Structural determination of lipid A of the lipopolysaccharide from Pseudomonas reactans. A pathogen of cultivated mushrooms.
The chemical structure of lipid A from the lipopolysaccharide of the mushroom-associated bacterium Pseudomonas reactans, a pathogen of cultivated mushroom, was elucidated by compositional analysis and spectroscopic methods (MALDI-TOF and two-dimensional NMR). The sugar backbone was composed of the beta-(1'-->6)-linked d-glucosamine disaccharide 1-phosphate. The lipid A fraction showed remarkable heterogeneity with respect to the fatty acid and phosphate composition. The major species are hexacylated and pentacylated lipid A, bearing the (R)-3-hydroxydodecanoic acid [C12:0 (3OH)] in amide linkage and a (R)-3-hydroxydecanoic [C10:0 (3OH)] in ester linkage while the secondary fatty acids are present as C12:0 and/or C12:0 (2-OH). A nonstoichiometric phosphate substitution at position C-4' of the distal 2-deoxy-2-amino-glucose was detected. Interestingly, the pentacyl lipid A is lacking a primary fatty acid, namely the C10:0 (3-OH) at position C-3'. The potential biological meaning of this peculiar lipid A is also discussed.
Silipo
Alba
A
Dipartimento di Chimica Organica e Biochimica, Università degli Studi di Napoli Federico II, Napoli, Italy.
Lanzetta
Rosa
R
Garozzo
Domenico
D
Lo Cantore
Pietro
P
Iacobellis
Nicola Sante
NS
Molinaro
Antonio
A
Parrilli
Michelangelo
M
Evidente
Antonio
A
D064753:Ammonium Hydroxide; D002236:Carbohydrate Conformation; D006878:Hydroxides; D008050:Lipid A / Q000737:chemistry* / Q000302:isolation & purification; D011549:Pseudomonas / Q000737:chemistry*
D006878:Hydroxides; D008050:Lipid A; D064753:Ammonium Hydroxide