Exam 3: Protein Structure and Function

GTPases serve in many signal transduction pathways and the presence of GTP or GDP dictates whether the pathway is on or off,respectively.Which of the following statements is true regarding guanine nucleotide exchange factors (GEF)and their role in these signaling pathways?

The Km for an enzyme-catalyzed reaction:

Protein self-splicing:

The conversion of inactive chymotrypsinogen to active chymotrypsin is an example of:

Proteases that attack selected peptide bonds within a polypeptide chain are synthesized and secreted as inactive forms called:

Describe the general mechanism by which a multisubunit protein can be activated by binding an allosteric effector molecule.

Two proteins that have a similar function:

All the following statements about molecular chaperones are true EXCEPT:

Mass spectrometry techniques are used in proteomics for all of the following purposes EXCEPT:

What types of bonds are apt to be more common in the nonaqueous,interior environment of a protein than in the aqueous,surface environment of a protein?

How can gel filtration chromatography separate proteins based on their mass?

What role does aberrant protein folding play in the development of a disease such as Alzheimer's disease?

Eggs are protein-rich foods.An uncooked egg can catalyze a reaction that breaks down bacterial cell walls.After cooking,this activity is almost abolished.This is likely because:

In two-dimensional gel electrophoresis,proteins are first resolved by _____ and then by _____.

What is positive cooperativity?

You disrupt all hydrogen bonds in a protein.What level of structure will be preserved?

A small molecule that binds directly to the active site of an enzyme and disrupts its catalytic reaction is called:

Describe the types of bonds/interactions that hold together or stabilize the primary,secondary,tertiary,and quaternary structures of proteins.

Modification of proteins by ubiquitin and ubiquitin-like E3 ligases can stimulate all of the following EXCEPT:

Hsp90 family members are present in all organisms except: