DNA-directed assembly of artificial multienzyme complexes

This study aims to establish model systems for the exploration of proximity effects, occurring in natural multienzyme complexes. DNA-directed assembly of covalent conjugates of DNA oligonucleotides and Glucose Oxidase (GOX) or Horseradish peroxidase (HRP) was used to generate supramolecular complexes, in which the two enzymes were arranged with defined spatial orientation. Electrophoretic studies indicated that the assembly efficiency significantly depends on positional and sterical factors of the two DNA–enzyme conjugates. Kinetic rate measurements of the coupled reaction of glucose oxidation and Amplex Red peroxidation were carried out with microplate-immobilized DNA–GOX–HRP complexes, and the influence of Catalase on this reaction was determined. The kinetic measurements revealed a significant increase in the reactivity of the complexes, in which GOX and HRP were immobilized in direct proximity on a complementary DNA carrier.