(full paper is archived in the Miller Library)
Title: Nitrogenous waste products and excretory enzymes in the marine polychaete Cirriformia spirabrancha (Moore, 1904)
Student Author(s): Hult, James E.
Faculty Advisor(s): Phillips, John
%E Epel, Dave
Location: Final Papers Biology 175H
Date: June 1968
Keywords: Polychaete worm
Abstract: 1. C. spirabrancha primarily excretes ammonia, along with trace amounts of urea and taurine. No amino acids were found to be excreted. 2. Studies of uricase, allantoinase, allantoicase, and urease suggest that the ammonia primarily results from a uricolytic pathway. 3. The presence of ornithine transcarbamylase, argininoguccinate lyase, arginase and citruline in the tissues strongly suggest a functional ornithine-urea cycle. 4. Glutamine-like labile amides present in the greatest amounts in the tissues associated with excretion support the idea that amino acid deamination may also play a role in the formation of ammonia. 5. The rate of ammonia excretion in this sedentary polychaete is relatively constant. 6. The ammonia content of aqueous gut contents is very low, which suggests that there is no enteronephric excretion. 7. The most probable sites of excretion are the tentacles and, to a lesser extent, the anterior body wall, which contains a single pair of large nephridia. This hypothesis is supported by biochemical assays done on the tissues, by behavioral studies, and by descriptive anatomy of the nephridia. 8. Following inanition, the levels of ammonia and urea drop markedly in the tissues associated with excretion and maintain their levels in the tissues associated with the bulk of the catabolic machinery.
Notes: Publ 1969, Comp. Biochem. Physiol. 31: 15-24