A purL mutant of Sinorhizobium fredii HH103 is symbiotically defective and altered in its lipopolysaccharide.
The pleiotropic phenotype of an auxotrophic purL mutant (SVQ295) of Sinorhizobium fredii HH103 has been investigated. SVQ295 forms colonies that are translucent, produce more slime and absorb less Congo red than those of wild-type strain HH103. SVQ295 did not grow in minimal medium unless the culture was supplemented with thiamin and adenine or with thiamin and AICA-riboside (5-aminoimidazole-4-carboxamide 1-beta-D-ribofuranoside), an intermediate of purine biosynthesis. Bacterial cultures supplemented with AICA-riboside or adenine reached the same culture density, although the doubling time of SVQ295 cultures containing AICA-riboside was clearly longer. S. fredii SVQ295 induced pseudonodules on Glycine max and failed to nodulate six different legumes. On Glycyrrhiza uralensis, however, nodules showing nitrogenase activity and containing infected plant cells were formed. SVQ295 showed auto-agglutination when grown in liquid TY medium and its lipopolysaccharide (LPS) electrophoretic profile differed from that of its parental strain HH103-1. In addition, four monoclonal antibodies that recognize the LPS of S. fredii HH103 failed to recognize the LPS produced by SVQ295. In contrast, (1)H-NMR spectra of K-antigen capsular polysaccharides (KPS) produced by SVQ295 and the wild-type strain HH103 were similar. Co-inoculation of soybean plants with SVQ295 and SVQ116 (a nodA mutant derivative of HH103) produced nitrogen-fixing nodules that were only occupied by SVQ116.
Buendía-Clavería
Ana M
AM
Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Apdo 1095, 41080 Sevilla, Spain.
Moussaid
Ahmed
A
Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Apdo 1095, 41080 Sevilla, Spain.
Ollero
F Javier
FJ
Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Apdo 1095, 41080 Sevilla, Spain.
Vinardell
José M
JM
Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Apdo 1095, 41080 Sevilla, Spain.
Torres
Antonio
A
Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Apdo 1095, 41080 Sevilla, Spain.
Moreno
Javier
J
Departamento de Biología Celular, Facultad de Biología, Universidad de Sevilla, Av. Reina Mercedes s/n, 41012 Sevilla, Spain.
Gil-Serrano
Antonio M
AM
Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Apdo 553, 41071 Sevilla, Spain.
Rodríguez-Carvajal
Miguel A
MA
Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Apdo 553, 41071 Sevilla, Spain.
Tejero-Mateo
Pilar
P
Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Apdo 553, 41071 Sevilla, Spain.
Peart
Jan L
JL
Department of Molecular Microbiology, John Innes Centre, Norwich NR4 7UH, UK.
Brewin
Nicholas J
NJ
Department of Molecular Microbiology, John Innes Centre, Norwich NR4 7UH, UK.
Ruiz-Sainz
José E
JE
Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Apdo 1095, 41080 Sevilla, Spain.
D000818:Animals; D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics; D005798:Genes, Bacterial; D008070:Lipopolysaccharides / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D051381:Rats; D020579:Sinorhizobium / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D013025:Glycine max / Q000382:microbiology; D013559:Symbiosis / Q000235:genetics
D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D004269:DNA, Bacterial; D008070:Lipopolysaccharides