Organic Chem: Biochemistry
Biochemistry• Study of chem of living organisms
• Most: large, complex molecules
• complex molecules: biopolymers smaller, simpler
units: monomers
4 main classes:
1. lipids
2. Proteins
3. Carbohydrates
4. nucleic acids2
Lipids• Fatty acids, fats, oils, phospholipids,
glycolipids, some vitamins, steroids, and waxes
3
• Structural part of cell membrane• Long-term energy storage• Insulation & shock absorbing
Carbohydrates: it’s all in the name!
-ose: fructose, glucose, maltose, lactose, galactose, sucrose, etc.
An aldehyde sugar = aldose 6 C sugar = hexose
What other functional groups
do you see?
A ketone sugar = ketose 6 C sugar = hexose
Structural isomer
Which atoms could be chiral?
Reminder: 4 diff groups
on a central C
Aldehyde double bond breaks and O atom transfers over H.
O then can form 2 single bonds to hold the ring
Intramolecular Reaction of Glucose to Form a Ring
Condensation Rxtn
Hydrolysis:
Proteins: the main molecule of living tissue
All 20 aa’s are chiral except for Glycine.
Amino acids
link together in condensation reactions to
form polymers.
Zwitterion
Condensation rxtn Forms C to N peptide bond
201 = 20 amino acids
202= 400 dipeptides
203 = 8000 tripeptide
20100= 1.3 x 10130
Oligopeptide = short to medium-length aa chain (5 to100 aa’s) fuzzy borders
Polypeptide = over 100 aa’s in the chain
A thiol (same family as O)
Can form disulfide bonds
Strong covalent bonds
Weak, but plentiful H bondse.g. wool
Not as stretchy: e.g. silk
Proteins play many roles in cells:
• structural (e.g. collagen in connective tissue)
• movement (e.g. actin & myosin in muscles)
• transport (e.g. hemoglobin, LDL, HDL)
• catalysis (e.g. wide variety of enzymes)
• regulation (e.g. hormones such as insulin)
Nucleic acids: energy and genetics
BASE vs.
NUCLEOSIDE (base + sugar) vs.
NUCLEOTIDE (base + sugar + phosphate)
RNA’s base
DNA vs RNA structure
Composed of nucleotide monomers:A 5 C sugar, a phosphate,
and nitrogenous bases:
Watson & Crick back in the 1950’s
Modern genetic engineering
Rosalind Franklin