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Old 02-03-2012
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Default enzyme kinetics

can anyone explain in simple language enzyme kinetics, km vmax and related graphs.
i never seem to get it.
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Old 02-03-2012
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Default hi

If you watch the videos of biochemistry this will help you alot

km substrate conc. required to produce half the maximum activity

and there is inverse relationship between KM and affinity

so if km high the affinity(activation) for subtrate is low because of that there

should be alot of subtrate conc. to do the effect.

there are two graphs michaelis-menten when km increase it will appear as

increase in x axis.

and km always will be Vmax divided by two.

in lineweaver-burk assume km was 1 then it increase to 2 so -.5 will be right

on x axis than -1

when km increase or decrease?this is in competitve inhibitor

ex. if there is drug work as competitive inhibitor you should increase the conc.

of subtrate due to decrease affinity so if conc. of subtrate increased it will

compete the drug.

Vmax number of enzyme and always related to word( induction) if there is

noncompetitve inhibitor(irreversible) so there is one or more site of enzymes

will lost so the result decrease in the number of enzymes this will appear on

Lineweaver-burk on the y axis as shifted upward why?assume if vmax was 2

then it decreased to 1 so .5 ahifted to 1 so increase.

And you should link this topic with pharmacology

hoping that I have simplified the concept,not complicated it .

waaaatch videos( Dr rayon in biochem).

good luck
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