MFAC1501 Lecture Notes - Lecture 4: Starch, Anabolism, Oligosaccharide
28 May 2018
School
Department
Course
Professor
Biochemistry
Molecules of life
• Macromolecules = a large molecule formed by joining of smaller molecules, usually by a
dehydration reaction
• Polymers à type of macromolecule; consists of many similar or identical subunits (aka
monomers) linked tgt by covalent bonds
Macromolecule
Monomer (subunit)
Carbohydrates
Monosaccharides
Lipids
Glycerol and fatty acids
Proteins
Amino acids (aa)
Nucleic acids
Nucleotides
• Synthesis = dehydration reaction à removal of water molecule to form new covalent bond
• Breakdown = hydrolysis à addition of water molecule to break bond
• Proteins
- Around 100,000 diff proteins in a huan
- Classified according to structure and/or function
- Chain of aa form polypeptide à folding and formation of bonds à specific 3D conformation
à protein
- 20 aa that are the building blocks of proteins:
à structure of aa – amino grp + carboxyl grp + a H atom + variable side chain (R group)
à L and D isomers are mirror images of the same chemically structured aa (non superimposable on
each other); only L amino acids are constituents of proteins; note names of commercial aa
supplements eg L-Lysine, L-Trytophan etc
à chemical properties of proteins (and thus function) are determined by the R grp of the aa present
1. Non-polar
2. Polar
3. Acidic
4. Basic
5.
Primary
Secondary
Tertiary
Quaternary
Unique linear
sequence of aa.
Sequence is
determined by genetic
information
Refers to the local
regions of the
polypeptide chain that
are stabilized by H
bonding betw atoms
of the polypeptide
backbone
*Does not invove R
grp bonding
Types:
1. Alpha helix
2. Beta pleated
sheet
Folding of secondary
structure into a
specific 3D
conformation, held in
place by interactions
betw R groups
Association of 2 or
more polypeptides
(subunits)
à subunits can be
identical or different
à subunits usually
held tgt by non-
covalent bonds; which
allows structure
changes (KIV
enzymes)
Document Summary
Molecules of life: macromolecules = a large molecule formed by joining of smaller molecules, usually by a dehydration reaction, polymers type of macromolecule; consists of many similar or identical subunits (aka monomers) linked tgt by covalent bonds. Nucleotides: synthesis = dehydration reaction removal of water molecule to form new covalent bond, breakdown = hydrolysis addition of water molecule to break bond, proteins. Around 100,000 diff proteins in a huan. Chain of aa form polypeptide folding and formation of bonds specific 3d conformation. 20 aa that are the building blocks of proteins: Structure of aa amino grp + carboxyl grp + a h atom + variable side chain (r group) L and d isomers are mirror images of the same chemically structured aa (non superimposable on each other); only l amino acids are constituents of proteins; note names of commercial aa supplements eg l-lysine, l-trytophan etc.
