title: The role of polymer size and hydrophobic end-group in PEG-protein interaction.
abstract: We investigated the interaction between polyethylene (glycol) (PEG) and human (HSA) and bovine serum albumin (BSA) in aqueous solution, using multiple spectroscopic methods and molecular modeling. The two important polymer characteristics, size and PEG hydrophobic end-group are studied in order to determine the effect of each one on PEG-protein interaction. The bindings of PEG and mPEG-anthracene with serum albumins occur via hydrophobic and H-bonding contacts with the binding affinity PEG-6000>mPEG-anthracene>PEG-3000 for BSA and EG-6000>PEG-3000>mPEG-anthracene for HSA. Modeling showed different protein binding sites are involved in PEG-BSA and PEG-HSA complexes. Several H-bonding systems between PEG and different amino acids are stabilizing polymer-protein complexes. The free binding energies of -6.48 (PEG-BSA) and -6.36 kcal/mol (PEG-HSA) showed that the interaction process is spontaneous at room temperature. Minor alterations of protein alpha-helix and beta-sheet structures were observed upon PEG complexation.
authors: Department of Chemistry-Physics, University of Québec at Trois-Rivières, C. P. 500, TR, Quebec, Canada G9A 5H7.
authors: L
authors: L
authors: Bekale
authors: Department of Chemistry-Physics, University of Québec at Trois-Rivières, C. P. 500, TR, Quebec, Canada G9A 5H7.
authors: D
authors: D
authors: Agudelo
authors: Department of Chemistry-Physics, University of Québec at Trois-Rivières, C. P. 500, TR, Quebec, Canada G9A 5H7. Electronic address: tajmirri@uqtr.ca.
authors: H A
authors: HA
authors: Tajmir-Riahi
mesh_terms: D000818:Animals; D000873:Anthracenes / Q000737:chemistry / Q000378:metabolism; D001667:Binding, Competitive; D002417:Cattle; D006801:Humans; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D015394:Molecular Structure; D008970:Molecular Weight; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000378:metabolism; D011108:Polymers / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012709:Serum Albumin / Q000737:chemistry / Q000378:metabolism; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism; D013053:Spectrophotometry; D017550:Spectroscopy, Fourier Transform Infrared; D013816:Thermodynamics
chemical_list: D000873:Anthracenes; D011108:Polymers; D012709:Serum Albumin; D012710:Serum Albumin, Bovine; D011092:Polyethylene Glycols; C034020:anthracene
keywords: Hydrophobicity; Modeling; PEG; Polymer; Serum albumin; Spectroscopy