Greetings. Welcome to this 17th lecture in our Principles of Biochemistry lecture series.
My name is Jerry Feigenson.
I'm a Professor in
the Department of Molecular Biology and Genetics at Cornell University in the USA.
In the 16th lecture,
you saw how hormonal control works together with
local control within each cell to regulate glycogen breakdown.
And you saw that hormone amplification can result
in as much as a million fold signal increase.
We examined how three particular enzymes of glycolysis are under control,
and we saw some very general principles of enzyme regulation.
In this lesson, you will learn that pyruvate,
which is the end product from glycolysis,
has several possible metabolic fates.
One that we will look at,
pyruvate can enter the mitochondrial matrix where it reacts to form acetyl-CoA.
The acetyl-CoA in the mitochondrial matrix is
completely oxidized to CO2 by the citric acid cycle.
Then we'll look at another kind of metabolism -
uptake of the fat we eat to the tissue is complex and not regulated.
Then we'll look at stored fat,
which releases fatty acid to the tissue in a highly organized process.
Fatty acids are completely oxidized in
the mitochondrial matrix by metabolism that we call β-oxidation.
And finally, we will look at ketone bodies that form from fatty acids.
These are useful fuels for brain and heart.