Sogabe Satoshi, Masubuchi Miyako, Sakata Kiyoaki, Fukami Takaaki A, Morikami Kenji, Shiratori Yasuhiko, Ebiike Hirosato, Kawasaki Kenichi, Aoki Yuko, Shimma Nobuo, D'Arcy Allan, Winkler Fritz K, Banner David W, Ohtsuka Tatsuo
Nippon Roche Research Center, 200 Kajiwara, Kamakura, Kanagawa 247-8530, Japan.
Chem Biol. 2002 Oct;9(10):1119-28. doi: 10.1016/s1074-5521(02)00240-5.
Myristoyl-CoA:protein N-myristoyltransferase (Nmt) is a monomeric enzyme that catalyzes the transfer of the fatty acid myristate from myristoyl-CoA to the N-terminal glycine residue of a variety of eukaryotic and viral proteins. Genetic and biochemical studies have established that Nmt is an attractive target for antifungal drugs. We present here crystal structures of C. albicans Nmt complexed with two classes of inhibitor competitive for peptide substrates. One is a peptidic inhibitor designed from the peptide substrate; the other is a nonpeptidic inhibitor having a benzofuran core. Both inhibitors are bound into the same binding groove, generated by some structural rearrangements of the enzyme, with the peptidic inhibitor showing a substrate-like binding mode and the nonpeptidic inhibitor binding differently. Further, site-directed mutagenesis for C. albicans Nmt has been utilized in order to define explicitly which amino acids are critical for inhibitor binding. The results suggest that the enzyme has some degree of flexibility for substrate binding and provide valuable information for inhibitor design.
肉豆蔻酰辅酶A：蛋白质N-肉豆蔻酰转移酶（Nmt）是一种单体酶，可催化肉豆蔻酸从肉豆蔻酰辅酶A转移至多种真核和病毒蛋白的N端甘氨酸残基上。遗传和生化研究表明，Nmt是抗真菌药物的一个有吸引力的靶点。我们在此展示了白色念珠菌Nmt与两类竞争性结合肽底物的抑制剂形成的复合物的晶体结构。一种是基于肽底物设计的肽类抑制剂；另一种是具有苯并呋喃核心的非肽类抑制剂。两种抑制剂都结合到由酶的一些结构重排产生的同一结合凹槽中，肽类抑制剂呈现出类似底物的结合模式，而非肽类抑制剂的结合方式不同。此外，已利用白色念珠菌Nmt的定点诱变来明确确定哪些氨基酸对抑制剂结合至关重要。结果表明该酶在底物结合方面具有一定程度的灵活性，并为抑制剂设计提供了有价值的信息。
