pyruvate decarboxylase activity 2-oxo-acid carboxy-lyase (aldehyde-forming) 2-oxo-acid carboxy-lyase activity Catalysis of the reaction: a 2-oxo acid = an aldehyde + CO2. EC:4.1.1.1 GO:0004737 MetaCyc:PYRUVATE-DECARBOXYLASE-RXN RHEA:11631 alpha-carboxylase activity alpha-ketoacid carboxylase activity molecular_function pyruvic decarboxylase activity