Growth and cholesterol oxidation by Mycobacterium species in Tween 80 medium

Abstract

Mycobacterium strain DP was isolated from marine coastal sediment and tested for its ability to oxidize cholesterol in Tween 80-cholesterol (2.59 mM) medium. Strain DP degraded cholesterol to 4-cholesten-3-one (cholestenone), 4-androsten-3,17-dione (AD), 1,4-androstadien-3,17-dione (ADD), testosterone, and 1-dehydrotestosterone (DHT). Cholesterol disappeared in about 4 days. Cholestenone, AD, testosterone, and DHT accumulations were transient with peak concentrations of 300, 600, 30 to 40, and 21 tLM. ADD production peaked after 6 days with a concentration of 1,100 ,uM. Peak ADD concentrations and production rates compared well with those reported for strain NRRL B3683 on cyclodextrin medium. Tween 80 medium was superior to finely dispersed cholesterol particles for both strains. In comparison, NRRL B3683 (patented for its ability to accumulate AD and ADD) on Tween 80 medium transiently accumulated more AD (-1,000 ,uM) than did strain DP, but ADD accumulations (200 ,uM) were significantly lower than those for strain DP. Strain DP could be adapted to grow on ADD, which was initially inhibitory at 3.25 mM. ADD-adapted strain DP cultures produced approximately four times as much DHT from ADD than unadapted cultures did from cholesterol, showing that additional manipulation might enhance testosterone production. We believe that ADD toxicity might account for the low ADD accumulations by NRRL B3683 in Tween 80 medium.

Catabolism and biotechnological applications of cholesterol degrading bacteria

“…Some of the microorganisms used to produce cholestenone from cholesterol are Mycobacterium sp. (Smith et al, 1993), R. equi (Ahmed and Johri, 1993), Escherichia (Panchishina, 1992), Nocardia rubra (Osipowicz et al, 1992), A. simplex (Liu et al, 1994a), R. erythropolis (Jadoun and Bar, 1993), R. equi (Myamato and Toyoda, 1994), Agrobacterium sp. M4 (Mahato and Garai, 1997;Yazdi et al, 2000).…”

Evolutionary innovation: a bone‐eating marine symbiosis

“…Comparisons were made between root homogenate enrichments and those attempted with inoculants from decaying whale bones and surrounding sediment. Liquid cultures were made with filtered seawater and one of the following substrates: 2.5 mM cholesterol (with 0.1% Tween 20), collagen (0.5% w/ v, 0.1% Tween 20), fatty acids (1 mM) and fish oil (1:1000 v/ v) (Smith et al, 1993;DSMZ, 2004). Agar plates were made with artificial seawater (30 g Instant Ocean l -1 ) with 2% agarose and the following substrate levels: 2.5 mM cholesterol (with 0.1% Tween 20), collagen (0.1% w/v), fatty acids (5 mM) and fish oil (1:1000 v/v).…”

Engineering Mycobacterium smegmatis for testosterone production

“…During the course of this work, Dlugovitzky et al (2015) have shown that Mycobacterium smegmatis PTCC 1307 was able to produce TS and other estrogens from tritiated precursors. However, TS has not been detected as a metabolic intermediate when M. smegmatis mc 2 155 is cultured in the presence of phytosterols or cholesterol, neither in the wild-type strain nor in the AD-producing strain (Gal an et al, unpublished), unlike in other mycobacterial species (Wang et al, 1982;Smith et al, 1993;Egorova et al, 2002b). This observation suggests that M. smegmatis mc 2 155 does not contain a functional gene encoding a 17b-HSD or at least, it is not induced in the presence of these compounds.…”