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The process of learning to get along with others is called .

The fear of being away from familiar people and places is known as anxiety.

(4 pts) Which would you expect to be higher, the RWork or RFree of a crystal structure? Why? 

(2 pts) Where on the below diffraction image would you expect to find the reflections that correspond to the highest resolution data? 

(12 pts) The chemical shift is one of the most important experimental NMR parameters which becomes readily available at a very early stage of a protein NMR study. Amino acid chemical shifts are determined by the corresponding covalent structure (identity of amino acid; e.g. Gly vs. Ala or atom in an aromatic sidechain vs. atom in an aliphatic sidechain), the neighboring amino acids (flanking in the primary sequence), interactions with other amino acids through space (e.g. spatial vicinity in a folded protein). Shown below are the “fingerprint” 2D 1H-15N HSQC spectra of a protein acquired under two conditions (A and B).     a) The resonances of which exactly atoms are correlated in a 2D 1H-15N HSQC experiment? (4 pts)   b) Which of the two conditions (A and B) corresponds to non-native conditions (9M urea) and which to native conditions (0M urea)? Justify your answer (8 pts) 

(8 pts total) After preparing a cryo-EM grid, what are the major steps (between 6 and 8 steps discussed in class) of collecting and processing cryo-EM data (6 pts)? Name two common problems that could arise in this workflow and provide a strategy to address each (2 pts).

(4 pts) Would you expect to see more detail in a crystal structure that has a resolution of 1 Angstrom or 3 Angstrom? Why? 

(8 pts total) Describe two reasons why cryo-EM structures may be more physiologically relevant than crystal structures (4 pts). Then, describe two technical advantages of cryo-EM over crystallography (4 pts).

(4 pts) Which of the methods from the above question would be most appropriate to use when you know the structure of a closely related protein? Also, what does the abbreviation for this method stand for? 

23F is following up with the neurology clinic after her hospitalization for IVH into the temporal space. She is being switched to phenytoin for her AED. She asks why she was started on levetiracetam inpatient if the ultimate plan was to transition to phenytoin. The RN’s best explanation is: