The influence of hepatocyte nuclear factor 3 (HNF3) on the level of transcriptional activity from the four hepatitis B virus promoters was investigated by transient-transfection analysis in the dedifferentiated hepatoma cell line, HepG2.1. It was found that the large surface antigen promoter and, to a much lesser extent, the nucleocapsid promoter were transactivated in the presence of HNF3. DNa...

mechanism of the binding of lomefloxacin (lmf) with human serum albumin has been studied at physiological ph (7.4) using fluorescence spectroscopic technique. lmf is a third-generation fluoroquinolone antibiotic that exhibits striking potency against a broad spectrum of gram-negative and gram-positive bacteria through inhibition of dna gyrase. lomefloxacin is a drug that is excreted in urine an...

The maintenance of the highly hydrophobic cell wall is central to the survival of Mycobacterium tuberculosis within its host environment. The antigen 85 proteins (85A, 85B, and 85C) of M. tuberculosis help maintain the integrity of the cell wall 1) by catalyzing the transfer of mycolic acids to the cell wall arabinogalactan and 2) through the synthesis of trehalose dimycolate (cord factor). Add...

apotransferrin (apo tf)  in 0.1 m n-(2hydroxyethyl)piperazine-n2-ethanesulfanic acid at 25 ˚c  and ph 7.4 has been titrated with acidic solution of tb3+. the binding of tb3+ at  the two specific metal-binding sites of transferrin was followed from the changes in the difference uv spectra at 245 nm. the molar absorptivity per binding site for tb3+-tf is 22,500 ± 1000 m-1cm-1. to determine the tb...

Objective(s): Nanobodies, the single domain antigen binding fragments of heavy chain-only antibodies occurring naturally in camelid sera, are the smallest intact antigen binding entities. Their minimal size assists in reaching otherwise largely inaccessible regions of antigens. However, their camelid origin raises a possible concern of immunogenicity when used for human therapy. Humanization is...

Determination of the nature of the antigen-antibody complex has always been the ultimate goal of three-dimensional epitope mapping studies. Various strategies for epitope mapping have been employed which include comparative binding studies with peptide fragments of antigens, binding studies with evolutionarily related proteins, chemical modifications of epitopes, and protection of epitopes from...

The binding behavior of a competitive inhibitor, N-phenylbenzhydroxamic acid (BHA) against horseradish peroxidase (HRP) was studied in order to understand and predict the interaction mechanism of hydrogen donors with the enzyme. The dissociation constants of the complexes of HRP-BHA, HRP-donor and HRP-BHA-azide were estimated at specified conditions by difference spectroscopy. The binding s...

To explore the possibility that the difference in antigen recognition between B and T cells derives from a structural difference in their respective antigen-specific receptors (immunoglobulins on B cells and immunoglobulin-like molecules on T cells), we compared the extracellular segments of the T-cell receptor alpha, beta, and gamma polypeptide chains and the N-terminal segment of the T-cell T...