FIG. 1.
Construction of libraries. The arrows flanking the BamHI cloning site, denoted p1-pN for the library in pTCV-hly and p2-pN for the library in pAT28-hly, correspond to the pairs of primers used to amplify and sequence the chromosomal DNA fragments inserted upstream of hly. The BamHI and SalI sites flanking the hly gene are underlined.