title: Interaction of bovine serum albumin and albumin-gold nanoconjugates with l-aspartic acid. A spectroscopic approach.
abstract: The interaction of an essential transport protein bovine serum albumin (BSA) and albumin-gold nanoconjugates (BSA-GNPs) with amino acid l-aspartic (ASP) are investigated by steady state and time resolved spectroscopic techniques. In both the cases, static fluorescence quenching is observed indicating that a ground state complex is formed between the donor BSA/BSA-GNP with the acceptor ASP. High values of quenching constant suggest that energy transfer also occurred from BSA and BSA-GNPs to ASP. Distance between the fluorophore in the protein and the amino acid (ASP) is evaluated. Binding constants and the number of binding sites were determined in both the cases. The observed thermodynamic parameters suggest that the key interacting forces involved in both cases are hydrophobic interactions. Circular dichroism (CD) spectrum of BSA molecule suffers marginal change in the presence of ASP both in its pure as well as bio-nanoconjugate forms. As no structural deformation is occurred, the biological activity along with the activity of immune response of protein and the biocompatibility of protein-nanoconjugate remain as such.
authors.affiliation: Department of Spectroscopy, Indian Association for the Cultivation of Science, 2A and 2B Raja SC Mullick Road, Jadavpur, Kolkata, West Bengal 700032, India.
authors.forename: Gopa
authors.initials: G
authors.lastname: Mandal
authors.forename: Munmun
authors.initials: M
authors.lastname: Bardhan
authors.forename: Tapan
authors.initials: T
authors.lastname: Ganguly
mesh_terms: D000465:Algorithms; D000818:Animals; D001224:Aspartic Acid / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D002417:Cattle; D002942:Circular Dichroism; D004735:Energy Transfer; D006046:Gold / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D053768:Metal Nanoparticles / Q000737:chemistry; D008956:Models, Chemical; D058726:Nanoconjugates / Q000737:chemistry*; D011485:Protein Binding; D012710:Serum Albumin, Bovine / Q000737:chemistry* / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D013816:Thermodynamics; D014364:Tryptophan / Q000737:chemistry / Q000378:metabolism
chemical_list: D058726:Nanoconjugates; D012710:Serum Albumin, Bovine; D001224:Aspartic Acid; D006046:Gold; D014364:Tryptophan