Consequences of single-site mutations in the intestinal fatty acid binding protein.

The intestinal fatty acid binding protein (IFABP) is a small (15 kDa) protein consisting mostly of 10 antiparallel beta-strands (A-J) and a small helical region that serves as a portal for the ligand. Two beta-sheet structures (strands A-E and F-J) surround a cavity into which the ligand binds. In this work, we investigated how changes in the side chains of specific residues are propagated through the structure.