Identification of deoxyribonucleic acid restriction fragments of beta-converting corynebacteriophages that carry the gene for diphtheria toxin

Abstract

DNA fragments bearing the gene for diphtheria toxin were identified in restriction enzyme digests of DNA from .beta.-converting and .gamma.-nonconverting corynebacteriophages [in Corynebacterium diphtheriae]. A combination of physical and genetic evidence has established that the BamHI band C fragment of .beta. phage DNA which carries the specific phage attachment site also carries most and probably all of the gene for diphtheria toxin. A detailed restriction map of this tox-bearing BamHI fragment was developed, and the locations and orientation of the tox gene and the attP site within this fragment were established.