title: An empirical phase diagram approach to investigate conformational stability of "second-generation" functional mutants of acidic fibroblast growth factor-1.
abstract: Acidic fibroblast growth factor-1 (FGF-1) is an angiogenic protein which requires binding to a polyanion such as heparin for its mitogenic activity and physicochemical stability. To evaluate the extent to which this heparin dependence on solution stability could be reduced or eliminated, the structural integrity and conformational stability of 10 selected FGF-1 mutants were examined as a function of solution pH and temperature by a series of spectroscopic methods including circular dichroism, intrinsic and extrinsic fluorescence spectroscopy and static light scattering. The biophysical data were summarized in the form of colored empirical phase diagrams (EPDs). FGF-1 mutants were identified with stability profiles in the absence of heparin comparable to that of wild-type FGF-1 in the presence of heparin while still retaining their biological activity. In addition, a revised version of the EPD methodology was found to provide an information rich, high throughput approach to compare the effects of mutations on the overall conformational stability of proteins in terms of their response to environmental stresses such as pH and temperature.
authors: Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, Kansas 66047, USA.
authors: Mohammad A
authors: MA
authors: Alsenaidy
authors: Tingting
authors: T
authors: Wang
authors: Jae Hyun
authors: JH
authors: Kim
authors: Sangeeta B
authors: SB
authors: Joshi
authors: Jihun
authors: J
authors: Lee
authors: Michael
authors: M
authors: Blaber
authors: David B
authors: DB
authors: Volkin
authors: C Russell
authors: CR
authors: Middaugh
mesh_terms: D055592:Biophysical Phenomena; D002942:Circular Dichroism; D016220:Fibroblast Growth Factor 1 / Q000737:chemistry* / Q000235:genetics / Q000494:pharmacology; D006493:Heparin / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009154:Mutation; D011485:Protein Binding; D011487:Protein Conformation; D055550:Protein Stability; D013050:Spectrometry, Fluorescence; D013696:Temperature
chemical_list: D016220:Fibroblast Growth Factor 1; D006493:Heparin