Transcriptomic and Ectoine Analysis of Halotolerant Nocardiopsis gilva YIM 90087T Under Salt Stress

Abstract

The genus <i>Nocardiopsis</i> is an unique actinobacterial group that widely distributed in hypersaline environments. In this study, we investigated the growth conditions, transcriptome analysis, production and accumulation of ectoine by <i>Nocardiopsis gilva</i> YIM 90087^T under salt stress. The colony color of <i>N. gilva</i> YIM 90087^T changed from yellow to white under salt stress conditions. Accumulation of ectoine and hydroxyectoine in cells was an efficient way to regulate osmotic pressure. The ectoine synthesis was studied by transferring the related genes (<i>ectA, ectB</i>, and <i>ectC</i>) to <i>Escherichia coli</i>. Transcriptomic analysis showed that the pathways of ABC transporters (ko02010) and glycine, serine, and threonine metabolism (ko00260) played a vital role under salt stress environment. The <i>ectABC</i> from <i>N. gilva</i> YIM 90087^T was activated under the salt stress. Addition of exogenous ectoine and hydroxyectoine were helpful to protect <i>N. gilva</i> YIM 90087^T from salt stress.