Enzyme Commission number

<p>The Enzyme Commission number (EC number) is a <a href="/facts/Numbering_scheme/upd3XfUo">numerical classification</a> scheme for <a href="/facts/Enzyme/DSI1Fh7y">enzymes</a>, based on the <a href="/facts/Chemical_reaction/GpqWlKrz">chemical reactions</a> they <a href="/facts/Catalysis/LPBS7TQC">catalyze</a>. As a system of enzyme nomenclature, every EC number is associated with a recommended name for the corresponding enzyme-catalyzed reaction.
</p><p>EC numbers do not specify enzymes but enzyme-catalyzed reactions. If different enzymes (for instance from different organisms) catalyze the same reaction, then they receive the same EC number. Furthermore, through <a href="/facts/Convergent_evolution/dd0L8z4R">convergent evolution</a>, completely different <a href="/facts/Protein_fold_class/s2vDRu46">protein folds</a> can catalyze an identical reaction (these are sometimes called <a href="/facts/Non-homologous_isofunctional_enzymes/Qv1HHYHk">non-homologous isofunctional enzymes</a>)  and therefore would be assigned the same EC number. By contrast, <a href="/facts/UniProt/lfDDHjAl">UniProt</a> identifiers uniquely specify a protein by its amino acid sequence.
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Enzyme Commission number open-in-new

Enzyme Commission number