ch369_f09_enzymes_3_notes

ch369_f09_enzymes_3_notes - S tudy group tim s &...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
Extra office hours for the T.A.’s on Monday, Oct 5. Ken, 3- 4 pm in cubicle A, 1st floor of Welch. Cassidy, 11 - noon in 3.422F of MBB.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Plan for today is to finish chapter 7. Enzyme kinetics & enzyme inhibition.
Background image of page 2
Last time - Michaelis-Menten enzyme kinetics: [S] = initial substrate concentration, typically in units of moles/liter. v o = initial reaction velocity (such as moles of product produced / sec) The shape of the curve is described by the Michaelis- Menten eqn:
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
K M is the substrate concentration when the initial reaction velocity is one-half of its Three numbers that can describe an enzyme’s catalytic abilities are: K M and V max and k cat initial reaction velocity V 0 [S]
Background image of page 4
K M is a measure of how tightly an enzyme binds substrate. High K M means weak substrate binding ; Lower K M means tighter substrate binding.
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Another quantity used to characterize enzymes is k cat . k cat = V max / [E] total k cat is called “catalytic constant” or “turnover number”. k cat = number of catalytic cycles by each active site per second. Enzyme k cat Staph. nuclease 95 sec -1 Chymotrypsin 190 sec -1 Trios phosphate isomerase 4300 sec -1 Carbonic anhydrase 1,000,000 sec -1
Background image of page 6
Finding V max and K M : May use a “ Lineweaver-Burk plot
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Not all enzymes follow Michaelis-Menten kinetics. For example, some reactions have multiple steps and several transition states (these are not taken into account in the M-M model, which assumes one transition state).
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 32

ch369_f09_enzymes_3_notes - S tudy group tim s &...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online