Polyuridylic acid directed protein synthesis by ribosomes from tetracyclinesensitive and tetracycline-resistant cells of Mycoplasma laidlawii B was found to be sensitive to tetracycline. The ribosomal preparations were somewhat more sensitive to tetracycline than mixtures of ribosomes and cell membrane fragments. No requirement for an exogenous m-RNAcould be demonstrated with the latter prepara...

Resistances to tetracycline and mercury were identified in an environmental strain of Serratia marcescens isolated from a stream highly contaminated with heavy metals. As a step toward addressing the mechanisms of coselection of heavy metal and antibiotic resistances, the tetracycline resistance determinant was cloned in Escherichia coli. Within the cloned 13-kb segment, the tetracycline resist...

Lactobacillus sakei is extensively used as functional starter culture in fermented meat products. One of the safety criteria of a starter culture is the absence of potentially transferable antibiotic resistance determinants. However, tetracycline-resistant L. sakei strains have already been observed. In this paper, we show that tetracycline resistance in L. sakei Rits 9, a strain isolated from ...

pMV120 was reported to carry the tetracycline resistance (Tcr) determinant of class N. We obtained tetracycline-susceptible transconjugants harboring plasmids with restriction enzyme profiles indistinguishable from those of pMV120 isolated from tetracycline-resistant clones. We conclude that pMV120 is a cryptic plasmid and that class N of Tcr determinants does not exist.

We have developed a tetracycline-repressible female-specific lethal genetic system in the vinegar fly Drosophila melanogaster. One component of the system is the tetracycline-controlled transactivator gene under the control of the fat body and female-specific transcription enhancer from the yolk protein 1 gene. The other component consists of the proapoptotic gene hid under the control of a tet...

objective(s): in this work, electrospun nanofibers were explored as drug delivery vehicles using tetracycline as a model drug.  nanocomposite fibers including chitosan (cs)/poly (ethylene oxide) (peo) and antibiotic were successfully prepared using electrospinning. cs blended with peo considering a weight ratio of (90/10), and then, nanofibrous samples were successfully electrospun from their a...

results the k. pneumonia isolates were resistant to erythromycin (70%), cefixime (53.3%), tetracycline (50%) and ceftazidime (36.6%). the amplification of teta and tetb genes of k. pneumonia revealed that all of the isolates harbored these genes. conclusions resistance to tetracycline and other antibiotics, and the presence of various resistance genes in k. pneumonia strains are alarming signs ...

Neisseria gonorrhoeae becomes resistant to tetracycline by two major mechanisms: expression of a plasmid-encoded TetM protein and mutations in endogenous genes (chromosomally mediated resistance). Early studies by Sparling and colleagues (P. F. Sparling F. A. J. Sarubbi, and E. Blackman, J. Bacteriol. 124:740-749, 1975) demonstrated that three genes were involved in high-level chromosomally med...

Tet(L) and Tet(K) are specific antibiotic-resistance determinants. They catalyze efflux of a tetracycline(Tc)-divalent metal complex in exchange for protons, as do other Tet efflux proteins. These Tet proteins also catalyze Na+ and K+ exchange for protons. Each of the "cytoplasmic substrates", Na+, K+ and the Tc-metal ion complex, can also be exchanged for K+, a catalytic mode that accounts for...