title: Study on interaction of alpha-amylase from Bacillus subtilis with cetyl trimethylammonium bromide.
abstract: The interaction of cetyl trimethylammonium bromide (CTAB) with alpha-amylase from Bacillus subtilis was investigated at 25 degrees C and various experimental conditions, such as pH, ionic strength and urea concentration. The binding data were measured using CTAB-membrane selective electrodes as a simple, fast, cheap and accurate method. The obtained binding isotherms were analyzed using Wyman binding potential concept. The results represent the highest binding affinity at 10(-3) M of NaBr respect to other salt concentrations. The less binding affinity at pH 9.7 with respect to pH 6.5 is related to increasing of protein self aggregation with pH. The binding data analysis at various urea concentrations also shows that the predominate unfolding of alpha-amylase occurred in the urea concentration range of 3-5 M.
authors.affiliation: Department of Chemistry, University of Isfahan, Hezarjarib Avenue, Isfahan 81746-73441, Iran. bordbar@sci.ui.ac.ir
authors.forename: Abdol-Khalegh
authors.initials: AK
authors.lastname: Bordbar
authors.forename: Khodayar
authors.initials: K
authors.lastname: Omidiyan
authors.forename: Reza
authors.initials: R
authors.lastname: Hosseinzadeh
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology / Q000378:metabolism*; D001672:Biocompatible Materials / Q000737:chemistry*; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D007477:Ions; D011199:Potentiometry; D011485:Protein Binding; D011489:Protein Denaturation; D017510:Protein Folding; D013501:Surface-Active Agents / Q000737:chemistry; D013696:Temperature; D013816:Thermodynamics; D014508:Urea / Q000737:chemistry; D000516:alpha-Amylases / Q000737:chemistry* / Q000378:metabolism
chemical_list: D001672:Biocompatible Materials; D002593:Cetrimonium Compounds; D007477:Ions; D013501:Surface-Active Agents; D014508:Urea; D000516:alpha-Amylases; D000077286:Cetrimonium