The study of multilocus sequence typing in Candida tropicalis

Abstract

Abstract:

Objective To study the dominant genotypes of multilocus sequence typing (MLST) about Candida tropicalis in Shanghai, China. Methods The clinical Candida tropicalis isolates were collected from Ruijin Hospital, Shanghai, China, and identified using morphological analysis on CHROMagar Candida and carbohydrate assimilation tests by API 20C AUX. Six housekeeping genes of Candida tropicalis were amplified and sequenced, and then the allelic profiles of the six gene sequences were obtained from the Candida tropicalis MLST database. The results were further analysed using the eBURST V3 package to determine the MLST clonal clusters. The phylogenetic tree was established using MEGA 6.0 software. Then the drug susceptibility tests were conducted to explore the relationship between strain resistance and genotype. Results There were 47 DSTs were obtained from 92 clinical Candida tropicalis isolates, from which 32 DSTs were new to the MLST database. DST507 and DST376 were the dominant genotypes, and they belong to the same clonal cluster. 21 of 27 clinical strains belonging to the dominant genotypes were azole-resistant strains. Conclusions MLST was a high-efficiency genotyping method for Candida tropicalis. DST507 and DST376 were the dominant genotypes to Candida tropicalis. It is necessary to monitor the spread of azole-resistant Candida tropicalis, especially clonal dissemination of DST507 and DST376 in the future.

Key words: Candida tropicalis, genotyping, MLST, DSTs

CLC Number:

R379.4

WANG Ying, XIANG Ming-jie, LIU Jin-yan, YE Shu-lai, ZHOU xin. The study of multilocus sequence typing in Candida tropicalis[J]. Chinese Journal of Mycology, 2018, 13(6): 321-326.

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