Key role of barstar Cys-40 residue in the mechanism of heat denaturation of bacterial ribonuclease complexes with barstar.


Abstract

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

Submission Details

ID: 2pwXrn4t3

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:45 p.m.

Version: 1

Publication Details
Protasevich II;Schulga AA;Vasilieva LI;Polyakov KM;Lobachov VM;Hartley RW;Kirpichnikov MP;Makarov AA,FEBS Lett. (1999) Key role of barstar Cys-40 residue in the mechanism of heat denaturation of bacterial ribonuclease complexes with barstar. PMID:10094494
Additional Information

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 PDB Entries

Structure ID Release Date Resolution Structure Title
1BUJ 1998-09-04T00:00:00+0000 0 STRUCTURE OF BINASE IN SOLUTION
1GOU 2001-10-26T00:00:00+0000 1.65 Ribonuclease Binase (G Specific Endonuclease) Unliganded Form
1GOV 2001-10-26T00:00:00+0000 2.0 RIBONUCLEASE BI(G SPECIFIC ENDONUCLEASE) COMPLEXED WITH SULFATE IONS
1GOY 2001-10-26T00:00:00+0000 2.0 HYDROLASE(ENDORIBONUCLEASE)RIBONUCLEASE BI(G SPECIFIC ENDONUCLEASE) (E.C.3.1.27.-) COMPLEXED WITH GUANOSINE-3'-PHOSPHATE (3'-GMP)
2RBI 1996-11-12T00:00:00+0000 2.2 STRUCTURE OF BINASE MUTANT HIS 101 ASN
4HAA 2012-09-26T00:00:00+0000 1.9 Structure of Ribonuclease Binase Glu43Ala/Phe81Ala Mutant
1A19 1997-12-25T00:00:00+0000 2.76 BARSTAR (FREE), C82A MUTANT
1AB7 1997-02-04T00:00:00+0000 0 NMR 15N RELAXATION AND STRUCTURAL STUDIES REVEAL CONFORMATIONAL EXCHANGE IN BARSTAR C40/82A, 30 STRUCTURES
1AY7 1997-11-14T00:00:00+0000 1.7 RIBONUCLEASE SA COMPLEX WITH BARSTAR
1B27 1998-12-04T00:00:00+0000 2.1 STRUCTURAL RESPONSE TO MUTATION AT A PROTEIN-PROTEIN INTERFACE

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Ribonuclease P00648 RNBR_BACAM
97.3 Ribonuclease P35078 RN_BACCI
100.0 Barstar P11540 BARS_BACAM
100.0 Ribonuclease P00649 RN_BACIN
99.1 Ribonuclease P48068 RN_BACPU
99.1 Ribonuclease P37203 RN_BACCO