Scott J G, Lee S S
Department of Entomology, Cornell University, Ithaca, New York 14853-0999.
Arch Insect Biochem Physiol. 1993;24(1):1-19. doi: 10.1002/arch.940240102.
A cytochrome P-450 (P-450) was purified from abdominal microsomes of untreated and phenobarbital treated susceptible (S+) and insecticide-resistant (LPR) houseflies using HPLC purification procedures. The purified P-450s exhibited the same apparent molecular masses (54,400 dalton) and could not be distinguished from each other on the basis of HPLC chromatographic properties, reduced CO-difference absorbance maxima (447 +/- 0.5 nm), or partial NH2-terminal sequences (MLLLLLLIVVTTLYIFAKL). Since these P-450s were indistinguishable and were immunologically identical to cytochrome P-450lpr we conclude that these P-450s are in fact cytochrome P-450lpr. The level of P-450lpr was increased twofold after PB exposure in the S+ strain, while the level of P-450lpr did not change in the LPR strain. Immunoinhibition of ECOD activity with anti-P-450lpr antiserum suggests that PB treatment in S+ house flies induced P-450lpr, and other forms of cytochromes P-450 with high activity toward this substrate.
利用高效液相色谱（HPLC）纯化程序，从未经处理和经苯巴比妥处理的敏感（S+）及抗杀虫剂（LPR）家蝇的腹部微粒体中纯化出一种细胞色素P-450（P-450）。纯化后的P-450表现出相同的表观分子量（54,400道尔顿），基于HPLC色谱特性、还原型一氧化碳差示吸光度最大值（447±0.5纳米）或部分氨基末端序列（MLLLLLLIVVTTLYIFAKL）无法相互区分。由于这些P-450难以区分且在免疫上与细胞色素P-450lpr相同，我们得出结论，这些P-450实际上就是细胞色素P-450lpr。在S+品系中，苯巴比妥暴露后P-450lpr的水平增加了两倍，而在LPR品系中P-450lpr的水平没有变化。用抗P-450lpr抗血清对乙氧甲叉胆色素脱甲基酶（ECOD）活性进行免疫抑制表明，S+家蝇经苯巴比妥处理后诱导了P-450lpr以及对该底物具有高活性的其他细胞色素P-450形式。
