Department of Clinical Microbiology, Christian Medical College, Vellore, India.
Department of Child Health, Christian Medical College, Vellore, India.
Mol Biol Rep. 2021 Apr;48(4):3265-3276. doi: 10.1007/s11033-021-06353-6. Epub 2021 Apr 19.
The emergence of multi drug resistant clone CC320 serotype19F/19A and their capsular (cps) antigenic variants due to selective pressures such as vaccine had been reported worldwide. Hence, it is important to identify the prevalent clones, sequence types and cps variants of serotype 19F/19A in India, where PCV13 has been recently introduced. Multi-locus sequence typing (MLST) was performed for all (n = 21) invasive S. pneumoniae isolates of serotype 19A (n = 5) and 19F (n = 16) collected between the years 2012 and 2018 from children less than 5 years. The genome characterization by whole genome sequencing for the Sequence types (STs) 320 and 271(n = 7) were performed and compared with another six Indian WGSs of similar STs available from the GPS platform. The predominant STs in the serotype 19F/19A study isolates were of CC320: ST 320, 236 and 271, associated with PMEN clone Taiwan-14. The WGSs of CC320 study isolates showed high genomic similarity to the Taiwan-14 clone, and the penicillin binding protein (PBP) amino acid sequence similarity was 100% for PBP1A, 93% for PBP 2B and 2X. Whilst PBP comparison with other global MDR ST320 strains revealed that the ST320 clones in India are of low-level penicillin resistance. The presence of a few ST320/19A/19F invasive isolates with high similarity to the Taiwan clone suggests slow and gradual expansion of Taiwan-14 associated CC320 clones in India. Since serotype 19F/19A is covered by PCV13 vaccine, the expansion of 19F/19A cones with non-PCV13 vaccine serotype in India should be monitored.
由于疫苗等选择性压力的存在，全球范围内已经报道了多药耐药克隆 CC320 血清型 19F/19A 及其荚膜（cps）抗原变体的出现。因此，确定印度流行的克隆、序列类型和血清型 19F/19A 的 cps 变体非常重要，印度最近引入了 PCV13。对 2012 年至 2018 年间收集的来自 5 岁以下儿童的血清型 19A（n=5）和 19F（n=16）侵袭性肺炎链球菌分离株进行了多基因座序列分型（MLST）。对 7 个序列类型（ST）320 和 271 的基因组特征进行了全基因组测序，并与 GPS 平台上提供的另外 6 个具有类似 ST 的印度 WGS 进行了比较。血清型 19F/19A 研究分离株中主要的 ST 是 CC320：ST320、236 和 271，与 PMEN 克隆台湾 14 相关。CC320 研究分离株的 WGS 与台湾 14 克隆具有高度的基因组相似性，青霉素结合蛋白（PBP）氨基酸序列相似性为 100%的 PBP1A、93%的 PBP2B 和 2X。而与其他全球 MDR ST320 菌株的 PBP 比较表明，印度的 ST320 克隆具有低水平的青霉素耐药性。少数 ST320/19A/19F 侵袭性分离株与台湾克隆具有高度相似性，表明与台湾 14 相关的 CC320 克隆在印度的缓慢而逐渐扩张。由于血清型 19F/19A 被 PCV13 疫苗覆盖，印度应该监测非 PCV13 疫苗血清型 19F/19A 克隆的扩张。
