Insights into pbp Allelic mutations conferring resistance to Beta-Lactams in GBS isolates from India (ISSAD conference poster)
- 1 minBangalore, India 2023
I presented this project as a poster in the International Symposium on Streptococcus agalactiae Disease (ISSAD) conference held in Rio de Janeiro, Brazil
Introduction
Group B Streptococcus (GBS) is a significant pathogen causing infections in pregnant women and newborns. Despite the widespread use of β-lactam antibiotics (BLAs) for treatment, increasing antibiotic resistance poses a serious public health threat. This study aimed to investigate the role of mutations in the penicillin-binding protein (PBP) genes in conferring β-lactam resistance in GBS isolates from India.
Methods
This study utilized 128 GBS isolates collected from multiple centers across India. The isolates were identified and tested for Antibiotic Sensitivity using the VITEK 2 Compact system, followed by whole genome sequencing on the Illumina platform. PBP typing was done using a Nextflow pipeline by the Bentley group at The Wellcome Sanger Institute and the pbp alleles were characterized using the GATK tool to identify the mutations. Statistical analysis was performed to determine associations between mutations, resistance, and clonal complexes.
Results
Our analysis revealed a significant association between a specific mutation in the pbp2x gene, Q557E, and elevated resistance to BLAs, including penicillin, cefotaxime, and ceftriaxone. This mutation corresponds to a previously described resistance-conferring mutation in pneumococci. Additionally, we observed a high prevalence of the pbp2B allele, followed by pbp1A and pbp2x. Interestingly, one isolate lacking the pbp2x allele exhibited high levels of β-lactam resistance, suggesting the involvement of other factors in resistance.
Conclusion
Mutations in PBP genes, particularly the Q557E mutation in pbp2x, play a crucial role in conferring β-lactam resistance in GBS isolates from India. Understanding the mechanisms underlying these mutations is essential for developing effective strategies to combat GBS infections and prevent the spread of antibiotic resistance.
Poster
Srikanth Srinivas
Bioinformatics graduate student at University of Bristol | Former Bioinformatics Intern at Global Health Research Unit, CRL, KIMS