Wen J, Chen X, Bowie J U
Department of Chemistry and Biochemistry, University of California, Los Angeles 90095-1570, USA.
Nat Struct Biol. 1996 Feb;3(2):141-8. doi: 10.1038/nsb0296-141.
We present a comprehensive view of the tolerance of a membrane protein to sequence substitution. We find that the protein, diacylglycerol kinase from Escherichia coli, is extremely tolerant to sequence changes with three-quarters of the residues tolerating non-conservative changes. The conserved residues are distributed with approximately the same frequency in the soluble and transmembrane portions of the protein, but the most critical active-site residues appear to residue in the second cytoplasmic domain. It is remarkable that a unique structure of the membrane embedded portion of the protein can be encoded by a sequence that is so tolerant to substitution.
