ESTABLISHMENT OF A GENOMIC BANK OF BOVINE HERPESVIRUS-1 USING A NOVEL POSITIVE SELECTION PLASMID VECTOR

A small positive selection cloning vector, designated pSiig1, suitable for the construction of genomic banks in E. coli is described and used for the establishment of a bank of the bovine herpesvirus 1 genome. Hybrid transformants are directly selected on agar plates containing ampicillin. The vector is based on the replicon of R1 and has a lambda P(R) promotor inserted upstream of the replication control genes. The vector has an uncontrolled (runaway) replication and is lethal to the host cell unless the P(R) promotor is brought under trans-acting control of the lambda cI repressor or runaway replication is blocked by an insertion between the P(R) promotor and the replicon. The vector contains a unique Bg/II site between P(R) and the replicon which is suitable for insertion of genomic DNA.