title: Evaluation of pendimethalin binding to human serum albumin: Insights from spectroscopic and molecular modeling approach.
abstract: Interaction of pendimethalin (PM) herbicide with the major transporter in human circulation, human serum albumin (HSA), was studied using fluorescence, circular dichroism (CD), and molecular modeling methods. The attenuation of the fluorescence intensity of HSA in the presence of PM revealed formation of the PM-HSA complex. Analysis of the fluorescence quenching data showed moderately strong binding affinity between PM and HSA. Both hydrophobic interactions and hydrogen bonding were suggested to stabilize the PM-HSA complex, based on thermodynamic data. Binding of PM to HSA induced perturbation in the microenvironment around the aromatic fluorophores as well as secondary and tertiary structural changes in the protein. Complexation of PM with HSA led to an increase in its thermal stability. Both site marker displacement and molecular modeling results suggested site I, located in subdomain IIA as the preferred binding site of PM on HSA.
authors.affiliation: Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Wei Qi
authors.initials: WQ
authors.lastname: Lee
authors.affiliation: Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Ida Syazwani M
authors.initials: IS
authors.lastname: Affandi
authors.affiliation: Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Shevin R
authors.initials: SR
authors.lastname: Feroz
authors.affiliation: Bioinformatics Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.|Centre of Research for Computational Sciences and Informatics for Biology, Bioindustry, Environment, Agriculture and Healthcare (CRYSTAL), University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Saharuddin B
authors.initials: SB
authors.lastname: Mohamad
authors.affiliation: Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.|Centre of Research for Computational Sciences and Informatics for Biology, Bioindustry, Environment, Agriculture and Healthcare (CRYSTAL), University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Saad
authors.initials: S
authors.lastname: Tayyab
mesh_terms: D000814:Aniline Compounds / Q000378:metabolism*; D001665:Binding Sites; D002942:Circular Dichroism; D006801:Humans; D008958:Models, Molecular; D011485:Protein Binding; D012709:Serum Albumin / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
chemical_list: D000814:Aniline Compounds; D012709:Serum Albumin; C030856:pendimethalin
keywords: fluorescence quenching; herbicide; human serum albumin; ligand-protein interaction; pendimethalin