First time making a genomic library

[Awol]

I am a molecular biology student and I have been making genomic libraries in E.coli for the first time. I was posed a question by my prof. that has confused me.

I am asked whether this approach, using two different restriction enzymes, could be used to generate a complete genomic library? And if not why not. It is perhaps the definition of 'complete genomic library' that puzzles me, I would be grateful if someone could shine some light on this for me.

We are using the plasmid pUC19 with restriction enzymes EcoRI and BamHI.

[Cat]

Possibly yes. But how would you know if it's complete? That I see as a problem.

[JackBean]

You should get complete library (if you use sufficient number of clones) with any REs. There is a calculation to get number of clones which you have to screen to get your gene of interest with some probability.

The only thing which might be of concern could be telomeric ends of chromosomes and if these two REs cut too far appart. I'm not sure, what is the limit for the inserts, but it might happen, that they cut too far appart and thus such piece could not be used.