The two functional groups that together define an imino acid
Imino acids are structurally related to
amino acids, which have
amino group instead of imine—a difference of single vs double-bond between nitrogen and carbon. The simplest example is
dehydroglycine.
D-Amino acid oxidase is an
enzyme that is able to convert amino acids into imino acids. Also the direct
biosynthetic precursor to the amino acid
proline is the imino acid (S)-Δ1-pyrroline-5-carboxylate (P5C).
^Blumenkrantz, N.; Asboe-Hansen, G. (1975). "An assay for hydroxyproline and proline on one sample and a simplified method for hydroxyproline". Analytical Biochemistry. 63 (2): 331–340.
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^Maruyama, S; Miyoshi, S; Nomura, G; Suzuki, M; Tanaka, H; Maeda, H (1993). "Specificity for various imino-acid-residues of a proline-specific dipeptidylcarboxypeptidase from a Streptomyces species". Biochim Biophys Acta. 1162 (1–2): 72–76.
doi:
10.1016/0167-4838(93)90129-f.
PMID8448197.