pEMBL: a new family of single stranded plasmids

TLDR

pEMBL plasmids become encapsidated as single‑stranded DNA when superinfected with phage F1. The authors engineered the pEMBL family by inserting a bla selectable marker, an alpha‑peptide coding segment with a multiple‑cloning polylinker, and the phage F1 intragenic region into a plasmid backbone. These vectors have been successfully employed for dideoxy sequencing, offer the same versatility as M13 derivatives, but are smaller, easier to purify, and provide greater stability for long inserts.

Abstract

We have constructed a series of plasmids, the pEMBL family, characterized by the presence of 1) the bla gene as selectable marker, 2) a short segment coding for the alpha-peptide of beta-galactosidase and containing a multiple cloning sites polylinker, 3) the intragenic region of phage F1. pEMBL plasmids have the property of being encapsidated as single stranded DNA, upon superinfection with phage F1. These vectors have been used successfully for DNA sequencing with the dideoxy-method, and can be used for any other purpose for which M13 derivatives are used. However, the pEMBL plasmids have the advantage of being smaller than M13 vectors, and the purification of the DNA is simpler. In addition, and most importantly, long inserts have a higher stability in pEMBL plasmids than M13 vectors.