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Please answer the following questions and mark all of the answers that apply (th

ID: 48752 • Letter: P

Question

Please answer the following questions and mark all of the answers that apply (there may be more than one answer). Thank you!!

After samples are ionized, an electric field is applied In order to deflect charged particles. Which of the following predicts the magnitude of deflection of each sample?

[ ] Mass/charge of sample

[ ] Kinetic torque of sample

[ ] Shape of sample

[ ] None of the above

When using mass spectrometry to sequence short stretches of polypeptide, why can’t it sequence the difference between leucine and isoleucine?

[ ] Because leucine and isoleucine have the exact same mass and charge.

[ ] Because both of the amino acids have the exact same polarity, which leads to this ambiguity.

[ ] Because due to the hydrophobic nature of the leucine and isoleucine leads it to absorb the electrospray (which is an oil)—and thus cannot be forced into a gas phase.

[ ] Because the charge difference between the two is too small to be distinguishable by the spectrometer.

Inhibitors that bind to the same site as the substrate are called ______________ inhibitors:

[ ] Mixed

[ ] Uncompetitive

[ ] Allosteric

[ ] Competitive

An inhibitor that forms a covalent bond with the –SH groups of Cys residues in a protein is most likely a(n) ____________ inhibitor.

[ ] Irreversible

[ ] Competitive

[ ] Non-competitive

[ ] Reversible

Mark all that apply. Which parameter(s) of the Michaelis-Menten equation relate(s) to the affinity of an enzyme for its substrate?

[ ] Km

[ ] Vmax

[ ] V0

[ ] Slope of the line

Explanation / Answer

1. Mass/charge of sample

2. Because leucine and isoleucine have the exact same mass and charge.

mass spectometry identifies the aminoacids on the basis of mass and charge

3.Competitive

in competitive inhibition, binding of the inhibitor to the active site of the enzyme prevents the substrates to bind and the vice versa

4.Non-competitive

5.Km. Km measure the affinity of an enzyme. small value of Km indicate high affinity.