Bio Chem Kinetics

73 terms by kao327

Create a new folder

Advertisement Upgrade to remove ads

Kinetics

the rate of enzyme catalyzed rxn/ how fast or slow

Why is kinetics important?

the rate of enzmyes with different substraes is imporatnat for drug desgn (in the presences of inhibitor)

Ex of enzymes that want to slow down a rxn?

Lipitor

Ex of drugs that want to stop rxn?

Anticancer and antibiotics

What does the michaelis-mention eq do?

explains what you see experimentally when you do an enzyme catalzyed rxn

What does the horizontal slope of the hyperbola graph of MandM Equation stand for?

Vmax meaning its going as fast as it can go and its saturated

What type of dependence does Vo have on [S]? Meaning as [S] increase, what happens toVo?

Zero order, no change to Vo

What is the bottom linear line represent of the MandM eq in terms of dependency?meaning?

Represents the 1st order dependency of Vo on [S] meaning as [s} increase the Vo increases

What is Km?

Michalis constant, interms of CONCENTRATION where you are AT 1/2 vmax

What is Vo?

Measure of initial rate (first 10% of the rxn)

Why do you only look at the 1st 10% of the rxn?

To ignor the back reaction

What is the M and M equation (Michaelis Menten Eq)

Vo= (Vmas x [S]) / (Km + [S])

Whats the new equation as [S]<<<Km? And why/

(Vmax/Km)x (S) because the bottom S becomes negligable

What does the equation (Vmax/Km)xS represent in the graph and what conditions are these?

Corresponds to the First bottom Linear line when [S] <<< Km (Shows 1st order of dependence)

What is the equation when S>>>Km? and Why?

Vo=Vmax because the Km value is negligable

What does the equation Vo=Vmax represent on the M and M graoh?

Represents the horizontal linear line for Vmax

What does the eq Vo=Vmax say about the dependency?

There is no dependence of rate of Vo on S

What are the units associated with Km?

uM or mM or M

What does the Km gauge?

Gauges how tightly an enzyme binds its substrate

What does a low Km mean?

Binds substrate more tightly to the enzyme making it prcocess less substrates

What kind of saturation is associated with low Km?

readily saturate

What does a high Km mean?

binds the substrate more losely to the enzyme so process more substrates/metabolites

What type of saturation is associated with a high Km?

Its more readily saturated

What type of Km represents the "on" switch?

High Km process more substrate

What kinetic parameter can be a way of regulating a rxn?

adjusting the Km values

What values can enzymes change in response to some bio happenings?

Km valuse because in the same rxn you can have different Kms

What do both hexokinase and gluockinase do?

Put phosphate on glucose

Where is hexokinase and glucokinase found?

Hexo is found everywhere BUT the liver and gluco is found in the LIver

What type of Km values do hexokinase and glucokinase have?

HExo=Low Km (Proocess less and "sucks up" ess glucose) Gluco=High KM (sucks up excess glucose

Kcat/Km

specificty constant- takes into account BINDING and TURN oVer

What does Kcat take into account?

Turn over ONLY

What does Kcat/Km give an indicator for?

how fast the product is formed from the E+S free in solution

What does Kcat/Km help determine?

Which substrate is better for an enzyme if there is more than one substrate

What valuse of Kcat/Km indicates the best substrate?

HIGH kcat/km

Types of bonds found in Reversible and Irreversible inhibtition

Irriversible DOES have covalent bonds btween the E and the inhibitor when eversible doesnt

What types of inhibitor is 5 Florouricil? and what does it inhibit?

Irreversible ihinibitor of thymidylate synthease

What type of inhibitor is Methlytrexate and what does it inhibit?

Reversible inhibitor of dihydrolate reductase

What do Methlytrexate and 5 Florouricil do?

interphere with DNA synthesis in papidly growin cells including hair and stomach cells

What does the line weaver burk plot do?

Makes the M and M graph linear and makes it easier to read

What is the slope of the Line Weaver Burk Plot?

Km/Vmax

What is the Y intercept of Line Weaver Burk Plot?

1/Vmax

What is the lable for the Y intercept of Line Weaver Burk Plot?

1/vO

What is the Xintercept for the Line Weaver Burk Plot?

-1/km

what is the x lable for the Line Weaver Burk Plot?

1/[s]

What is the Line Weaver Burk Plot equation?

(1/Vo)= (Km/Vmax) (1/s) + (1/Vmax)

What type of inhibitor is a competive inhibitor?

Reversible

What doe competivite inhibitors resemble?

Substrate

Where do competive inhibitor bind?

at the active site BUT are NOT processed- just block the actie ste

What changes and stays the same as the amount of competive inhibitor is increase?

(1/vmax) is constant and (-1/Km) becaome less negative/increases [Kapparent increases)

Why does V max remain constant?

Because if there is a ridiculous high amt of substrate, then the competive inhibitor is going to basically not beat out all the substrates for the active site- therefore the inhibitor is diluted out

Why does K Apparent Increase?

An inhibitor slows or stops the enzymative process therefore Vo is slow and it takes more [S] to get to 1/s of the Vmax- As more and more inhibiotr is added- the steeper the line gets thereforeless substrate is needed to get to half of vmax (look at graph)

what is Ki?

Inhibition constant

What does a low Ki mean for potency?

Lower ki is more potent INHIBITOR

What does a high Ki mean for potency?

Less potent inhibitor

What is an example of a Competive inhibitor? Why?

Malanate competetively inhibits Succinate because of its similar structioe

What does K cat tell you?

how fast an enzyme can go when its compelety saturated with substrate aka its the Vo value of Vmax's point on the graph

How do you determine the location of vmax?

multiply Km by 10= vmax

Equation for Kcat

Kcat=Vmax/Et where Et=total concentration of enzymes

What part of the equilibrium equation is Kcat enzymes?

In the **ES**--> E + P part bc Kcat measures how fast ES complex breaks down (aka turn over)

What units are associated with Kcat? what do these tell you

min-1 or sec -1- tells you the number of moles of S converted to P/ unity of time divided by the moles of E

What does it mean when ACh estrace has a high Kcat?

it breaks down ACh very fast and has a high turn over

What ist he second ex of comeptitve inhibition?

Iondol inhibiting Chymotrypsin

How are trp from peptide chain and Indole similar in the way they look?

The TRP of the peptide chain has a R group that IS indole

What is the cause when indole binds in chymotrypsins active site?

The peptide can't bind and be hydrolyzed (REMEMBER: chymotrypsin cleaves at Trp )

Wat is the third example of competitive inhibitor? (Make lots of money)

Zocor and Lipitor (-statin drugs) for the inhibition of HMG-COa

What do zocor and lipitor inhibit?

HMG-COa

What does HMG-COa do?

enzyme for biosynthesis of cholesterol

How do non competitive inhibitors differ from competitive?

DO NOT bind at active site or resemle substrate

Fxn of Non competitive inhibitors?

Interfere with enzyme- do NOT affect binding of enzyme

Frequency of non competitive inhibitors in drugs?

Not common- don't know where going to bind so hard to design

Describ the line weaver burke plot for Non Competitive inhibitors?

Km is Constant, (1/vmax) increases and Vmax decreases

Analogy Whitman used for NCI?

Sticking stick in bike wheel

What are ex of NCI drugs? What is inhibited?

Treating Aids- inhibits reverse transcriptase

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set