Constitutive expression of erythromycin resistance mediated by the ermAM determinant of plasmid pAM beta 1 results from deletion of 5' leader peptide sequences

Plasmid. 1987 Nov;18(3):250-3. doi: 10.1016/0147-619x(87)90068-0.


We have sequenced the erythromycin resistance determinant (erm) of the Streptococcus faecalis plasmid pAM beta 1 to investigate its relationship to other known resistance determinants. We show that this determinant is strongly (99%) homologous at the DNA level to that of plasmid pAM77 (Streptococcus sanguis) and of transposon Tn917 (S. faecalis). Moreover, nucleotide sequence comparison with the determinants of pAM77 and Tn917 shows that most of the probable regulatory region is absent, providing an explanation for the constitutive expression of the pAM beta 1 erm determinant.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Chromosome Deletion*
  • Drug Resistance, Microbial / genetics*
  • Enterococcus faecalis / genetics
  • Erythromycin / pharmacology*
  • Gene Expression Regulation*
  • Molecular Sequence Data
  • Plasmids*
  • Protein Sorting Signals*


  • Protein Sorting Signals
  • Erythromycin

Associated data

  • GENBANK/M20334
  • GENBANK/M20335