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Because the liquid film that lines the alveolus resembles a…

Because the liquid film that lines the alveolus resembles a bubble or sphere, according to ___________ law, when the alveolar fluid is permitted to behave according to its natural tendency, a __________    ______________ pressure must be generated to keep the small alveoli open.

You have joined the Wee lab as an undergraduate student. Thi…

You have joined the Wee lab as an undergraduate student. This lab’s expertise is in protein engineering. You are tasked with purifying proteins for the research group.  The protein is a DNA polymerase (which binds negatively charged DNA) from a thermophilic organism (Pseudomonas furiosis). Your colleague has cloned this gene in the bacteria E. coli. Because the enzyme’s activity is negatively impacted by the addition of affinity tags, no tag was added to the gene recombinantly expressed.  Your goal is to purify this protein to a high degree of purify (>95%). But, you are challenged to purify your assigned protein in no more than two steps.  In your lab, you have access to the following chromatography techniques and columns.  Cation exchange chromatography Anion exchange chromatography Protein A chromatography Immobilized metal affinity chromatography Amylose resin Sepharose B resin Hydrophobic interaction chromatography Size exclusion chromatography Heat treatment Ammonium sulfate precipitation Your response to this question may take the following format.  For step 1, I will choose method X. Method X separates between based on property A. I chose method X because ….. For step 2, I will choose method Y Method Y separates proteins based on property B. I chose method Y because….  If you used a chromatography column in steps 1 and/or 2, you must specify how you will operate the column to retrieve (elute) your protein (increasing or decreasing salt gradient, pH adjustment, molecule addition).