Range 
7.1 E. coli: 8.8 S. cerevisiae: 8:2 C. elegans kcal/mol

Organism 
Various 
Reference 
Ghosh K, Dill K. Cellular proteomes have broad distributions of protein stability. Biophys J. 2010 Dec 15 99(12):39964002. p.3997 left column 1st paragraph under "Results"PubMed ID21156142

Method 
For E. coli, at 37°C, the average protein has a folding
free energy of <?G>=11.9RT~7.1kcal/mol, where
RT is the gas constant multiplied by absolute temperature
(for which researchers used T=300 K here). For yeast (Saccharomyces
cerevisiae (SCE)), for which <L>~475 and a=1.56, the average stability is <?G>=14.7RT~8.8kcal/mol. For the worm (Caenorhabditis elegans (CEL)), for which
<L>~425 and a=1.23, the average protein stability is
<?G>=13.7RT~8.2kcal/mol. Where <L> is the chain length and in the case of gamma distribution, the protein length variation can be
measured by a shape parameter, a. The lower the a value,
the greater the variation (Zhang 2000). 
Comments 
The standard deviations of the stability distributions
are 4.3 RT, 7.5 RT, and 7.5 RT for E. coli, yeast, and worm,
respectively. 
Entered by 
Uri M 
ID 
107069 