You analyze a protein and obtain the results shown below. What is TRUE about this gel?

Peak 3 below from an ion exchange column shows

A protein is acetylated at lysine 255 (K). Researchers mutated the protein in the western blot of an SDS-PAGE below. What can you conclude from this figure?

Which of the following is FALSE regarding purifying proteins using the ammonium sulfate precipitation?

You wish to express a protein expression system that is very fast, inexpensive, and has established protocols that have been perfected over the past few decades, rather than explore a newer system. Which expression system would you choose?

Why are proteins stored in a buffer with dithiothreitol or β-mercaptoethanol?

You purify a protein with an anion exchange chromatography and elute it with 1 M NaCl. You take this eluate and load it directly onto a cation exchange column, but the protein was found only in the flowthrough and not the elution. What was the cause of this?

A pregnancy test is equivalent to which of the following techniques?

You are working with a protein that is polyubiquitinated (a variable number of ubiquitins), which you visualize with an anti-ubiquitin antibody. You treat the protein with an enzyme that cleaves ubiquitin from proteins and degrades it (+ lane). What would be the expected results?

A blue native PAGE is advantageous over a standard native gel because it