Bakke Mikio, Sato Tsuneo, Ichikawa Keiichi, Nishimura Ikuko
Research and Development Division, Kikkoman Corporation, 399 Noda, Noda City, Chiba 278-0037, Japan.
J Biotechnol. 2005 Sep 29;119(3):260-71. doi: 10.1016/j.jbiotec.2005.04.005.
The gene encoding histamine dehydrogenase in Rhizobium sp. 4--9 has been cloned and overexpressed in Escherichia coli. The coding region of the gene was 2,079 bp and encoded a protein of 693 amino acids with a calculated molecular mass of 76,732 Da. This histamine dehydrogenase was related to histamine dehydrogenase from Nocardioides simplex (54.5% identical), trimethylamine dehydrogenase from Methylophilus methylotrophus (39.3% identical) and dimethylamine dehydrogenase from Hyphomicrobium X (38.1% identical), which have a covalent 6-S-cysteinyl flavin mononucleotide and a [4Fe--4S] cluster as redox cofactors. Sequence alignment and a UV-visible absorption spectrum supported the presence of these cofactors in this histamine dehydrogenase. The investigation of the enzymatic properties suggested that this enzyme exhibited the most excellent substrate specificity toward histamine among all amine oxidases or dehydrogenases found to date. The recombinant enzyme was able to be used for the colorimetric determination of histamine, which gave a linear calibration curve and identical data with conventional methods.
根瘤菌属4-9中编码组胺脱氢酶的基因已被克隆并在大肠杆菌中过表达。该基因的编码区为2079 bp，编码一个由693个氨基酸组成的蛋白质，计算分子量为76732 Da。这种组胺脱氢酶与简单诺卡氏菌的组胺脱氢酶（同一性为54.5%）、嗜甲基甲基ophilus的三甲胺脱氢酶（同一性为39.3%）和X型生丝微菌的二甲胺脱氢酶（同一性为38.1%）相关，它们具有共价6-S-半胱氨酰黄素单核苷酸和一个[4Fe-4S]簇作为氧化还原辅因子。序列比对和紫外可见吸收光谱支持该组胺脱氢酶中存在这些辅因子。酶学性质研究表明，在迄今发现的所有胺氧化酶或脱氢酶中，该酶对组胺表现出最优异的底物特异性。该重组酶可用于组胺的比色测定，得到线性校准曲线且数据与传统方法一致。
