Biomolecules 1

• DNA = deoxyribose nucleic acid

  RNA = ribonucleic acid
• nucleotide structure

  5-Carbon sugar

  Nitrogenous base

  Phosphate
• pyrimidines 


  thymine, cytosine

  single ring base
• purines 


  adenine, Guanine

  double ring base
• DNA to mRNA (transcription)


  Initiation

  Elongation

  Termination
• mRNA to Protein

  Translation
• amino acids are building blocks of proteins
• structure of amino acid

  carboxylic group

  R side chain

  amino group
• post translation modifications

  phosphorylated

  glycosylated

  nitrosylated
• post translation modifications

  involves attaching functional groups to amino acids altering protein function and increasing proteome diversity
• common post translation modifications

  phosphorylation + phosphate = phosphoprotein

  glycosylation + sugar group = glycoprotein
• native conformation of proteins

  the fully folded unique 3D structure of a protein determines its biological function

  e.g. enzymatic activity, protection, regulation,
• • Primary: Sequence of amino acids in a polypeptide chain.
• • Secondary: Local folding into a-helices and b-sheets.
• • Tertiary: Overall 3D shape of a single polypeptide chain.
• • Quaternary: Arrangement of multiple polypeptide subunits
• Classification of Amino Acids

  • Non-polar: Hydrophobic side chains (e.g., valine, leucine).
  • Polar: Hydrophilic side chains (e.g., serine, threonine).
  • Acidic: Negatively charged side chains (e.g., aspartic acid).
  • Basic: Positively charged side chains (e.g., lysine)78.
• • Translation: mRNA is translated into a polypeptide chain at the ribosome.
  • Transcription: DNA is transcribed into messenger RNA (mRNA) in the nucleus.
  • Protein Synthesis: The polypeptide chain folds into a functional protein