微量滴度酶标板法测定棉蚜(Aphis gossypii Glover)酯酶特性与有机磷抗性的关系

通过生物测定表明高密棉蚜对有机磷的抗性高于北京棉蚜,用紫外分光光度计比色法(A法)及微量滴度酶标板法(B法 )测定高密棉蚜及北京棉蚜的α-乙酸萘酯酯酶活力和α-乙酸萘酯酯酶动力学。北京棉蚜和高密棉蚜的α- NA酯酶活力分别为 2.23、4.48(A法 )和1.13、3.30(B法)μmol·mg-1pro.·min-1,高密、北京棉蚜的酶活之比为 2 .00(A法 )、2 .92(B法) ;北京棉蚜、高密棉蚜的Km值分别为:6.06×10-5、7.51× 10-5(A法 )和 7.66×10-5、8.87×10-5 (B法) mol·L-1,Vmax值为2.53、5.82(A法)和1.28、3.61(B法)μmol·mg-1·min-1。比较紫外分光光度计比色法及微量滴度酶标板法的测定结果,表明微量滴度酶标板法的测定结果是可靠的。

A 96-Well Microplate Reader for Measuring Characterization of Esterase and Insecticide Resistance in the Cotton Aphids (Aphis gossypii Glover)

The bioassay showed that Gaomi cotton aphid had higher resistance to organophosphate insecticides than Beijing cotton aphid. Using two approaches, a conventional spectrophotometer (method A) and a96-well microplate reader method (method B),to detect general α-naphthyl acetate(α-NA) esterase activity and kinetics of α--NA esterase of Gaomi and Beijing cotton aphid. The α-NA esterase activity of Beijing and Gaomi cotton aphid were 2.23 and 4.48 (method A),1.28 and 3.30 μmol·mg-1 protein·min-1 (method B),respectively; The α-NA esterase activity ratio of G/B were 2.00 and 2.56; Km of α-NA esterase in Beijing and Gaomi cotton aphid were 6.06×10-5 and 7.51×10-5 (method A),7.66×10-5 and 8.87×10-5 (method B) mol·L-1 , respectively; Vmax were 2.53 and 5.82 (method A),1.28 and 3.61(method B) μmol·mg-1 protein·min-1 , respectively. Data obtained from the 96-well microplate reader were compared to those obtained, under similar conditions, in a conventional spectrophotometer. The approach of using the 96-well microplate reader should be generally applicable to monitor pest resistance to insecticide.