Spinach aldolase interactions with rabbit, chicken, and fish muscle phosphofructokinase-1

Previous studies showed that rabbit muscle phosphofructokinase-1 (PFK-1) activity losses due to dilution, due to inhibition by ascorbate, and due to some lithium salts were prevented by rabbit muscle aldolase. Chicken PFK-1 and fish PFK-1 interacted with ascorbate and were inhibited, consistent with a previously proposed function that ascorbate facilitates glycogen in resting muscle by inhibiting glycolysis. This report shows that a plant enzyme, spinach aldolase, has the same ability to prevent rabbit muscle PFK-1 activity loses as rabbit muscle aldolase and in some instances it was a better protector from activity losses than rabbit aldolase. Spinach aldolase also protected chicken and fish PFK-1s from inhibitions by ascorbate and from activity losses due to dilution. Prevention of losses PFK-1 activities from animal species by a plant protein, spinach aldolase, suggests an evolutionary conservative relationship between PFK-1s and aldolases.