OnfD, an AraC -type transcriptional regulator of Rhizobium tropici CIAT 899 involved in Nod factor synthesis and symbiosis

Rhizobium tropici CIAT899 is a tropical symbiont able to nodulate various legumes such as Leucaena, Phaseolus, and Macroptilium. Broad host range of this species is related to its Nod factors wide spectrum. R. tropici contains Nod factors sulphation nod genes, nodHPQ genes, which control nodulation efficiency in Leucaena. To study nodHPQ regulation, we carried out different interposon insertions in its upstream region. One of these generated interruptions, nodI mutant produced nonsulphated Nod factors suggesting a possible dependence of these genes on nodI upstream region. Moreover, analysis results of lacZ transcriptional fusions with these genes in symbiotic plasmid showed dependence of these genes on NodD protein. In order to determine nodHPQ organization, we studied the effect of interposon insertion upstream of each lacZ transcriptional fusion, and the data obtained was used to indicate that nodHPQ belong to the nodABCSUIJ operon. However, comparison between nodP::lacZ β-galactosidase activity in the symbiotic plasmid and in the pHM500 plasmid (containing nodHPQ genes) suggested constitutive expression in free living, and flavonoid inducible expression in symbiotic conditions. Constitutive nodHPQ expression may play a role in bacterial house-keeping metabolism. On the other hand, the transference of R. tropici nodHPQ genes to other rhizobia that do not present sulphated substitutions demonstrated that NodH protein sulphotransference is specific to C6 at the reducing end.Key words: Nod factors, nodHPQ genes, Rhizobium tropici, nod-box.

Download Full-text

The nodD1 gene of Sinorhizobium fredii HH103 Restores Nodulation Capacity on Bean in a Rhizobium tropici CIAT 899 nodD1/nodD2 Mutant, but the Secondary Symbiotic Regulators nolR, nodD2 or syrM Prevent HH103 to Nodulate with This Legume

Microorganisms ◽

10.3390/microorganisms10010139 ◽

2022 ◽

Vol 10 (1) ◽

pp. 139

Author(s):

Francisco Fuentes-Romero ◽

Pilar Navarro-Gómez ◽

Paula Ayala-García ◽

Isamar Moyano-Bravo ◽

Francisco-Javier López-Baena ◽

...

Keyword(s):

Nitrogenase Activity ◽

Lotus Japonicus ◽

Rhizobium Tropici ◽

Sinorhizobium Fredii ◽

Symbiotic Interaction ◽

Model Legume ◽

Nod Factor ◽

Factor Production ◽

Nodulation Capacity ◽

Type 3

Rhizobial NodD proteins and appropriate flavonoids induce rhizobial nodulation gene expression. In this study, we show that the nodD1 gene of Sinorhizobium fredii HH103, but not the nodD2 gene, can restore the nodulation capacity of a double nodD1/nodD2 mutant of Rhizobium tropici CIAT 899 in bean plants (Phaseolus vulgaris). S. fredii HH103 only induces pseudonodules in beans. We have also studied whether the mutation of different symbiotic regulatory genes may affect the symbiotic interaction of HH103 with beans: ttsI (the positive regulator of the symbiotic type 3 protein secretion system), and nodD2, nolR and syrM (all of them controlling the level of Nod factor production). Inactivation of either nodD2, nolR or syrM, but not that of ttsI, affected positively the symbiotic behavior of HH103 with beans, leading to the formation of colonized nodules. Acetylene reduction assays showed certain levels of nitrogenase activity that were higher in the case of the nodD2 and nolR mutants. Similar results have been previously obtained by our group with the model legume Lotus japonicus. Hence, the results obtained in the present work confirm that repression of Nod factor production, provided by either NodD2, NolR or SyrM, prevents HH103 to effectively nodulate several putative host plants.

Download Full-text

Genes Essential for Nod Factor Production and Nodulation Are Located on a Symbiotic Amplicon (AMPRtrCFN299pc60) in Rhizobium tropici

Journal of Bacteriology ◽

10.1128/jb.180.11.2866-2874.1998 ◽

1998 ◽

Vol 180 (11) ◽

pp. 2866-2874 ◽

Cited By ~ 16

Author(s):

Patrick Mavingui ◽

Toon Laeremans ◽

Margarita Flores ◽

David Romero ◽

Esperanza Martínez-Romero ◽

...

