The visual pigment rhodopsin is unique among the G protein-coupled receptors in having an 11-cis retinal chromophore covalently bound to the protein through a protonated Schiff base linkage. The chromophore locks the visual receptor in an inactive conformation through specific steric and electrostatic interactions. This efficient inverse agonist is rapidly converted to an agonist, the unprotona...

A chemically selective procedure for covalent modification of Schiff base-forming binding sites in proteins is demonstrated in vitro. In vivo studies show that the same procedure produces a selective anosmia ("odor blindness") when applied to the olfactory epithelia of experimental animals. Surgical experiments confirm that the sense of smell is specifically affected. The hypothesis that olfact...

BACKGROUND Based on the potential of Schiff base compounds to act as sources for the development of cancer chemotherapeutic agents, this in vivo study was performed to investigate the inhibitory properties of the synthetic Schiff base compound Cu(BrHAP)2 on colonic aberrant crypt foci (ACF). METHODOLOGY This study involved five groups of male rats. The negative control group was injected with...

An economical and environmental friendly method has been developed for the synthesis of Schiff base ligand N,N'bis(2-hydroxy-1-naphthylidene)-4-hydroxyphenylmethanediamine by one pot three components reaction of 2hydroxy-1-naphthaldehyde , 4-hydroxy benzaldehyde and ammonium acetate salt in the presence of triethyl amine under solvent free condition at room temperature. Cu(II), Ni(II) and Zn(II...

A series of iron(III) 1-D polymeric materials of the general formula [Fe(III)(Schiff-base)(L)](BPh(4)).n(CH(3)OH) (Schiff base = N,N'-ethylenebis(salicylaldimine) (H(2)salen), N,N'-o-phenylenebis(salicylaldimine) (H(2)salophen) and N,N'-ethylenebis(acety1acetone)-2,2'-imine (H(2) acen); L = bridging di-pyridyl or di-imidazole ligand, n = 0-4) and analogues therein, have been synthesised and str...

Metal chelates, [M(HL)2(H2O)2]X2 (where M= Mn(II), Co(II), Cu(II), Ni(II) or Zn(II), X= NO3–or Cl– and HL= Schiff base moiety), have been prepared and characterized by elemental analysis, magnetic and spectroscopic measurements (infrared, X-ray powder diffraction and scanning electron microscopy). Elemental analysis of the metal complexes was suggested that the stoichiometry is 1:2 (metal-ligan...

Fourier transform infrared difference spectroscopy has been used to obtain the vibrational modes in the chromophore and apoprotein that change in intensity or position between light-adapted bacteriorhodopsin and the K and M intermediates in its photocycle and between dark-adapted and light-adapted bacteriorhodopsin. Our infrared measurements provide independent verification of resonance Raman r...

Ribonuclease A has been used as a model protein for studying the specificity of glycation of amino groups in protein under physiological conditions (phosphate buffer, pH 7.4, 37 degrees C). Incubation of RNase with glucose led to an enhanced rate of inactivation of the enzyme relative to the rate of modification of lysine residues, suggesting preferential modification of active site lysine resi...

Recent studies with carbamazepine on human serum albumin (HSA) columns have noted an appreciable degree of non-specifi c binding on supports prepared by the Schiff base immobilization method. This work examines an alternative immobilization method for HSA based on N-hydroxysuccinimide (NHS)-activated silica. This support was prepared by reacting HPLC-grade silica directly with disuccinimidyl ca...