Soyez D, Toullec J Y, Ollivaux C, Géraud G
Laboratoire Signaux Endocrines et Toxines d'Invertébrés, CNRS EP2028-Univ. Paris 6, France.
J Biol Chem. 2000 Dec 1;275(48):37870-5. doi: 10.1074/jbc.M007302200.
Modification of the chirality of a single amino acid residue within a peptide chain appears to be novel additional mechanism leading to structural and functional diversification of eukaryotic bioactive peptides. This phenomenon has been studied at the cellular level in a neuroendocrine organ which elaborates a mixture of diastereoisomers of a 72-residue neuropeptide, crustacean hyperglycemic hormone. For the first time, amino acid isomerization has been shown to occur in the perikarya of fully specialized neurosecretory cells, as a late step of the maturation of the hyperglycemic hormone precursor and after propeptide cleavage. The specificity and efficiency of this phenomenon indicates the existence of a new enzyme family involved in the biogenesis of peptide hormones.
肽链内单个氨基酸残基手性的改变似乎是导致真核生物活性肽结构和功能多样化的一种新的额外机制。这种现象已在一个神经内分泌器官的细胞水平上进行了研究，该器官能产生一种由72个残基组成的神经肽——甲壳类高血糖激素的非对映异构体混合物。首次表明，氨基酸异构化发生在完全特化的神经分泌细胞的胞体中，是高血糖激素前体成熟的后期步骤，且发生在原肽裂解之后。这种现象的特异性和效率表明存在一个参与肽类激素生物合成的新酶家族。
