Forty-nine surface sediment samples from the Minho estuary sector between Tui and Caminha were analyzed for grain-size contents, Al, As, Cr, Cu, Hg, Li, Pb, Sn, and Zn concentrations. Selected heavy metal (Cu, Cr, Hg, and Zn) and metalloid (As and Sn) distributions were normalized against Al and Li with the main goal of compensating for natural grain-size variability and to separate natural fro...

Kirromycin, a new inhibitor of protein synthesis, is shown to interfere with the peptide transfer reaction by acting on elongation factor Tu (EF-Tu). All the reactions associated with this elongation factor are affected. Formation of the EF-Tu.GTP complex is strongly stimulated. Peptide bond formation is prevented only when Phe-tRNA(Phe) is bound enzymatically to ribosomes, presumably because G...

The translation elongation factor EF-Tu is a GTPase that delivers amino-acylated tRNAs to the ribosome during the elongation step of translation. EF-Tu/GDP is recycled by the guanine nucleotide exchange factor EF-Ts. Whereas EF-Ts is lacking in S. cerevisiae, both translation factors are found in S. pombe and H. sapiens mitochondria, consistent with the known similarity between fission yeast an...

This paper describes the concentration of selected heavy metals (Co, Cu, Ni, Pb, and Zn) in the Mamut river sediments and evaluate the degree of contamination of the river polluted by a disused copper mine. Based on the analytical results, copper showed the highest concentration in most of the river samples. A comparison with Interim Canadian Sediment Quality Guidelines (ICSQG) and Germany Sedi...

The structural gene for anthrax edema factor (EF) was expressed in Escherichia coli under the control of a powerful T5 promoter to yield the 89-kDa recombinant protein that reacted with anti-EF antibodies. Recombinant EF was purified to homogeneity by a two-step procedure involving metal chelate affinity chromatography and cation-exchange chromatography. From 1 liter of culture, 2.5 mg of biolo...

The amino acid sequence of LepA protein, which has been shown to be cotranscribed with signal peptidase I in Escherichia coli, was compared with greater than 2000 known protein sequences. It was revealed that, of the 598 amino acid residues contained in LepA, an amino-terminal domain of 112 residues is homologous to a domain of similar size found in initiation factor 2, elongation factor Tu, an...

Executive function (EF) has long been considered to be a unitary, domain-general cognitive ability. However, recent research suggests differentiating "hot" affective and "cool" cognitive aspects of EF. Yet, findings regarding this two-factor construct are still inconsistent. In particular, the development of this factor structure remains unclear and data on school-aged children is lacking. Furt...