Nucleotide sequence analysis of tetracycline resistance gene tetO from Streptococcus mutans DL5

Abstract

Streptcoccus mutans DL5, isolted from the dental plaque of a pig, was resstant to high levels of streptomycin (Sm, 20 mg/ml), erthromycin (Em, 1 mg/ml), and tetracydine (Tc, >100 pg/ml), but ontaine no detectable plasndd DNA. The Smr and Emr determinants were doned from celluar DNA on the self-replicating 5- Lett. 4:153-160, 1987). A 1.67kbp NdeI ftgment, internal to the ORF from strain DLS, as well as pDL421 hybridized under sngent co ns to DNA from 10 of 10 Tcr strains of C. coli and Canpylobacter jejuni from human and animal sources, but not to DNA from Tce isdates of these two species.Bacterial tetracycline resistance (Tc7) is encoded by a diversity of genetic determinants. Levy and associates (15,21)

A DNA sequence upstream of the tet(O) gene is required for full expression of tetracycline resistance

“…(18,20), Streptococcus mutans (9), and Enterococcus faecium (1). The determinant has been cloned and expressed in Escherichia coli (9,18,20). The deduced amino acid sequence of Tet(O) is very similar to that of Tet(M) (76% identity [13]), which has been found in a wide variety of gram-positive and gram-negative bacteria (21).…”

“…The sequences of several tet(O) and tet(M) genes have been determined (3,9,11,13,14,16,18); however, little is known about the resistance mechanism or the control of expression of these genes. We believe that genetic studies of both tet(O) and tet(M) are necessary to understand the biochemical basis of Tet(O) and Tet(M) action as well as the reason for the ability of these resistance determinants to be expressed in a wide variety of bacteria.…”

“…(18,20), Streptococcus mutans (9), and Enterococcus faecium (1). The determinant has been cloned and expressed in Escherichia coli (9,18,20).…”

“…The determinant has been cloned and expressed in Escherichia coli (9,18,20). The deduced amino acid sequence of Tet(O) is very similar to that of Tet(M) (76% identity [13]), which has been found in a wide variety of gram-positive and gram-negative bacteria (21).The sequences of several tet(O) and tet(M) genes have been determined (3,9,11,13,14,16,18); however, little is known about the resistance mechanism or the control of expression of these genes. We believe that genetic studies of both tet(O) and tet(M) are necessary to understand the biochemical basis of Tet(O) and Tet(M) action as well as the reason for the ability of these resistance determinants to be expressed in a wide variety of bacteria.…”

Sequencing of a tet(Q) gene isolated from Bacteroides fragilis 1126

“…Three classes of ribosome protection mechanisms have been reported: Tet M, Tet 0, and Tet Q. Tet M represents the most widespread tetracycline determinant, as it has been isolated from a wide range of grampositive, as well as gram-negative, bacteria (2,3,5,7,8,18,22,(29)(30)(31). The Tet 0 determinant found in streptococci (21) and campylobacters (25) codes for resistance to all tetracycline antibiotics, including minocycline. Only one gene of the newly reported ribosomal protection determinant Tet Q has been described.…”