Ayoung investigator would like to express and purify a newly discovered gene. she decides to clone the gene into a plasmid that contains the sequence for a hexahistidine tag. plasmids that contain a sequence encoding a hexahistidine tag will produce a recombinant protein with an additional six histidine residues attached to the n (or c ) terminus. her gene of interest will be expressed as an n ‑terminal fusion protein containing the six residue histidine tag (n−his6−protein−c) . order the steps for construction of the expression plasm