Microbial population index and community structure in saline-alkaline soil using gene targeted metagenomics.
Population indices of bacteria and archaea were investigated from saline-alkaline soil and a possible microbe-environment pattern was established using gene targeted metagenomics. Clone libraries were constructed using 16S rRNA and functional gene(s) involved in carbon fixation (cbbL), nitrogen fixation (nifH), ammonia oxidation (amoA) and sulfur metabolism (apsA). Molecular phylogeny revealed the dominance of Actinobacteria, Firmicutes and Proteobacteria along with archaeal members of Halobacteraceae. The library consisted of novel bacterial (20%) and archaeal (38%) genera showing ≤95% similarity to previously retrieved sequences. Phylogenetic analysis indicated ability of inhabitant to survive in stress condition. The 16S rRNA gene libraries contained novel gene sequences and were distantly homologous with cultured bacteria. Functional gene libraries were found unique and most of the clones were distantly related to Proteobacteria, while clones of nifH gene library also showed homology with Cyanobacteria and Firmicutes. Quantitative real-time PCR exhibited that bacterial abundance was two orders of magnitude higher than archaeal. The gene(s) quantification indicated the size of the functional guilds harboring relevant key genes. The study provides insights on microbial ecology and different metabolic interactions occurring in saline-alkaline soil, possessing phylogenetically diverse groups of bacteria and archaea, which may be explored further for gene cataloging and metabolic profiling.
Discipline of Marine Biotechnology and Ecology, CSIR-Central Salt and Marine Chemicals Research Institute (CSMCRI), G. B. Marg, Bhavnagar 364002, Gujarat, India.
Jitendra
J
Keshri
Avinash
A
Mishra
Bhavanath
B
Jha
D001105:Archaea / Q000145:classification* / Q000235:genetics; D019843:Archaeal Proteins / Q000235:genetics; D001419:Bacteria / Q000145:classification* / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D058448:Biota; D016000:Cluster Analysis; D019641:DNA, Archaeal / Q000737:chemistry / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D020459:Genes, rRNA; D006863:Hydrogen-Ion Concentration; D056186:Metagenomics; D008969:Molecular Sequence Data; D010802:Phylogeny; D019642:RNA, Archaeal / Q000235:genetics; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D054712:Salinity; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology
D019843:Archaeal Proteins; D001426:Bacterial Proteins; D019641:DNA, Archaeal; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D019642:RNA, Archaeal; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D012987:Soil