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 Two of these mutations are in helix 3, where Gly-46 and Gly-48 have been replaced by alanines [Hecht, M. H., et al.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

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