Nishimura Motohiro, Kohno Kunie, Nishimura Yoshio, Inagaki Masanori, Davies Julian
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Yasuda Women's University.
Biosci Biotechnol Biochem. 2011;75(9):1770-7. doi: 10.1271/bbb.110301. Epub 2011 Sep 7.
We purified two isozymes of coniferyl alcohol dehydrogenase (CADH I and II) to homogeneity from cell-free extracts of Streptomyces sp. NL15-2K. The apparent molecular masses of CADH I and II were determined to be 143 kDa and 151 kDa respectively by gel filtration, whereas their subunit molecular masses were determined to be 35,782.2 Da and 37,597.7 Da respectively by matrix-assisted laser-desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Thus, it is probable that both isozymes are tetramers. The optimum pH and temperature for coniferyl alcohol dehydrogenase activity were pH 9.5 and 45 °C for CADH I and pH 8.5 and 40 °C for CADH II. CADH I oxidized various aromatic alcohols and allyl alcohol, and was most efficient on cinnamyl alcohol, whereas CADH II exhibited high substrate specificity for coniferyl alcohol, and showed no activity as to the other alcohols, except for cinnamyl alcohol and 3-(4-hydroxy-3-methoxyphenyl)-1-propanol. In the presence of NADH, CADH I and II reduced cinnamaldehyde and coniferyl aldehyde respectively to the corresponding alcohols.
我们从链霉菌属NL15 - 2K的无细胞提取物中纯化出两种松柏醇脱氢酶同工酶（CADH I和II），使其达到均一状态。通过凝胶过滤法测定，CADH I和II的表观分子量分别为143 kDa和151 kDa，而通过基质辅助激光解吸电离飞行时间质谱（MALDI - TOF - MS）测定，它们的亚基分子量分别为35,782.2 Da和37,597.7 Da。因此，这两种同工酶可能均为四聚体。CADH I的松柏醇脱氢酶活性的最适pH和温度分别为pH 9.5和45 °C，CADH II的则为pH 8.5和40 °C。CADH I可氧化多种芳香醇和烯丙醇，对肉桂醇的催化效率最高，而CADH II对松柏醇表现出高底物特异性，除肉桂醇和3 - (4 - 羟基 - 3 - 甲氧基苯基)-1 - 丙醇外，对其他醇类均无活性。在NADH存在的情况下，CADH I和II分别将肉桂醛和松柏醛还原为相应的醇。
