Substrate specificity of polyphenol oxidase
Mark-Anthony McLarin, Ivanhoe KH Leung
CRITICAL REVIEWS IN BIOCHEMISTRY AND MOLECULAR BIOLOGY | TAYLOR & FRANCIS LTD | Published : 2020
The ubiquitous type-3 copper enzyme polyphenol oxidase (PPO) has found itself the subject of profound inhibitor research due to its role in fruit and vegetable browning and mammalian pigmentation. The enzyme itself has also been applied in the fields of bioremediation, biocatalysis and biosensing. However, the nature of PPO substrate specificity has remained elusive despite years of study. Numerous theories have been proposed to account for the difference in tyrosinase and catechol oxidase activity. The "blocker residue" theory suggests that bulky residues near the active site cover CuA, preventing monophenol coordination. The "second shell" theory suggests that residues distant (∼8 Å) from ..View full abstract
We thank the University of Auckland for funding.