Proteins Flashcards
What type of collagens are type IV and VI
Network forming - important in basal Lamina
What type of collagens are type one, 2 and 3.
Fibril-forming
Type V, IX, XII collagens are what?
May be involved in cross linking. Fibril-associated collagens
What occurs after secretion during biosynthesis of collagen
Removal of extension peptides
Which two processes of collagen synthesis occur within fibroblasts.
Post translational modifications and pro collagen triple helical cable
What is the repeating sequence of collagen
Gly - X - Y. Gly occurs every third residue.
What is X often in the collagen sequence
X often Pro
What is Y often in collagen sequence.
Hyp
What is hydroxyproline involved in?
Hydroxyproline is involved in H - bond formation which stabilizes triple helix of collagen.
How is hydroxyproline formed.
Proline undergoes hydroxylation by enzyme prolyl hydroxylase which requires vitamin c as a co factor. (Ascorbic acid)
What is hydroxylysine used for in collagen
Hydroxylysine residues are attachment sites for sugar residues and are involved in cross linking between collagen chains
Where are gly, pro and hyp residues found in collagen.
Gly residues pack into the centre
Pro and Hyp residues are on the outside.
How is collage similar to the construction of a rope?
Fibres twisted in opposite directions
What do peptidase enzymes do in the assembly of collagen
Peptidase enzymes remove extension peptides after secretion into extra cellular space.
How does collagen assembly begin?
Begins with disulphides bond formation between C-terminal extensions - facilitates triple helix assembly.
