Engineering Mycobacterium smegmatis for testosterone production

Abstract

SummaryA new biotechnological process for the production of testosterone (TS) has been developed to turn the model strain Mycobacterium smegmatis suitable for TS production to compete with the current chemical synthesis procedures. We have cloned and overexpressed two genes encoding microbial 17β‐hydroxysteroid: NADP 17‐oxidoreductase, from the bacterium Comamonas testosteroni and from the fungus Cochliobolus lunatus. The host strains were M. smegmatis wild type and a genetic engineered androst‐4‐ene‐3,17‐dione (AD) producing mutant. The performances of the four recombinant bacterial strains have been tested both in growing and resting‐cell conditions using natural sterols and AD as substrates respectively. These strains were able to produce TS from sterols or AD with high yields. This work represents a proof of concept of the possibilities that offers this model bacterium for the production of pharmaceutical steroids using metabolic engineering approaches.

Molecular characterization of a new gene cluster for steroid degradation in Mycobacterium smegmatis

“…It has been demonstrated that M. smegmatis mc 2 155 is able to transport efficiently different C‐19 steroids (e.g. AD) (Fernández‐Cabezón et al ., 2017) and hence, the inability to use C‐19 steroids as carbon sources cannot be due to transport problems. Therefore, we ascribed this behaviour to the fact that the cholesterol pathway might be more tightly regulated in M. smegmatis mc 2 155 than in other C‐19 steroid degrading bacteria, and thus, these compounds might be metabolized only after the complete activation of the kstR regulon that only responds to some CoA‐derivatives of the side chain as inducers (García‐Fernández et al ., ; Ho et al ., ).…”

Statistical Optimization of Culture Conditions for Protein Production by a Newly Isolated Morchella fluvialis

“…Hasan [54] and Fernández Cabezón et al [55] reported that various fungi species like Aspergillus flavus, A. ochraceus, Gibberella zeae, Cladosporium cladosporioides, Penicillium funiculosum, and P. rubrum were capable of producing high amount of hormones. Many research studies indicated that gut microflora had a great role in estrogen and phytoestrogen production [56][57][58].…”

Biosynthesis and Industrial Production of Androsteroids

“…Engineered strains able to produce testosterone by biotransformation of phytosterols were recently established in Mycobacteria [ 25 ]. A Mycobacterium smegmatis with stably overexpressed HSD3B from Comamonas testosteroni and from Cochliobolus lunatus was used ( Figure 2 ), however significant amounts of testosterone were not yet obtained.…”