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Comparison of biochemical characterisation of ICRC bacilli with M. leprae: effect of substrate alteration in the
Abstract:
ICRC-bacilli strain C-44 when grown in Dubos medium of its equivalent, express M. avium taxonomic biochemical characters. Assuming that difference in characters of M. leprae and ICRC bacilli, could be due to 'in vivo' and 'in vitro' milieu, we altered the substrates in the medium. The bacilli grow well in the new medium containing selenium, ferric nitrate, magnesium chloride and deleting Tween 80. The ICRC strain C-44 grown in new medium expressed characters: 9/10 similarity with M. leprae. The 10 day tween hydrolysis reaction in weak but positive. It is probable that 'M. leprae culture isolate', may have acquired 'in vitro' growth potential by recombination with M. avium, an ubiquitous mycobacterium. The M. leprae culture isolate thus may express some characters of both M. leprae and M. avium.
Insights
Researchers modified growth medium for ICRC bacilli strain C-44, achieving 9/10 similarity to Mycobacterium leprae. This suggests M. leprae may acquire in vitro growth via recombination with M. avium.
Area of Science:
- Microbiology
- Mycobacterial research
Background:
- The ICRC bacilli strain C-44 exhibits biochemical characteristics of Mycobacterium avium when cultured in standard media.
- Differences observed between Mycobacterium leprae and ICRC bacilli may stem from in vivo versus in vitro environmental factors.
Purpose of the Study:
- To investigate the influence of altered culture media on the biochemical expression of ICRC bacilli strain C-44.
- To determine if modified growth conditions can induce phenotypic characteristics resembling Mycobacterium leprae.
Main Methods:
- Culturing ICRC bacilli strain C-44 in a modified Dubos medium incorporating selenium, ferric nitrate, and magnesium chloride, while omitting Tween 80.
- Assessing the biochemical characteristics of the cultured bacilli.
Main Results:
- ICRC bacilli strain C-44 demonstrated robust growth in the modified medium.
- The modified culture conditions resulted in the expression of biochemical characters showing a 9/10 similarity to Mycobacterium leprae.
- A weak but positive 10-day Tween hydrolysis reaction was observed.
Conclusions:
- The study suggests that modifying the in vitro environment can significantly alter the phenotypic expression of mycobacterial strains.
- It is hypothesized that Mycobacterium leprae isolates may gain in vitro growth capabilities through recombination with Mycobacterium avium.
- This recombination could explain the expression of mixed M. leprae and M. avium characteristics in cultured isolates.