Pesliakas H, Zutautas V, Baskeviciute B
Department of Research, Institute of Biotechnology Fermentas, Vilnius, Lithuania.
J Chromatogr A. 1994 Aug 26;678(1):25-34. doi: 10.1016/0021-9673(94)87070-5.
Affinity partitioning of yeast alcohol dehydrogenase (YADH), lactate dehydrogenase from rabbit muscle (MLDH) and lactate and malate dehydrogenases from pig heart (HLDH and HMDH, respectively) were studied in aqueous two-phase systems containing metal ions (Cu2+, Ni2+, Zn2+ and Cd2+) chelated by iminodiacetate-poly(ethylene glycol) (IDA-PEG). The partitioning behaviour of the enzymes in the presence of Cu(II)-IDA-PEG was studied as a function of the concentration of NaCl, the pH of the medium and the concentration of added selected agents. It was demonstrated that the partition effect (delta log K) of dehydrogenases in the presence of Cu(II)-IDA-PEG and the affinity of enzymes for immobilized Cu2+ ions increases in the order MLDH > YADH > HMDH > or = HLDH. It was shown that the determined variations in the enzyme affinities for Cu(II)-IDA-PEG might be related to the differences in the content of histidine residues accessible to the solvent.
在含有亚氨基二乙酸 - 聚乙二醇(IDA - PEG)螯合的金属离子(Cu2 +、Ni2 +、Zn2 +和Cd2 +)的双水相体系中,研究了酵母乙醇脱氢酶(YADH)、兔肌肉乳酸脱氢酶(MLDH)以及猪心脏乳酸脱氢酶和苹果酸脱氢酶(分别为HLDH和HMDH)的亲和分配。研究了在Cu(II) - IDA - PEG存在下,酶的分配行为随NaCl浓度、介质pH值和所选添加剂浓度的变化。结果表明,在Cu(II) - IDA - PEG存在下,脱氢酶的分配效应(δlogK)以及酶对固定化Cu2 +离子的亲和力按MLDH > YADH > HMDH >或= HLDH的顺序增加。结果表明,所测定的酶对Cu(II) - IDA - PEG亲和力的变化可能与溶剂可及的组氨酸残基含量的差异有关。