UniProt
Homepage Link: https://www.uniprot.org/help/about
Description: The Universal Protein Resource (UniProt) serves as a high-quality, comprehensive, and freely accessible resource of protein sequences and functions. The UniProt knowledgebase includes both manually-curated and automatically-annotated data.
Example record: Homogentisate 1,2-dioxygenase (HGD, human) UniProtKB:Q93099 catalyzes the reaction "homogentisate + O2 = 4-maleylacetoacetate + H(+)" RHEA:15449. See "Catalytic activity" section of HGD's entry
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