kreb cycle

how is NADH created in pyruvate oxidation

extra electrons from pyruvate will reduce to NADH

what is the first reactant of the kreb cycle

acetyl coa

where is pyruvate transferred

into the intermembrane space that close to the matrix

what converts pyruvate into acetyl coa

pryuvate dehydrogenase

what is in the cristae membrane

where the electron transport chain, and enzymes of oxidative phosphorylation such as ATP synthase and succinate dehydrogenase are located.

what happens once the pyruvates make it into the intermembrane space?

pyruvates are pumped (active transport) into the matrix

what is the mintochondrial matrix

the innermost compartment of the mitochondria

how can pyruvates be resynthesized?

it can be resynthesized from a 4-carbon sugar oxaloacetate or malate that can be used in the kreb cycle

what can pyruvate be transformed into and why

pyruvate can transform into oxaloacetate or malate since it’s a reversible reaction. the same way those two sugars can tranform into pyruvate

what is the enzyme that converts pyruvate into oxaloacetate

pyruvate carboxylase

is the beginning of the kreb cycle reaction catabolic or anabolic

anabolic becuase it creates somethign

what is special about pyruvate

it can be turned into acetyl coa or oxaloacetate depending on what the cell needs. if it needs more acetyl coa it will form that and vise versa

what determines what pyruvate will convert into

depends on what enzyme is catalyzing the reaction, which substrates are present and at what concentrations

what is the pyruvate shuttle and example of

symporter cotransport

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pyruvate along gradient for H+ gradient and into intermembrane space

what is acetyl coa made of

acetyl and coenzyme A

what group is acetyl?

functional group

what class are coemzymes apart of

class of molecule typically derived from vitamins

what is coenzyme A derived from

vitamin B5 with a key component of panthothenic acid

what happens if u don’t consume enough B5

you won’t be able to synthesize coenzyme A and continue on with the kreb cycle

what is produced in the kreb cycle

6 NADH molecules for every 2 Aceytl CoA (two enter the mitochondria at once since there’s two pyruvates)

2 FADH2

4CO2 as byproducts

2 ATP per 2 Acetyl CoA

what is the significance of the products of reaction 8

they are the reactants of reaction 1

what is formed after combining acetyl coa and oxaloacetate

citric acid: 6 carbon sugar

what is the process of the kreb cycle

starts off as 6 carbon and slowly oxidizes itself until it produces oxaloacetate that will then be used for reaction 1 again

what is the overall purpose of the kreb cycle

to accumulate more electron carriers that can be used in oxidative phosphorylation since you’re not getting a lot of energy from this cycle

what are the irreversible reactions of the kreb cycle

reaction 1, 3, 4

what is the enzyme for reaction 1

citrate synthase

what happens in reaction 1

oxaloacetate combines with acytl coa to create citrate

why is reaction 1 irreversible

we would need a difference enxyme to break down citrate

what is the enzyme in reaction 3

isocitrate dehydrogenase which is isomer of citrate

what happens in reaction 3 and what does the enzyme do

removes hydrogen

catabolic

isocitrate oxidizes while NAD+ reduces and creates alpha-ketoglutarate, NADH, and CO2

what is the complex in reaction 4

alpha-ketoglutarate dehydrogenase complex

what happens in reaction 4

alpha-ketoglutarate is oxidized to succinyl-CoA and NADH and CO2 are produced

structure of citrate

structure of alpha-ketoglutarase

three separate proteins they don’t combine to make a quaternary structure

what type of pathway is the kreb cycle

amphibolic which means it has both catabolic and anabolic reactions

which reaction is anabolic

reaction 1

which reaction is catabolic

reaction 3 and 4

what is special about the intermediates of the kreb cycle

that can be used for other reactions such as amino acid synethesis

what is a specific example of an offshoot of the kreb cycle

fatty acid break down

where are most of the fatty acids broken down and why

in the mitochondria because the products of the fatty acid breakdown are useful in the kreb cycle

what else can be synthesized at the krebcycle

purines, pyrimadines, used for nucleic acids