Abstract
It has been reported that lateral gene transfer (LGT) events among Mycobacteroides abscessus strains are prevalent. The hsp65 gene, a chronometer gene for bacterial phylogenetic analysis, is resistant to LGT events, particularly among mycobacterial strains, rendering the hsp65-targeting method the most widely used method for mycobacterial detection. To determine the prevalence of M. abscessus strains that are subject to hsp65 LGT, we applied rpoB typing to 100 clinically isolated Korean strains of M. abscessus that had been identified by hsp65 sequence analysis. The analysis indicated the presence of 2 rough strains, showing a discrepancy between the 2 typing methods. MLST analysis based on the partial sequencing of seven housekeeping genes, erm(41) PCR and further hsp65 PCR-restriction enzyme and polymorphism analysis (PRA) were conducted to identify the two strains. The MLST results showed that the two strains belong to M. abscessus subsp. massiliense and not to M. abscessus subsp. abscessus, as indicated by the rpoB-based analysis, suggesting that their hsp65 genes are subject to LGT from M. abscessus subsp. abscessus. Further analysis of these strains using the hsp65 PRA method indicated that these strains possess a PRA pattern identical to that of M. abscessus subsp. abscessus and distinct from that of M. abscessus subsp. massiliense. In conclusion, we identified two M. abscessus subsp. massiliense rough strains from Korean patients with hsp65 genes that might be laterally transferred from M. abscessus subsp. abscessus. To the best of our knowledge, this is the first demonstration of possible LGT events associated with the hsp65 gene in mycobacteria. Our results also suggest that there is the potential for misidentification when the hsp65-based protocol is used for mycobacterial identification.
Highlights
Growing mycobacteria (RGM) are ubiquitous organisms that have gained increasing attention as important human pathogens [1, 2]
We recently identified six M. abscessus subsp. massiliense strains isolated from Korean patients in which the rpoB gene was laterally transferred from M. abscessus subsp. abscessus [22], suggesting the potential for misidentification when the rpoB tying method is used to the differentiate among M. abscessus strains
Identification of two M. abscessus strains for which discordant results were obtained in hsp65 and rpoB sequence analyses
Summary
Growing mycobacteria (RGM) are ubiquitous organisms that have gained increasing attention as important human pathogens [1, 2]. Among RGMs, infections due to the Mycobacteroides abscessus strains have shown increased worldwide clinical importance, and their incidence in cystic fibrosis patients has increased [3]. The taxonomy of M. abscessus strains remains problematic. These strains are divided into two subspecies, M. abscessus subsp. Abscessus (the former species Mycobacteroides abscessus) and M. abscessus subsp. Bolletii was proposed to combine the two former species, M. massiliense and M. bolletii [10, 11]. Recent phylogenomics and comparative genome analyses on 150 genomes of Mycobacterium species revealed that the genus of Mycobacterium was divided four novel genera. In the case of M. abscessus-chelonae complex, their genus was emended into Mycobacteroides [15]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
