Immune defense enzymes: Advances in L-amino acid oxidase of marine animals

L-amino acid oxidase (LAAO) is able to stereoselectively catalyse the deamination of L-amino acids to alpha-keto acids, ammonia and H2O2. It has been reported that this enzyme has biological functions including inhibition of bacteria and antiviral, anti-parasitic and anti-tumour activities. To date, marine animal LAAO are constantly being identified. L-amino acid oxidase derived from marine animals has been purified for Sebastes schlegelii, Platichthys stellatus, Gadus morhua, Signanus oramin, Aplysia californica and some others. In this paper, we review the reported progress of research on marine animal LAAO, including basic characteristics, tissue distribution and biological function. We intended to provide a reference for the further study of LAAO in marine animals.