Pneumococcal transposon profiling associated with macrolide, tetracycline, and chloramphenicol resistance from carriage isolates of serotype 19F in Indonesia.

Genetic evolution of resistance due to mutations and transposon insertions is the primary cause of antimicrobial resistance in Streptococcus pneumoniae. Resistance to macrolide, tetracycline, and chloramphenicol is caused by the insertion of specific genes that carried by transposon (Tn). This study aims to analyze transposon profiling associated with macrolide, tetracycline, and chloramphenicol resistance from carriage isolates of S. pneumoniae serotype 19F in Indonesia. S. pneumoniae serotype 19F isolates were collected from nasopharyngeal swab specimens from different regions in Indonesia. Genomic DNA was extracted from sixteen isolates and whole genome sequencing was performed on Illumina platform. Raw sequence data were analyzed using de novo assembly by ASAP and Microscope server. The presence of transposons was identified with detection of int and xis genes and visualized by pyGenomeViz. The genome size of S. pneumoniae ranges from 2,040,117 bp to 2,437,939 bp, with a GC content of around 39 %. ST1464 (4/16) and ST271 (3/16) were found as the predominant sequence type among isolates. Tn2010 was the most common transposon among S. pneumoniae serotype 19F isolates (7/16) followed by Tn2009 (4/16), and Tn5253 (3/16). We identified two deletion sites within the tetM gene (2 bp and 58 bp) that confer tetracycline susceptibility from one isolate. This study suggests that genomic analysis can be employed for the detection and surveillance of antimicrobial resistance genes among S. pneumoniae strains isolated from various regions in Indonesia.