Ahmed Vasim, Verma Manoj K, Gupta Shashank, Mandhan Vibha, Chauhan Nar S
Department of Biochemistry, Maharshi Dayanand University, Rohtak, India.
Front Microbiol. 2018 Feb 8;9:159. doi: 10.3389/fmicb.2018.00159. eCollection 2018.
Osmotolerance is one of the critical factors for successful survival and colonization of microbes in saline environments. Nonetheless, information about these osmotolerance mechanisms is still inadequate. Exploration of the saline soil microbiome for its community structure and novel genetic elements is likely to provide information on the mechanisms involved in osmoadaptation. The present study explores the saline soil microbiome for its native structure and novel genetic elements involved in osmoadaptation. 16S rRNA gene sequence analysis has indicated the dominance of halophilic/halotolerant phylotypes affiliated to , and . A functional metagenomics approach led to the identification of osmotolerant clones SSR1, SSR4, SSR6, SSR2 harboring , and genes. Furthermore, transposon mutagenesis, genetic, physiological and functional studies in close association has confirmed the role of these genes in osmotolerance. Enhancement in host osmotolerance possibly though the cytosolic accumulation of amino acids, reducing equivalents and osmolytes involving , and . Decoding of the genetic elements prevalent within these microbes can be exploited either as such for ameliorating soils or their genetically modified forms can assist crops to resist and survive in saline environment.
渗透压耐受性是微生物在盐环境中成功生存和定殖的关键因素之一。尽管如此，关于这些渗透压耐受机制的信息仍然不足。探索盐渍土壤微生物群落的结构和新的遗传元件可能会提供有关渗透适应机制的信息。本研究探索了盐渍土壤微生物群落的天然结构以及参与渗透适应的新遗传元件。16S rRNA基因序列分析表明，属于[具体分类]的嗜盐/耐盐系统型占主导地位。功能宏基因组学方法导致鉴定出携带[具体基因]的耐渗透压克隆SSR1、SSR4、SSR6、SSR2。此外，转座子诱变、遗传学、生理学和功能研究紧密结合，证实了这些基因在渗透压耐受性中的作用。通过氨基酸的胞质积累、还原当量和渗透溶质（包括[具体物质]）可能增强宿主的渗透压耐受性。解码这些微生物中普遍存在的遗传元件，既可以直接用于改良土壤，也可以将其转基因形式用于帮助作物在盐环境中抵抗和生存。
