Tetracyclines infection site

Certain antimicrobial dmgs are actively transported into infection sites. The active transport of fluoroquinolones and tetracyclines by gingival fibroblasts into gingival fluid is an example. ... 

Minocycline, a tetracycline, is indicated in syphilis or gonorrhea in patients sensitive to penicillin. In addition, it may be used in uncomplicated urethral, endocervical, or rectal infection, and in uncomplicated gonococcal urethritis in men (see also Figure 96). Tetracyclines enter bacterial cells by both passive diffusion and active transport, and then accumulate intraceUularly. This does not occur in mammalian cells. The tetracyclines bind to the 308 subunit of the bacterial ribosome in such a way that the binding of the aminoacyl-transfer RNA to the acceptor site on the messenger RNA ribosome complex is blocked (see Figure 96). 

The antibiotic tetracycline binds to the 30S ribosomal subunit of prokaryotes and inhibits binding of aminoacyl-tRNA to the A site of the ribosome. The bacterium causing Neu Moania s infection was found to be sensitive to tetracycline. 

Tetracycline (Achromycin) Doxycycline (Vibramycin) Demeclocycline (Dedomycin) Minocycline (e.g., Minocin) Inhibits protein synthesis. Binds to 30s subunit blocking amino acid-linked tRNA from binding to the A site of the ribosome. Most Staphylococcus and Streptococcus strains, enterics, mycoplasma, spirochetes, rickettsiae. Not DOC for any microorganism. Used for acne and chlamydial infections in teens. 

Brucellosis is caused by three different gramnegative rods Brucella suis from pigs. B. abortus from cattle, and B. melitensis from sheep and goats. Infection is from handling infected animals or ingesting contaminated unpasteurized milk or cheese. The skin manifestations can include maculopapular lesions, petechiae, a chronic ulcer at the site of inoculation, and an urticarial eruption with subsequent vesiculopustules. Treatment is oral tetracycline plus intramuscular streptomycin. Prevention of brucellosis in humans is based on elimination of animal brucellosis. Immunization of animals is done using a live attenuated Brucella vaccine. 

---