Proteins Flashcards
Biological roles of proteins include
Structure- collagen, keratin
Transport- membrane transport
What determines amino acid properties
Side chain R
What is the smallest amino acid to larger
Glycine, alanine, valine, leucine
Why are amino acid hydrophobic
CH3 doesn’t interact with water
Phenylanine is
Hydrophobic
Hydrophilic and charged amino acids
Aspartame
Glutamate
Asparagine
Glutamine
Serine
Cysteine can be used for
Disulfide bonds
Transmembrane proteins function
Move materials through bilayer
Special features of amino acids
Methionine- 1st amino acid in protein sequence determined by DNA start codin- ATG
Cytosine- disulphide bond formation
Amino acid modification is
Serine and threonine- due to hydroxyl group
O linked glycosylation
Reversible phosphorylation
Asparagine- N linked glycosylation
Proline- ring- forces bend in protein structure
Name of reaction of peptide bond formation
Condensation reaction
Can free rotation occur in peptide bond formation
Yeah
Amino acid sequence determines
Protein structure
IY structure is the only interaction between amino acids and
Peptide bond
What is secondary structure
Local structure of polypeptide chain
Bonding is due to hydrogen bonding- way protein starts to fold
Can secondary structure be easily broken
Alpha helix
Beta sheet
Alpha helix structure features
Rod like structure
Coiled peptide chain
R groups extend outwards from axis
H bonding between CO and NH4 residues away
Alpha helix is intertwined with
Myosin
Tropomyosin
Muscle fibrin in blood clots
Keratin in hair
Beta sheet features
Polypeptide chain is extended
H bonding between CO and NH on different polypeptide strands
Strands run parallel or anti parallel
Anti parallel strands connected by B turns
Silk strong structure