The mechanism by which barnase and binase are stabilized in their complexes with barstar and the role of the Cys-40 residue of barstar in that stabilization have been investigated by scanning microcalorimetry. Melting of ribonuclease complexes with barstar and its Cys-82-Ala mutant is described by two 2-state transitions. The lower-temperature one corresponds to barstar denaturation and the higher-temperature transition to ribonuclease melting. The barstar mutation Cys-40-Ala, which is within the principal barnase-binding region of barstar, simplifies the melting to a single 2-state transition. The presence of residue Cys-40 in barstar results in additional stabilization of ribonuclease in the complex. Study holds ProTherm entries: 15000, 15001, 15002, 15003, 15004, 15005 Extra Details: DTT(1 mM) was added in the experiment barnase; binase; barstar mutant; protein-protein complex; thermal denaturation
Submitter: Connie Wang
Submission Date: April 24, 2018, 8:45 p.m.
|Number of data points||18|
|Proteins||Ribonuclease ; Barstar ; Ribonuclease ; Barstar ; Ribonuclease ; Ribonuclease|
|Assays/Quantities/Protocols||Experimental Assay: dHcal details:Additives ; Experimental Assay: Tm details:Additives ; Experimental Assay: dHvH details:Additives ; Experimental Assay: dHcal details:Additives DTT (1 mM), ; Experimental Assay: Tm details:Additives DTT (1 mM), ; Experimental Assay: dHvH details:Additives DTT (1 mM),|
|Libraries||Mutations for sequence KKAVINGEQIRSISDLHQTLKKELALPEYYGENLDALWDCLTGWVEYPLVLEWRQFEQSKQLTENGAESVLQVFREAKAEGCDITIILS ; Mutations for sequence AQVINTFDGVADYLQTYHKLPDNYITKSEAQALGWVASKGNLADVAPGKSIGGDIFSNREGKLPGKSGRTWREADINYTSGFRNSDRILYSSDWLIYKTTDHYQTFTKIR ; Mutations for sequence AVINTFDGVADYLIRYKRLPDNYITKSQASALGWVASKGNLAEVAPGKSIGGDVFSNREGRLPSASGRTWREADINYVSGFRNADRLVYSSDWLIYKTTDNYATFTRIR|