期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1987
卷号：84
期号：2
页码：368-372
DOI：10.1073/pnas.84.2.368
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Vitamin K-dependent protein S is involved in the regulation of blood coagulation. It is a 75-kDa single chain protein with an NH2-terminal gamma-carboxyglutamic acid-containing domain followed by a thrombin-sensitive region and four domains arranged in tandem, each of which is homologous to the epidermal growth factor (EGF) precursor. The NH2-terminal EGF-like domain contains beta-hydroxyaspartic acid, which has been identified in vitamin K-dependent proteins. The following EGF-like repeat has a very pronounced sequence homology (10 consecutive residues identical) to one of the EGF-like units in the EGF precursor. We now show that, in protein S, this EGF-like repeat has one beta-hydroxyasparagine residue formed by hydroxylation of asparagine. The two COOH-terminal EGF-like repeats also contain beta-hydroxyasparagine, an amino acid not previously found in proteins. Sequence comparisons have enabled us to identify a consensus sequence that seems to be required by the hydroxylase(s).
