Lodge J K, Jackson-Machelski E, Toffaletti D L, Perfect J R, Gordon J I
Department of Molecular Biology and Pharmacology, Washington University School of Medicine, St. Louis, MO 63110.
Proc Natl Acad Sci U S A. 1994 Dec 6;91(25):12008-12. doi: 10.1073/pnas.91.25.12008.
Cryptococcus neoformans is a major cause of systemic fungal infection in immunocompromised patients. Myristoyl-CoA:protein N-myristoyltransferase (Nmt) catalyzes the transfer of myristate (C14:0) from myristoyl-CoA to the N-terminal glycine of a subset of cellular proteins produced during vegetative growth of C. neoformans. A Gly487-->Asp mutation was introduced into C. neoformans NMT by targeted gene replacement. The resulting strains are temperature-sensitive myristic acid auxotrophs. They are killed at 37 degrees C when placed in medium lacking myristate and, in an immunosuppressed animal model of cryptococcal meningitis, are completely eliminated from the subarachnoid space within 12 days of initial infection. C. neoformans and human Nmts exhibit differences in their peptide substrate specificities. These differences can be exploited to develop a new class of fungicidal drugs.
新型隐球菌是免疫功能低下患者系统性真菌感染的主要病因。肉豆蔻酰辅酶A：蛋白质N-肉豆蔻酰转移酶（Nmt）催化在新型隐球菌营养生长期间产生的一部分细胞蛋白质的N-末端甘氨酸上肉豆蔻酸（C14:0）从肉豆蔻酰辅酶A的转移。通过靶向基因置换将Gly487→Asp突变引入新型隐球菌NMT。所得菌株是温度敏感型肉豆蔻酸营养缺陷型。当置于缺乏肉豆蔻酸的培养基中时，它们在37℃下被杀死，并且在隐球菌性脑膜炎的免疫抑制动物模型中，在初次感染后12天内从蛛网膜下腔中完全清除。新型隐球菌和人类Nmt在其肽底物特异性方面存在差异。这些差异可被用于开发一类新型的杀真菌药物。
