Odd-numbered fatty acids do occur -- although in lower amounts than even-numbere
ID: 881623 • Letter: O
Question
Odd-numbered fatty acids do occur -- although in lower amounts than even-numbered fatty acids.
In the last step of beta-oxidation of an odd numbered fatty acyl CoA, propionyl CoA is produced.
What could this propionyl-CoA be used for in metabolism. As you answer (before you answer) look at p. 473.
A. Propionyl CoA has no metabolic use; it will simply be secreted since it cannot directly enter the citric acid cycle.
B. Propionyl CoA, after several steps, including steps in the citric acid cycle, gives rise to a compound that could enter gluconeogenesis.
C. Propionyl CoA could enter glycolysis.
D. Propionyl CoA could be reduced in size by 1 C atom and then enter citric acid cycle as acetylCoA.
Explanation / Answer
The corrcect ans is B.
B. Propionyl CoA, after several steps, including steps in the citric acid cycle, gives rise to a compound that could enter gluconeogenesis.
This acyl CoA, propionyl CoA is the last product of metabolism of odd-chain fatty acids, and is also a metabolite of mainly methyl-branched fatty acids. It is also the main metabolite of valine, and together with acyl CoA is a metabolite of isoleucine, with a methionine metabolite. acyl CoA, propionyl CoA is thus of huge importance as a glucose precursor.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.