Solution conformation of the Pseudomonas syringae MSU 16H phytotoxic lipodepsipeptide Pseudomycin A determined by computer simulations using distance geometry and molecular dynamics from NMR data
Coiro VM, Segre AL, Di Nola A, Paci M, Grottesi A, Veglia G, Ballio A
EUROPEAN JOURNAL OF BIOCHEMISTRY
257 (2): 449-456 OCT 1998

FULL TEXT

Abstract:

Pseudomycin A is a cyclic lipodepsinonapeptide phytotoxin produced by a strain of the plant pathogenic bacterium Pseudomonas syringae. Like other members of this family of bacterial metabolites, it is characterised by a fatty acylated cyclic peptide with mixed chirality and lactonic closure. Several biological activities of Pseudomycin A are lower than those found for some of its congeners, a difference which might depend on the diverse number and distribution of charged residues in the peptide moiety. Hence, it was of interest to investigate its conformation in solution. After the complete interpretation of the two-dimensional NMR spectra, NOE data were obtained and the structure was determined by computer simulations, applying distance geometry and molecular dynamics procedures. The conformation of the large ring of Pseudomycin A in solution includes three rigid structural regions interrupted by three short flexible regions that act as hinges. The overall three-dimensional structure of the cyclic moiety is similar to that of previously studied bioactive lipodepsinonapeptides produced by other pseudomonads.

Author Keywords:

lipodepsinonapeptide, molecular dynamics, NMR, Pseudomonas syringae, Pseudomycin A, solution structure

KeyWords Plus:

NUCLEAR MAGNETIC-RESONANCE, CHANNEL-FORMING ACTIVITIES, PV-SYRINGAE, SYRINGOMYCIN-E, PROTEIN STRUCTURES, PLASMA-MEMBRANE, SYRINGOPEPTINS, SYRINGOTOXIN, BIOSURFACTANT, SPECTROSCOPY

Addresses:

Coiro VM, Univ Rome La Sapienza, Dipartimento Chim, P A Moro 5, I-00185 Rome, Italy
Univ Rome La Sapienza, Dipartimento Chim, I-00185 Rome, Italy
CNR, Ist Strutturist Chim G Giacomello, Rome, Italy
Univ Roma Tor Vergata, Dipartimento Sci & Tecnol Chim, Rome, Italy
Univ Rome La Sapienza, CNR, Dipartimento Sci Biochim A Rossi Fanelli, Rome, Italy
Univ Rome La Sapienza, CNR, Ctr Mol Biol, Rome, Italy