L10 - The Pyruvate Dehydrogenase Complex

Once pyruvate is generated from glycolysis, it's going to be moved to the matrix of the mitochondria via

a mitochondrial pyruvate carrier to be processed further by the pyruvate dehydrogenase complex

E1 coenzyme

Thiamine pyrophosphate (TPP) required as a coenzyme

E2 coenzyme and cofactor

Coenzyme A (CoA-SH) and Lipoic acid (lipoate) required

E3 cofactors

FAD and NAD required

E1 and E2 generated the

acetyl coA product of the reaction

E3 is going to perform

some redox recycling sort of reactions

Several or one subunits in PDH

several

Overall reaction has a large

negative delta G

TPP is derived from

vitamin B1

Most activity of TPP comes from the

thiazolium ring

Thiamine deficiency causes

beriberi disease

Coenzyme A has a reactive

thiol group

CoA-SH is when it is not engaged in

a thiol ester bond

CoA-SH primary role is to be an

acyl carrier and carries acetyl-CoA

CoA-SH derives from

vitamin B5

CoA-SH is a cofactor and required for

energy conservation in TCA

Lipoic acid provide a

reactive disulfide

Lipoic acid goes from its oxidized to reduced form to act as an

acyl carrier

FAD comes in what forms

dinucleotide (FAD) and mononucleotide (FMN) forms

FAD is derived from

vitamin B2

FAD is _____ bound to proteins. Proteins will be considered flavoproteins

covalently

FAD and FMN are typically bound to

proteins

_____ is the precursor to FAD and FMN, both of which are tightly associated with enzymes that catalyze redox reaction.

Riboflavin

________________ are mobile and can move freely and can engage in redox reactions

NAD+, NADH, NADPH

FAD and FMN are tightly bound to _____

enzymes

FAD is reduced to FADH2 in ___ steps

two

NAD+ is derived from

niacin or vitamin B3

NADP+ is phosphorylated form of

NAD+

NAD+ accepts two hydride ion transfers to be reduced to

NADH

PDH is located in the

mitochondria

PDH contains multiple copies of

E1, E2, and E3

PDH is inhibited by

ATP and products: Acetyl-CoA and NADH

PDH is activated by

AMP, CoA-SH and NAD+

___ inactivates PDH

PDK

___ activates PDH

PDP

high ATP will allosterically ____ the activity of PDK

initiate

Insulin signalling will ____ PDP

activate

insulin and liver and adipose tissue will activate the PDH complex by activating the

PDP

Glucagon does OR does not impact PDH

DOES NOT