ABSTRACT Several experimental methods have been used for studying the conformations taken by dipeptidic molecules when dissolved, at a very low concentration. in an inactive solvent such as carbon tetrachloride. Through systematic investigations performed by infrared and nmr spectroscopy. it has been possible to obtain accurate data about these conformations and to compare with the results of v...

Catalytic fields illustrate topology of the optimal charge distribution of a molecular environment reducing the activation energy for any process involving barrier crossing, like chemical reaction, bond rotation etc. Until now, this technique has been successfully applied to predict catalytic effects resulting from intermolecular interactions with individual water molecules constituting the fir...

Molecular dynamics simulations of myoglobin and aspartate aminotransferase, with explicit solvent, are shown to accurately reproduce the experimentally measured molar volumes. Single aminoacid substitution at VAL39 of aspartate aminotransferase is known to produce large volumetric changes in the enzyme, and this effect is demonstrated in simulation as well. This molecular dynamics approach, whi...

Early-onset primary dystonia is an inherited disorder characterized by involuntary twisting, repetitive movements and abnormal postures. It has recently been demonstrated that the DYT1 gene is the most relevant gene associated with primary generalized dystonia. The DYT1 gene product is a 332-aminoacid long protein, termed TorsinA, whose function is still not clear. Based on the results obtained...

When rabbit reticulocytes were incubated in vitro with [(3)H]acetate, their ribosomal proteins were rapidly acetylated within 10 min. Polyacrylamide-urea gel electrophoresis showed that several major ribosomal protein fractions were highly acetylated. By the double-isotope labeling technique, the incorporation of [(3)H]acetate and [(14)C]aminoacid mixture into ribosomal proteins and nascent cha...

An extracellular protease of Staphylococcus aureus, strain V8, previously shown to cleave specifically the peptide bonds on the carboxyl-terminal side of either aspartate or glutamate residues in phosphate buffer (pH 7.8) hydrolyzes only glutamoyl bonds in either ammonium bicarbonate (pH 7.8) or ammonium acetate (pH 4.0). Of all aspartoyl bonds tested, only the Asp-Gly linkage is cleaved at a d...

Triple A (Allgrove) syndrome was first described by Allgrove in 1978 in two pairs of siblings. Since then, about 100 cases have been reported, all of them displaying an autosomal recessive pattern of inheritance. Clinical picture is characterized by achalasia, alacrimia and ACTH-resistant adrenal failure. A progressive neurological syndrome including central, peripheral and autonomic nervous sy...

The interaction of L-aromatic aminoacids with bases and nucleosides is described. Of these, L-tryptophan interacts more strongly with bases and nucleosides as indicated by nuclear magnetic resonance, circular dichroism and solubility measurements. A possible ring-ring type interaction between the aminoacid and bases or nucleosides is proposed; this interaction being such that the hydrodinamic b...