Structural determination of the Nod factors produced by Rhizobium gallicum bv. gallicum R602.
Rhizobium gallicum is a fast-growing bacterium found in European, Australian and African soils; it was first isolated in France. It is a microsymbiont which is able to nodulate plants of the genus Phaseolus. Rhizobium gallicum bv. gallicum R602 produces four extracellular signal molecules consisting of a linear backbone of N-acetyl glucosamine, bearing on the nonreducing terminal residue an N-methyl group and different N-acyl substituents. The four acyloligosaccharides terminate with a sulfated N-acetylglucosaminitol. This unit may be also acetylated. These structures were determined using carbohydrate and methylation analysis, mass spectrometric analysis and one-dimensional- and two-dimensional-nuclear magnetic resonance experiments. This work establishes the common structure that a lipochito-oligosaccharide must have so that the Rhizobium that produces and excretes it is able to nodulate plants of Phaseolus vulgaris. The substituents common to all the molecules are an N-methyl group and a C(18:1) fatty acid on the nonreducing terminal residue.
Soria-Díaz
M Eugenia
ME
Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Spain.
Rodríguez-Carvajal
Miguel A
MA
Tejero-Mateo
Pilar
P
Espartero
José L
JL
Morón
Belén
B
Sousa
Carolina
C
Megías
Manuel
M
Thomas-Oates
Jane
J
Gil-Serrano
Antonio M
AM
D005944:Glucosamine / Q000031:analogs & derivatives / Q000032:analysis; D008070:Lipopolysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D027805:Phaseolus / Q000382:microbiology*; D012231:Rhizobium / Q000737:chemistry* / Q000378:metabolism
D008070:Lipopolysaccharides; D005944:Glucosamine