Discrimination of thermophilic and mesophilic proteins.
BACKGROUND
There is a considerable literature on the source of the thermostability of proteins from thermophilic organisms. Understanding the mechanisms for this thermostability would provide insights into proteins generally and permit the design of synthetic hyperstable biocatalysts.


RESULTS
We have systematically tested a large number of sequence and structure derived quantities for their ability to discriminate thermostable proteins from their non-thermostable orthologs using sets of mesophile-thermophile ortholog pairs. Most of the quantities tested correspond to properties previously reported to be associated with thermostability. Many of the structure related properties were derived from the Delaunay tessellation of protein structures.


CONCLUSIONS
Carefully selected sequence based indices discriminate better than purely structure based indices. Combined sequence and structure based indices improve performance somewhat further. Based on our analysis, the strongest contributors to thermostability are an increase in ion pairs on the protein surface and a more strongly hydrophobic interior.
Taylor
Todd J
TJ
National Cancer Institute, Laboratory of Molecular Biology, 37 Convent Dr, MS 4264, Bethesda, MD 20892, USA. todd.taylor@nih.gov
Vaisman
Iosif I
II
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry; D008958:Models, Molecular; D010735:Phosphoglycerate Kinase / Q000737:chemistry; D011487:Protein Conformation; D055550:Protein Stability; D011506:Proteins / Q000737:chemistry*; D019711:Pyrococcus / Q000737:chemistry; D035181:TATA-Box Binding Protein / Q000737:chemistry; D013696:Temperature; D014346:Trypanosoma brucei brucei / Q000737:chemistry
D001426:Bacterial Proteins; D011506:Proteins; D035181:TATA-Box Binding Protein; D010735:Phosphoglycerate Kinase