Effect of Zinc on Cell Morphogenesis of Candida dubliniensis

Abstract

Background and objective: Candida dubliniensis is a budding yeast that is capable of switching from yeast to hypha to penetrate epithelium and may therefore be an important virulence factor. Yeast and hyphae are benefit to particular situation. Since zinc is found to be one factor that correlates with candidiasis. This provided informative data to our study. Objective of this study is to investigate whether zinc influences on morphogenesis of C. dubliniensis.

Method: Germ tube formation in human serum was used as a test method. Thirty isolates of C. dubliniensis were incubated in human serum (control), human serum supplemented with zinc (zinc repleted condition), and human serum supplemented with zinc chelator (TPEN) (zinc depleted condition) at 37°C for two hrs. After incubation, germ tube cells were counted under a light microscope in total 20 high power fields for each condition. C. albicans was used as positive control.

Result: The result showed that germ tube was normally formed in human serum and human serum supplemented with zinc, no significant difference between both conditions. Conversely, germ tube was significantly inhibited when zinc was depleted. In the body, zinc ion is normally bound to proteins in blood stream to control the growth of harmful pathogen but this situation is also favorable for yeast to spread throughout the body system if it is able to invade the vessel. This result was one useful information showed that zinc influenced on morphogenesis and can be integrated to candidiamia that low zinc in blood stream may provide easier moving for this dimorphic organism causing candidiamia secondary to tissue invasion by yeast-hypha transition.

Conclusion: Germ tube formation was significantly inhibited in zinc depleted condition when compared with in zinc-rich and control conditions.