Kong Nianqing, Shu Shenghuang, Zhang Cangyun, Li Chuyi, Luo Yongwen, Fang Shuying, Bi Shuilian
College of Food Science, Guangdong Pharmaceutical University, Zhongshan, Guangdong Province 528458, China.
College of Public Health, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province 510220, China.
J Appl Microbiol. 2023 Mar 1;134(3). doi: 10.1093/jambio/lxad030.
The ability to distinguish between Klebsiella pneumoniae strains is critical for outbreak investigations. A new typing method, intergenic region polymorphism analysis (IRPA), was developed, validated, and the discriminatory power was determined by comparison with multiple-locus variable-number tandem repeat analysis (MLVA) in this study.
This method is based on the idea that every IRPA locus (polymorphic fragment of intergenic regions present in one strain but not in other strains or different fragment sizes in other strains) could divide strains into different genotypes. A 9-loci IRPA scheme was designed to type 64 K. pneumoniae isolates. Five IRPA loci were identified that conferred the same level of discrimination as the 9-loci initially examined. Among these K. pneumoniae isolates, 7.81% (5/64), 6.25% (4/64), 4.96% (3/64), 9.38% (6/64), and 1.56% (1/64) were capsular serotypes K1, K2, K5, K20, and K54, respectively. The discriminatory power of the IRPA method was better than that of MLVA expressed in Simpson's index of diversity (SI) at 0.997 and 0.988, respectively. The congruent analysis of the IRPA method and MLVA showed moderate congruence between the two methods (AR = 0.378). The AW indicated that if IRPA data are availabl, one can accurately predict the MLVA cluster.
The IRPA method was found to have higher discriminatory power than MLVA and allowed for simpler band profile interpretation. The IRPA method is a rapid, simple, and high-resolution technique for molecular typing of K. pneumoniae.
区分肺炎克雷伯菌菌株的能力对于暴发调查至关重要。本研究开发并验证了一种新的分型方法——基因间区域多态性分析（IRPA），并通过与多位点可变数目串联重复分析（MLVA）比较来确定其鉴别力。
该方法基于这样的理念，即每个IRPA位点（一个菌株中存在而其他菌株中不存在的基因间区域多态性片段或其他菌株中不同的片段大小）可将菌株分为不同的基因型。设计了一个9位点的IRPA方案对64株肺炎克雷伯菌分离株进行分型。鉴定出5个IRPA位点，其鉴别力与最初检测的9个位点相同。在这些肺炎克雷伯菌分离株中，分别有7.81%（5/64）、6.25%（4/64）、4.96%（3/64）、9.38%（6/64）和1.56%（1/64）为荚膜血清型K1、K2、K5、K20和K54。IRPA方法的鉴别力优于MLVA，辛普森多样性指数（SI）分别为0.997和0.988。IRPA方法与MLVA的一致性分析表明两种方法之间存在中等一致性（AR = 0.378）。AW表明，如果有IRPA数据，就可以准确预测MLVA聚类。
发现IRPA方法比MLVA具有更高的鉴别力，并且条带图谱解释更简单。IRPA方法是一种用于肺炎克雷伯菌分子分型的快速、简单且高分辨率的技术。
