scholarly journals Mutation in GDP-Fucose Synthesis Genes of Sinorhizobium fredii Alters Nod Factors and Significantly Decreases Competitiveness to Nodulate Soybeans

1999 ◽  
Vol 12 (3) ◽  
pp. 207-217 ◽  
Author(s):  
Youssef Lamrabet ◽  
Ramón A. Bellogín ◽  
Teresa Cubo ◽  
Rosario Espuny ◽  
Antonio Gil ◽  
...  
Keyword(s):  
Fatty Acyl ◽  
Side Chain ◽  
Broad Host Range ◽  
Nod Factors ◽  
Nucleotide Sugar ◽  
Sinorhizobium Fredii ◽  
Hindiii Fragment ◽  
Transposon Insertion ◽  
Nodulation Rate ◽  
Soybean Nodulation

We mutagenized Sinorhizobium fredii HH103-1 with Tn5- B20 and screened about 2,000 colonies for increased β-galactosidase activity in the presence of the flavonoid naringenin. One mutant, designated SVQ287, produces lipochitooligosaccharide Nod factors (LCOs) that differ from those of the parental strain. The nonreducing N-acetylglucosamine residues of all of the LCOs of mutant SVQ287 lack fucose and 2-O-methylfucose substituents. In addition, SVQ287 synthesizes an LCO with an unusually long, C20:1 fatty acyl side chain. The transposon insertion of mutant SVQ287 lies within a 1.1-kb HindIII fragment. This and an adjacent 2.4-kb HindIII fragment were sequenced. The sequence contains the 3′ end of noeK, nodZ, and noeL (the gene interrupted by Tn5-B20), and the 5′ end of nolK, all in the same orientation. Although each of these genes has a similarly oriented counterpart on the symbiosis plasmid of the broad-host-range Rhizobium sp. strain NGR234, there are significant differences in the noeK/nodZ intergenic region. Based on amino acid sequence homology, noeL encodes GDP-D-mannose dehydratase, an enzyme involved in the synthesis of GDP-Lfucose, and nolK encodes a NAD-dependent nucleotide sugar epimerase/dehydrogenase. We show that expression of the noeL gene is under the control of NodD1 in S. fredii and is most probably mediated by the nod box that precedes nodZ. Transposon insertion into noeL has two impacts on symbiosis with Williams soybean: nodulation rate is reduced slightly and competitiveness for nodulation is decreased significantly. Mutant SVQ287 retains its ability to form nitrogen-fixing nodules on other legumes, but final nodule number is attenuated on Cajanus cajan.

Alfalfa nodulation by Sinorhizobium fredii does not require sulfated Nod-factors

2003 ◽  
Vol 30 (12) ◽  
pp. 1219 ◽  
Author(s):  
Sadaf Noreen ◽  
Helmi R. M. Schlaman ◽  
Ramón A. Bellogín ◽  
Ana M. Buendía-Clavería ◽  
MaríaRosario Espuny ◽  
...  
Keyword(s):  
Acyl Chain ◽  
Fatty Acyl ◽  
Fatty Acyl Chain ◽  
Insertion Mutation ◽  
Rhizobium Strain ◽  
Nod Factors ◽  
Sinorhizobium Fredii ◽  
Nod Factor ◽  
Nodulation Capacity ◽  
Soybean Nodulation

Rhizobium strain 042B(s) is able to nodulate both soybean and alfalfa cultivars. We have demonstrated, by mass spectrometry, that the nodulation (Nod) factors produced by this strain are characteristic of those produced by Sinorhizobium fredii, which typically nodulates soybean; they have 3–5 N-acetylglucosamine (GlcNAc) residues, a mono-unsaturated or saturated C16, C18 or C20 fatty-acyl chain, and a (methyl)fucosyl residue on C6 of the reducing-terminal GlcNAc. In order to study Rhizobium strain 042B(s) and its nodulation behaviour further, we introduced an insertion mutation in the noeL gene, which is responsible for the presence of the (methyl)fucose residue on the reducing terminal GlcNAc of the Nod-factors, yielding mutant strain SVQ523. A plasmid (pHM500) carrying nodH, nodP and nodQ, the genes involved in sulfation of Nod-factors on C6 of the reducing-terminal GlcNAc, was introduced into SVQ523, generating SVQ523.pHM500. As expected, strain SVQ523 produces unfucosylated Nod-factors, while SVQ523.pHM500 produces both unfucosylated and unfucosylated sulfated Nod-factors. Plant tests showed that soybean nodulation was reduced if the inoculant (SVQ523.pHM500) produced sulfated Nod-factors. In the Asiatic alfalfa cultivar Baoding, SVQ523 (absence of a substitution at C6) failed to nodulate, but both 042B(s) (fucosyl at C6) and SVQ523.pHM500 (sulfate at C6) formed nodules. In contrast, SVQ523 showed enhanced nodulation capacity with the western alfalfa cultivars ORCA and ARC. These results indicate that Nod-factor sulfation is not a requisite for S. fredii to nodulate alfalfa.

