Filamentous phages as cloning vectors.

The virtue of Ff vectors goes beyond the fact that they deliver a single strand in a convenient package for sequencing and oligonucleotide-directed mutagenesis. Of all vectors in common use they are the easiest to propagate and process. Their genomes can be easily manipulated, and the knowledge acquired over a quarter century of basic research makes their behavior reasonably predictable. For this reason I have emphasized the general properties of Ff phage in this review and dealt at some length with applications that are still not fully developed, I hope this review will inspire readers to continue the tradition of imaginative exploitation of this unique class of viruses.