Ch05pt1 - Myoglobin Protein Function Myoglobin and Hemoglobin Chapter 5 5-3 Myoglobin ferrous state Fe 2 Heme porphyrin 5-3 5-1 His-93(F8 His-64(E7

This preview shows pages 1–3. Sign up to view the full content.

1 Protein Function Myoglobin and Hemoglobin Chapter 5 5-3 Myoglobin 5-3 Myoglobin 5-1 Heme porphyrin ferrous state, Fe +2 5-3, 2 His-93 (F8) His-64 (E7) His-93 (F8) 5-5

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

View Full Document
2 His F8 5-11 Look at oxygen binding properties of Mb quantitatively: 1. For any reversible protein-ligand binding interaction: P + L PL PL P + L i.e. K dn = 1 K an K an = [ PL ] [ P ][ L ] (M -1 units) K dn = [ P ][ L ] [ PL ] (M units) 2. Fraction of ligand-binding sites occupied by ligand, or fractional saturation , = θ (theta): = [ bindingsitesoccupied ] [ totalbindingsites ] = [ PL ] [ P ] + [ PL ] = [ L ] K dn + [ L ] plot θ vs [L] hyperbola and substitute into equation for and simplify: rearrange K dn equation: [ PL ] = [ P ][ L ] K dn = [ L ] K dn + [ L ] x = y y + z 5-4a Lower K dn means sites fill at lower concentration of ligand, i.e. sites bind L with higher affinity. Low K dn = high affinity High K dn = low affinity = pO 2 P 50 + pO 2 = [ O 2 ] K dn + [ O 2 ] = [ O 2 ] [ O
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 05/04/2010 for the course CH 53890 taught by Professor Raymonds during the Spring '09 term at University of Texas at Austin.

Page1 / 4

Ch05pt1 - Myoglobin Protein Function Myoglobin and Hemoglobin Chapter 5 5-3 Myoglobin ferrous state Fe 2 Heme porphyrin 5-3 5-1 His-93(F8 His-64(E7

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online