title: Application of targeted metagenomics to explore abundance and diversity of CO₂-fixing bacterial community using cbbL gene from the rhizosphere of Arachis hypogaea.
abstract: Sequestration of CO(2) by autotrophic bacteria is a key process of biogeochemical carbon cycling in soil ecosystem. Rhizosphere is a rich niche of microbial activity and diversity, influenced by change in atmospheric CO(2). Structural changes in rhizosphere composition influence microbial communities and the nutrient cycling. In the present study, the bacterial diversity and population dynamics were established using cbbL and 16S rRNA gene targeted metagenomics approach from the rhizosphere of Arachis hypogaea. A total of 108 cbbL clones were obtained from the rhizospheric soil which revealed predominance of cbbL sequences affiliated to Rhizobium leguminosarum, Bradyrhizobium sp., Sinorhizobium meliloti, Ochrobactrum anthropi and a variety of uncultured cbbL harboring bacteria. The 16S rRNA gene clone library exhibited the dominance of Firmicutes (34.4%), Proteobacteria (18.3%), Actinobacteria (17.2%) and Bacteroidetes (16.1%). About 43% nucleotide sequences of 16S rRNA gene clone library were novel genera which showed <95% homology with published sequences. Gene copy number of cbbL and 16S rRNA genes, determined by quantitative real-time PCR (qRT PCR), was 9.38 ± 0.75 × 10(7) and 5.43 ± 0.79 × 10(8) (per g dry soil), respectively. The results exhibited bacterial community structure with high bacterial diversity and abundance of CO(2)-fixing bacteria, which can be explored further for their role in carbon cycling, sustainable agriculture and environment management.
authors: Discipline of Marine Biotechnology and Ecology, CSIR - Central Salt and Marine Chemicals Research Institute, G B Marg, Bhavnagar- 364002, Gujarat, India.
authors: Basit
authors: B
authors: Yousuf
authors: Jitendra
authors: J
authors: Keshri
authors: Avinash
authors: A
authors: Mishra
authors: Bhavanath
authors: B
authors: Jha
mesh_terms: D010367:Arachis / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology*; D001483:Base Sequence; D057486:Carbon Cycle / Q000235:genetics; D002245:Carbon Dioxide / Q000378:metabolism; D003001:Cloning, Molecular; D018628:Gene Dosage; D015723:Gene Library; D005798:Genes, Bacterial; D056186:Metagenomics; D008969:Molecular Sequence Data; D010802:Phylogeny; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D058441:Rhizosphere
chemical_list: D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D002245:Carbon Dioxide