The metabolic fate of fatty acids is dependent on two enzymes, carnitine acyltransferase l and acetyl-coa carboxylase. carnitine acyltransferase i facilitates the transport of fatty acids to the mitochondria for ? oxidation, whereas acetyl-coa carboxylase catalyzes the first reaction in the fatty acid synthesis pathway. the amp-activated protein kinase (ampk) regulates the activity of acetyl-coa carboxylase by phosphorylating a specific serine residue. a. mutation of this regulatory serine to alanine or aspartate would be expected to have different effects on the regulation of acetyl-coa carboxylase select the statements that describe the expected effects of mutations of the regulatory serine.
b. mutating the regulatory serine to aspartate will mimic the inhibitory effect of phosphoserine and shut down the activity of acetyl-coa carboxylase. if acetyl-coa carboxylase is inhibited malonyl-coa will not be synthesized, and ? oxidation of fatty acids will proceed uninhibited.
c. mutating the regulatory serine to alanine will inhibit acetyl-coa carboxylase, leading to a decrease in concentration of malonyl-coa. low levels of malonyl-coa mill inhibit the entry of fatty acids into the mitochondria and the ? oxidation of fatty acids
d. mutating the requlatory serine to alanine will have no effect on the regulation of acetyl-coa ? carboxylase by ampk active ampk inhibits acetyl-coa carboxylase, which allows ? oxidation of fatty acids to proceed uninhibited if the regulatory serine is mutated to alanine, then acetyl-coa carboxylase will be constantly turned on and will synthesize malonyl-coa· increased levels of malonyl-coa will shut down ? oxidation of fatty acids by inhibiting the entry of fatty acids into the mitochondria
e. if the regulatory serine is mutated to aspartate, acetyl-coa carboxylase will become constitutively active. malonyl coa, synthesized by acetyl-coa carboxylase, will activate the ? oxidation of fatty acids