Recently, we reported on the induction by kirromycin of two tRNA binding sites on elongation factor Tu. To obtain independent information on the existence of these two sites and to characterize them further, 3' oxidized tRNA was cross-linked to elongation factor Tu by [3H]borohydride reduction. Specific cross-linking occurred exclusively in the presence of kirromycin. In the case of elongation ...

Data published by others have shown that thiouracil (TU) is taken up selectively during melanin synthesis following trace doses of labeled TU. The concentration in newly forming mel anin has been attributed to the incorporation of TU as a "false precursor" in the biosynthetic pathway of melanin. Information made available previously has been in terms of relative values in various tissues rather...

Elongation factor Ts (EF-Ts) is the guanine nucleotide exchange factor for elongation factor Tu (EF-Tu). An important feature of the nucleotide exchange is the structural rearrangement of EF-Tu in the EF-Tu.EF-Ts complex caused by insertion of Phe-81 of EF-Ts between His-84 and His-118 of EF-Tu. In this study, the contribution of His-118 to nucleotide release was studied by pre-steady state kin...

Using a 30-year record of biological and water chemistry data collected from seven lakes near smelters in Sudbury (Ontario, Canada) we examined the link between reductions of Cu, Ni, and Zn concentrations and zooplankton species richness. The toxicity of the metal mixtures was assessed using an additive Toxic Unit (TU) approach. Four TU models were developed based on total metal concentrations ...

Various isoforms of the glycolytic enzyme pyruvate kinase are expressed in different cell types. One of these isoforms, Tu M2-PK, is over-expressed in tumor cells and released into body fluids. Plasma determination of Tu M2-PK has been shown to discriminate between benign and malignant lesions. Tu M2-PK was quantitated in the plasma of 50 patients with cervical carcinoma, 10 patients with chron...