The binding of Al3+ by human serum transferrin has been investigated by u.v.-visible difference spectroscopy. In the presence of 25 mM-HCO3- at pH 7.4, the apparent association constants were found to be 1.69 x 10(12) M-1 and 5.36 x 10(11) M-1. These association constants are pH-dependent, reducing with both increasing and decreasing pH. The apparent pKa values were found to be 6.7 and 8.2. Com...

We describe an anion channel in the plasmalemma of protoplasts isolated from wheat (Triticum aestivum L.) roots that is activated by aluminum (Al3+). In the whole-cell configuration, addition of 20-50 microM AlCl3 to the external solution depolarized the membrane and activated an inward current that could remain active for more than 60 min. The activation by Al3+ was rapid in 20% of protoplasts...

The effect of different metal ions on the intestinal transport and the antibacterial activity of cefadroxil [(6R,7R)-7-{[(2R)-2-amino-2-(4-hydroxyphenyl)acetyl]amino}-3-methyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid] was investigated. The [14C]Gly-Sar uptake via PEPT1 was inhibited by Zn2+ and Cu2+ treatment in a concentration-dependent manner (Ki values 107 ± 23 and 19 ± 5 ...

Previous studies showed that prolonged exposure to fluoride (F-) and aluminum (Al3+) ions is associated with numerous diseases including neurological disorders. They don't have any known biological function. But they can bind with proteins that interact with ions similar to them. Such unwanted interactions affect the normal biological function of the target proteins, as well as their downstream...

A sensitive and accurate potentiometric reaction-rate method for the assay of peroxidase (EC 1.11.1.7) and peroxidase-coupled reactions is described. The technique is based on the peroxidase-catalyzed rupture of the covalent C-F bond in certain organo-fluoro compounds in the presence of H202 and the measurement of liberated F by a fluoride ion-selective electrode. In a study screening 26 organo...

Hund's term rules are only valid for isolated atoms, but have no generalization for molecules or clusters of several atoms. We present a benchmark calculation of Al2 and Al3, for which we find the high and low-spin ground states (3)Πu and , respectively. We show that the relative stabilities of all the molecular terms of Al2 and Al3 can be described by simple rules pertaining to bonding structu...

The co-extraction phenomenon was found in a typical chelate extraction system, in which the extraction of lanthanoid ion (Ln3+) with acetylacetone (Hacac) was highly enhanced by various metal ions (M(n+)) such as Cu2+, Al3+, and Zr4+. This phenomenon was ascribed to the formation of the 1:1 adduct between Ln(acac)3 and the M(acac),, extracted into the organic phase. The co-extraction occurred m...

About a decade ago, members of a new protein family of anion channels were discovered on the basis of their ability to confer on plants the tolerance toward toxic aluminum ions in the soil. The efflux of Al3+-chelating malate anions through these channels is stimulated by external Al3+ ions. This feature of a few proteins determined the name of the entire protein family as Aluminum-activated Ma...

the preparation of polymer membrane selective to iron(ii) ion and its application to ion-selectiveelectrode is reported here. pvc membrane contains iron–selective n-phenylaza-15-crown-5 asionophore. the membrane electrode is highly selective to iron(ii) ion and exhibit good linearresponse over a wide concentration range of 1.0 × 10-2 to 1.0 × 10-6 m with nernstian slope of29.2 ± 0.6 mv per deca...