Biochem test 2 objectives - Chapter 4-7

Biochem test 2 objectives - Chapter 4-7 - Biochem Exam 2...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
Biochem Exam 2 Objectives Chapter 4 Objectives (7-11) 7. Define native protein, denature protein, renatured protein; list conditions under which globular proteins may be denatured and renatured, using ribonuclease as a model; describe molecular chaperones and protein disulfide isomerases and their roles in protein folding; discuss the protein folding process, diving it into early, intermediate, and final stages. Native conformation is the biologically active conformation of a macromolecule, such as a protein. A denatured protein has lost its native conformation by exposure to a destabilizing agent. Destabilizing agents include heat, pH extremes, organic solvents, high concentrations of salts, detergents, and H- bond breaking reagents such as urea. Renaturation is the refolding of a denatured protein to restore native structure and functional activity.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Early events - local secondary structures (αα, αβ, ββ) formed - hydrophobic collapse with expulsion of water Intermediate stage - secondary structure stabilized - domains created by motif combination Final steps - compaction of domains into a core Molecular chaperones are specialized proteins which facilitate correct folding for proteins which do not fold spontaneously.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
There are two classes of molecular chaperones. Hsp70 is a class of MW~70,000 (heat shock proteins) which protect proteins denatured by heat, or those still unfolded. Chaperonins are elaborate protein complexes required for folding of cellular proteins which do not fold spontaneously; GroEl and GroES are the best studied of these chaperonins. These folding accessory proteins aid in exchange reactions. Intermediate stage disulfide bonds may not be in the proper place for final folding. Isomerases catalyze formation and exchanges of bonds between cysteines now closer in the final conformation. 8. Briefly outline the use of X-ray crystallography in determination of protein structure. 9. Review the general structures of myoglobin (Mb) and hemoglobin (Hb); sketch or recognize their their oxygen saturation plots at pH 7.4, as well as at pH 7.2 and 7.6; note the role of 2,3- bisphosphoglycerate (BPG) in oxygen affinity of Hb. ****Review the general structures of myoglobin and hemoglobin
Background image of page 4
10. Discuss prions and prion diseases-mad cow (BSE) and variant Creutzfeldt-Jakob disease in humans.
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
11. Discuss mutant hemoglobin; compare Hb A and S and distinguish sickle-cell trait and sickle cell disease.
Background image of page 6
In the human population, more than 300 genetic variants of Hb occur.
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 8
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 05/01/2011 for the course CHEMISTRY 410 taught by Professor Bayse during the Spring '11 term at Spelman.

Page1 / 16

Biochem test 2 objectives - Chapter 4-7 - Biochem Exam 2...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online