Biosynthetic Pathways of MAAs and their Regulatory Mechanisms

Abstract

The biosynthetic mechanism of mycosporine-like amino acids (MAAs) has been roughly elucidated. In 2010, the genes responsible for MAA biosynthesis were identified in cyanobacteria. In this chapter, first, we will describe the reaction mechanisms responsible for the biosynthetic pathways of MAAs, mainly based on results from cyanobacteria. Next, as a regulatory mechanism for MAA biosynthesis, the response patterns of MAA accumulation in response to abiotic stresses, such as UV irradiation, salt, and osmotic pressure, will be explained. There are many points to be clarified regarding the detailed regulatory mechanisms, and further analyses are awaited in the future. Because MAAs have useful activities in addition to UV absorption, they are substances that are expected to be used in cosmetics and pharmaceuticals. This chapter also includes discussions from the perspective of future industrial production.

Keywords: ATP-grasp enzyme, Biosynthetic pathways of MAAs, D-Ala-D-Ala ligase, Gene resources, Nonribosomal peptide synthetase (NRPS), Localization, Osmotic stress, Pentose phosphate pathway, Shikimate pathway, Regulatory mechanism, Substrate specificity, Salt stress, Temperature, UV irradiation, 4- deoxygadusol, 3-dehydroquinate synthase (DHQS), O–methyltransferase (O–MT), 2-epi-5-epi-valiolone synthase (EVS).