Effect of plagiochin E, an antifungal macrocyclic bis（bibenzyl）, on cell wall chitin synthesis in Candida albicans  

作　　者：Xiu-zhen WU Ai-xia CHENG Ling-mei SUN Hong-xiang LOU 

机构地区：[1]School of Pharmaceutical Sciences, Shandong University Ji-nan 250012, China

出　　处：《Acta Pharmacologica Sinica》2008年第12期1478-1485,共8页中国药理学报（英文版）

基　　金：This work was supported by the National Basic Research Program （973 Program） of China （No 2006CB708511） and the National Natural Science Foundation of China （No 30730109 and 30672531）.Acknowledgements We thank Shu-juan SUN of Shandong Provincial Qianfoshan Hospital of China for donating the yeast isolates, and Bo-qin LI and Lei WANG for excellent technical assistance.

摘　　要：Aim： To investigate the effect of plagiochin E （PLE）, an antifungal macrocyclic bis（bibenzyl） isolated from liverwort Marehantia polymorpha L, on cell wall chitin synthesis in Candida albicans. Methods： The effect of PLE on chitin synthesis in Candida albicans was investigated at the cellular and molecular levels. First, the ultrastructural changes were observed under transmission electron microscopy （TEM）. Second, the effects of PLE on chitin synthetase （Chs） activities in vitro were assayed using 6-O-dansyl-N-acetylglucosamine as a fluorescent substrate, and its effect on chitin synthesis in situ was assayed by spheroplast regeneration. Finally, real-time RT-PCR was performed to assay its effect on the expression of Chs genes （CHS）. Results： Observation under TEM showed that the structure of the cell wall in Candida albicans was seriously damaged, which suggested that the antifungal activity of PLE was associated with its effect on the cell wall. Enzymatic assays and spheroplast regeneration showed that PLE inhibited chitin synthesis in vitro and in situ. The results of the PCR showed that PLE significantly downregulated the expression of CHS1, and upregulated the expression of CHS2 and CHS3. Because different Chs is regulated at different stages of transcription and post-translation, the downregulation of CHS1 would decrease the level of Chsl and inhibit its activity, and the inhibitory effects of PLE on Chs2 and Chs3 would be at the post-translational level or by the inhibition on the enzyme-active center. Conclusion： These results indicate that the antifungal activity of PLE would be attributed to its inhibitory effect on cell wall chitin synthesis in Candida albicans.Aim： To investigate the effect of plagiochin E （PLE）, an antifungal macrocyclic bis（bibenzyl） isolated from liverwort Marehantia polymorpha L, on cell wall chitin synthesis in Candida albicans. Methods： The effect of PLE on chitin synthesis in Candida albicans was investigated at the cellular and molecular levels. First, the ultrastructural changes were observed under transmission electron microscopy （TEM）. Second, the effects of PLE on chitin synthetase （Chs） activities in vitro were assayed using 6-O-dansyl-N-acetylglucosamine as a fluorescent substrate, and its effect on chitin synthesis in situ was assayed by spheroplast regeneration. Finally, real-time RT-PCR was performed to assay its effect on the expression of Chs genes （CHS）. Results： Observation under TEM showed that the structure of the cell wall in Candida albicans was seriously damaged, which suggested that the antifungal activity of PLE was associated with its effect on the cell wall. Enzymatic assays and spheroplast regeneration showed that PLE inhibited chitin synthesis in vitro and in situ. The results of the PCR showed that PLE significantly downregulated the expression of CHS1, and upregulated the expression of CHS2 and CHS3. Because different Chs is regulated at different stages of transcription and post-translation, the downregulation of CHS1 would decrease the level of Chsl and inhibit its activity, and the inhibitory effects of PLE on Chs2 and Chs3 would be at the post-translational level or by the inhibition on the enzyme-active center. Conclusion： These results indicate that the antifungal activity of PLE would be attributed to its inhibitory effect on cell wall chitin synthesis in Candida albicans.

关 键 词：plagiochin E macrocyclic bis（bibenzyl） Candida albicans cell wall chitin synthesis 

分 类 号：R96[医药卫生—药理学]