scholarly journals Sinorhizobium fredii HH103 Invades Lotus burttii by Crack Entry in a Nod Factor–and Surface Polysaccharide–Dependent Manner

2016 ◽  
Vol 29 (12) ◽  
pp. 925-937 ◽  
Author(s):  
Sebastián Acosta-Jurado ◽  
Dulce-Nombre Rodríguez-Navarro ◽  
Yasuyuki Kawaharada ◽  
Juan Fernández Perea ◽  
Antonio Gil-Serrano ◽  
...  
Keyword(s):  
Root Hairs ◽  
Broad Host Range ◽  
Capsular Polysaccharides ◽  
Dependent Manner ◽  
Nod Factors ◽  
Sinorhizobium Fredii ◽  
Nod Factor ◽  
Mesorhizobium Loti ◽  
Infection Threads ◽  
Surface Polysaccharide

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-Rifr invade 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-Rifr nodA 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-Rifr mutants 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-Rifr fla mutants nodulated L. burttii. None of the S. fredii HH103-Rifr surface-polysaccharide mutants gained effective nodulation with L. japonicus.

scholarly journals Sinorhizobium fredii HH103 Has a Truncated nolO Gene Due to a -1 Frameshift Mutation That Is Conserved Among Other Geographically Distant S. fredii Strains

2002 ◽  
Vol 15 (2) ◽  
pp. 150-159 ◽  
Author(s):  
Nuria Madinabeitia ◽  
Ramón A. Bellogín ◽  
Ana M. Buendía-Clavería ◽  
María Camacho ◽  
Teresa Cubo ◽  
...  
Keyword(s):  
Frameshift Mutation ◽  
Nod Factors ◽  
Coding Region ◽  
Sinorhizobium Fredii ◽  
Transposon Insertion ◽  
Base Pair Deletion ◽  
Mutant Derivative ◽  
Type Gene ◽  
Polymerase Chain Reaction Primers ◽  
Rhizobium Sp

Strain SVQ121 is a mutant derivative of Sinorhizobium fredii HH103 carrying a transposon Tn5-lacZ insertion into the nolO-coding region. Sequence analysis of the wild-type gene revealed that it is homologous to that of Rhizobium sp. NGR234, which is involved in the 3 (or 4)-O-carbamoylation of the nonreducing terminus of Nod factors. Downstream of nolO, as in Rhizobium sp. NGR234, the noeI gene responsible for methylation of the fucose moiety of Nod factors was found. SVQ121 Nod factors showed lower levels of methylation into the fucosyl residue than those of HH103, suggesting a polar effect of the transposon insertion into nolO over the noeI gene. A noeI HH103 mutant was constructed. This mutant, SVQ503, produced Nod factors devoid of methyl groups, confirming that the S. fredii noeI gene is functional. Neither the nolO nor the noeI mutation affected the ability of HH103 to nodulate several host plants, but both mutations reduced competitiveness to nodulate soybean. The Nod factors produced by strain HH103, like those of other S. fredii isolates, lack carbamoyl residues. By using specific polymerase chain reaction primers, we sequenced the nolO gene of S. fredii strains USDA192, USDA193, USDA257, and 042B(s). All the analyzed strains showed the same -1 frameshift mutation that is present in the HH103 nolO-coding region. From these results, it is concluded that, regardless of their geographical origin, S. fredii strains carry the nolO-coding region but that it is truncated by the same base-pair deletion.

scholarly journals Complete Genome Sequence of the Broad-Host-Range Strain Sinorhizobium fredii USDA257

