• Title/Summary/Keyword: Binding parameters

Search Result 276, Processing Time 0.027 seconds

Binding of Acid Dyes by Crosslinked Poly(4-vinylpyridine) in Ethylene Glycol (에틸렌글리콜중에서 가교폴리(4-비닐피리딘)과 산성염료와의 결합)

  • Lee, Suk Kee;Kim, Woo Sik
    • Textile Coloration and Finishing
    • /
    • v.9 no.3
    • /
    • pp.27-32
    • /
    • 1997
  • Two poly(4-vinylpyridines) having different degree of crosslinking were prepared by radical copolymerization of 4-vinylpyridine with N, N'-tetramethylenebis-acrylamide as a crosslinker. The abilities of these crosslinked polymers to bind acid dyes (methyl orange, ethyl orange, and propyl orange) were investigated at various temperatures in ethylene glycol as the binding medium. From the equilibrium amounts, the first binding constants and thermodynamic parameters for the bindings were evaluated. The first binding constants and thermodynamic parameters were not varied with these dyes. This result indicates that there is no hydrophobic interaction between the crosslinked polymers and the dyes in ethylene glycol. However, the first binding constants showed bell-shaped curves againtst the binding temperatures. This result could be explained in terms of the crosslinked hole size with temperature variation.

  • PDF

Detection and Kinetics of Mucosal Pathogenic Bacteria Binding with Polysaccharides

  • Chung, Kyong-Hwan;Park, Jung-Soon;Hwang, Hyun-Soo;Kim, Jin-Chul;Lee, Ki-Young
    • Journal of Microbiology and Biotechnology
    • /
    • v.17 no.7
    • /
    • pp.1191-1197
    • /
    • 2007
  • The detection and kinetics of mucosal pathogenic bacteria binding on polysaccharide ligands were studied using a surface plasmon resonance biosensor. The kinetic model applied curve-fitting to the experimental surface plasmon resonance sensorgrams to evaluate the binding interactions. The kinetic parameters for the mucosal pathogenic bacteria (Pseudomonas aeruginosa, Pseudomonas fluorescens, Serratia marcescens) with the alginate ligand were determined from a kinetic model. In addition, the binding interactions of the mucosal pathogenic bacteria with polysaccharide binding pairs (Pseudomonas aeruginosa/alginate, Streptococcus pneumoniae/pneumococcal polysaccharide, Staphylococcus aureus/pectin) were also compared with their kinetic parameters. The rate constants of association for Pseudomonas aeruginosa with the alginate ligand were higher than those for Pseudomonas fluorescens. Serratia marcescens had no detectable interaction with the alginate ligand. The adhesion affinity of Pseudomonas aeruginosa with alginate was higher than that for the other binding pairs. The binding affinities of the pathogenic bacteria with their own polysaccharide were higher than that of Staphylococcus aureus with pectin. Measuring the contact angle was found to be a feasible method for detecting binding interactions between analytes and ligands.

Cyclic Voltammetric Investigation of Interactions between Bisnitroaromatic Compounds and ds.DNA

  • Janjua, Naveed Kausar;Akhter, Zareen;Jabeen, Fariya;Iftikhar, Bushra
    • Journal of the Korean Chemical Society
    • /
    • v.58 no.2
    • /
    • pp.153-159
    • /
    • 2014
  • Herein, the cyclic voltammetric (CV) investigations of structurally similar bisnitrocompounds (N3, N4, N5, N6, having different-$CH_2$-spacer length) is presented. CV study offered interesting interactional possibilities of bisnitrocompounds with chicken blood ds.DNA at physiological pH 4.7 and human body temperature, 310 K. The results indicated strong interaction by these symmetric molecules with ds.DNA and strength of binding is found to depend on length of $CH_2$ spacer group in their molecular structure. Thermodynamics derived from electrochemical binding parameters also favored the irreversible interactions. Moreover, threading intercalation mode of binding is suggested based on thermodynamic and kinetic binding parameters extracted from CV studies.

