Costa as a glycogen store and probable site of energy generation in Tritrichomonas foetus

Costae were isolated from the parasitic protozoan Tritrichomonas foetus and were found to contain 87% of the total cellular glycogen. Radiotracer studies, using [U-14C]glucose, were performed on starved and unstarved whole cells and on costae isolated from starved and unstarved cells. During cell starvation, catabolism of labeled costal glycogen was demonstrated. Preferential utilization by the cell of costal glycogen over other cellular glycogen stores was indicated.