3 Flashcards
which fibrous proteins features alpha helices
alpha keratin
which fibrous proteins feature beta sheets
fibroin and beta-keratin
which fibrous proteins feature collagen helices
collagen
what are alpha keratins enriched for
alanine and cysteine
describe the chains in the dimer of an alpha keratin
two chains in a dimer are twisted into a left-handed coiled coil superhelix
describe the structure of collagen (4)
three residues per time
interchain H-bonds
3 chains assemble into a right-handed super helix
left handed
what is the primary structure of collagen composed of
glycine-proline- hydroxyproline
what are collagen chains rich in
glycine, proline, 4-hydroxyproline, 5-hydroxylysine
where does the hydrogen bonding occur in collagen triple helices
between not within
what does synthesis of 4-hydroxyproline require
vitamin c
how does cross-linking occur in collagen helices
lysine, hydroxylysine, histidine
what are similarities between soluble globular proteins (4)
mixture of secondary (regular and irregular)
hydophobic core
closely packed interiors
max H-bonds in interior
what are differences between soluble globular proteins (3)
secondary strucuture composition
prosthetic groups
disulfides
what are the rules for soluble globular proteins (4)
2 layers to bury the hydrophobic interior
within secondary not between
no knots
close in primary = close in tertiary
right-handed connections between beta parallel
what are the 3 classifcation systems
SCOPE Pfam CATH`
