Question

how do acid hydrolases equalize the pH of the lysosome to that of the cytosol?

Answer 1

Hydrolytic enzymes are found in the membrane enclosed compartments known as lysosomes. These enzymes help in intracellular digestion of macromolecules. Inside lysosomes there are around 40 type of hydrolytic enzymes are present including phosphatase, glycosidases, sulfatases, nucleases, lypases etc., all are acid hydrolases. These enzymes work best under acidic environment, due to which lysosomes maintains a pH of 5, Whereas the pH of cytosol is around 7.2. These different pH levels maintained inside and outside the lysosomes by the presence of proton pumps(ATPases). These pumps are present on lysosomal membranes and gain energy for the active transport of H+ ions inside the lysosomes from ATP hydrolysis. This transfer of protons from cytosol to inside the lumen of lysosome help in balancing the pH of both inside and outside the lysosomes.