Combining thermostable mutations increases the stability of lambda repressor.

Abstract

We have combined three mutations previously shown to stabilize lambda repressor against thermal denaturation. Two of these mutations are in helix 3, where Gly-46 and Gly-48 have been replaced by alanines [Hecht, M. H., et al. (1986) Proteins: Struct., Funct., Genet. 1, 43-46]. The other mutation, which replaces Tyr-88 with cysteine, allows the protein to form an intersubunit disulfide bond [Sauer, R. T., et al. (1986) Biochemistry 25, 5992-5998]. Calorimetric measurements show that the two alanine substitutions stabilize repressor by about 8 degrees C, that the disulfide bond stabilizes repressor by about 8 degrees C, and that the triple mutant is 16 degrees C more stable than wild-type repressor. Study holds ProTherm entries: 3928, 3929, 3930, 3931, 14253, 14254, 14255 Extra Details: thermostable mutations; cysteine; alanine substitutions;,disulfide bond

Submission Details

ID: adMWrkH83

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:23 p.m.

Version: 1

Publication Details
Stearman RS;Frankel AD;Freire E;Liu BS;Pabo CO,Biochemistry (1988) Combining thermostable mutations increases the stability of lambda repressor. PMID:3061460
Additional Information

Study Summary

Number of data points 19
Proteins Repressor protein cI ; Repressor protein cI
Unique complexes 4
Assays/Quantities/Protocols Experimental Assay: ddG ; Experimental Assay: dHcal ; Experimental Assay: Tm ; Experimental Assay: dHvH ; Derived Quantity: dTm
Libraries Mutations for sequence STKKKPLTQEQLEDARRLKAIYEKKKNELGLSQESVADKMGMGQSGVGALFNGINALNAYNAALLAKILKVSVEEFSPSIAREIYEMYEAVS

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 Repressor protein cI P03034 RPC1_LAMBD