Shown below is a binding curve for a drug binding to a single binding site on a target protein.

Using information from this curve, estimate the concentration of the drug required such that 90% of the protein molecules will be bound to the drug.

Your answer should be given in units of nanomolar (nM).

Type only numbers (do not type the units or any other additional characters)

Hint: if you're struggling here because the graph doesn't go high enough, think about what information you can glean from the graph and take it from there.

Shown below are the binding curves for wild type and mutant forms of myoglobin.

Which of the following can best explain the effect of the mutation on oxygen binding by myoglobin?

Shown below (left) is a hydropathy plot for a polytopic integral membrane protein.

Also shown (right) are four topology diagrams (A-D) for integral membrane proteins.

Red arrows indicate the positions at which lysine residues are readily labelled with a chemical reagent added to the extracellular medium.

Which topology diagram is most consistent with the hydropathy plot and lysine labelling pattern shown?

Shown below is a Lineweaver-Burk (double-reciprocal) plot for an enzyme-catalysed reaction.

What is the Km value for this reaction? 

(Type your answer in units of mM but do not type the units or any other characters except the number itself.)

Shown below is a Michaelis-Menten kinetics curve for a reaction carried out using an enzyme concentration of 1 nM (0.001 μM).

What is the k_cat value for this enzyme-catalysed reaction?

Type your answer as a number in units of min^-1 but do not type the units or any other characters except the number itself.

The following sequence forms an amphipathic α-helix:

Ala-Val-Asn-Asp-Glu-Ile-Ser-Thr-Leu-Met-His-Arg-Val-Lys-Ser-Phe-Phe-Gly

In your mind (or by taking a photo, sketching it out, annotating on the screen, or doing-whatever-you-need-to-do-because-this-isn't-a-paper-exam-so-I'm-adapting-it-here-for-this-revision-quiz...), map the sequence onto the helical wheel shown below. The position of Ala-1 is already shown.

Which side of the helical wheel diagram represents the hydrophobic side of the helix?

Shown below is a ribbon representation of the enzyme triosephosphate isomerase.

True or False, The region labelled "J" is the C-terminus.

Isoelectic focussing is an old but nevertheless useful technique of separating proteins along a gel strip containing an immobilised pH gradient.

In an experiment utilising this technique, a mixture of four proteins (with known pI values of: 9.3, 8.1, 6.5, and 4) was added to the gel strip and an electric field applied. Then, the gel was stained so that proteins could be visualised.

From the image below (where black ovals represent the stained and visualised proteins), which gel strip represents the one corresponding to the above mixture of proteins?

A researcher studying enzyme kinetics created the following series of Michaelis-Menten ("MM") and Lineweaver-Burk ("LB") plots, shown below, but forgot which MM plot went with which LB plot.

Can you help them out and correctly pair up the graphs?

Hi, I'm a tRNA and my anti-codon is 5'-CAA-3'

What amino acid do I LOVE to bring into the ribosome?