Studies suggest that the incidence of colon cancer may be lowered with high fiber

The increase in the high fiber diet reduces the risk of colon cancer is suggested by the researchers. The effect of high fiber dietary intake add bulk to the digestive system. It also reduces the time required by the food to travel from the colon. Our food often contains some carcinogenic contents, so the interaction of such carcinogens may also be reduced due to the high fiber diet and also reduces the risk of intestinal tract. The bacteria in the lower intestine breaks the fibers into butyrate, which inhibits the growth of tumors of the colon and rectum.

a) The response indicates that a pH below or above this range will most likely cause enolase to denature/change its shape and be less efficient or unable to catalyze the reaction.

b)The response indicates that the appropriate negative control is to measure the reaction rate (at the varying substrate concentrations) without any enzyme present.

c)The response indicated that the enolase has a more stable/functional/correct/normal protein structure at the higher temperature of 55°C than at 37°C because the enzyme is from an organism that is adapted to growth at 55°C.

Explanation:

Enolase catalyzes the conversion of 2-phosphoglycerate to phosphoenolpyruvate during both glycolysis and gluconeogenesis.In bacteria, enolases are highly conserved enzymes and commonly exist as homodimers.

The temperature optimum for enolase catalysis was 80°C, close to the measured thermal stability of the protein which was determined to be 75°C, while the pH optimum for enzyme activity was 6.5. The specific activities of purified enolase determined at 25 and 80°C were 147 and 300 U mg−1 of protein, respectively. Km values for the 2-phosphoglycerate/phosphoenolpyruvate reaction determined at 25 and 80°C were 0.16 and 0.03 mM, respectively. The Km values for Mg2+ binding at these temperatures were 2.5 and 1.9 mM, respectively.

Enolase-1 from Chloroflexus aurantiacus (EnoCa), a thermophilic green non-sulfur bacterium that grows photosynthetically under anaerobic conditions. The biochemical and structural properties of enolase from C. aurantiacus are consistent with this being thermally adapted.