Characterization of a Small Plasmid Determining Resistance to Erythromycin, Lincomycin, and Vernamycin B α in a Strain of Streptococcus sanguis Isolated from Dental Plaque

Abstract
A plasmid determining resistance to erythromycin (inducible), lincomycin and vernamycin B.alpha. was isolated from a strain of S. sanguis isolated from dental plaque of a patient who was on erythromycin therapy for an extended period of time. The plasmid, designated pAM77, had a MW of 4.5 .times. 106 and was present to the extent of 1-2 copes/bacterial chromosome. The plasmid could transform S. sanguis strain Challis.