Chapter 18 Naturally Occurring Nitrogen-Containing Compounds

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Chapter 18Naturally Occurring Nitrogen-Containing
Compounds

• Amino Acids Structure and Properties
• Hydrophobic, Hydrophilic, acidic and basic side
  groups
• Essential Amino acids - not synthesized in the
  body, must be ingested
• Non-essential Amino acids - synthesized
  internally
• Titration of Amino Acids

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Chapter 18Naturally Occurring Nitrogen-Containing
Compounds

• Amino Acids Structure and Properties
• Structure of Amino Acids (20 common amino acids
  found in proteins)
• hydrophobic side chain groups (nonpolar side
  chain)
• ala, gly, ile, met, phe, pro, trp, val
• hydrophilic side chain groups (polar side chain)
• asn, gln, ser, thr
• Acidic side chain groups
• asp, glu, cys, tyr
• Basic side chain groups
• arg, his, lys
• Properties of Amino Acids
• pKa of ?-CO2H, pKa of ?-NH3, pKa of side chain
  and isoelectric point called PI
• Electrophoresis -separation based on electric
  charge. Positive charged moves towards negative
  electrode and negative charged towards positive
  electrode