Pyrrole-2-carboxylic acid is an organic compound with the formula HNC<sub>4</sub>H<sub>3</sub>CO<sub>2</sub>H. It is one of two monocarboxylic acids of pyrrole. It is a white solid. It arises in nature by dehydrogenation of the amino acid proline. It also arises by carboxylation of pyrrole. The ethyl ester of this acid is readily prepared from pyrrole.
In bacteria including Arthrobacter and Rhodococcus species, a specific enzyme, pyrrole-2-carboxylate monooxygenase converts pyrrole-2-carboxylic acid to its 5-hydroxypyrrole derivative.
The enzyme uses nicotinamide adenine dinucleotide as a cofactor.