Lesson 7 - Ligand Binding and Motor Proteins
Learning Objectives
You should be able to:
• Give characteristics of the five major functional classes of proteins
• Understand the molecular basis for specificity and reversibility of protein-ligand binding.
• Define KD and θ as they relate to binding proteins.
• Describe protein-ligand interactions mathematically and graphically.
• Explain how myosin structure relates to its function as a motor protein.
• Define the composition of thick and thin filaments in myofibrils.
• Describe the molecular basis for the sliding filament model of muscle contraction.
Textbook Reference
Text Chapter 6, Section 1, Section 2 (pp. 275-277) and Section 4
Vocabulary
• ligand
• KD
• binding curve
• globular protein
• prosthetic group
• conformation
• actin
• myosin
Lecture Slides (begin next page)
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©2025 Laura S. Zapanta, Ph.D. 1
,Pre-Class Renew
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, Biosc 1000 Spring 2025 2/4/2025
Motor Proteins
Lesson 7.2
Biosc 1000 – Lecture 7
February 4, 2025
7
7
Molecular motors are proteins that use ATP to produce
cyclic conformational changes.
garerend by ligands
12 bun
bind
release
8
8
©2025 Laura S. Zapanta, Ph.D. 2