DNA-Binding and Thermodynamic Parameters, Structure and Cytotoxicity of Newly Designed Platinum(II) and Palladium(II) Anti-Tumor Complexes

  • Mansouri-Torshizi, Hassan;Saeidifar, Maryam;Khosravi, Fatemeh;Divsalar, Adeleh;Saboury, Ali.Akbar;Ghasemi, Zahra Yekke
    • Bulletin of the Korean Chemical Society
    • /
    • v.32 no.3
    • /
    • pp.947-955
    • /
    • 2011
  • The complexes [Pd(bpy)(Hex-dtc)]$NO_3$ and [Pt(bpy)(Hex-dtc)]$NO_3$ (bpy is 2,2'-bipyridine and Hex-dtc is hexyldithiocarbamato ligands) were synthesized and characterized by elemental analysis and spectroscopic studies. The cytotoxicity assay of the complexes has been performed on chronic myelogenous leukemia cell line, K562, at micromolar concentration. Both complexes showed cytotoxic activity far better than that of cisplatin under the same experimental conditions. The binding parameters of the complexes with calf thymus DNA (CT-DNA) was investigated using UV-visible and fluorescence techniques. They show the ability of cooperatively intercalating in CT-DNA. Gel filtration studies demonstrated that platinum complex could cleave the DNA. In the interaction studies between the Pd(II) and Pt(II) complexes with CT-DNA, several binding and thermodynamic parameters have been determined, which may provide deeper insights into the mechanism of action of these types of complexes with nucleic acids.

Effect of Glycyrrhizic Acid on Protein Binding of Diltiazem, Verapamil, and Nifedipine

  • Lee, Kyoung-Jin;Park, Hye-Jeong;Shin, Young-Hee;Lee, Chi-Ho
    • Archives of Pharmacal Research
    • /
    • v.27 no.9
    • /
    • pp.978-983
    • /
    • 2004
  • The effects of glycyrrhizic acid (GLZ) on protein binding of diltiazem, verapamil, and nifedipine were investigated. Protein binding studies (human serum, human serum albumin (HSA) and (X1-acid glycoprotein (AAG)) were conducted using the equilibrium dialysis method with and without addition of GLZ. The binding parameters, such as the number of moles of bound drug per mole of protein, the number of binding sites per protein molecule, and the association con-stant, were estimated using the Scatchard plot. The serum binding of nifedipine, verapamil, and diltiazem was displaced with addition of GLZ, and the decreases of Ks for serum were observed. GLZ decreased the association constants of three drugs for HSA and AAG, while the binding capacity remained similar with addition of GLZ. Although the characteristics of interaction were not clear, GLZ seemed to mainly affect HSA binding of nifedipine rather than AAG binding, while GLZ seemed to affect both AAG- and HSA-bindings of verapamil and dilt-iazem resulting in a serum binding displacement.

Binding Set Analysis for Interaction of Human Serum Albumin with Cethyl Trimethylammonium Bromide

  • Bordbar, Abdol-Khalegh;Sohrabi, Nasrin;Gharibi, Hossain
    • Bulletin of the Korean Chemical Society
    • /
    • v.25 no.6
    • /
    • pp.791-795
    • /
    • 2004
  • The binding of cethyl trimethylammonium bromide, (CTAB) with human serum albumin (HSA) has been investigated at 5 mM phosphate buffer pH 7.0, 27 $^{\circ}C$ and various ionic strength using ion selective membrane electrodes. This method is faster and much more accurate than equilibrium dialysis technique, so provides sufficient and accurate data for binding data analysis. A novel and simple method was introduced for resolution and characterization of binding sets on basis of binding capacity concept. The values of Hill binding parameters were estimated for each set and used for calculation of intrinsic binding affinity. The results interpreted on basis of nature of forces which interfered in the interaction and represent the existence of three and two binding sets for binding of CTAB at $10^{-4}$ and $10^{-3}$ M of NaBr, respectively.

