110314 - Allosteric interactions (Chapter 10 382-396)...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
1 CHM3400 - Lecture 25 Mar 14 Allosteric interactions (Chapter 10 382-396) Non-Michaelis-Menten kinetics: hemoglobin Hill equation Models for cooperative binding: - concerted model - sequential model Different Conformation
Background image of page 1

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

View Full DocumentRight Arrow Icon
2 Hyperbolic vs. sigmoidal Initially slower kinetics Very fast increase in kinetics to reach V max
Background image of page 2
3 Myoglobin vs. hemoglobin O 2 binding Hyperbolic = Michaelis-Menten Sigmoidal = cooperativity
Background image of page 3

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

View Full DocumentRight Arrow Icon
4 Protein structures Myoglobin Hemoglobin Much more complex: two α and two β chain sub-units (tetramer), each containing a heme group. Relatively simple structure containing one heme group. O 2 binds non -cooperatively with myoglobin O 2 binding at one heme site changes overall structure (allosteric), and hence promotes binding at another site O 2 binds cooperatively with hemoglobin (= positive homo tropic cooperativity)
Background image of page 4
Physiological binding Bohr effect: decrease in pH decreases binding affinity of O 2 to hemoglobin Effect of 2,3-bisphosphoglycerate ( BPG ): BPG binds to hemoglobin without O 2 . Negative
Background image of page 5

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

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 13

110314 - Allosteric interactions (Chapter 10 382-396)...

This preview shows document pages 1 - 6. Sign up to view the full document.

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