Amaya María Fernanda, Watts Andrew G, Damager Iben, Wehenkel Annemarie, Nguyen Tong, Buschiazzo Alejandro, Paris Gastón, Frasch A Carlos, Withers Stephen G, Alzari Pedro M
Unité de Biochimie Structurale, CNRS URA 2185, Institut Pasteur, 25 rue du Dr. Roux, 75724 Paris, France.
Structure. 2004 May;12(5):775-84. doi: 10.1016/j.str.2004.02.036.
Sialidases are a superfamily of sialic-acid-releasing enzymes that are of significant interest due to their implication as virulence factors in the pathogenesis of a number of diseases. However, extensive studies of viral and microbial sialidases have failed to provide a comprehensive picture of their mechanistic properties, in part because the structures of competent enzyme-substrate complexes and reaction intermediates have never been described. Here we report these structures for the Trypanosoma cruzi trans-sialidase (TcTS), showing that catalysis by sialidases occurs via a similar mechanism to that of other retaining glycosidases, but with some intriguing differences that may have evolved in response to the substrate structure.
唾液酸酶是一类释放唾液酸的酶的超家族，由于它们在多种疾病的发病机制中作为毒力因子而备受关注。然而，对病毒和微生物唾液酸酶的广泛研究未能全面揭示其机制特性，部分原因是尚未描述过有活性的酶-底物复合物和反应中间体的结构。在此，我们报告了克氏锥虫转唾液酸酶（TcTS）的这些结构，表明唾液酸酶的催化作用通过与其他保留型糖苷酶类似的机制发生，但存在一些有趣的差异，这些差异可能是为响应底物结构而进化形成的。
