Use of green fluorescent protein labeled non-tuberculous mycobacteria to evaluate the activity quaternary ammonium compound disinfectants and antibiotics

Abstract

Although infections with NonTuberculous Mycobacteria have become less common in AIDS patients, they are important opportunistic infections after surgical procedures, likely because they are ubiquitous and not efficiently killed by many commonly used disinfectants. In Venezuela there have recently been many non-tuberculous mycobacteria soft tissue infections after minor surgical procedures, some apparently related to the use of a commercial disinfectant based on a Quaternary Ammonium Compound. We studied the activity of this and other quaternary ammonium compounds on different non-tuberculous mycobacteria by transforming the mycobacteria with a dnaA-gfp fusion and then monitoring fluorescence to gauge the capacity of different quaternary ammonium compounds to inhibit bacterial growth. The minimum inhibitory concentration varied for the different quaternary ammonium compounds, but M. chelonae and M. abscessus were consistently more resistant than M. smegmatis, and M. terrae more resistant than M. bovis BCG.

Mycobacterium vaccae Adaptation to Disinfectants and Hand Sanitisers, and Evaluation of Cross-Tolerance with Antimicrobials

“…Genes encoding for efflux pumps capable of expelling many quaternary ammonium compounds from the cells are responsible for a significant decrease in bacterial susceptibility [ 22 , 23 , 24 ]. In fact, the use of quaternary ammonium compounds has been linked to non-tuberculous mycobacteria infections following surgical procedures [ 25 , 26 ].…”

Easily applicable modifications to electroporation conditions improve the transformation efficiency rates for rough morphotypes of fast-growing mycobacteria

“…To test different electroporation conditions, plasmid pFPV27 was used as a DNA template, a broadly used vector in mycobacterial molecular biology [12,13]. This vector contains a kanamycin resistance gene as a selection marker and the gene for expression of green fluorescent protein (GFP), thus allowing the confirmation of positive transformants while distinguishing them from possible spontaneous resistant mutants.…”

The Research Gap in Non-tuberculous Mycobacterium (NTM) and Reusable Medical Devices

“…Comparative analyses have been performed between some Mycobacterium spp. for certain disinfectants [reviewed in Table 1; (11,13,14,(23)(24)(25)(26)(27)(29)(30)(31)]. These analyses have been limited in the number of organisms or pertain to specific types of disinfectants.…”

“…Therefore, in emergent NTM outbreaks, additional scientific literature concerning comparative resistance would provide helpful information about strains used for validation testing. Literature indicates that M. smegmatis , a rapid-growing Mycobacterium spp., is often less resistant to disinfectants ( 13 , 24 , 26 , 27 ). Because NTM vary in their susceptibility to some disinfectants, it is unclear whether testing medical device disinfection with M. smegmatis as a surrogate is applicable to clinically relevant NTM species ( 11 ).…”