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1. You are planning to study a gene ydeH from E.coli that encode for putative di

ID: 99782 • Letter: 1

Question

1. You are planning to study a gene ydeH from E.coli that encode for putative diguanylate cyclase activity (synthesis of a second messanger c-di-GMP). The in vitro enzymatic assay requires incubation of protein with GTP. List the steps involve in purification of protein. (hint : you need to clone the gene, express and purify the protein for in vitro assays.)

1a. Find the sequence of gene: Using NCBI or other database

2b. Design a strategy to clone and express the gene

- How will you clone the gene using PCR.?

- Design primers (sequence)

- Clone it in a plasmid (you can choose a plasmid from pET21b, pET28a, pUC19, pBAD24

- how will you select and screen the colonies?

- how will you express the protein?

- how will the protein be purified?

Explanation / Answer

2b. A strategy to clone and express the gene is as follows: