Restriction digests of the clone give the following sizes (kb): EcoRI--33.5, 14.5; BamHI--33.5, 14.5. By labeling the left cohesive end, which is 200 bp from cloning sites, reliable restriction maps of clones can be made from partial digests. For library construction, a double digest of the vector with BamHI + EcoRI and removal of the linker fragment reduces the number of background phage. Phosphatase treatment of digested vector eliminates background. A modified EMBL vector, with all phage coding sequences to the right of the cloning sites to facilitate restriction mapping of clones. Can be used for genomic library construction. |