Liu Dan, He Shu-Min, Zhu Xiao-Zhen, Liu Li-Li, Lin Li-Rong, Niu Jian-Jun, Yang Tian-Ci
Center of Clinical Laboratory, Zhongshan Hospital, School of Medicine, Xiamen University, Xiamen, China.
Institute of Infectious Disease, School of Medicine, Xiamen University, Xiamen, China.
Front Cell Infect Microbiol. 2021 Feb 19;10:618747. doi: 10.3389/fcimb.2020.618747. eCollection 2020.
In total, 49 clinical samples were analyzed using two typing schemes, Enhanced Centers for Disease Control and Prevention (ECDC) and multilocus sequence typing (MLST), to describe the molecular characteristics of circulating isolates in Xiamen between 2016 and 2017. In addition, genetic mutations potentially related to antibiotic resistance of were also analyzed. Forty five samples were fully typed by ECDC, and 14 different subtypes were detected. The most common subtype was 16d/f (24.4%), followed by 14d/f (20.0%). All forty nine samples were successfully typed by MLST, while only four allelic profiles were identified, including three SS14-like profiles and one Nichols-like profile. Among them, the major allelic profile was 1.1.8 (85.7%). Interestingly, the allelic profile 1.3.1 widespread in Europe and North America was not detected in this region. Additionally, A2058G mutation in 23S rRNA was found in all detectable samples (38/38), and no mutation in 16S rRNA was observed (36/36). Four non-synonymous single-nucleotide polymorphisms in penicillin-binding protein genes were found in the 35 samples eligible for Sanger sequencing. Among them, the variant in (P564I) can only be found in the SS14-like isolates. Homoplastic changes in (I415F/I415M) and (A506V/A506T) were found. Moreover, the variant A506V and the variant A506T separately appeared in the SS14-like isolates and Nichols-like isolates, respectively. This study showed that the genotypes of isolates in Xiamen between 2016 and 2017 were different from those in other geographic areas. The resistance-related variants of isolates identified in this study could provide awareness for clinicians in the treatment of syphilis.
总共使用两种分型方案，即强化疾病控制与预防中心（ECDC）分型方案和多位点序列分型（MLST），对49份临床样本进行分析，以描述2016年至2017年厦门地区流行分离株的分子特征。此外，还分析了可能与抗生素耐药性相关的基因突变。45份样本通过ECDC进行了完全分型，检测到14种不同亚型。最常见的亚型是16d/f（24.4%），其次是14d/f（20.0%）。所有49份样本均通过MLST成功分型，仅鉴定出4种等位基因谱，包括3种SS14样谱和1种Nichols样谱。其中，主要的等位基因谱是1.1.8（85.7%）。有趣的是，在该地区未检测到在欧洲和北美广泛存在的等位基因谱1.3.1。此外，在所有可检测样本（38/38）中均发现23S rRNA中的A2058G突变，而在16S rRNA中未观察到突变（36/36）。在35份符合桑格测序条件的样本中，发现青霉素结合蛋白基因中有4个非同义单核苷酸多态性。其中，tprK（P564I）中的变体仅在SS14样分离株中发现。发现tprK（I415F/I415M）和tprE（A506V/A506T）中的同源性变化。此外，变体A点突变506V和变体A点突变506T分别出现在SS14样分离株和Nichols样分离株中。本研究表明，2016年至2017年厦门地区梅毒螺旋体分离株的基因型与其他地理区域不同。本研究中鉴定出的梅毒螺旋体分离株的耐药相关变体可为临床医生治疗梅毒提供参考。
