Two fused proteins of dihydrofolate reductase (DHFR) with oligopeptides were prepared by a recombinant DNA method. One of these, DHFR-IQI, has three (Ile-Gln-Ile) and the other, DHFR-lek, has eight (Ile-Arg-Met-Tyr-Gly-Gly-Phe-Leu) additional amino acid residues at the C terminals; in both proteins, Cys152 of wild DHFR is replaced by Glu. The thermal transition of the proteins was measured by CD and DSC at pH 7.0 and compared with that of wild DHFR. The results show that the thermal stability of DHFR-IQI is the same as that of the wild DHFR and that of DHFR-lek is less than that of the former two DHFRs. Analysis of the DSC data of DHFR-IQI indicates that the thermal transition is a three-state one. Data from both DSC and CD measurements suggest the association of DHFR-lek molecules. Study holds ProTherm entries: 2803, 2804 Extra Details: additive : EDTA(0.2 mM),CD measurements are at 220nm Escherichia coli dihydrofolate reductase; Thermal stability
Submitter: Connie Wang
Submission Date: April 24, 2018, 8:20 p.m.
|Number of data points||4|
|Proteins||Dihydrofolate reductase ; Dihydrofolate reductase|
|Assays/Quantities/Protocols||Experimental Assay: Tm ; Experimental Assay: dHvH|
|Libraries||Mutations for sequence MISLIAALAVDRVIGMENAMPWNLPADLAWFKRNTLDKPVIMGRHTWESIGRPLPGRKNIILSSQPGTDDRVTWVKSVDEAIAACGDVPEIMVIGGGRVYEQFLPKAQKLYLTHIDAEVEGDTHFPDYEPDDWESVFSEFHDADAQNSHSYCFEILERR|