part 1

• Proteins


  Key structures found in all living things that are made up of chains of amino acids

  
• Amino acids that make up proteins

  • Carbon
  • Oxygen
  • Hydrogen
  • Sulfur
• Proteins come in a wide array of structures, each serving their unique functions
• Functions of proteins


  • Enzymes
  • Catalysts
  • Hormones
  • Providing structure
  • Transport
  • Defense
  • Contraction
  • Storage
• Simple proteins


  Yield only amino acids upon hydrolysis
• Conjugated proteins


  Yield other compounds aside from amino acids upon hydrolysis
• Fibrous proteins


  • Long polymer chains are arranged parallel or nearly parallel to one another to give long fibers or sheets
• Globular proteins


  • Fold back on themselves to produce compact, nearly spherical shapes
• Membrane proteins


  • Transport substances throughout the body in blood or lymph
• Functions of proteins


  • Enzymes
  • Hormones
  • Structure
  • Defense
  • Contraction
  • Storage
• Primary structure


  The sequence of amino acids in a polypeptide chain

  
• Peptide bond


  Covalent bond formed by linking of amino acids in a dehydration synthesis reaction

  
• Secondary structure


  Local folded structures that form within a polypeptide due to interactions between atoms of the backbone
• Tertiary structure


  The overall three-dimensional structure of a polypeptide
• Quaternary structure


  When a protein is made up of multiple polypeptide chains, also known as subunits

  
• Protein-protein interactions


  Physical contacts of high specificity established between two or more protein molecules as a result of biochemical events
• Complex formations


  Complex proteins made up of 2 or more polypeptide chains connected for a certain function
• Transcription


  1. Initiation

  2. Elongation

  3. Termination
• Pre-mRNA processing


  Modifications to the mRNA in eukaryotes before it is ready for translation, including addition of 5' cap, splicing, editing, and 3' polyadenylation
• Translation


  1. Initiation

  2. Elongation

  3. Termination
• Post-translational modifications


  • Glycosylation
  • Phosphorylation
  • Ubiquitination
  • Proteolysis
  • Protein methylation
  • Acetylation
  • Lipidation