Thim L, Moody A J
Peptides. 1981;2 Suppl 2:37-9. doi: 10.1016/0196-9781(81)90007-3.
Glicentin or gut GLI-1 has previously been isolated from porcine small intestine. On the basis of the available chemical data, the molecule was thought to contain 100 amino acid residues. A redetermination of the amino acid composition of the molecule has shown it to contain 69 amino acid residues, and the full sequence has been established. The sequence of glicentin can be outlined as: GRPP1--30-Lys-Arg-Glucagon33--61-Lys-Arg-Hexapeptide64--69 where GRPP1--30 probably corresponds to the glicentin related pancreatic peptide previously isolated from porcine pancreas. In the pancreas, the two dibasic sequences (Lys31-Arg32 and Lys62-Arg63) probably represent sites of post-synthetic enzymatic cleavages by analogy with the two dibasic sequences of proinsulin. Glicentin thus fulfills the structural requirements for being all or a part of porcine proglucagon. In the intestine, glicentin could be the precursor of oxyntomodulin, a small molecular weight gut GLI presumably identical to glicentin 33--69, i.e., glucagon extended at the C-terminal end by an octapeptide.
胰高血糖素原或肠GLI-1先前已从猪小肠中分离出来。根据现有的化学数据，该分子被认为含有100个氨基酸残基。对该分子氨基酸组成的重新测定表明它含有69个氨基酸残基，并且其完整序列已被确定。胰高血糖素原的序列可概述为：GRPP1-30-赖氨酸-精氨酸-胰高血糖素33-61-赖氨酸-精氨酸-六肽64-69，其中GRPP1-30可能对应于先前从猪胰腺中分离出的与胰高血糖素原相关的胰肽。在胰腺中，这两个双碱性序列（赖氨酸31-精氨酸32和赖氨酸62-精氨酸63）可能类似于胰岛素原的两个双碱性序列，代表合成后酶切位点。因此，胰高血糖素原满足作为猪胰高血糖素原全部或部分的结构要求。在肠道中，胰高血糖素原可能是胃泌酸调节素的前体，胃泌酸调节素是一种小分子量的肠GLI，大概与胰高血糖素33-69相同，即胰高血糖素在C末端延伸一个八肽。
