Abstract
Rabbit intestinal sucrase [EC 3. 2. 1] was purified by solubilization with papain or Triton X-100 followed by adsorption on Sephadex G-200 gel. Antibodies were developed in a goat against purified papain-solubilized sucrase and in guinea pigs against purified Triton-solubilized sucrase. Both antibodies precipitated microvillous membrane-bound sucrase and other hydrolases in a parallel manner, but did not precipitate solubilized hydrolases except sucrase, indicating that these microvillous hydrolases were located very close to each other and scattered on the microvillous membrane. The antibody to Triton-solubilized sucrase contained an antibody species which was not absorbed by microvillous membranes; it precipitated Triton-solubilized sucrase but not papain-solubilized sucrase. This same antibody species was not found in anti-papain-solubilized sucrase antibody. On the basis of these findings the state of sucrase molecules anchored in the microvillous membrane is discussed.
