中文摘要：

细胞色素P450单加氧化酶系在生物体对外源化合物的代谢和内源化合物的调节都起着非常重要的作用，许多证据表明昆虫杀虫剂抗性的产生与单加氧化酶系介导的代谢反应有关，其关键组份细胞色素P450作为终端氧化酶能氧化多样的底物。依据家蚕基因组P450预测序列设计1对引物，以家蚕中肠为材料提取mRNA，采用RT-PCR方法克隆了P450家族基因CYP6B29（GenBank登录号：DQ252324）。序列分析表明，该基因的ORF为1518bp，编码505个氨基酸，预测其相对分子质量约为58kD，等电点为8．29。经与已知P450的6B亚族其它所有成员氨基酸同源比对发现，CYP6B29基因与美洲棉铃虫CYP6B27基因的同源关系最近，同源性达到60．5％。

英文摘要：

The cytochrome P450-dependent monooxygenases play an extremely important role in metabolic system involved in the catabolism and anabolism of xenobiotics and endogenous compounds. Insecticide resistance has been proven to be correlated with monooxygenase-mediated metabolism. Cytochrome P450 is a hemoprotein which acts as the terminal oxidase in monooxygenase systems to oxidize diverse substrates. According to the predicted P450 sequences from the genome of Bombyx mori, a pair of primers were designed and a novel gene named CYP6B29 of cytochrome P450 was successfully cloned from the midgut mRNA of Bombyx mori by RT-PCR （GenBank accession number. DQ252324）. Sequence analysis results showed that CYF6B29 contains a 1 518 bp open reading frame, which encodes 505 amino acid residues （m. w. 58 kD, pl 8.29）. The comparison of CYP6B29 amino acid sequence with those of nearly all the other known members of P450 6B subfamily showed that CYP6B29 shared the highest identity （60.5%） with CYP6B27 from Helicoverpa zea.