Regulation of alkane metabolism in Alcanivorax based on transcriptome and translatome

Abstract:

[Objective] Alcanivorax is a genus of dominant hydrocarbon-degrading bacteria in the marine environment, and the knowledge about the regulation mechanism of its alkane metabolism is limited. This study aims to decipher the regulation mechanism of alkane degradation by Alcanivorax at both transcriptional and translational levels. [Methods] The transcriptome and translatome data of A. dieselolei B5 grown in the medium with n-hexadecane as the sole carbon and energy source were obtained. The changes in the gene translation efficiency were calculated with sodium acetate as the control. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment was performed for the differentially translated genes (DTGs) and differential translation efficiency genes (DTEGs). [Results] Both the transcriptional and translational levels of the key genes involved in alkane metabolism were significantly up-regulated when A. dieselolei was grown on n-hexadecane. These key genes mainly encoded alkane monooxygenase, cytochrome P450 oxidase, alcohol dehydrogenase, and aldehyde dehydrogenase. KEGG enrichment analysis revealed that the up-regulated DTGs were involved in peptidoglycan biosynthesis, fatty acid degradation, chloroalkane degradation, oxidative phosphorylation, biofilm formation, etc. DTEGs were mainly involved in the biosynthesis of siderophore non-ribosomal peptides, oxidative phosphorylation, biosynthesis of unsaturated fatty acids, etc. The combined analysis of transcriptome and proteome data showed that A. dieselolei efficiently coordinated the transcription and translation processes to adapt to alkane oxidation. The gene expression level and translational efficiency showed a negative correlation under both culture conditions. The global protein regulators CsrA and sRNAs may be involved in post-transcriptional regulation of genes involved in alkane metabolism, leading to differences in the translational efficiency. [Conclusion] The combined analysis of transcriptome and translatome data suggested that post-transcriptional regulation was involved in the alkane metabolism of A. dieselolei. This study underpins further exploration of the post-transcriptional regulatory mechanisms controlling alkane metabolism.