Temperature dependent filtration rates and 13C-NMR-enrichment analysis of substrate utilization in Pecten maximus
With the seawater temperature rising more than 1.5°C (IPCC) from the pre-industrial time, marine organisms are facing more and more severe climate changes. As temperature is an important factor influencing the physiology of animals, species specific adaptations has been well observed. Subtidal species are one of the most seawater temperature influenced animals. In previous researches, NMR metabolic profiling has been proved to be a decent technique of animal physiological studies. In this work, the king scallop, Pecten maximus was studied to test if (1) consuming labeled phytoplankton would be a stable way of 13C labeling marine filter feeders such as scallops; (2) the metabolism of P. maximus would also change with increasing temperature, which reflects as the different filtration rates from the outside and changing metabolic pathway inside organs. The scallop P. maximus were incubated under two different temperatures, 15°C and 20°C, fed with 13C labeled diatom Phaeodactylum tricornutum. After three days’ filtration rate measurement, the tissue samples of digestive gland and striated adductor muscle were dissected and extracted. Both qualitatively and quantitatively metabolic profiling was done via 13C NMR analyzation. The performance of experiment animal, Pecten maximus were quite different under two temperature treatments. Higher filtration rate was observed at 20°C whereas faster digestion and incorporation of algal lipids was also found inside the digestive gland from 20°C treatment. As for the muscle tissues, incorporation of 13C labeling was observed in both temperature groups, proving this labeling technique is applicable for marine filter feeders.