Memorizing Michaelis-Menten Help

[KoalaT]

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So I've learned this a million times and understand it all perfectly each time I review it. Yet I still have trouble remembering the differences in all the competitive, noncompetitive, uncompetitive, what their exact changes are, etc etc.

Anyone come up with a good mnemonic or memorization tool?

 

[aldol16]

What differences are you having trouble remembering? How they appear on a Lineweaver-Burke plot? Or something more fundamental?

I think of it in terms of a reaction diagram. Think of E + S -------> ES. "I" can bind at either "E" or "ES". If it binds at "E," then it's a competitive inhibitor. And since it's "competitive," that means that adding more substrate can displace it. Which means it has to be binding at the active site. If "I" binds only "ES" then it's uncompetitive. It's not competing with the substrate for anything. Then what else could you imagine? Well, the inhibitor could bind to both "E" and "ES." In that case, it's called mixed inhibition (mixed = combination of both competitive and uncompetitive). Finally, the harder one to remember is just a special case of a mixed inhibitor - it's the case where the inhibitor binds to "E" and "ES" with equal affinity and that's called non-competitive.

 

[To be MD]

So I've learned this a million times and understand it all perfectly each time I review it. Yet I still have trouble remembering the differences in all the competitive, noncompetitive, uncompetitive, what their exact changes are, etc etc.

Anyone come up with a good mnemonic or memorization tool?

Hey, the best way to understand the information is to understand (1) the axes and (2) apply how the changing Km or Vmax would do to the graph. This isn't intuitive because we're dealing with axes that are 1/Vmax and 1/, so the best way, I think, to see how each one of those changes applies is to see them changing on a graph.

Check out this website http://www.ucl.ac.uk/~ucbcdab/enzass/inhibition.htm#comp to see those graphs in action. It helped me ace Biochem last term because I knew what going up/down on the axes meant.

Sorry there's no mnemonic, but those are always better when you make them up yourself ^_^. EK's table at the end of their Bio Mol 1 Lecture is a good summary.

 

[Lillie.l]

A guy on YouTube, Mood university explains it really well. Maybe read about it and watch videos, make sure to understand it as well as the logic behind it. Then try to explain it with your own words. Review it daily.

Sent from my ASUS_Z00AD using Tapatalk

 

[Lillie.l]

A guy on YouTube, Mood university explains it really well. Maybe read about it and watch videos, make sure to understand it as well as the logic behind it. Then try to explain it with your own words. Review it daily.

Sent from my ASUS_Z00AD using Tapatalk

MOOF **

Sent from my ASUS_Z00AD using Tapatalk

 

[KoalaT]

Hey, the best way to understand the information is to understand (1) the axes and (2) apply how the changing Km or Vmax would do to the graph. This isn't intuitive because we're dealing with axes that are 1/Vmax and 1/, so the best way, I think, to see how each one of those changes applies is to see them changing on a graph.

Check out this website http://www.ucl.ac.uk/~ucbcdab/enzass/inhibition.htm#comp to see those graphs in action. It helped me ace Biochem last term because I knew what going up/down on the axes meant.

Sorry there's no mnemonic, but those are always better when you make them up yourself ^_^. EK's table at the end of their Bio Mol 1 Lecture is a good summary.

This is what actually worked the best for me: Simply visualizing the graphs and then using the graphs to apply the changes in Vmax and Km. I'm a very photographic memory kind of guy and simply picturing the graphs really helps the most. Previously I was trying to remember their changes in Km and Vmax, which can get all jumbled up when you're trying to recall them for each process. Simply recalling the graph is easy and works for all types.

These two graphs do wonders.
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/M/Michaelis_Menten2.gif (For traditional graphs)

http://guweb2.gonzaga.edu/faculty/cronk/CHEM440/images/inhibition_Lineweaver_Burk.gif (for lineweaver)

 

[Astra]

So this what you need to know:

Competitive inhibition: Higher Km, same Vmax

Non-competitive inhibition: same Km, lower Vmax

Mixed inhibition: mixed Km, smaller Vmax

Uncompetitive inhibition: Lower Km, Lower Vmax


The difference between non competitive and uncompetitive is the following:

Non competitive bind at an allosteric site. Uncompetitive bind the ENZYME AND SUBSTRATE together.

The way I remember it is that Uncompetitive starts with the letter "U". This looks like a a hand grabbing something which is what it does.