Recombinant human interleukin 1 beta has been studied in solution with respect to its conformation, stability, and characteristics of unfolding and refolding. It is an all-beta-type, stable globular protein with a high cooperativity under conditions where refolding is reversible. The tryptophan residue is approximately 40% exposed to solvent, and the four tyrosines are 50% exposed. The fluorescence of the single tryptophan residue is quenched at pH 7.5 but dequenched by high salt, by titration to lower pH with a pK of 6.59, and by denaturants, resulting in an unusual biphasic change in fluorescence on unfolding. Both histidine and thiol residues have been excluded as being responsible for the pH dependence of fluorescence by site-directed mutagenesis and by chemical modification, respectively. The likely candidate is an aspartate or glutamate. Study holds ProTherm entries: 3866 Extra Details: all-beta-type; cooperativity ; biphasic change;,chemical modification
Submitter: Connie Wang
Submission Date: April 24, 2018, 8:23 p.m.
|Number of data points||2|
|Proteins||Interleukin-1 beta ; Interleukin-1 beta|
|Assays/Quantities/Protocols||Experimental Assay: Cm ; Experimental Assay: dG_H2O|
|Libraries||Mutations for sequence APVRSLNCTLRDSQQKSLVMSGPYELKALHLQGQDMEQQVVFSMSFVQGEESNDKIPVALGLKEKNLYLSCVLKDDKPTLQLESVDPKNYPKKKMEKRFVFNKIEINNKLEFESAQFPNWYISTSQAENMPVFLGGTKGGQDITDFTMQFVSS|