Thermodynamic characterization of mutants of human fibroblast growth factor 1 with an increased physiological half-life.


Human acidic fibroblast growth factor (FGF-1) is a potent mitogen and angiogenic factor, with reportedly poor thermal stability and a relatively short in vivo half-life. However, certain mutants of FGF-1 have been described that exhibit a significant increase in half-life in tissue culture-based assays. FGF-1 contains three cysteine residues, two of which are highly conserved and buried within the protein core. Mutant forms of FGF-1 that substitute a serine residue at these cysteine positions have been reported to increase the protein's half-life and specific activity as well as decrease the dependence upon heparin for full activity. However, the underlying physical basis for this increase in half-life has not been determined. Possible effects include stabilization of protein structure and elimination of sulfhydryl chemistry at these positions. Here we have used differential scanning calorimetry and isothermal equilibrium denaturation to characterize thermodynamic parameters of unfolding for individual, and combination, cysteine to serine mutations in human FGF-1. The results show that substitution by serine is destabilizing at each cysteine position in wild-type FGF-1. Thus, the increased half-life previously reported for these mutations does not correlate with thermal stability and is most likely due to elimination of sulfhydryl chemistry. The results also suggest a method by which protein half-life may be modulated by rational design. Study holds ProTherm entries: 8288, 8289, 8290, 8291, 8292, 8293, 8294, 8295, 8296, 8297, 8298, 8299, 8300, 8301, 8302, 8303, 8304, 8305, 8306, 14474, 14475, 14476 Extra Details: Buffer ADA is N-(2-acetamido)iminodiacetic acid thermal stability; specific activity; sulfhydryl chemistry;,rational design

Submission Details


Submitter: Connie Wang

Submission Date: April 24, 2018, 8:35 p.m.

Version: 1

Publication Details
Culajay JF;Blaber SI;Khurana A;Blaber M,Biochemistry (2000) Thermodynamic characterization of mutants of human fibroblast growth factor 1 with an increased physiological half-life. PMID:10852713
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Fibroblast growth factor 1 P05230 FGF1_HUMAN
100.0 Fibroblast growth factor 1 Q5NVQ3 FGF1_PONAB
97.9 Fibroblast growth factor 1 P34004 FGF1_MESAU
98.0 Fibroblast growth factor 1 P20002 FGF1_PIG
96.4 Fibroblast growth factor 1 P61148 FGF1_MOUSE
96.4 Fibroblast growth factor 1 P61149 FGF1_RAT
92.3 Fibroblast growth factor 1 P03968 FGF1_BOVIN
90.7 Fibroblast growth factor 1 Q7M303 FGF1_SHEEP
90.3 Fibroblast growth factor 1 P19596 FGF1_CHICK
91.5 Fibroblast growth factor 1 Q9N1S8 FGF1_CAPCA