Genotype analysis of Cryptococcus gattii species complex in Guangxi, southern China

Abstract

Abstract: Objective To explore the genotype characteristics and population structure characteristics of Cryptococcus gattii species complex in Guangxi, China, and to clarify the evolutionary relationship between Guangxi clinical isolates and global strains. Methods Clinical strains of Cryptococci isolated from clinically diagnosed patients with cryptococcosis between 2014 and 2018 were collected, and Cryptococci were preliminarily screened using CGB medium. Multi-site series typing (MLST) was used to determine genotype. Phylogenetic tree construction through MEGA7 software;Principal component analysis using R language. In vitro susceptibility test of antifungal agents was performed using m27-A3 protocol using microbroth dilution. Results Among the 120 strains of clinical Cryptococcus, 11 strains of Cryptococcus gattii species complex were isolated, 6 strains belonged to C.deuterogattii (AFLP6/VGⅡ), and 5 belonged to C.gattii sensus stricto (AFLP4/VGI). Strains of AFLP6/VGⅡ from Guangxi, were genetically variable and mainly originated and evolved from the Brazilian C.deuterogattii in South America. All isolates were sensitive to antifungal drugs. Conclusion Our study suggests that highly pathogenic AFLP6/VGⅡ may occur in Guangxi China, and effective national surveillance of C. gattii species complex is necessary.

Key words: Cryptococcus gattii, MLST, phylogenetic analysis, antifungal susceptibility

CLC Number:

R379.5

LI Bingkun, HUANG Chunyang, LI Xiuying, ZHENG Yanqing, PAN Kaisu, LIAO Wanqing, CAO Cunwei. Genotype analysis of Cryptococcus gattii species complex in Guangxi, southern China[J]. Chinese Journal of Mycology, 2021, 16(2): 84-89.

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