Whole-Genome Sequencing-Based Characterisation of Clinically Relevant Mycobacterium abscessus Complex Isolates from...

Area of Science:

• Microbiology
• Genomics
• Antimicrobial Resistance

Background:

• Mycobacterium abscessus complex causes difficult-to-treat infections.
• Intrinsic antimicrobial resistance and genomic heterogeneity complicate treatment.
• This study focused on pulmonary M. abscessus isolates from India.

Purpose of the Study:

• To characterize clinical pulmonary M. abscessus isolates from India.
• To analyze genomic, phylogenetic, and antimicrobial resistance profiles using whole-genome sequencing (WGS).
• To investigate the genetic basis of antimicrobial resistance, particularly macrolide resistance.

Main Methods:

• Whole-genome sequencing (WGS) of five clinical pulmonary M. abscessus isolates.
• Quality filtering, reference-guided alignment, and consensus generation.
• Genome annotation, variant analysis, and antimicrobial resistance gene detection using CARD database.

Main Results:

• High-quality sequencing data generated with excellent Q30 values and genome coverage.
• Significant isolate-level genomic heterogeneity observed.
• blaMab gene detected in all isolates, supporting intrinsic beta-lactam resistance.
• erm(41) gene detected in one isolate (LIN), correlating with inducible macrolide resistance.

Conclusions:

• WGS revealed conserved genomic features alongside measurable heterogeneity in Indian M. abscessus isolates.
• blaMab gene confers intrinsic beta-lactam resistance.
• erm(41) gene is associated with inducible macrolide resistance in M. abscessus.