RT Journal Article SR Electronic(1) A1 Brzostek, Anna A1 Śliwiński, Tomasz A1 Rumijowska-Galewicz, Anna A1 Korycka-Machała, Małgorzata A1 Dziadek, JarosławYR 2005 T1 Identification and targeted disruption of the gene encoding the main 3-ketosteroid dehydrogenase in Mycobacterium smegmatis JF Microbiology, VO 151 IS 7 SP 2393 OP 2402 DO https://doi.org/10.1099/mic.0.27953-0 PB Microbiology Society, SN 1465-2080, AB The catabolic potential for sterol degradation of fast-growing mycobacteria is well known. However, no genes or enzymes responsible for the steroid degradation process have been identified as yet in these species. One of the key enzymes required for degradation of the steroid ring structure is 3-ketosteroid Δ1-dehydrogenase (KsdD). The recent annotation of the Mycobacterium smegmatis genome (TIGR database) revealed six KsdD homologues. Targeted disruption of the MSMEG5898 (ksdD-1) gene, but not the MSMEG4855 (ksdD-2) gene, resulted in partial inactivation of the cholesterol degradation pathway and accumulation of the intermediate 4-androstene-3,17-dione. This effect was reversible by the introduction of the wild-type ksdD-1 gene into M. smegmatis ΔksdD-1 or overexpression of ksdD-2. The data indicate that KsdD1 is the main KsdD in M. smegmatis, but that KsdD2 is able to perform the cholesterol degradation process when overproduced., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.27953-0