Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 143-901, Korea.
Biotechnol Lett. 2010 Apr;32(4):579-84. doi: 10.1007/s10529-009-0188-x. Epub 2009 Dec 24.
Biosynthesis of flavonoid derivatives requires enzyme(s) having high reactivity as well as regioselectivity. We have synthesized 3-O-kaempferol from naringenin using two enzymes. The first reaction, in which naringenin is converted to kaempferol, is mediated by flavonol synthase (FLS). An FLS (PFLS) with strong catalytic activity was cloned and characterized from the genome sequence of the poplar (Populus deltoides). PFLS consists of a 1,008 bp ORF encoding a 38 kDa protein. PFLS was expressed in Escherichia coli with a glutathione-S-transferase (GST) tagging. The purified recombinant PFLS was characterized. Catalytically, it was more efficient than the previously characterized FLSs. A mixture of two E. coli transformants harboring either PFLS or ROMT9 (a kaempferol 3-O-methyltransferase) converted naringenin into 3-O-methylkaempferol.
类黄酮衍生物的生物合成需要具有高反应性和区域选择性的酶。我们使用两种酶从柚皮素合成了 3-O-山柰酚。第一个反应是由黄酮醇合酶（FLS）介导的，将柚皮素转化为山柰酚。我们从杨树（Populus deltoides）的基因组序列中克隆并鉴定了一种具有强催化活性的 FLS（PFLS）。PFLS 由一个编码 38 kDa 蛋白的 1008 bp ORF 组成。PFLS 在大肠杆菌中表达，带有谷胱甘肽-S-转移酶（GST）标签。纯化的重组 PFLS 进行了表征。在催化方面，它比以前鉴定的 FLS 更有效。含有 PFLS 或 ROMT9（山柰酚 3-O-甲基转移酶）的两种大肠杆菌转化体的混合物将柚皮素转化为 3-O-甲基山柰酚。
