title: The aminoglycoside-resistance operon of the plasmid pSa: nucleotide sequence of the streptomycin-spectinomycin resistance gene.
abstract: The nucleotide sequence of the probable C terminus of the kanamycin-resistance gene (KmR) and the probable complete sequence of the streptomycin-spectinomycin-resistance gene (SpR) of the IncW plasmid pSa have been determined. The two genes appear to be oriented in the same direction and separated by a spacer region of 53 bp, with transcription proceeding from the KmR gene into the SpR gene. An RNA transcript encompassing the C terminus of the KmR gene, the 53-base spacer, and the N terminus of the SpR gene has the potential to form a stem-loop structure with a free energy value of -68 kcal/mol. The SpR gene of pSa has extensive sequence homology with the aadA gene of the plasmid R538-1. Comparison of the proposed amino acid sequence of the KmR protein of pSa with those of two aminoglycoside phosphotransferases revealed a region of potential homology with those proteins.
mesh_terms: D001483:Base Sequence; D004262:DNA Restriction Enzymes; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000235:genetics*; D005798:Genes, Bacterial; D007612:Kanamycin / Q000494:pharmacology*; D009690:Nucleic Acid Conformation; D009876:Operon; D011815:R Factors; D000198:Spectinomycin / Q000494:pharmacology*; D013307:Streptomycin / Q000494:pharmacology*
chemical_list: D007612:Kanamycin; D000198:Spectinomycin; D012321:DNA-Directed RNA Polymerases; D004262:DNA Restriction Enzymes; D013307:Streptomycin