9711793 Lopez Deposit feeders play several important roles in determining whether organic material is demineralized or buried. These animals function to make surfaces available for microbial growth and move particles both horizontally and vertically within the seabed at a pace that far exceeds sedimentation. The central problem in understanding deposit feeders is to identify the materials that they utilize and to determine the sources of those materials. The interdisciplinary approach of this project is to combine a chemical reactor theory of digestion with measurements of the processing of enzymatically available amino acids, focusing on rates of hydrolysis in, and absorption from, the gut. In vitro and in vivo fluorometric methods will be developed to assay enzyme activity in the guts of small deposit feeders; these methods that will be applicable to planktonic animals as well. Chemical analyses and deposit-feeder bioassays will be conducted to test whether methionine or other essential amino acids become more limiting in laboratory simulations of diagenesis. In a shallow subtidal site the hypothesis that the holothuroid Parastichopus californicus is limited to feeding during times of relatively high methionine concentration will be tested. At a 200-m site the hypothesis that the burrowing urchin Brisaster latifrons will show greater hydrolytic and absorptive capacity for amino acids after the spring bloom than during winter will be tested.

Agency
National Science Foundation (NSF)
Institute
Division of Ocean Sciences (OCE)
Application #
9711793
Program Officer
Phillip R. Taylor
Project Start
Project End
Budget Start
1997-04-01
Budget End
2000-12-31
Support Year
Fiscal Year
1997
Total Cost
$136,037
Indirect Cost
Name
State University New York Stony Brook
Department
Type
DUNS #
City
Stony Brook
State
NY
Country
United States
Zip Code
11794