has role D-proline L-proline CHEBI:6286 CHEBI:13154 CHEBI:45040 (S)-2-pyrrolidinecarboxylic acid PROLINE prolina (2S)-pyrrolidine-2-carboxylic acid PROLINE prolinum (S)-pyrrolidine-2-carboxylic acid L-Prolin CHEBI:21373 CHEBI:45100 L-(-)-proline L-Proline L-pyrrolidine-2-carboxylic acid CHEBI:184637 CHEBI:17203 chebi_ontology L-alpha-pyrrolidinecarboxylic acid (-)-(S)-proline (-)-2-pyrrolidinecarboxylic acid P Pyrrolidine in which the <em>pro</em>-<i>S</i> hydrogen at position 2 is substituted by a carboxylic acid group. <small>L</small>-Proline is the only one of the twenty DNA-encoded amino acids which has a secondary amino group α to the carboxyl group. It is an essential component of collagen and is important for proper functioning of joints and tendons. It also helps maintain and strengthen heart muscles. 2-Pyrrolidinecarboxylic acid L-Proline CHEBI:42067 (-)-proline (S)-2-carboxypyrrolidine CHEBI:45159 compatible osmolytes glutamine family amino acid proline micronutrient L-prolinate L-prolinium nutraceutical L-proline zwitterion mouse metabolite Saccharomyces cerevisiae metabolite Escherichia coli metabolite algal metabolite