Food Substrates and Digestive Capabilitites of Marine Deposit Feeders

海洋沉积物饲养者的食物基质和消化能力

• 批准号: 9618552
• 负责人: Lawrence Mayer
• 金额: $ 23.82万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-04-01 至 2002-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9618552&HistoricalAwards=false
• 关键词: Food; Substrates; Digestive; Capabilitites; Marine

9618552 Mayer 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.

9618552 Mayer Deposit 进料器在确定有机材料是否脱矿质或掩埋方面发挥着多种重要作用。 这些动物的作用是使表面可供微生物生长，并以远远超过沉积的速度在海底水平和垂直移动颗粒。 了解存款供给者的核心问题是识别它们使用的材料并确定这些材料的来源。 该项目的跨学科方法是将消化的化学反应器理论与酶促可用氨基酸的加工测量相结合，重点关注肠道中的水解率和吸收率。 将开发体外和体内荧光方法来测定小型沉积物饲养者肠道内的酶活性；这些方法也适用于浮游动物。 将进行化学分析和沉积物生物测定，以测试蛋氨酸或其他必需氨基酸在成岩作用的实验室模拟中是否变得更加有限。 在浅潮下区，将测试海参类加州拟刺参仅限于在蛋氨酸浓度相对较高期间进食的假设。 在 200 米深的地点，将测试穴居海胆 Brisaster latifrons 在春季开花后比冬季表现出更强的氨基酸水解和吸收能力的假设。