机构地区: 华南理工大学轻工与食品学院
出 处: 《食品与发酵工业》 2005年第9期21-23,共3页
摘 要: 采用5’和3’RACE技术和梯度PCR方法从盐藻中克隆了八氢番茄红素脱氢酶(Pds)全长cDNA,序列分析表明,该cDNA长2198bp,包含1个1752bp的开放阅读框(ORF),编码一段583氨基酸残基的多肽链。氨基酸序列的同源性分析表明,它与高等植物和蓝藻的八氢番茄红素脱氢酶序列一致性高达67%,而与细菌和酵母的序列同源性较差;在N端具有一段转运序列和辅助因子结合结构域,C端则有一胡萝卜素结合域。这些序列特征预示,盐藻Pds与其他绿藻、高等植物和蓝藻中的同源基因一样催化八氢番茄红素发生前2步脱氢反应,并且需要与另一个脱氢酶联合作用合成番茄红素。 A full-length cDNA encoding phytoene desatruase (Pds) was isolated from Dunaliella salina by 5', 3' RACE and gradient PCR. The cDNA, designated DsPds, is 2198 bp in length and has an open reading frame of 1752bp with a deduced amino acid sequences of 583 residues. The DsPds displays a rather high degree of identity (67 %) to Pds from other green algae, higher plants and a lower similarity with that from bacterium and yeast. The putative protein sequence of DsPds has a transit sequence and eofaetor binding-domain in N-terminal. There is a carotene binding-domain in C-terminal,which is also found in other green algae, higher plants and cyanobaeteria. This characteristics foreshow that, like these organisms,another desaturase is required to further finish the last two dehydryogenesis reactions leading to the synthesis of lycopene.