Thermal unfolding of the cytotoxin alpha-sarcin: phospholipid binding induces destabilization of the protein structure.


Abstract

The effect of membrane binding on the structure and stability of the cytotoxin alpha-sarcin has been studied by differential scanning calorimetry, Fourier-transform infrared and fluorescence spectroscopic techniques. The thermal unfolding of alpha-sarcin in aqueous solution fits into a two-state transition characterized by a transition temperature (Tm) of 52.6 degrees C and a calorimetric enthalpy (delta Hcal) of 136 kcal/mol. Upon interaction with phosphatidylglycerol vesicles, alpha-sarcin undergoes conformational changes, as deduced from the FTIR and fluorescence emission spectra. These changes result in a decreased Tm and delta Hcal values for the thermal unfolding of phospholipid-bound alpha-sarcin. The lower Tm value for lipid-bound alpha-sarcin is also observed at the level of secondary and tertiary structures, based on analyses of both the amide I' infrared spectrum and the tryptophan emission of the protein as a function of temperature, respectively. The results obtained indicate a protein destabilization promoted by the phospholipid interaction. Study holds ProTherm entries: 9370 Extra Details: additive : EDTA(1 mM), protein calorimetry; infrared spectroscopy of protein;,protein-lipid interaction; ribosome-inactivating protein

Submission Details

ID: zMA3Lbft

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:37 p.m.

Version: 1

Publication Details
Gasset M;Mancheño JM;Laynez J;Lacadena J;Fernández-Ballester G;Martinez del Pozo A;Oñaderra M;Gavilanes JG,Biochim. Biophys. Acta (1995) Thermal unfolding of the cytotoxin alpha-sarcin: phospholipid binding induces destabilization of the protein structure. PMID:7548154
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
1DE3 2000-06-21 SOLUTION STRUCTURE OF THE CYTOTOXIC RIBONUCLEASE ALPHA-SARCIN
1R4Y 2004-04-06 SOLUTION STRUCTURE OF THE DELETION MUTANT DELTA(7-22) OF THE CYTOTOXIC RIBONUCLEASE ALPHA-SARCIN

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Ribonuclease alpha-sarcin P00655 RNAS_ASPGI