First Detection of Ketoreductase in the Genome of Rapid Growing Environmental Mycobacterial Strains in Cote D’ivoire

Mycobacterium ulcerans (MU), the causative agent of Buruli ulcer (BU), skin disease, is considered to be an environmental pathogen. The pathogenic virulence of MU is being linked to the expression of toxin called Mycolactone. The ketoreductase (KR) gene, is one of the synthesis genes of mycolactone enzymes previously found in M. ulcerans. Genetic analyses using variable number tandem repeats (VNTR) and mycobacterial interspersed repetitive units (MIRU) have shown high diversity in M. ulcerans and in mycolactone producing Mycobacteria (MPMs).

Aim: The purpose of this study is to detect ketoreductase gene in the genome of environmental mycobacteria strain, apart the M. ulcerans, from aquatic environments in Côte d’Ivoire.

Place and Duration of the Study: The analysis of the samples took place in the laboratories of Institut Pasteur de Côte d’Ivoire in Abidjan City between June 2014 and December 2015. Sampling was done in some hypoendemic and hyperendemic sites of Buruli Ulcer of Côte d’Ivoire.

Methodology: A total of 473 samples were collected comprising of 251 waters and 222 sediments based on sampling sites. PCR diagnostics using IS2404 and KR were performed on strains.

Results: 20% fast growing isolated mycobacteria species including Mycobacterium mucogenicum,Mycobacterium peregrinum and Mycobacterium sp. was found carrying the IS2404 gene previously found in M. ulcerans. 9.23% of strains carried the ketoreductase (KR) genes, one of the synthesis of mycolactone enzyme.

Conclusion: The results of this study proved the existence of ketoreductase (KR) genes in rapidly- growing mycobacteria. This study is one of the steps taken in order to understand different skin infections encountered in Côte d’Ivoire.