Wei Y, Contreras J A, Sheffield P, Osterlund T, Derewenda U, Kneusel R E, Matern U, Holm C, Derewenda Z S
Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville 22906-0011, USA.
Nat Struct Biol. 1999 Apr;6(4):340-5. doi: 10.1038/7576.
Brefeldin A esterase (BFAE), a detoxifying enzyme isolated from Bacillus subtilis, hydrolyzes and inactivates BFA, a potent fungal inhibitor of intracellular vesicle-dependent secretory transport and poliovirus RNA replication. We have solved the crystal structure of BFAE and we discovered that the previously reported amino acid sequence was in serious error due to frame shifts in the cDNA sequence. The correct sequence, inferred from the experimentally phased electron density map, revealed that BFAE is a homolog of the mammalian hormone sensitive lipase (HSL). It is a canonical alpha/beta hydrolase with two insertions forming the substrate binding pocket. The enzyme contains a lipase-like catalytic triad, Ser 202, Asp 308 and His 338, consistent with mutational studies that implicate the homologous Ser 424, Asp 693 and His 723 in the catalytic triad in human HSL.
布雷菲德菌素A酯酶（BFAE）是一种从枯草芽孢杆菌中分离出的解毒酶，可水解并使布雷菲德菌素A（BFA）失活，BFA是一种强效的真菌抑制剂，可抑制细胞内依赖囊泡的分泌运输和脊髓灰质炎病毒RNA复制。我们解析了BFAE的晶体结构，发现先前报道的氨基酸序列因cDNA序列的移码而存在严重错误。从实验定相的电子密度图推断出的正确序列显示，BFAE是哺乳动物激素敏感脂肪酶（HSL）的同源物。它是一种典型的α/β水解酶，有两个插入片段形成底物结合口袋。该酶含有一个类似脂肪酶的催化三联体，即Ser 202、Asp 308和His 338，这与突变研究结果一致，该研究表明人HSL催化三联体中的同源Ser 424、Asp 693和His 723参与催化作用。
