A mutant, TS-N-121 was obtained by mutation and plate screening from a parent strain Mycobacterium fortuitum MF2 , which could transform sterol into androstanedione as the main product.

从雄甾二酮的转化产生菌偶菌MF2出,经紫结合平板筛选,获得一株主要转化生产睾酮的突株TS-N-121。