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Fibrous Protein Examples:

Fibrous Protein Examples:. a -Keratins: hair, nails, skin - a -helical structure of chains. b -Keratins: feathers, scales ... - b -sheet structure of chains. Fibroin: silkworms, spider silk - b -sheet structure of chains. Collagen: ~ 1/3 of animal protein

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Fibrous Protein Examples:

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  1. Fibrous Protein Examples: a-Keratins: hair, nails, skin - a-helical structure of chains b-Keratins: feathers, scales ... - b-sheet structure of chains Fibroin: silkworms, spider silk - b-sheet structure of chains Collagen: ~1/3 of animal protein skin, bones, connective tissue, teeth, gums .... etc

  2. insoluble cross-linked Structures water soluble folded multi-tasked Fibrous vs. Globular Proteins

  3. Amino Acids & Nutrition RDI = 60 g Essential   absent in gelatin .... - Gly - xxx - Pro -... GPRGPAGPPGRDGIPGQPGLPGPPGPPGPPGPPGLGGNF

  4. Collagen Triple Helix

  5. N Ca C O CH2 CH2 CH OH Proline (Pro) Hydroxyproline (Hyp) 2 Prolyl Hydroxylase

  6. ProlineHydroxylase - lumen of ER - Fe and ascorbic acid PH(Fe2+)+ O2 + a-ketoglutarate + Xaa-Pro-Gly PH catalyzes hydroxyproline formation PH(Fe2+)+ succinate + Xaa-Hyp-Gly Also …. PH(Fe 2+)+ O2 + a-ketoglutarate succinate + … PH(Fe3+)(not functional until reduced back to Fe2+) + Vit. C (red) PH(Fe2+)+ vit. C (ox)

  7. Collagen Sequence Gly-Pro-Met-Gly-Pro-Ser-Gly-Pro-Arg- Gly-Leu-Hyp-Gly-Pro-Hyp-Gly-Ala-Hyp- Gly-Pro-Gln-Gly-Phe-Gln-Gly-Pro-Hyp- Gly-Glu-Hyp-Gly-Glu-Hyp-Gly-Ala-Ser---- Hyp CH2 - CH2 - CH - OH

  8. CH2 H O - CH - CH2 | CH2 - CH2 - CH - OH H-bonds cross-link collagen chains

  9. Scurvey : Disease associated with Vitamin C deficiency ...caused by weakness in connective tissue ... caused by failure to form sufficient cross-links in collagen ... caused by insufficentvitamin C for ProlineHydroxylase (Fe3+) reduction Should you make sure your pet dog gets enough vitamin C? a) yes b) no Vitamin C is synthesized metabolically in all animals except …. humans, bats, guinea pigs, monkeys/apes (some fish/birds?)

  10. OsteogenesisImperfecta Disease of? A) muscle b) nerves c) blood d) bones In what movie did Samuel L. Jackson have OI? Four types with varying severity ― I, II, III, IV Cause: mutation in gene for procollagena-1 chain Effect: interfere with 3-helix formation collagen used to make bone is weaker Procollagena-1 chain: mutations Gly221 Cys OI mild form Gly389 Cys OI moderate form Gly425 Ser OI lethal form Why do you think mutations of Glycine are causes of OI? a) Gly is small b) Gly forms H-bonds c) Gly is nonpolar

  11. http://www.youtube.com/watch?v=aopdD9Cu-So

  12. Soluble Collagen Disease SColD

  13. $$ $$ Save The Witches Fund c/o Paul Stein Department of Chemistry The College of St. Scholastica

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