Download Chapter 18 Naturally Occurring Nitrogen

Chapter 18
Naturally 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
Chapter 18
Naturally 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