Keyword(s):

Insertion Sequence ◽

Gene Dosage ◽

Kanamycin Resistance ◽

Nod Factors ◽

Rhizobium Tropici ◽

Resistance Marker ◽

Nod Factor ◽

Origins Of Replication ◽

Symbiotic Plasmid

ABSTRACT Amplifiable DNA regions (amplicons) have been identified in the genome of Rhizobium etli. Here we report the isolation and molecular characterization of a symbiotic amplicon of Rhizobium tropici. To search for symbiotic amplicons, a cartridge containing a kanamycin resistance marker that responds to gene dosage and conditional origins of replication and transfer was inserted in the nodulation region of the symbiotic plasmid (pSym) of R. tropici CFN299. Derivatives harboring amplifications were selected by increasing the concentration of kanamycin in the cell culture. The amplified DNA region was mobilized into Escherichia coli and then into Agrobacterium tumefaciens. The 60-kb symbiotic amplicon, which we termed AMPRtrCFN299pc60, contains several nodulation and nitrogen fixation genes and is flanked by a novel insertion sequence ISRtr1. Amplification of AMPRtrCFN299pc60 through homologous recombination between ISRtr1 repeats increased the amount of Nod factors. Strikingly, the conjugal transfer of the amplicon into a plasmidlessA. tumefaciens strain confers on the transconjugant the ability to produce R. tropici Nod factors and to nodulatePhaseolus vulgaris, indicating that R. tropicigenes essential for the nodulation process are confined to an ampliable DNA region of the pSym.

Download Full-text

Transfer of the Rhizobium tropici Nod Factor Sulphation Locus to Heterologous Rhizobia: Biochemical and Plant Phenotypic Analysis

Biological Nitrogen Fixation for the 21st Century - Current Plant Science and Biotechnology in Agriculture ◽

10.1007/978-94-011-5159-7_114 ◽

1998 ◽

pp. 245-245

Author(s):

T. Laeremans ◽

J. Mariën ◽

E. Martínez-Romero ◽

J. Vanderleyden

Keyword(s):

Rhizobium Tropici ◽

Phenotypic Analysis ◽

Nod Factor

Download Full-text

Osmotic stress activates nif and fix genes and induces the Rhizobium tropici CIAT 899 Nod factor production via NodD2 by up-regulation of the nodA2 operon and the nodA3 gene

PLoS ONE ◽

10.1371/journal.pone.0213298 ◽

2019 ◽

Vol 14 (3) ◽

pp. e0213298 ◽

Cited By ~ 4

Author(s):

Pablo del Cerro ◽

Manuel Megías ◽

Francisco Javier López-Baena ◽

Antonio Gil-Serrano ◽

Francisco Pérez-Montaño ◽

...

Keyword(s):

Osmotic Stress ◽

Rhizobium Tropici ◽

Nod Factor ◽

Factor Production ◽

Fix Genes

Download Full-text

The non-flavonoid inducible nodA3 and the flavonoid regulated nodA1 genes of Rhizobium tropici CIAT 899 guarantee nod factor production and nodulation of different host legumes

Plant and Soil ◽

10.1007/s11104-019-04073-2 ◽

2019 ◽

Vol 440 (1-2) ◽

pp. 185-200 ◽

Cited By ~ 4

Author(s):

Pablo del Cerro ◽

Paula Ayala-García ◽

Irene Jiménez-Guerrero ◽

Francisco Javier López-Baena ◽

José María Vinardell ◽

...

Keyword(s):

Rhizobium Tropici ◽

Nod Factor ◽

Factor Production

Download Full-text

NrcR, a New Transcriptional Regulator of Rhizobium tropici CIAT 899 Involved in the Legume Root-Nodule Symbiosis

PLoS ONE ◽

10.1371/journal.pone.0154029 ◽

2016 ◽

Vol 11 (4) ◽

pp. e0154029 ◽

Cited By ~ 12

Author(s):

Pablo del Cerro ◽

Amanda A. P. Rolla-Santos ◽

Rocío Valderrama-Fernández ◽

Antonio Gil-Serrano ◽

Ramón A. Bellogín ◽

...

Keyword(s):

Root Nodule ◽

Transcriptional Regulator ◽

Rhizobium Tropici ◽

Root Nodule Symbiosis ◽

Nodule Symbiosis

Download Full-text

Phaseolus vulgaris Recognizes Azorhizobium caulinodans Nod Factors with a Variety of Chemical Substituents

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.1999.12.9.820 ◽

1999 ◽

Vol 12 (9) ◽

pp. 820-824 ◽

Cited By ~ 9

Author(s):

T. Laeremans ◽

C. Snoeck ◽

J. Mariën ◽

C. Verreth ◽

E. Martínez-Romero ◽

...

Keyword(s):

Phaseolus Vulgaris ◽

Host Plant ◽

Wide Spectrum ◽

Nod Factors ◽

Azorhizobium Caulinodans ◽

Rhizobium Tropici ◽

Nod Factor ◽

Mutant Strains

Phaseolus vulgaris is a promiscuous host plant that can be nodulated by many different rhizobia representing a wide spectrum of Nod factors. In this study, we introduced the Rhizobium tropici CFN299 Nod factor sulfation genes nodHPQ into Azorhizobium caulinodans. The A. caulinodans transconjugants produce Nod factors that are mostly if not all sulfated and often with an arabinosyl residue as the reducing end glycosylation. Using A. caulinodans mutant strains, affected in reducing end decorations, and their respective transconjugants in a bean nodulation assay, we demonstrated that bean nodule induction efficiency, in decreasing order, is modulated by the Nod factor reducing end decorations fucose, arabinose or sulfate, and hydrogen.

Download Full-text