Thermodynamic characterization of the human acidic fibroblast growth factor: evidence for cold denaturation.


The thermodynamic parameters characterizing the conformational stability of the human acidic fibroblast growth factor (hFGF-1) have been determined by isothermal urea denaturation and thermal denaturation at fixed concentrations of urea using fluorescence and far-UV CD circular dichroism (CD) spectroscopy. The equilibrium unfolding transitions at pH 7.0 are adequately described by a two-state (native <--> unfolded state) mechanism. The stability of the protein is pH-dependent, and the protein unfolds completely below pH 3.0 (at 25 degrees C). hFGF-1 is shown to undergo a two-state transition only in a narrow pH range (pH 7.0-8.0). Under acidic (pH <6.0) and basic (pH >8.0) conditions, hFGF-1 is found to unfold noncooperatively, involving the accumulation of intermediates. The average temperature of maximum stability is determined to be 295.2 K. The heat capacity change (DeltaC(p)()) for the unfolding of hFGF-1 is estimated to be 2.1 +/- 0.5 kcal.mol(-1).K(-1). Temperature denaturation experiments in the absence and presence of urea show that hFGF-1 has a tendency to undergo cold denaturation. Two-dimensional (1)H-(15)N HSQC spectra of hFGF-1 acquired at subzero temperatures clearly show that hFGF-1 unfolds under low-temperature conditions. The significance of the noncooperative unfolding under acidic conditions and the cold denaturation process observed in hFGF-1 are discussed in detail. Study holds ProTherm entries: 11472, 11473, 11474, 11475, 11476, 11477, 11478, 11479, 11480, 11481, 11482, 11483, 11484, 11485, 11486, 11487, 11488, 11489, 11490 Extra Details: conformational stability; noncooperatively; cold denaturation; acidic

Submission Details


Submitter: Connie Wang

Submission Date: April 24, 2018, 8:42 p.m.

Version: 1

Publication Details
Chi Y;Kumar TK;Wang HM;Ho MC;Chiu IM;Yu C,Biochemistry (2001) Thermodynamic characterization of the human acidic fibroblast growth factor: evidence for cold denaturation. PMID:11412129
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 2 P09038 FGF2_HUMAN
100.0 Fibroblast growth factor 2 Q5IS69 FGF2_PANTR
98.7 Fibroblast growth factor 2 P03969 FGF2_BOVIN
98.1 Fibroblast growth factor 2 P20003 FGF2_SHEEP
97.3 Fibroblast growth factor 2 P13109 FGF2_RAT
96.6 Fibroblast growth factor 2 P15655 FGF2_MOUSE
92.9 Fibroblast growth factor 2 P48798 FGF2_MONDO
92.2 Fibroblast growth factor 2 P48800 FGF2_CHICK
99.3 Fibroblast growth factor 2 P48799 FGF2_RABIT
91.1 Fibroblast growth factor 2 Q60487 FGF2_CAVPO