Update README.md

README.md

 This repository contains the code used in the paper:
 
 ***Genome-wide CRISPR-dCas9 screens in E. coli identify essential genes and phage host factors***,
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 François Rousset, Lun Cui, Elise Siouve, Florence Depardieu & David Bikard (2018)
 
 In this study we use a library of guide RNAs targeting random positions