Structural characterizations of lipids A by MS/MS of doubly charged ions on a hybrid linear ion trap/orbitrap mass spectrometer.
Here, a new 'one pot' and fast approach is described, based on electrospray ionization (ESI) of negative ions by using a hybrid linear ion trap/orbitrap mass spectrometer (LTQ/orbitrap) for MS and MS/MS analysis. By this method the distribution of the primary and secondary acyl residues of the intact lipid A is inferred by analysis of the ESI spectra measured in positive and negative mode. The analysis of these data allows an unequivocal assignment of the fatty acid distribution. This methodology was successfully tested on two different lipid A with known structures, deriving from the Agrobacterium tumefaciens and Escherichia coli lipopolysaccharides (LPS).
Silipo
Alba
A
Dipartimento di Chimica Organica e Biochimica, Universitá di Napoli Federico II, via Cynthia 4, 80126 Napoli, Italy.
De Castro
Cristina
C
Lanzetta
Rosa
R
Molinaro
Antonio
A
Parrilli
Michelangelo
M
Vago
Giorgio
G
Sturiale
Luisa
L
Messina
Angela
A
Garozzo
Domenico
D
D016960:Agrobacterium tumefaciens / Q000737:chemistry*; D000838:Anions / Q000032:analysis; D004926:Escherichia coli / Q000737:chemistry*; D029968:Escherichia coli Proteins / Q000032:analysis*; D008070:Lipopolysaccharides / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods*
D000838:Anions; D029968:Escherichia coli Proteins; D008070:Lipopolysaccharides