Lipid A structure of Pseudoalteromonas haloplanktis TAC 125: use of electrospray ionization tandem mass spectrometry for the determination of fatty acid distribution.
The use of electrospray Ionization (ESI) tandem mass spectrometry (MS/MS) for the structural determination of the lipid A components of the psychrophilic bacterium Pseudoalteromonas haloplanktis TAC 125 is reported. The lipid A contains the classical bisphosphorylated beta-(1' --> 6)-linked D-glucosamine disaccharide with 3-hydroxydodecanoyl residues (12 : 0 (3-OH)) linked both as esters and amides to 2', 3' (distal glucosamine) and 2, 3 positions (proximal glucosamine) of the sugar backbone. The hydroxyl of 12 : 0 (3-OH) fatty acid linked at the 3' position is esterified by a dodecanoyl residue (12 : 0). In addition to the pentaacyl component, a minor tetraacyl lipid A, lacking the acyl residue at position 3, was also found in the lipid A fraction. The advantage of this MS technique for the investigation of the intra-ring fragmentation, which is useful for the determination of fatty acyl residue distribution on each glucosamine unit, is emphasized.
Dipartimento di Chimica Organica e Biochimica, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, via Cynthia 4, 80126 Naples, Italy. corsaro@unina.it
Maria Michela
MM
Corsaro
Fabrizio Dal
FD
Piaz
Rosa
R
Lanzetta
Michelangelo
M
Parrilli
D005227:Fatty Acids / Q000032:analysis*; D005944:Glucosamine / Q000032:analysis; D006090:Gram-Negative Bacteria / Q000737:chemistry*; D008050:Lipid A / Q000737:chemistry* / Q000302:isolation & purification; D008070:Lipopolysaccharides / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D005227:Fatty Acids; D008050:Lipid A; D008070:Lipopolysaccharides; D005944:Glucosamine