Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
17 Cards in this Set
- Front
- Back
|
Collagen is made up of? |
3 alpha polypeptide chains |
|
|
Collagen type 1 contains what chains? |
2 (alpha1 chains) 1 (alpha 2 chain)collagen type 2 |
|
|
Collagen type 2 has what chains? |
3 (alpha1 chains) |
|
|
Type 1 collagen found in? |
Bones Tendons Blood vessels Cornea of eye |
|
|
Type 2 collagen is found in ? |
Cartilage |
|
|
Type 3 collagen is found in? |
Skin and blood vessels |
|
|
Gly-X-Y
What amino acids frequently occupies the X position and Y position in collagen peptide chains? |
X = Proline Y = 1. hydroxyproline 2. Hydroxylysine |
|
|
Hydroxyproline's contribution to collagens tensile strength? |
Forms hydrogen bonds between collagen alpha chains to stabilize triple helical structure |
|
|
Hydroxyl group of Hydroxylysine is involved in? |
Enzymatic glycosylation of collagen |
|
|
What co factor is needed for enzymatic hydroxylation of proline and lysine to form Hydroxylysine and hydroxyproline |
Vitamin C (Asorbic acid) Fe++ O2 |
|
|
Where in the cell does the pro alpha chain undergo hydroxylation? |
RER Rough endoplasmic reticulum |
|
|
The cleavage of pro-collagen N terminus and C terminus ends by procollagen peptidases occurs...................... And releases....................... |
1.In the extra cellular space 2. Triple helical tropocollagen |
|
|
Cross linking of individual collagen fibrils yields mature collagen fibers. How is this cross linking derived? |
Deamination of lysine and Hydroxylysine by copper containing enzyme Lysyl Oxidase to form reactive aldehydes Allysine & Hydroxallysine These form covalent bonds with lysine and hydroxy lysine of another collagen fibril. |
|
|
Ehlers-Danlos Syndrome causes and types? |
Deficiency in enzymes Lysyl hydroxylase & procollagen peptidases.
Mutation in A.A sequence of collagen type 1,2,3
Classic EDS = Collagen type V defect.
Vascular EDS = Defect in collagen type 3 |
|
|
Osteogenesis Imperfecta causes and types? |
Defect in collagen type 1 (mutation where Glycine is replaced by a bulky A.A in the collagen alpha chain)
Type1 = most common (mild bone fragility, hearing loss, blue sclera)
Type2 = in utero fractures seen in fetus.
Type3 = severe. Multiple fractures at birth, kyphosis, blue sclera, short stature. |
|
|
Children with osteogenesis Imperfecta can be treated with? |
Bisphosphonates (Inhibits osteoclastic activity) |
|
|
Elastin's properties are? |
Elastic in nature and insoluble |
