Fig. 1

Rational disruption of the mycolic acid synthesis disturbed the sterol conversion. a Profile of the mycolic acid synthesis pathway in mycobacteria cells [18]. FAS-I, fatty acid synthase I; FabD, malonyl CoA-acyl carrier protein (ACP) transacylase; FabH, β-ketoacyl-ACP synthase III; MabA, β-ketoacyl-ACP reductase; HadABC, β-hydroxyacyl-ACP dehydratase subunits A, B and C; InhA, enoyl-ACP reductase; KasA, β-ketoacyl-ACP synthase 1; KasB, β-ketoacyl-ACP synthase 2; PcaA, proximal cyclopropanation of alpha-MAs enzyme; MmaA1-4, methyl mycolic acid synthase; CmaA2, cyclopropyl mycolic acid synthase; AccD4, propanoyl-CoA carbon dioxide ligase; AccD5, propionyl-CoA carboxylase; FadD32, long-chain-fatty-acid-AMP synthetase, Pks13, polyketide synthase. b Transcription changes in the dispensable genes involved in mycolic acid synthesis. All data indicate log2 fold change ratio of the gene expression. Mn, the wild type M. neoaurum was cultured in MYC/02 medium. Mn + C, the wild type strain was cultivated in the presence of phytosterol. MnΔkstD1 + C, the primary 9-OHAD-producing strain MnΔkstD1 was cultured in MYC/02 medium with phytosterol addition. Data were from two independent analyzes. c The alternation of sterol utilization rate caused by the targeted gene deletion in 72 h sample time. Data represent the mean standard deviation of three measurements