Smith, G. Moss Landing Marine Laboratories, 831-375-2614
Miller, P. E. Monterey Bay Aquarium Research Institute, pemiller@mbari.org

 
EVALUATION OF THE RELATIONSHIP BETWEEN DOMOIC ACID AND PROLINE METABOLISM IN PSEUDO-NITZSCHIA SPP. FROM MONTEREY BAY, CA.
 
The phenomenology of domoic acid (DA) production by toxic strains of the Pseudo-nitzschia species complex has received considerable attention, leading to the general observations that DA production is stimulated by growth limiting or stress conditions. The biochemical pathways to DA have been less well characterized. Several observations suggest a link between DA and proline metabolism. DA is a structural analogue of proline; enhancement of DA production in response to environmental stress also suggests a role as a functional analogue. Metabolic labeling studies indicate that DA is derived from two distinct metabolite pools comprising a geranyl- pyrophosphate-like moiety and a 3-hydroxyglutamic acid moiety (Douglas et al. 1992 J Chem Soc Chem Comm 9:714), 3-hydroxyproline could provide a precursor for the later compound. P. multiseries and P. australis strains isolated from Monterey Bay are characterized by lower free proline pools (0.5-1.0 mM) compared to other marine phytoplankton species (> 1.5 mM). DA production by these strains peaked as cells entered stationary phase, proline pools tracked this pattern. Isolates of P. australis exhibited up to 100-fold higher levels of DA accumulation than P. multiseries and DA:Proline molar ratios >1. The coordination of DA and proline metabolism in toxin producing species will be discussed. CS31 SS42 Oral / Poster
 
Day: Friday, Feb. 5
Time: 04:30 - 04:45pm
Location: Eldorado Hotel
 
Code: SS42FR0430E