Microenvironment of Mycobacterium smegmatis Culture to Induce Cholesterol Consumption Does Cell Wall Remodeling and Enables the Formation of Granuloma-Like Structures.

Microenvironment of Mycobacterium smegmatis Culture to Induce Cholesterol Consumption Does Cell Wall Remodeling and Enables the Formation of Granuloma-Like Structures.
Biomed Res Int. 2019;2019:1871239
Authors: Dos Santos ACD, Marinho VHS, Silva PHA, Macchi BM, Arruda MSP, da Silva EO, do Nascimento JLM, de Sena CBC
Abstract
Pathogenic species of mycobacteria are known to use the host cholesterol during lung infection as an alternative source of carbon and energy. Mycobacteria culture in minimal medium (MM) has been used as an in vitro experimental model to study the consumption of exogenous cholesterol. Once in MM, different species of mycobacteria start to consume the cholesterol and initiate transcriptional and metabolic adaptations, upregulating the enzymes of the methylcitrate cycle (MCC) and accumulating a variety of primary metabolites that are known to be important substrates for cell wall biosynthesis. We hypothesized that stressful pressure of cultures in MM is able to induce critical adaptation for the bacteria which win the infection. To identify important modifications in the biosynthesis of the cell wall, we cultured the fast-growing and nonpathogenic Mycobacterium smegmatis in MM supplemented with or without glycerol and/or cholesterol. Different from the culture in complete medium Middlebrook 7H9 broth, the bacteria when cultured in MM decreased growth and changed in the accumulation of cell wall molecules. However, t...

Source: Biomed Res - November 15, 2019 Category: Research Authors: Dos Santos ACD, Marinho VHS, Silva PHA, Macchi BM, Arruda MSP, da Silva EO, do Nascimento JLM, de Sena CBC Tags: Biomed Res Int Source Type: research