The Effects of Isotypes and Regional Distribution of Antisperm Antibodies on Semen Parameters and Fertilizing Ability (항정자항체가 정액성상 및 수정능력에 미치는 영향)

  • Pang, Myung-Geol;Moon, Shin-Yong
    • Clinical and Experimental Reproductive Medicine
    • /
    • v.25 no.1
    • /
    • pp.1-8
    • /
    • 1998
  • To investigate the influences on semen parameters and fertilizing capacity of immunoglobulin (Ig) isotypes and regional distribution of antisperm antibody (ASA) on the human sperm surface. Sixty-seven ASA-positive patients were compared with 96 ASA-negative donors. ASAs in semen showed significant negative effects on both semen parameters and fertilizing capacity; in those with ASAs in the sperm head and/or tail, the reductions were significant. In the head as well as the tail, there was close correlation between fertilizing capacity and both IgG and IgA. Both semen parameters and fertilizing capacity are significantly affected by the presence of ASA in semen. In particular, antibodies IgG to sperm head and/or tail, and antibodies IgA to sperm tail appeared to have a highly detrimental effect on fertilizing capacity.

  • PDF

Study on the Protein Binding of Anti-cancer Agent, 2"-O-benzoylcinnamaldehyde, using Ultrafilteration and Flurescence Spectrometry

  • Ren , Shan;Kim, Dae-Duk;Lee, Chi-Ho
    • Proceedings of the PSK Conference
    • /
    • 2003.10b
    • /
    • pp.242.3-243
    • /
    • 2003
  • The compound of 2"-O-benzoylcinnamaldehyde(CB-ph) is a derivative of 2"-hydroxycinnamaldehyde whcih is a methanol extract of cinnamomum cassia blume. It"s a new anti-cancer agent which has been showed to inhibit the growth of various tumor cells in vitro and in vivo. In order to investigate the effective drug concentration and bio-distribution of CB-ph, the plasma protein binding was studied. In this study, the degree of the binding of Cb-ph to various serum proteins, the binding parameters, the binding site of CB-ph in human serum albumin, and the effect of some extensive protein-binding drugs on the protein binding of CB-ph in human serum ablumin were investigated respectively by ultrafilteration and fluorescence spectrometry. (omitted)

  • PDF

Backbone Dynamics and Model-Free Analysis of N-terminal Domain of Human Replication Protein A 70

  • Yoo, Sooji;Park, Chin-Ju
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.22 no.1
    • /
    • pp.18-25
    • /
    • 2018
  • Replication protein A (RPA) is an essential single-stranded DNA binding protein in DNA processing. It is known that N terminal domain of RPA70 (RPA70N) recruits various protein partners including damage-response proteins such as p53, ATRIP, Rad9, and MRE11. Although the common binding residues of RPA70N were revealed, dynamic properties of the protein are not studied yet. In this study, we measured $^{15}N$ relaxation parameters ($T_1,\;T_2$ and heteronuclear NOE) of human RPA70N and analyzed them using model-free analysis. Our data showed that the two loops near the binding site experience fast time scale motion while the binding site does not. It suggests that the protein binding surface of RPA70N is mostly rigid for minimizing entropy cost of binding and the loops can experience conformational changes.

Effects of Brazilin on Glucose Metabolism in Primary Cultured Rat Hepatocytes

  • Moon, Chang-Kiu;Lee, Soo-Hwan;Chung, Jin-Ho;Kim, Seong-Gon;Chung, Mung-Kiu;Moon, Chang-Hyun
    • Archives of Pharmacal Research
    • /
    • v.13 no.4
    • /
    • pp.355-358
    • /
    • 1990
  • In order to investigate the cellular mechanisms of hypoglycemic of brazilin, hepatocyte monolayer culture was introduced and, glycogen synthesis rate and insulin binding were measured as parameters. Glycogen synthesis and insulin sensitivity were remarkably augmented by the treatment of brazilin. Brazilin slightely increased insulin binding. Scatchard analysis revealed that this increase in insulin binding was not due to increase in the binding capacity but in binding affinity. These results suggest that the augmentation of hepatic glycogenesis and insulin sensitivity by brazilin may play an important role in the improvement of hyperglycemia.

  • PDF