oxytetracycline--anhydrous and Corynebacterium-Infections

To determine oxytetracycline concentrations in plasma and in fluid from. 10 clinically normal female sheep.. Sterile tissue chambers were surgically implanted in both paralumbar fossae of each sheep; ≥ 2 weeks later (day -6), 1 randomly selected chamber was inoculated with CPT, and the opposite chamber was injected with sterile growth medium. Sheep received oxytetracycline IM (n = 5) or by percutaneous injection into CPT-inoculated (4) or uninoculated (1) chambers on day 0. Tissue fluid from each chamber and venous blood samples for plasma collection were obtained at predetermined times over 6 days for bacterial counts (tissue chambers) and analysis of oxytetracycline concentrations (tissue chambers and plasma). Sheep were euthanized on day 6. Regional lymph nodes were collected bilaterally from each sheep for culture.. Measurable concentrations of oxytetracycline were present in each chamber throughout the study, regardless of administration route or presence of CPT. No CPT growth was detected after the 48-hour time point in inoculated chambers injected with oxytetracycline; however, CPT was isolated from all inoculated chambers throughout the study after IM drug administration. One regional lymph node (ipsilateral to a CPT-inoculated, oxytetracycline-injected chamber with no CPT growth after 48 hours) was culture positive for CPT.. Intralesional administration of oxytetracycline may eliminate growth of CPT locally, but complete elimination of the organism remains difficult.

Topics: Abscess; Animals; Anti-Bacterial Agents; Corynebacterium Infections; Corynebacterium pseudotuberculosis; Disease Models, Animal; Extracellular Fluid; Female; Injections, Intralesional; Injections, Intramuscular; Lymphadenitis; Oxytetracycline; Random Allocation; Sheep; Sheep Diseases

The tetracycline resistance region of the 50-kb R-plasmid pTP10 from the clinical isolate Corynebacterium striatum M82B was analyzed in Corynebacterium glutamicum ATCC 13032 and confined to a 4.4-kb SphI-Sa/I DNA fragment. Nucleotide sequence analysis revealed two open reading frames, termed tetA and tetB, specifying proteins of 513 and 528 amino acids, respectively. The deduced amino acid sequences of tetAB displayed similarity to ATP-binding cassette transporters including StrV and StrW of Streptomyces glaucescens which are proposed to play a role in the export of streptomycin-like aminoglycosides. An antibiotic susceptibility screening in C. glutamicum showed that the tetAB genes confer resistance to tetracycline, oxytetracycline and to the structurally and functionally unrelated beta-lactam antibiotic oxacillin.

Topics: Amino Acid Sequence; Anti-Bacterial Agents; Antiporters; ATP-Binding Cassette Transporters; Bacterial Proteins; Corynebacterium; Corynebacterium Infections; Drug Resistance, Multiple; Genes, Bacterial; Humans; Microbial Sensitivity Tests; Molecular Sequence Data; Oxacillin; Oxytetracycline; Penicillin Resistance; Penicillins; R Factors; Sequence Alignment; Sequence Analysis, DNA; Tetracycline; Tetracycline Resistance

Topics: Animals; Cortisone; Corynebacterium; Corynebacterium Infections; Mice; Oxytetracycline; Yersinia pseudotuberculosis Infections