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For affinity purification of a protein from a bacterial lysate, which of the following collections would you expect to see the highest concentration of your desired (tagged) protein?

You are picking reagents for a 5-color flow cytometry experiment. Without considering the expression level of the targets in the experiment or the brightness of the fluorochromes, only based on the distribution of the colors which combination of fluorophores would you pick?   A B

You have stained cells for a flow cytometry experiment with an anti CD62L -APC antibody. Plotting the APC fluorescence you observe 3 populations. If the blue line represents an unstained control sample, what description of the populations labeled 1, 2 and 3 would be appropriate?    

Which tag is commonly used for affinity purification with immobilized metal columns?

You recorded a flow cytometry experiment with a sample that had several cell populations in it. Plotting FSC vs. SSC which population (labeled in the graph as 1, 2 or 3) in this graph are the largest?  

What factors should you consider when deciding which expression system (bacteria, yeast, mammalian cell) to use to express your group’s protein include:

You recorded a flow cytometry experiment with two markers (CD19 and CD3) and plotted on a bi-variate plot. X axis represents CD19 expression, on the Y axis CD3 expression. How would you describe the populations that are labeled in the corners as Q1, Q2, Q3 or Q4?  

Which host cell feature makes BL21(DE3) E. coli strains preferred for recombinant protein expression?

Which region of an antibody is responsible for antigen binding?

What is the main difference between an affinity tag and an epitope tag?