vander Straten A, Herzog A, Jacobs P, Cabezón T, Bollen A
EMBO J. 1983;2(6):1003-7. doi: 10.1002/j.1460-2075.1983.tb01534.x.
Human haptoglobin (Hp) is a plasma glycoprotein composed of alpha and beta polypeptide chains that are covalently associated by disulfide bonds. It had been suggested that alpha and beta polypeptides could be synthesized via a common precursor polypeptide. We report the molecular cloning of DNA complementary to human Hp mRNA. One of the clones, pULB1148, carries a full length copy coding for both alpha 2 and beta polypeptides. In vitro translation of human liver mRNA hybridizing with this cDNA gives a protein mol. wt. of 49000 daltons. The sequence of the alpha 2 beta cDNA shows the presence of a single Arg residue between Gln 142 of the alpha 2 chain and Ileu 1 of the beta chain. With a few minor exceptions, the DNA sequence fits the previously published amino acid sequences. The differences are the presence of an Asp residue at position 52 of alpha 2 instead of Asn, the existence in beta of only one Lys residue between Gly 65 and the following Gln, the presence of Ser and Cys at positions 218-219 instead of Cys-Ser, and of Asp residues at positions 205 and 235 instead of Asn.
人触珠蛋白（Hp）是一种血浆糖蛋白，由通过二硫键共价结合的α和β多肽链组成。有人提出α和β多肽可以通过共同的前体多肽合成。我们报道了与人Hp mRNA互补的DNA的分子克隆。其中一个克隆pULB1148携带编码α2和β多肽的全长拷贝。与此cDNA杂交的人肝mRNA的体外翻译产生一种分子量为49000道尔顿的蛋白质。α2β cDNA的序列显示在α2链的Gln 142和β链的Ileu 1之间存在单个Arg残基。除了一些小的例外，DNA序列与先前发表的氨基酸序列相符。差异在于α2的第52位存在Asp残基而非Asn，β在Gly 65和随后的Gln之间仅存在一个Lys残基，在第218 - 219位存在Ser和Cys而非Cys - Ser，以及在第205和235位存在Asp残基而非Asn。
