Substrate specificity of polyphenol oxidase

@article{McLarin2020SubstrateSO,
  title={Substrate specificity of polyphenol oxidase},
  author={Mark-Anthony McLarin and Ivanhoe K. H. Leung},
  journal={Critical Reviews in Biochemistry and Molecular Biology},
  year={2020},
  volume={55},
  pages={274 - 308}
}
Abstract 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… 
Considerations on activity determinants of fungal polyphenol oxidases based on mutational and structural studies
TLDR
The findings improve current understanding of structure-function relations of microbial PPOs, which is a prerequisite for the engineering of biocatalysts of desired properties.
Considerations Regarding Activity Determinants of Fungal Polyphenol Oxidases Based on Mutational and Structural Studies
TLDR
The crystal structure of a TtPPO variant, determined at 1.55 Å resolution, represents the second known structure of an ascomycete PPO and improves current understanding of structure-function relations of microbial PPOs, which is a prerequisite for the engineering of biocatalysts of desired properties.
The basicity of an active-site water molecule discriminates between tyrosinase and catechol oxidase activity.
TLDR
The ability of the substrates to dissociate the motif shielding the active-site pocket seems to contribute critically to the substrate specificity of Ty and the deprotonation of the substrate hydroxyl by the bridging hydroxide seems to be significant for the efficient catalytic cycle of the phenolase reaction.
Toward more specific inhibitor for Solanum tuberosum polyphenol oxidase through a structural insight into its activities and inhibition.
TLDR
Light is shed on the physicochemical properties of PPOsol that can be used in making various formulations for safe controlling enzymatic browning of potatoes, especially fresh-cut and minimally processed products, and similar crops products during postharvest and the processes of products preparations.
Polyphenol-Hydroxylating Tyrosinase Activity under Acidic pH Enables Efficient Synthesis of Plant Catechols and Gallols
TLDR
The results suggest that microbial tyrosinase is a useful biocatalyst to prepare plant polyphenolic catechols and gallols with high productivity, which were hardly achieved by using other monooxygenases such as cytochrome P450s.
Differential specificities of polyphenol oxidase from lotus seeds (Nelumbo nucifera Gaertn.) toward stereoisomers, (−)-epicatechin and (+)-catechin: Insights from comparative molecular docking studies
Abstract Lotus seeds are highly susceptible to browning because of the catalysis of polyphenol oxidase (PPO), which caused a tremendous waste of lotus resources, so it is urgent to investigate the
Spectrophotometric Assays for Sensing Tyrosinase Activity and Their Applications
TLDR
The information and knowledge presented in this review offer a group of practical and reliable assays and imaging tools for sensing TYR activities in complex biological systems, which strongly facilitates high-throughput screening TYR inhibitors and further investigations on the relevance of TYR to human diseases.
Thermal inactivation kinetics of peroxidase and polyphenol oxidase from pomegranate arils (Punica granatum L. cv. Wonderful).
TLDR
Thermal inactivation of peroxidase (POD) and polyphenol oxidase (PPO) in both pomegranate arils crude enzyme extract and fresh juice was investigated to offer a better insight of characterization of browning enzymes and their thermosatbility, which will be useful to control the possible browning of pome granite arils during processing and storage.
Characterization and optimisation of a novel laccase from Sulfitobacter indolifex for the decolourisation of organic dyes.
  • Nabangshu Sharma, I. Leung
  • Medicine
    International journal of biological macromolecules
  • 2021
TLDR
The use of enzyme immobilisation technology to improve the operational stability and reusability of the putative laccase was investigated and it was found that immobilising the enzyme through the cross-linked enzyme aggregates (CLEA) method significantly improved its tolerance towards extreme pH as well as the presence of organic solvents.
Novel Thermophilic Bacterial Laccase for the Degradation of Aromatic Organic Pollutants
  • Nabangshu Sharma, I. Leung
  • Medicine
    Frontiers in Chemistry
  • 2021
TLDR
The putative laccase exhibits broad pH and temperature stability, and, notably, it could catalyse the degradation of organic dyes as well as toxic pollutants including bisphenol A, guaiacol and phenol with a redox mediator.
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