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Medical Term:


Pronunciation: sem′ē-al′dĕ-hīd

Definition: The monoaldehyde of a dicarboxylic acid, so called because half the COOH groups of the original acid are reduced to the aldehyde, whereas the other half are unchanged, glutamic acid γ-semialdehyde, OHC–CH2CH2CH(NH3)+–COO−. Many semialdehydes are intermediates in the biosynthesis and metabolic degradation of amino acid, l-proline, l-lysine, l-glutamate.