Biomaterial Database

Interaction of myo-inositol hexaphosphate (MIHP) with beta-globulin from Sesamum indicum L. Kinetics and thermodynamics. 1993

S Rajendran, and V Prakash

Food Chemistry Department, Central Food Technological Research Institute, Mysore, India.

beta-Globulin, the low molecular weight protein fraction from Sesamum indicum L., interacts with myo-inositol hexaphosphate (MIHP) maximally at pH 3.0, with concomitant precipitation up to 85 +/- 2% at an MIHP concentration of 8 x 10(-4) M. The kinetics of interaction as followed by stopped-flow spectrophotometry suggested the reaction to be of pseudo first-order, having an initial fast step followed by a relatively slow step of rate constants 1.9 x 10(-2) s-1 and 1.2 x 10(-3) s-1, respectively at 1 x 10(-4) M MIHP concentration. The analysis of the complex indicated the presence of polymer as seen in sedimentation velocity experiment. This was accompanied by conformational change of a three-fold decrease in beta-structure and also an increase in fluorescence emission intensity accompanied with a red shift from 330 to 334 nm. Stoichiometric analysis of MIHP binding suggested four independent binding sites for MIHP, with a free energy change, delta G zero = 5.1 kcal mol-1 resulting from a binding constant of 3.6 x 10(3) M-1.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010833	Phytic Acid	Complexing agent for removal of traces of heavy metal ions. It acts also as a hypocalcemic agent.	Inositol Hexaphosphate,Phytin,Calcium Phytate,Inositol Hexakisphosphate,Phytate,Sodium Phytate,Acid, Phytic,Hexakisphosphate, Inositol,Hexaphosphate, Inositol,Phytate, Calcium,Phytate, Sodium
D010944	Plants	Multicellular, eukaryotic life forms of kingdom Plantae. Plants acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations. It is a non-taxonomical term most often referring to LAND PLANTS. In broad sense it includes RHODOPHYTA and GLAUCOPHYTA along with VIRIDIPLANTAE.	Plant
D011232	Chemical Precipitation	The formation of a solid in a solution as a result of a chemical reaction or the aggregation of soluble substances into complexes large enough to fall out of solution.	Precipitation, Chemical
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D001609	Beta-Globulins	Serum proteins with an electrophoretic mobility that falls between ALPHA-GLOBULINS and GAMMA-GLOBULINS.	Beta(1)CA Globulin,Beta-Globulin,Beta Globulin,Beta Globulins
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D013816	Thermodynamics	A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)	Thermodynamic