BIOL 102 Lecture Notes - Lecture 6: Aromatic Amino Acids, Globular Protein, Enzyme
Document Summary
Proteins are the most diverse group of biological macromolecules; both chemically and functionally. Enzyme catalysis: (enzymes) enzymes are biological catalysts that facilitate specific chemical reactions; most enzymes are three-dimensional globular proteins that fit around molecules. Defense: (immunoglobulins, toxins, cell-surface antigens) other globular proteins use their shapes to recognize" foreign microbes and cancer cells. These cell-surface receptors form the core of the body"s endocrine and immune systems. Transport: (circulating transporters, membrane transporters) a variety of globular proteins transport small molecules and ions. Membrane transport proteins help move ions and molecules across the membrane. Support: (fibers) protein fibers play structural roles. These fibers include keratin in hair, fibrin in blood clots, and collagen. Collagen is the most abundant protein in a vertebrate body. Motion: (muscle) muscles contract through the sliding motion of two kinds of protein filaments: actin and myosin. Contractile proteins also play key roles in the cell"s cytoskeleton and in moving materials within cells.
