Day 6 Flashcards
does size of peptide impact importance
no
contain permanently associated chemical components
conjugated proteins
non amino acid part of conjugated protein
prosthetic group
proteins containing lipids
lipoproteins
proteins containing sugars
glycoproteins
proteins containing specific metals
metalloproteins
covalent bonds linking amino acid residues in a polypeptide chain
primary structure
recurring structural patterns
secondary structure
3D folding of polypeptide
tertiary structure
2+ polypeptide subunits
quaternary structure
describes spatial arrangement of the main chain atoms in a segment of a polypeptide chain
secondary structure
common types of secondary structure
alpha helix, beta conformation, beta turn, random coils
how many atoms of the peptide group lie in a single plane
6
what prevents rotation
partial double bond character of c-n peptide bond
simplist arrangement, max number of hydrogen bonds
alpha helix
backbone wound around an imaginary longitudinal axis
alpha helix
r groups protrude in or out of the backbone in an alpha helix
out of
r groups protruding away from helical backbone
right handedness
most common handedness of alpha helix
right handed
less stable, not observed in proteins
left handedness
gives significant stability in amino terminus
intrahelical hydrogen bonds
what affects the stability of alpha helix
amino acid sequene
what can destabilize the alpha helix
charge, size, and shape of r groups
what can stabilize alpha helix
formation of ion pairs and hydrophobic effect
small electric dipoles in each peptide bond align thru what
hydrogen bonds
negatively charged amino acids often found where
near the NH3+ terminus
positively charged amino acids often found near where
near the COO- terminus
introduces destabilizing kink in helix
proline
what part of proline is part of rigid rign
nitrogen
high conformational flexibility, take up coiled strucutes
glycine
backbone extends into a zigzag, what conformation
beta conformation
single protein segment
beta strand
several stands in beta conformation side by side
beta sheet
adjacent polypeptide chains in a beta sheet can be what
antiparallel or parallel
opposite orientation
antiparallel
which occurs more freq, parallel or anitparallel
antiparallel
same orientation
parallel
connect ends of two adjacent segments of an antiparallel beta sheet
beta turn
how many residues involved in beta turn
4
hydrogen bond forms between what in a beta turn
first and fourth residue
which two amino acids ovten occur in beta turns
glycine and proline
