Energy 1-Pyruvate Oxidation

Pyruvate is techinally an intermediate step between what?

glycolysis and TCA Cycle(or citric acid cycle)

Under aerobic conditions, pyruvate from glycolysis is converted to ______ and _________________, which then enters the tricabocylic acid(TCA) cycle (aka Citric acid cycle).

CO2 and acetyl-CoA

The organelle has 2 membranes: an outer and inner one. They differ in permeabiltiy, which one has higher impermeabilty?

inner membrane

pyruvate crosses through mitochondria on the outer membrane via ____________ channels.

pyruvate crosses through mitochondira on the inner membrane via __________________.

non-selective channels; pyruvate translocase

within the mitochondiral matrix, pyruvate can either be carboxylated for:_____________

OR decarboxylated to continue in: _____________.

gluceoneogenesis or cellular respiration

what molecule does Acetyl-CoA come from?

CoASH

what does CoASH stand for or mean?

CoA= beggining of Acetyl-CoA

SH = sulfhydryl group

where do all the TCA cycle reactions and subsequent steps of aerobic metabolism take place?

mitochondria

the oxidative decarboxylation of _________ to Acetyl-CoA is the connecting link between glycolysis and TCA cycle.

pyruvate

oxidative decarboxylation of pyruvate is catalyzed by:

pyruvate dehydrogenase

pyruvate dehydrogenase complex(PDC) is formed from multiple copies of 3 enzymes:

*these are all involved in conversion of pyruvate to Acteyl-CoA

E1: pyruvate dehydrogenase

E2: dihydrolipoamide acetyltransferase

E3: dihydrolipoamide dehydrogenase

Eukaryotic PDC contains a unique subunit, termed E3BP(has no known enzymatic function). What does E3BP stand for?

“binding protein”

what is the name to one of the largest, multienzyme complexes.

• plays a huge role in energy metabolism

pyruvate dehydrogenase complex(PDC)

Vitamin B1 is crucial for energy ______________.

metabolism

what process regulates pyruvate oxidation?

allosteric inhibition by phosphorylation of serine residues on E1

what enzyme phosphorylates select serine residues on E1 for the regulation of pyruvate oxidation?

pyruvate dehydrogenase kinase(PDK)

The expression of pyruvate dehydrogenase increases or decreases during starvation?

increases

what enzyme stimulates pyruvate oxidation to regulate it?

phosphate dehydrogenase phosphatase(PDP)

what is the enzyme pyruvate dehydrogenase phosphatase stimulated by?

calcium and insulin