Spatial variability in secondary metabolite production by the tropical red alga Portieria hornemannii

• Published in: Hydrobiologia Vol. 398-399; pp. 263 - 273
• Main Authors: Matlock, Daniel B, Ginsburg, David W, Paul, Valerie J
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.04.1999
• Subjects: Algae; Beaches; Genetic factors; Marianas, Guam; Marine; Metabolites; Monoterpenes; Portieria hornemannii; Secondary metabolites; ISEW, Marianas, Guam
• ISSN: 0018-8158; 1573-5117
• DOI: 10.1023/A:1017003522096

Apakaochtodenes A and B, which are halogenated monoterpenes and the major secondary metabolites in Portieria hornemannii, are effective feeding deterrents toward herbivorous reef fishes on Guam. A reciprocal transplant study was conducted to determine the relative importance of environmental versus genetic factors influencing site-to-site differences in the amount of apakaochtodenes produced. The study sites were chosen for characteristically high (Anae Island) and low (Gun Beach) apakaochtodene levels. Algae collected from Anae Island and Gun Beach differed significantly in concentrations of apakaochtodene B at the start of the experiment, but by the end they had almost the same amount of the metabolite because the level had decreased in plants at Anae Island. Additionally, algae from Anae Island had relatively high levels of apakaochtodene A (60-90% of apakaochtodene B concentration), whereas this compound was rarely detected in Gun Beach algae. Transplantation t o a different site had no significant effect on the levels of the apakaochtodenes, other than a decrease in concentration that might have resulted from handling the algae. Our data indicate a strong site-to-site difference in apakaochtodene levels in P. hornemannii on Guam, notable interplant variation in the levels of the compounds among thalli within the same site, and some evidence for temporal variation in levels of these compounds over a period of four weeks.[PUBLICATION ABSTRACT]