Tetracycline resistance is common among isolates of the animal commensal and opportunistic pathogen Arcanobacterium pyogenes. The tetracycline resistance determinant cloned from two bovine isolates of A. pyogenes was highly similar at the DNA level (92% identity) to the tet(W) gene, encoding a ribosomal protection tetracycline resistance protein, from the rumen bacterium Butyrivibrio fibrisolve...

A genetic basis for tetracycline resistance in cutaneous propionibacteria was suggested by comparing the nucleotide sequences of the 16S rRNA genes from 16 susceptible and 21 resistant clinical isolates and 6 laboratory-selected tetracycline-resistant mutants of a susceptible strain. Fifteen clinical isolates resistant to tetracycline were found to have cytosine instead of guanine at a position...

OBJECTIVES To identify the genes responsible for tetracycline resistance in a strain of Streptococcus australis isolated from pooled saliva from healthy volunteers in France. S. australis is a viridans Streptococcus, originally isolated from the oral cavity of children in Australia, and subsequently reported in the lungs of cystic fibrosis patients and as a cause of invasive disease in an elder...

In the present study, the tetracycline-off and Cre/loxP systems were combined to gain temporal and spatial control of transgene expression. Mice were generated that carried three transgenes: Tie2-tTA, tet-O-Cre and either the ZEG or ZAP reporter. Tie2-tTA directs expression of tetracycline-controlled transactivator (tTA) in endothelial and hematopoietic cells under the control of the Tie2 promo...

The tetracycline repressor/operator system was adapted for use in Leishmania donovani. In order to investigate the possible importance and function of open reading frame F (ORFF) in Leishmania donovani strain AG83 that has a single copy of ORFF in the LD1 locus on chromosome 35, we have attempted to generate tetracycline regulatable single allele mutants of ORFF. Leishmania cells expressing the...

INTRODUCTION Scarce data are available on Group A Streptococcus (GAS) antibiotic resistance in South America. METHODOLOGY The antibiotic susceptibility patterns of GAS recovered from symptomatic children living in the central part of Brazil during a prospective epidemiological study were analyzed. RESULTS No isolates were resistant to penicillin or macrolides.  Sixty-one percent of the isol...

A plasmid determining tetracycline resistance was demonstrated for Staphylococcus epidermidis. Tetracycline resistance was spontaneously lost from a S. epidermidis strain at a frequency of <0.1 to 1.3%. Frequency of loss was not appreciably enhanced by growth at 42 C or in ethyl violet. The rate of transduction of tetracycline resistance in three S. epidermidis crosses was decreased as a functi...

A study was conducted to understand the descriptive and molecular epidemiology of antimicrobial-resistant gram-negative enteric bacteria in the feces of healthy lactating dairy cattle. Gram-negative enteric bacteria resistant to ampicillin, florfenicol, spectinomycin, and tetracycline were isolated from the feces of 35, 8, 5, and 42% of 213 lactating cattle on 74, 39, 9, 26, and 82% of 23 farms...