|Molar mass||544.6 g/mol|
|Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)|
|(what is: / ?)|
Scytonemin is a biological pigment synthesized by many strains of cyanobacteria, including Calothrix sp., Lyngbya aestuarii, and others. It was originally discovered in 1849, although the structure remained unsolved until 1993. Scytonemin is believed to act as a bacterial sunscreen with a broad absorption from 325-425 nm and a separate maxima at 250 nm, and its biosynthesis triggered by exposure to UV light.
The biosynthesis in Lyngbya aestuarii was recently explored by Balskus, Case, and Walsh. It proceeds by the conversion of L-tryptophan to 3-indole pyruvic acid, followed by coupling to p-hydroxyphenylpyruvic acid. Cyclization of the resultant β-ketoacid yields a tricyclic ketone. Oxidation and dimerization yields the completed natural product. Three scytonemin biosynthetic enzymes are necessary, denoted as ScyA-C.
- "Scytonemin CAS (152075-98-4)". Santa Cruz Biotechnology, Inc. Retrieved 2011-05-30.
- Dillon, Jesse G.; Castenholz, Richard W. (2003). "The synthesis of the UV-screening pigment, scytonemin, and photosynthetic performance in isolates from closely related natural populations of cyanobacteria (Calothrix sp.)". Environmental Microbiology 5 (6): 484–91. doi:10.1046/j.1462-2920.2003.00436.x. PMID 12755715.
- Balskus, Emily P.; Case, Rebecca J.; Walsh, Christopher T. (2011). "The biosynthesis of cyanobacterial sunscreen scytonemin in intertidal microbial mat communities". FEMS Microbiology Ecology: 1–11. doi:10.1111/j.1574-6941.2011.01113.x.
- Proteau, P. J.; Gerwick, W. H.; Garcia-Pichel, F.; Castenholz, R. (1993). "The structure of scytonemin, an ultraviolet sunscreen pigment from the sheaths of cyanobacteria". Experientia 49 (9): 825–9. doi:10.1007/BF01923559. PMID 8405307.
- M. Bandaranayake, Wickramasinghe (1998). "Mycosporines: are they nature’s sunscreens?". Natural Product Reports 15 (2): 159–72. doi:10.1039/A815159Y. PMID 9586224.