Polymorphism analysis of virulence-related genes among Candida tropicalis isolates  

作　　者：Li-Juan Zhang Shuan-Bao Yu Wen-Ge Li Wen-Zhu Zhang Yuan WU Jin-Xing Lu 

机构地区：[1]Oepartment of Gynecology,Beijing Obstetrics and Gynecology Hospital,Capital Medical University,Beijing 100026,China [2]State Key Laboratory of Infectious Disease Prevention and Control,Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases,National Institute for Communicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention,Beijing 102206,China

出　　处：《Chinese Medical Journal》2019年第4期446-453,共8页中华医学杂志（英文版）

基　　金：the National Natural Science Foundation of China (Youth Project No.81301409);the National Sci-Tech Key Project (No.2013ZX10004203-002).

摘　　要：Background: Adhesion, biofilm formation, yeast-hyphal transition, secretion of enzymes, and hemolytic activity are all considered important factors in Candida tropicalis infection. However, DNA sequence data for this pathogen are limited. In this study, the polymorphism and heterogeneity of genes agglutinin-like sequences (ALS)2, Lipase (LIP)1, LIP4, and secretory aspartyl proteinase tropicalis (SAPT)1-4 as well as the relationship between phenotype and genotype were analyzed. Methods: This study started in August 2013, and ended in July 2017. The complete length of ALS2, LIP1, LIP4, and SAPT1-4 of 68 clinical C. tropicalis isolates was sequenced. Single nucleotide polymorphisms (SNPs) as well as insertions and deletions (indels) were identified within these genes. In addition, phenotypic characteristics of the virulent factors, including adhesion and the secretion of aspartyl proteinases and phospholipases, were determined. Results: There were 73, 24, 17, 16, 13, and 180 SNPs in the genes LIP1, LIP4, SAPT1, SAPT2, SAPT3, and SAPT4, respectively. Furthermore, 209 SNPs were identified in total for the gene ALS2. Interestingly, large fragment deletions and insertions were also found in ALS2. Isolate FXCT 01 obtained from blood had deletions on all 4 sites and showed the lowest adhesion ability on the polymethylpentene surface. In addition, isolates with deletions in the regions 1697 to 1925 and 2073 to 2272 bp displayed relatively low abilities for adhesion and biofilm formation, and this phenotype correlated with the deletions found in ALS2. LIP1, SAPT4, and ALS2 displayed great heterogeneity among the isolates. Large deletions found in gene ALS2 appeared to be associated with the low ability of adhesion and biofilm formation of C. tropicalis. Conclusion: This study might be useful for deeper explorations of gene function and studying the virulent mechanisms of C. tropicalis.

关 键 词：CANDIDA TROPICALIS Virulence-related GENES PHYLOGENETIC analysis GENE ALS GENE LIP GENE SAP 

分 类 号：R[医药卫生]