Liu Chang C, Schultz Peter G
Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Nat Biotechnol. 2006 Nov;24(11):1436-40. doi: 10.1038/nbt1254. Epub 2006 Oct 29.
Although tyrosine sulfation is a post-translational modification widespread across multicellular eukaryotes, its biological functions remain largely unknown. This is in part due to the difficulties of synthesizing selectively sulfated proteins. Here we report the selective incorporation of sulfotyrosine into proteins in bacteria by genetically encoding the modified amino acid in response to the amber nonsense codon TAG. Moreover, we show that this strategy enables direct expression in Escherichia coli of sulfo-hirudin, previously inaccessible through recombinant methods. The affinity of sulfo-hirudin toward human thrombin is enhanced more than tenfold over that of desulfo-hirudin, suggesting that sulfo-hirudin may offer clinical advantages for use as an anticoagulant. This general approach to the biosynthesis of sulfated proteins should facilitate further study and application of tyrosine sulfation.
尽管酪氨酸硫酸化是一种在多细胞真核生物中广泛存在的翻译后修饰，但其生物学功能在很大程度上仍不为人知。部分原因在于合成选择性硫酸化蛋白质存在困难。在此，我们报告了通过对琥珀色无义密码子TAG进行遗传编码修饰氨基酸，从而在细菌中实现将磺基酪氨酸选择性掺入蛋白质中。此外，我们表明该策略能够在大肠杆菌中直接表达磺基水蛭素，而这是之前通过重组方法无法实现的。磺基水蛭素对人凝血酶的亲和力比去磺基水蛭素增强了十多倍，这表明磺基水蛭素作为抗凝剂可能具有临床优势。这种硫酸化蛋白质生物合成的通用方法应有助于酪氨酸硫酸化的进一步研究和应用。
