5. Of the 6,289 protein-coding genes annotated in the genome of R. tropici CIAT 899, 383 were differentially expressed under acidic conditions (pH 4.5) vs. control condition (pH 6.8). Three hundred and fifty one genes were induced and 32 genes were repressed; only 11 genes were induced upon acid shock. The acid stress response of R. tropici CIAT899 is versatile: we found genes encoding response regulators and membrane transporters, enzymes involved in amino acid and carbohydrate metabolism and proton extrusion, in addition to several hypothetical genes. Our findings enhance our understanding of the core genes that are important during the acid stress response in R. tropici.
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Project description:Forms nitrogen-fixing nodules on the roots of the common bean
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