Hii Shirley Yi Fen, Ahmad Norazah, Hashim Rohaidah, Liow Yii Ling, Abd Wahab Muhammad Adib, Mohd Khalid Mohd Khairul Nizam
Bacteriology Unit, Infectious Diseases Research Centre, Institute for Medical Research, Jalan Pahang, 50588, Kuala Lumpur, Wilayah Persekutuan Kuala Lumpur, Malaysia.
Molecular Diagnostics and Protein Unit, Specialised Diagnostics Centre, Institute for Medical Research, Jalan Pahang, Kuala Lumpur, 50588, Wilayah Persekutuan Kuala Lumpur, Malaysia.
BMC Res Notes. 2018 Oct 25;11(1):760. doi: 10.1186/s13104-018-3868-6.
There is a lack of study in Corynebacterium diphtheriae isolates in Malaysia. The alarming surge of cases in year 2016 lead us to evaluate the local clinical C. diphtheriae strains in Malaysia. We conducted single nucleotide polymorphism phylogenetic analysis on the core and pan-genome as well as toxin and diphtheria toxin repressor (DtxR) genes of Malaysian C. diphtheriae isolates from the year 1986-2016.
The comparison between core and pan-genomic comparison showed variation in the distribution of C. diphtheriae. The local isolates portrayed a heterogenous trait and a close relationship between Malaysia's and Belarus's, Africa's and India's strains were observed. A toxigenic C. diphtheriae clone was noted to be circulating in the Malaysian population for nearly 30 years and from our study, the non-toxigenic and toxigenic C. diphtheriae strains can be differentiated significantly into two large clusters, A and B respectively. Analysis against vaccine strain, PW8 portrayed that the amino acid composition of toxin and DtxR in Malaysia's local strains are well-conserved and there was no functional defect noted. Hence, the change in efficacy of the currently used toxoid vaccine is unlikely to occur.
马来西亚对白喉棒状杆菌分离株的研究较少。2016年病例数的惊人激增促使我们对马来西亚当地临床白喉棒状杆菌菌株进行评估。我们对1986 - 2016年马来西亚白喉棒状杆菌分离株的核心基因组和泛基因组以及毒素和白喉毒素阻遏物（DtxR）基因进行了单核苷酸多态性系统发育分析。
核心基因组和泛基因组比较显示白喉棒状杆菌的分布存在差异。本地分离株呈现出异质性特征，并且观察到马来西亚菌株与白俄罗斯、非洲和印度的菌株之间存在密切关系。一种产毒白喉棒状杆菌克隆在马来西亚人群中传播了近30年，从我们的研究来看，无毒和产毒白喉棒状杆菌菌株可明显分为两个大簇，分别为A簇和B簇。与疫苗株PW8的分析表明，马来西亚本地菌株中毒素和DtxR的氨基酸组成保守，未发现功能缺陷。因此，目前使用的类毒素疫苗效力不太可能发生变化。
