BackgroundLignocellulose-derived aldehyde inhibitors seriously blocked the biorefinery of biofuels and biochemicals. To date, the economic production of lignocellulose-based products heavily relied on high productivities of fermenting strains. However, it was expensive and time-consuming for the achievable rational modification to strengthen stress tolerance robustness of aldehyde inhibitors. Here, it aimed to improve aldehyde inhibitors tolerance and cellulosic bioethanol fermentability for the chassisZymomonas mobilisZM4 pretreated using energy-efficient and eco-friendly cold plasma.ResultsIt was found that bioethanol fermentability was weaker in CSH (corn stover hydrolysates) than that in synthetic medium forZ. mobilis, and thus was attributed to the inhibition of the lignocellulose-derived aldehyde inhibitors in CSH. Convincingly, it further confirmed that the mixed aldehydes severely decreased bioethanol accumulation through additional aldehydes supplementary assays in synthetic medium. After assayed under different processing time (10–30 s), discharge power (80–160 W), and working pressure (120–180 Pa) using cold atmosphere plasma (CAP), it achieved the increased bioethanol fermentability forZ. mobilisafter pretreated at the optimized parameters (20 s, 140 W and 165 Pa). It showed that cold plasma brought about three mutation sites includingZMO0694(E220V),ZMO0843(L471L) andZMO0843(P505H) via Genome resequencing-based SNPs (single nucleotide polymorphisms). A serial of differentially expressed genes (DEGs) were further identified as the potential contributors for stress tolerance via RNA-Seq sequencing, includingZMO0253andZMO_RS09265(type I secretion outer membrane protein),ZMO1941(Type IV secretory pathway protease TraF-like protein),ZMOr003andZMOr006(16S ribosomal RNA),ZMO0375andZMO0374(levansucrase) andZMO1705(thioredoxins). It enriched cellular process, followed by metabolic process and single-organism process for biological process. For KEGG analysis, the mutant was also referred to starch and sucrose metabolism, galactose metabolism and two-component system. Finally, but interestingly, it simultaneously achieved the enhanced stress tolerance capacity of aldehyde inhibitors and bioethanol fermentability in CSH for the mutantZ. mobilis.ConclusionsOf several candidate genetic changes, the mutantZ. mobilistreated with cold plasma was conferred upon the facilitated aldehyde inhibitors tolerance and bioethanol production. This work would provide a strain biocatalyst for the efficient production of lignocellulosic biofuels and biochemicals.