Sinorhizobium fredii HH103 Invades Lotus burttii by Crack Entry in a Nod Factor-and Surface Polysaccharide-Dependent Manner.
Sinorhizobium fredii HH103-Rifr, a broad host range rhizobial strain, induces nitrogen-fixing nodules in Lotus burttii but ineffective nodules in L. japonicus. Confocal microscopy studies showed that Mesorhizobium loti MAFF303099 and S. fredii HH103-Rifrinvade L. burttii roots through infection threads or epidermal cracks, respectively. Infection threads in root hairs were not observed in L. burttii plants inoculated with S. fredii HH103-Rifr. A S. fredii HH103-RifrnodA mutant failed to nodulate L. burttii, demonstrating that Nod factors are strictly necessary for this crack-entry mode, and a noeL mutant was also severely impaired in L. burttii nodulation, indicating that the presence of fucosyl residues in the Nod factor is symbiotically relevant. However, significant symbiotic impacts due to the absence of methylation or to acetylation of the fucosyl residue were not detected. In contrast S. fredii HH103-Rifrmutants showing lipopolysaccharide alterations had reduced symbiotic capacity, while mutants affected in production of either exopolysaccharides, capsular polysaccharides, or both were not impaired in nodulation. Mutants unable to produce cyclic glucans and purine or pyrimidine auxotrophic mutants formed ineffective nodules with L. burttii. Flagellin-dependent bacterial mobility was not required for crack infection, since HH103-Rifrfla mutants nodulated L. burttii. None of the S. fredii HH103-Rifrsurface-polysaccharide mutants gained effective nodulation with L. japonicus.
1 Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Avda. Reina Mercedes 6, C.P. 41012, Sevilla, Spain.
Sebastián
S
Acosta-Jurado
2 IFAPA, Centro Las Torres-Tomejil, Apartado Oficial 41200, Alcalá del Río, Sevilla, Spain.
Dulce-Nombre
DN
Rodríguez-Navarro
3 Department of Molecular Biology and Genetics, Centre for Carbohydrate Recognition and Signalling, Aarhus University, Gustav Wieds Vej 10, Aarhus C DK-8000, Denmark; and.
Yasuyuki
Y
Kawaharada
2 IFAPA, Centro Las Torres-Tomejil, Apartado Oficial 41200, Alcalá del Río, Sevilla, Spain.
Juan Fernández
JF
Perea
4 Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Calle Profesor García González 1, C. P. 41012, Sevilla, Spain.
Antonio
A
Gil-Serrano
3 Department of Molecular Biology and Genetics, Centre for Carbohydrate Recognition and Signalling, Aarhus University, Gustav Wieds Vej 10, Aarhus C DK-8000, Denmark; and.
Haojie
H
Jin
1 Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Avda. Reina Mercedes 6, C.P. 41012, Sevilla, Spain.
Qi
Q
An
4 Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Calle Profesor García González 1, C. P. 41012, Sevilla, Spain.
Miguel A
MA
Rodríguez-Carvajal
3 Department of Molecular Biology and Genetics, Centre for Carbohydrate Recognition and Signalling, Aarhus University, Gustav Wieds Vej 10, Aarhus C DK-8000, Denmark; and.
Stig U
SU
Andersen
3 Department of Molecular Biology and Genetics, Centre for Carbohydrate Recognition and Signalling, Aarhus University, Gustav Wieds Vej 10, Aarhus C DK-8000, Denmark; and.
Niels
N
Sandal
3 Department of Molecular Biology and Genetics, Centre for Carbohydrate Recognition and Signalling, Aarhus University, Gustav Wieds Vej 10, Aarhus C DK-8000, Denmark; and.
Jens
J
Stougaard
1 Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Avda. Reina Mercedes 6, C.P. 41012, Sevilla, Spain.
José-María
JM
Vinardell
1 Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Avda. Reina Mercedes 6, C.P. 41012, Sevilla, Spain.
José E
JE
Ruiz-Sainz
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D058507:Host Specificity; D000070116:Lotus / Q000166:cytology / Q000382:microbiology* / Q000502:physiology; D009154:Mutation; D010641:Phenotype; D055170:Plant Root Nodulation; D018517:Plant Roots / Q000166:cytology / Q000382:microbiology / Q000502:physiology; D011135:Polysaccharides, Bacterial / Q000737:chemistry / Q000378:metabolism*; D011687:Purines / Q000378:metabolism; D011743:Pyrimidines / Q000378:metabolism; D042181:Sinorhizobium fredii / Q000166:cytology / Q000235:genetics / Q000502:physiology*; D013559:Symbiosis
D001426:Bacterial Proteins; D011135:Polysaccharides, Bacterial; D011687:Purines; D011743:Pyrimidines; C030986:pyrimidine; C030985:purine