Biochem 80 Flashcards
Which 4 steps of collagen synthesis occur inside fibroblasts
1) Synthesis (RER)
2) Hydroxylation (RER)
3) Glycosylation (RER)
4) Exocytosis
Which 2 steps of collagen synthesis occur outside fibroblasts?
1) Proteolytic processing
2) Crosslinking
Which amino acids are found in Collagen?
1) Glycine (most abundant)
2) Lysine
3) Proline
Which residues become hydroxylated in collagen sythesis?
Lysine and Proline
A defect in hydroxylation in collagen synthesis can lead to what?
Scurvey due to Vitamin C deficiency (Vit. C is required for cross linking)
Which residues become glycosylated?
Pro alpha chain hydroxylysine
Which bonds make up procollagen during the glycosylation step?
Hydrogen and Disulfide bonds
Problems forming the triple helix in glycosylation lead to what disease?
Osteogenesis Imperfecta
What occurs during the proteolytic processing phase of Collagen synthesis?
Cleavage of disulfide rich terminal regions of procollagen
Which molecules are cross linked in the Cross linking phase?
Lysine-hydroxylysine (covalent)
What enzyme cross links fibers in collagen synthesis? What does it contain?
Cu containing Lysyl Oxidase
Problems with cross linking lead to what disorder?
Ehlers - Danlos
Dental imperfections in O.I. are due to lack of what?
Dentin
Blue sclera in O.I is due to what?
The translucency of the connective tissue over the choroidal veins
Glycosylation occurs with what sugars?
Glucose and Galactose
UW: 1246
