# 7.3: Model Binding Systems

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Learning Objectives

• explain the similarities and differences in structure between myoglobin and hemoglobin in the deoxy and oxy states
• state structural features of Hb that stabilizes the deoxystate and the oxystate
• draw graphs of fractional saturation Y vs L (or pO2) for Mb and Hb (at different pHs and in the presence of CO2 for Hb) and explain their apparent similarities and differences
• draw a thermodynamic cycle for the interactions of O2, CO2 and H+ with deoxy-Hb and oxy-Hb
• explain how Hill Plot analysis can account for cooperative binding curves for Hb.
• give a simple explanation of the MWC model and draw cartoon representations of Hb in the T and R state, describing the characteristics of those states
• given definitions of the MWC parameters (L, KT, KR, c, and α) and the assumptions of the model, explain how this model accounts for cooperative sigmoidal binding curves for Hb and dioxygen.
• draw cartoon models and explain differences in lock and key, induced fit, and conformational selection as mechanisms for ligand bind.
• Explain biological advantages elicited on ligand binding by intrinsically disordered proteins

This page titled 7.3: Model Binding Systems is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Henry Jakubowski.