EXAM 2 BICH: Regulation of PDHC and TCA Flashcards

____undergo pyruvate dehydrogenase kinase (reversible phosphorylation II)

Pyruvate dehydrogenase kinase is allosterically

The serine residue of E1-PDH phosphorylated blocks

In regulation of pyruvate DH reaction, ______inactivates and _____activates

The reactivation of pyruvate dehydrogenase requires_____ in reversible____

-Allosterically activated by Ca²⁺(sends strong signal which causes muscle contractions)

- Hydrolyzes the phosphorylated serine in E1

- Remains associated as long as NADH/NAD⁺ and acetyl-CoA ratios are low

- High concentrations of NADH or Acetyl-coA inactivate the phosphatase and cause it to dissociate from the complex

The cascade of reactions stimulated by insulin binding to its receptors which activates pyruvate DH phosphatase which in turn activates pyruvate DH

When phosphatase is active, the serine of E1 is phosphorylated and converts

When phosphatase is inactive, the Pi on Ser of E1 does not allow for pyruvate to

Pyruvate dehydrogenase phosphatase turns on

Pyruvate dehydrogenase kinase turns on ____ and _____, and turns off ___ and ____.

The 3 reactions that are regulated in the TCA Cycle

-ATP, NADH, and succinyl-CoA inhibit

-Low energy

-ATP inhibits, ADP and NAD⁺ activate

-NADH and succinyl-CoA inhibit, AMP activate

-High energy signal

In the TCA cycle, NADH inhibits in:

In the TCA cycle, Acetyl-CoA inhibits:

In TCA cycle, citrate inhibits:

In TCA cycle, succinyl CoA inhibits:

In TCA cycle, ATP inhibits/ADP activates:

In the TCA cycle, Ca²⁺ activates:

Calcium signals____ ______ and thus production of ATP for fuel

PDHC is regulated by:

The proportional rate to oxygen consumption, NADH reoxidation, and ATP productions are

What do we see due to the TCA cycle?

The TCA cycle has no need for

Can all 20 common amino acids be made from metabolites derived from the TCA cycle

a-ketoglutarate can make

Succinyl CoA can be used to make

Fumarate and oxaloacetate can be used to make several

These enzymes catalyze reactions that replenish TCA cycle intermediates

What are the 3 filling up reactions in the TCA Cycle?

How does PEP carboxylase aid in the replenishment of intermediates in TCA cycle?

How does pyruvate carboxylase aid in the replenishment of intermediates in TCA cycle?

How does malic enzyme aid in the replenishment of intermediates in TCA cycle?

The ___ is impermeable to almost everything and has transporters

Pyruvate carboxylase occurs only in the

Because oxaloacetate cannot be transported across the mitochondrial membrane, it is reduced

Has 2 routes:

1. Aspartate aminotransferase: doesn't require NAD/NADH

2. Malate dehydrogenase: required NAD/NADH thus reducing equivalents can be transported across the IMM

What shuttle is this?

What shuttle is this?

-Electrons from NADH are transferred to FAD via a reaction catalyzed by 3-phosphoglycerol dehydrogenase

1. Ketone converted to OH in reduction as NADH is oxidized

2. OH converted back to ketone as FAD is reduced to FADH₂

3. FADH₂ part of flavoprotein dehydrogenase that transport 2e to the ETC

The ____ ______ offers a solution for plants, some bacteria, and algae.

Since plants can't accomplish efficient photosynthesis, they rely on

Net-synthesis of carbohydrates and other intermediates from acetate is not possible with TCA cycle

What are the short circuiting enzymes?

Understand cycle and what is this cycle?

Excess glucose and acetyl-CoA can easily be converted

Excess acetyl-CoA and most fatty acids can not support

Plants and some microbes can convert _______ but not humans