Experimental charge density of selected amino acids

Temporary anion states of selected amino acids

Experimental charge density of N-phenylurea

Urea and its derivatives have been the subject of extensive experimental and theoretical studies, using many techniques, mainly because of interesting physical and chemical properties [1-4]. Here we report a preliminary results of charge density study of N-phenylurea using synchrotron diffraction data collected at beamline F1 at HASYLAB/DESY. Although known from literature [1], the structure wa...

Charge-Transfer Interactions of Aliphatic Amino Acids with Metal Ions

The effect of various non-SH-containing amino acids on an electron spin resonance spectrum as well as on an optical absorption spectrum of an aqueous copper (II) solution was investigated. The data obtained indicate that a charge-transfer complex is formed with amino acids acting as electron donors. A plot of the wavelength of the CT-band vs. the pK values of the carboxyl group exhibits a strai...

Experimental charge density from electron microscopic maps.

The charge density (CD) distribution of an atom is the difference per unit volume between the positive charge of its nucleus and the distribution of the negative charges carried by the electrons that are associated with it. The CDs of the atoms in macromolecules are responsible for their electrostatic potential (ESP) distributions, which can now be visualized using cryo-electron microscopy at h...

Release of selected amino acids from zinc carriers.

The paper deals with the results of an investigation of the release of selected amino acids (histidine, tryptophan, tyrosine) from model suspensions prepared by co-precipitation with zinc chloride. It has been proven that the influence of the Zn(II)/amino acid molar ratio on dissolution profiles of the tested amino acids and dissolution half-life (t1/2) of histidine or tryptophan is significant...