Erb-Downward John R, Noverr Mairi C
Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI 48201, USA.
Infect Immun. 2007 Jul;75(7):3498-505. doi: 10.1128/IAI.00232-07. Epub 2007 Apr 30.
Candida albicans produces lipid metabolites that are functionally similar to host prostaglandins. These studies, using mass spectrometry, demonstrate that C. albicans produces authentic prostaglandin E(2) (PGE(2)) from arachidonic acid. Maximal PGE(2) production was achieved at 37 degrees C in stationary-phase culture supernatants and in cell-free lysates generated from stationary-phase cells. Interestingly, PGE(2) production is inhibited by both nonspecific cyclooxygenase and lipoxygenase inhibitors but not by inhibitors specific for the cyclooxygenase 2 isoenzyme. The C. albicans genome does not possess a cyclooxygenase homolog; however, several genes that may play a role in prostaglandin production from C. albicans were investigated. It was found that a C. albicans fatty acid desaturase homolog (Ole2) and a multicopper oxidase homolog (Fet3) play roles in prostaglandin production, with ole2/ole2 and fet3/fet3 mutant strains exhibiting reduced PGE(2) levels compared with parent strains. This work demonstrates that the synthesis of PGE(2) in C. albicans proceeds via novel pathways.
白色念珠菌产生的脂质代谢产物在功能上与宿主前列腺素相似。这些利用质谱分析的研究表明,白色念珠菌可从花生四烯酸产生真正的前列腺素E2(PGE2)。在37摄氏度的静止期培养上清液以及由静止期细胞产生的无细胞裂解物中,PGE2的产量达到最大值。有趣的是,非特异性环氧化酶和脂氧合酶抑制剂均可抑制PGE2的产生,但对环氧化酶2同工酶特异性抑制剂无抑制作用。白色念珠菌基因组中不存在环氧化酶同源物;然而,对几个可能在白色念珠菌前列腺素产生中发挥作用的基因进行了研究。结果发现,白色念珠菌脂肪酸去饱和酶同源物(Ole2)和多铜氧化酶同源物(Fet3)在前列腺素产生中发挥作用,与亲本菌株相比,ole2/ole2和fet3/fet3突变株的PGE2水平降低。这项工作表明,白色念珠菌中PGE2的合成通过新的途径进行。