Mutlu Sariguzel Fatma, Berk Elife, Koc Ayse Nedret, Sav Hafize, Demir Gonca
Kayseri Education and Research Hospital, Kayseri, Turkey.
J Infect Dev Ctries. 2015 Aug 29;9(8):857-64. doi: 10.3855/jidc.5359.
The aim of study was to investigate the virulence factors of phospholipase, proteinase, esterase production and biofilm formation in Candida species isolated from patients with candidemia, and to assess their relationship with Candida genotypes derived after repetitive sequence-based polymerase chain reaction (rep-PCR) fingerprinting.
Fifty-two strains were identified to species level according to conventional methods and sequencing. The DiversiLab system was used for the genotyping. Enzyme activities and biofilm formation were evaluated using microbiological methods.
The 52 strains were identified as follows: 29 C. parapsilosis, 19 C. albicans, 2 C. glabrata, and 2 C. tropicalis. Phospholipase and proteinase activities were observed to have statistically significant differences between C. albicans and non-albicans Candida (NAC) strains (p < 0.05), with C. albicans strains showing higher virulence. Rep-PCR revealed eight major genotypes (A-H).The 19 C. albicans and the 33 non-albicans Candida isolates yielded seven (A-G) and four (A, B, C, H) genotypes, respectively. C. albicans strains were not shown to have a predominant genotype and showed higher phospholipase and proteinase activitiy than did NAC, regardless of genotype. Genotype H (52%) was the predominant genotype for the NAC including 27 C. parapsilosis strains, but the majority of strains showed low virulence.
NAC species were the most common causative agent for candidemia. Genotyping showed low transmission of C. albicans strains, but transmission of C. parapsilosis was high. In candidemia, several Candida virulence factors may be responsible at the same time. However, different genotypes of Candida strains showed different virulence activity.
本研究旨在调查从念珠菌血症患者中分离出的念珠菌属中磷脂酶、蛋白酶、酯酶产生及生物膜形成等毒力因子，并评估它们与基于重复序列的聚合酶链反应（rep-PCR）指纹图谱得出的念珠菌基因型之间的关系。
根据传统方法和测序将52株菌株鉴定到种水平。使用DiversiLab系统进行基因分型。采用微生物学方法评估酶活性和生物膜形成。
52株菌株鉴定结果如下：29株近平滑念珠菌、19株白念珠菌、2株光滑念珠菌和2株热带念珠菌。观察到白念珠菌与非白念珠菌（NAC）菌株之间磷脂酶和蛋白酶活性存在统计学显著差异（p < 0.05），白念珠菌菌株显示出更高的毒力。Rep-PCR揭示了8种主要基因型（A-H）。19株白念珠菌和33株非白念珠菌分离株分别产生了7种（A-G）和4种（A、B、C、H）基因型。白念珠菌菌株未显示出优势基因型，且无论基因型如何，其磷脂酶和蛋白酶活性均高于NAC。基因型H（52%）是NAC的优势基因型，包括27株近平滑念珠菌菌株，但大多数菌株显示出低毒力。
NAC菌种是念珠菌血症最常见的病原体。基因分型显示白念珠菌菌株传播率低，但近平滑念珠菌传播率高。在念珠菌血症中，几种念珠菌毒力因子可能同时起作用。然而，不同基因型的念珠菌菌株显示出不同的毒力活性。
