Lapointe S, Légaré C, Gaudreault C, Sullivan R, Sirard M A
Centre de Recherche en Biologie de la Reproduction, Université Laval, Ste-Foy, Québec, Canada.
Mol Reprod Dev. 1998 Nov;51(3):265-73. doi: 10.1002/(SICI)1098-2795(199811)51:3<265::AID-MRD5>3.0.CO;2-N.
A bovine oviductal fluid catalase (OFC) which preferentially binds to the acrosome surface of some mammalian spermatozoa has recently been purified. The objectives of this study were to clone the OFC, obtain the full-length cDNA and protein sequence and determine which characteristics of the proteins are associated with the binding of the enzyme to sperm surface. Northern blot analysis revealed low levels of catalase mRNA in bovine oviducts and uterus compared to the liver and kidney. Screening of a cDNA library from the cow oviduct permit to obtain a full-length cDNA of 2282 bp, with an open reading frame of 1581 bp coding for a deduced protein of 526 amino acids (59,789 Da). The deduced protein contained four potential N-glycosylation sites and many potential O-glycosylation sites. The OFC protein exhibited high identity with catalase from other bovine tissues, likewise with catalases from human fibroblast and kidney, and with rat liver catalase. The homology of amino acid sequence of OFC with bovine liver catalase was about 99%. However the OFC possess an extended carboxyl terminus of 20 amino acids not present on the liver catalase. This result is supported by a lower mobility of the OFC compared to the liver catalase when both proteins are submitted on SDS-PAGE.
最近已纯化出一种优先结合某些哺乳动物精子顶体表面的牛输卵管液过氧化氢酶（OFC）。本研究的目的是克隆OFC，获得全长cDNA和蛋白质序列，并确定该蛋白质的哪些特征与酶与精子表面的结合有关。Northern印迹分析显示，与肝脏和肾脏相比，牛输卵管和子宫中过氧化氢酶mRNA水平较低。对牛输卵管cDNA文库的筛选获得了一个2282 bp的全长cDNA，其开放阅读框为1581 bp，编码一个推导的526个氨基酸（59,789 Da）的蛋白质。推导的蛋白质含有四个潜在的N-糖基化位点和许多潜在的O-糖基化位点。OFC蛋白与来自其他牛组织的过氧化氢酶高度同源，同样与人成纤维细胞和肾脏的过氧化氢酶以及大鼠肝脏过氧化氢酶高度同源。OFC与牛肝脏过氧化氢酶的氨基酸序列同源性约为99%。然而，OFC具有一个20个氨基酸的延伸羧基末端，而肝脏过氧化氢酶上不存在该末端。当两种蛋白质在SDS-PAGE上进行电泳时，OFC的迁移率低于肝脏过氧化氢酶，这一结果支持了上述结论。
