Endo F, Matsuda I
Department of Pediatrics, Kumamoto University Medical School, Japan.
Mol Biol Med. 1991 Feb;8(1):117-27.
Human prolidase (PEPD, iminodipeptidase, EC 3.4.13.9) and related deficiencies were analyzed in terms of the nature and molecular biology of the enzyme and the molecular events seen in patients with this deficiency. The analyses were based on findings concerning isolation of the enzyme, development of specific antibodies and molecular cloning of cDNA and genome DNA of human prolidase. The studies revealed that human prolidase is a homo-dimer of an identical subunit 492 amino acid residues. The gene for prolidase (PEPD gene) was localized on chromosome 19, spanned more than 130 x 10(3) base-pairs and split into 15 exons. Molecular defects in prolidase deficiency were then analyzed. Two patients with the polypeptide-positive phenotype of the disease carried a mis-sense mutation of exon 12. Two siblings with a polypeptide-negative phenotype carried a gene deletion that encompassed exon 14. These mutations were not found in ten other patients with the disease, hence the molecular defects in prolidase deficiency are apparently highly heterogeneous.
从该酶的性质和分子生物学以及该酶缺乏症患者中观察到的分子事件方面，对人氨肽酶（PEPD，亚氨基二肽酶，EC 3.4.13.9）及相关缺乏症进行了分析。这些分析基于有关该酶分离、特异性抗体的研发以及人氨肽酶cDNA和基因组DNA分子克隆的研究结果。研究表明，人氨肽酶是由492个氨基酸残基的相同亚基组成的同型二聚体。氨肽酶基因（PEPD基因）定位于19号染色体，跨度超过130×10³碱基对，分为15个外显子。随后对氨肽酶缺乏症的分子缺陷进行了分析。两名具有该疾病多肽阳性表型的患者携带第12外显子的错义突变。两名具有多肽阴性表型的同胞携带包含第14外显子的基因缺失。在其他十名患有该疾病的患者中未发现这些突变，因此氨肽酶缺乏症的分子缺陷显然具有高度异质性。
