Abstract：
Interactions between C. albicans and the microbiota play an important role in maintaining the balance between commensal and pathogenic organisms. Although the exact role of bacteria in reducing the pathogenicity of yeast remains poorly understood, a few examples have been documented so far: probiotics administration effectively reduces the formation of biofilm and bacterial metabolites inhibit the formation of hyphae. The aim of the study was to analyze C. albicans virulence levels based on the changes in the morphological structure and enzymatic profile in experimental cultures mixed with Escherichia coli. Viable cell abundance, cell pleomorphism and enzymatic profile were analyzed in single and mixed cultures (C. albicans + E. coli). The microscope analysis showed a large decrease in the number of viable C. albicans cells in mixed cultures with E. coli from 485.3±132.1 immediately after the establishment of the culture to 238.1±71.2 after an hour of incubation and 24.4±5.4 after 24 h. The length of C. albicans cells differed significantly between the single-species cultures and the mixed cultures for 24 h. Our present findings indicate a significant reduction in the secretion of several enzymes by fungi following contact with E. coli, including acid phosphatase, N-acetyl-β-glucosaminidase, naphthol-AS-BI-phosphohydrolase and leucine arylamidase. The interactions between fungi and bacteria appear to be extremely complex. On the one hand, during C. albicans with E. coli co-incubation, the bacteria stimulated the elongation of yeast cells, leading to the formation of a filamentous form; however, the number of yeast cells and their enzymatic activity decreased significantly. Therefore, it can be concluded that while E. coli stimulates some pathogenic properties, e.g. cell elongation, it also inhibits other virulence features, e.g. enzymatic activity of C. albicans.
摘要：
白色念珠菌与微生物群之间的相互作用在维持共生生物和病原生物之间的平衡中起着重要作用。尽管细菌在降低酵母致病性中的确切作用仍然知之甚少，到目前为止，已经记录了一些例子:益生菌有效地减少了生物膜的形成，细菌代谢物抑制了菌丝的形成。该研究的目的是根据与大肠杆菌混合的实验培养物中的形态结构和酶谱的变化来分析白色念珠菌的毒力水平。活细胞丰度，在单一和混合培养中分析了细胞多态性和酶谱(C.白色念珠菌+大肠杆菌）。显微镜分析显示，与大肠杆菌混合培养物中的活白色念珠菌细胞数量大幅减少，从培养建立后的485.3±132.1减少到孵育一小时后的238.1±71.2和24小时后的24.4±5.4。单物种培养物和混合培养物24小时的白色念珠菌细胞长度显着不同。我们目前的发现表明，与大肠杆菌接触后，真菌分泌的几种酶显着减少。包括酸性磷酸酶,N-乙酰-β-氨基葡萄糖苷酶,萘酚-AS-BI-磷酸水解酶和亮氨酸芳基酰胺酶。真菌和细菌之间的相互作用似乎非常复杂。一方面,在白色念珠菌与大肠杆菌共孵育期间，细菌刺激酵母细胞的伸长,导致丝状形式的形成；然而，酵母细胞数量及其酶活性显著下降。因此,可以得出结论，虽然大肠杆菌刺激一些致病特性，例如细胞伸长，它还抑制其他毒力特征，例如白色念珠菌的酶活性。
