Ecobiochemical studies on the deep-water pelagic community of Korsfjorden,Western Norway. Adenine nucleotides in zooplankton

Adenine nucleotides of zooplankton were extracted from freeze-dried individuals killed in liquid nitrogen. 96% of the ATP in frozen samples stored at-26°C degraded to AMP in 8 days, while ATP was stable for the same period in freeze-dried samples. A strong metabolic stress caused by capturing the animals was evidenced by a marked lowering of the energy charge (ATP)+1/2(ADP)/(ATP)+(ADP)+(AMP)], the natural level of energy charge being restored in about 24 h. The concentration of ATP showed no significant correlation with the dry weight of the individuals of a species nor with the mean dry weight of the species. The ATP concentration showed marked seasonal changes with increasing values during periods of reproduction, which is assumed to reflect an inheretn seasonal rhythm in the metabolism. ATP cannot be used as a general estimator of metabolism as it did not reflect differences in metabolic activity between different-sized individuals or species. The mean energy charge for 13 species was 0.7.Contribution from the Biological Station, University of Bergen, N-5065 Blomsterdalen, Norway.