Mycosporine-like amino acid , MAA

The most common photoprotective sunscreens in many, but not all algal taxa and cyanobacteria are the mycosporine-like amino acids (MAAs), a suite of chemically closely related, colourless, water-soluble, polar and at cellular pH uncharged or zwitterionic amino acid derivatives (Fig. 13.4). 

Fig. 13.4 Chemical structure, absorption maximum and molar extinction coefficient of typical algal mycosporine-like amino acids (MAAs) and cyanobacterial scytonemin...

Karsten U, Friedl T, Schumann R, Hoyer K, Lembcke S (2005) Mycosporine-like amino acids (MAAs) and phylogenies in green algae Prasiola and its relatives from the Trebouxiophyceae (Chlorophyta). J Phycol 41 557-566... 

Sies H (1991) Oxidative stress oxidants and antioxidants. Academic Press, San Diego Shick JM (2004) The continuity and intensity of ultraviolet irradiation affect the kinetics of biosynthesis, accumulation, and conversion of mycosporine-like amino acids (MAAs) in the coral Stylophora pistillata. Limnol Oceanogr49 223-262 Shick JM, Dunlap WC (2002) Mycosporine-like amino acids and related gadusols biosynthesis, accumulation, and UV-protective functions in aquatic organisms. Annu Rev Physiol 64 223-262... 

Mycosporine-like Amino Acids (MAA) Small molecular weight organic compounds that absorb UV light and are thought to function as natural sunscreens. 

Across diverse taxonomic groups of marine organisms there are several classes of compounds that absorb UV and act as putative sunscreens. These include scytonemin (Figure 15.9), an extracellular cyanobacterial sheath pigment, and the mycosporine-like amino acids (MAAs, Figures 15.3-15.6) that are usually located intracellularly in cyanobacteria, algae, invertebrates, and fish. These compounds are the major focus of this chapter and will be discussed in detail below. 

Carroll, A. K. and Shick, J. M., Dietary accumulation of UV-absorbing mycosporine-like amino acids (MAAs) by the green sea urchin (Strongylocentrotus droebachiensis), Mar. Biol., 124, 561, 1996. 

Banaszak, A. T., Lesser, M. P., Kuffner, I. B., and Ondrusek, M., Relationship between ultraviolet (UV) radiation and mycosporine-like amino acids (MAAs) in marine organisms, Bull. Mar. Sci., 63, 617, 1998. 

A.T. Banaszak, T. LaJeunesse, R.K. Trench (2000). The synthesis of mycosporine-like amino acids (MAAs) by cultured, symbiotic dinoflagellates. J. Exp. Mar. Biol. Ecol, 249, 219-233. 

K. Whitehead, D. Karentz, J.I. Hedges (2001). Mycosporine-like amino acids (MAAs) in phytoplankton, a herbivorous pteropod (Limacina helicina), and its pteropod... 

D.S. Mason, F. Schafer, J.M. Shick, W.C. Dunlap (1998). Ultraviolet radiationabsorbing mycosporine-like amino acids (MAAs) are acquired from their diet by medaka fish Oryzias latipes) but not by SKH-1 hairless mice. Comp. Biochem. Physiol, 120A, 587-598. 

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