Zymomonas mobilis subsp. mobilis low pH mutants RNA-Seq. Zymomonas mobilis subsp. mobilis

In this study, adaptive laboratory evolution (ALE) strategy was applied to adapt Z. mobilis under acidic pH condition. Two mutant strains named 3.6M and 3.5M with enhanced acidic-pH tolerance were selected and confirmed. Mutant strains 3.6M and 3.5M exhibited 50~130% enhancement on growth rate, 4~9 h reduction on fermentation time, and 20~63% improvement on ethanol productivity than wild-type ZM4 at pH 3.8. Next-generation sequencing (NGS)-based whole-genome resequencing (WGR) and RNA-Seq technologies were applied to unravel the acidic pH tolerance mechanism of mutant strains.