Cyclic lipoundecapeptide tensin from Pseudomonas fluorescens strain 96.578

The crystal structure of the non-ribosomal lipoundecapeptide tensin from Ps eudomonas fluorescens has been solved as an ethyl acetate/bis-water solvate (tensin ethyl acetate dihydrate, C67H115N12O20. C4H8O2. 2H(2)O) to a resol ution of 0.8 Angstrom. The primary structure of tens in is beta-hydroxydeca noyl-D-Leu-D-Asp-D-allo-Thr-D-Leu-D-Leu-D-Ser-L-Leu-D-Gln-L-Leu-Ile-L-Glu, The peptide is a lactone linking the Thr3 O-gamma atom to the C-terminal C atom. The stereochemistry of the beta-hydroxy acid has been shown to be S. The peptide shows structural resemblance to the non-ribosomal cyclic lipope ptide fengycin from Bacillus subtilis. The structure of tensin is essential ly helical (3(10)-helix), with the cyclic peptide wrapping around a hydroge n-bonded water molecule, The lipopeptide is amphipathic in good agreement w ith its function as a biosurfactant.