We have mutagenized a clinical strain of Salmonella enterica sv. typhi with mini-transposon Tn10dTet (T-POP) to obtain conditional lethal (tetracycline-dependent) mutants with T-POP insertions upstream of essential genes. Generalized transducing phage P22 was used to introduce T-POP from a S. typhimurium donor into a S. typhi recipient. Chromosomal DNA was purified from the mutagenized donor st...

Tetracycline administered in low doses can be effective in the long-term management of patients with meibomian keratoconjunctivitis (MKC). However, the mechanism of action does not appear to be a reduction of bacteria. Seventy-five percent of the ocular staphylococci in such patients are resistant to tetracycline. An alternative mechanism of action could be the inhibition of production of extra...

Objective(s): The aim of the present study was to determine the aminoglycoside modifying enzymes (AMEs) encoded genes, tetracycline resistance genes, and the coa based typing of Staphylococcus aureus isolates in the Southwest of Iran. Materials and Methods: Antimicrobial susceptibility of isolates was carried out by agar disk diffusion methods. Two sets of multiplex PCR mixture were used for de...

The frequency of carriage of antibiotic-resistant bacteria in healthy 7- and 8-year-old children in Bristol was studied. Children born in Avon between 1 April 1991 and 31 December 1992, attending the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC) 7 year follow-up clinic, formed the study population. Carriage was estimated using mouth and stool samples. None of 105 children on whom ...

background: multidrug resistant enterobacteriaceae which was confined to the hospital environments is now emerging in the domestic food related environments as well. the main objective of the present study was to investigate the prevalence of antibiotic resistant enterobacteriaceae in the domestic food related environments.  methods: resistance to ampicillin, chloramphenicol, ciprofloxacin, gen...

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...

Rectal swabs were taken from healthy household dogs that, insofar as could be determined, had not received antimicrobial drugs. Tetracycline-resistant coliforms comprised 80 to 100% of the total number of coliforms in 61 (65%) of the 94 dogs sampled. The median number of other resistance determinants possessed by these tetracycline-resistant coliforms was 5.1. Of the tetracycline-resistant stra...

The antibiotic sensitivity of the individual organisms of a bacterial population was determined to study the comparative rates of development of resistance of Staphylococcus aureus to novobiocin, tetracycline, and to a combination of these antibiotics. Serial subculture of S. aureus with the combination of novobiocin-tetracycline (N-T 2.5:1; the ratio in serum of patients dosed with Panalba) sh...

The present study was done to evaluate the presence of antibiotic resistance genes in Lactococcus garvieae isolated from cultured rainbow trout, West Iran.The isolates were examined for antimicrobial resistance using disc diffusion method. Of the 24 strains tested, 21 were resistant to ampicillin (87.5%), 9 to erythromycin (37.5%) and 19 to tetracycline (79.1%). Fourteen strains were resistant ...

A series of novel tetracycline derivatives were synthesized with the goal of creating new antibiotics that would be unaffected by the known tetracycline resistance mechanisms. New C-9-position derivatives of minocycline (the aminomethylcyclines [AMCs]) were tested for in vitro activity against Gram-positive strains containing known tetracycline resistance mechanisms of ribosomal protection (Tet...