2012 ◽  
Vol 194 (16) ◽  
pp. 4483-4483 ◽  
Author(s):  
J. Schuldes ◽  
M. Rodriguez Orbegoso ◽  
C. Schmeisser ◽  
H. B. Krishnan ◽  
R. Daniel ◽  
...  
Keyword(s):  
Host Range ◽  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Broad Host Range ◽  
Sinorhizobium Fredii

scholarly journals The Sinorhizobium fredii HH103 MucR1 Global Regulator Is Connected With the nod Regulon and Is Required for Efficient Symbiosis With Lotus burttii and Glycine max cv. Williams

2016 ◽  
Vol 29 (9) ◽  
pp. 700-712 ◽  
Author(s):  
Sebastián Acosta-Jurado ◽  
Cynthia Alias-Villegas ◽  
Pilar Navarro-Gómez ◽  
Susanne Zehner ◽  
Piedad del Socorro Murdoch ◽  
...  
Keyword(s):  
Glycine Max ◽  
Cell Aggregation ◽  
Broad Host Range ◽  
Rna Seq ◽  
Free Living ◽  
Sinorhizobium Fredii ◽  
Global Regulators ◽  
Enhanced Production ◽  
Free Living Conditions

Sinorhizobium fredii HH103 is a rhizobial strain showing a broad host range of nodulation. In addition to the induction of bacterial nodulation genes, transition from a free-living to a symbiotic state requires complex genetic expression changes with the participation of global regulators. We have analyzed the role of the zinc-finger transcriptional regulator MucR1 from S. fredii HH103 under both free-living conditions and symbiosis with two HH103 host plants, Glycine max and Lotus burttii. Inactivation of HH103 mucR1 led to a severe decrease in exopolysaccharide (EPS) biosynthesis but enhanced production of external cyclic glucans (CG). This mutant also showed increased cell aggregation capacity as well as a drastic reduction in nitrogen-fixation capacity with G. max and L. burttii. However, in these two legumes, the number of nodules induced by the mucR1 mutant was significantly increased and decreased, respectively, with respect to the wild-type strain, indicating that MucR1 can differently affect nodulation depending on the host plant. RNA-Seq analysis carried out in the absence and the presence of flavonoids showed that MucR1 controls the expression of hundreds of genes (including some related to EPS production and CG transport), some of them being related to the nod regulon.

scholarly journals Expression of a Serratia marcescens Chitinase Gene in Sinorhizobium fredii USDA191 and Sinorhizobium meliloti RCR2011 Impedes Soybean and Alfalfa Nodulation

1999 ◽  
Vol 12 (8) ◽  
pp. 748-751 ◽  
Author(s):  
Hari B. Krishnan ◽  
Kil Yong Kim ◽  
Ammulu Hari Krishnan
Keyword(s):  
Serratia Marcescens ◽  
Sinorhizobium Meliloti ◽  
Wild Type Strain ◽  
Nodule Formation ◽  
Broad Host Range ◽  
Sinorhizobium Fredii ◽  
Gene Encoding ◽  
Range Vector ◽  
Layer Chromatography ◽  
Hydrolysis Of

A gene encoding chitinase from Serratia marcescens BJL200 was cloned into a broad-host-range vector (pRK415) and mobilized into Sinorhizobium fredii USDA191. Chitinolytic activity was detected in S. fredii USDA191 transconjugants that carried the S. marcescens chiB gene. Chitinase-producing S. fredii USDA191 formed nodules on soybean cultivar McCall. However, there was a delay in nodule formation and a marked decrease in the total number of nodules formed by the chitinase-producing S. fredii in comparison with the wild-type strain. Expression of chitinase in S. meliloti RCR2011 also impeded alfalfa nodulation. Thin-layer chromatography of 14C-labeled Nod factors from chitinase-producing S. fredii USDA191 revealed hydrolysis of lipochitooligosaccharides.

scholarly journals The Sinorhizobium (Ensifer) fredii HH103 Nodulation Outer Protein NopI Is a Determinant for Efficient Nodulation of Soybean and Cowpea Plants

2016 ◽  
Vol 83 (5) ◽  
Author(s):  
Irene Jiménez-Guerrero ◽  
Francisco Pérez-Montaño ◽  
Carlos Medina ◽  
Francisco Javier Ollero ◽  
Francisco Javier López-Baena
Keyword(s):  
Adenylate Cyclase ◽  
Host Cell ◽  
Host Range ◽  
Pathogenic Bacteria ◽  
Defense Responses ◽  
Host Cells ◽  
Broad Host Range ◽  
Sinorhizobium Fredii ◽  
Symbiotic Efficiency ◽  
Content Type

ABSTRACT The type III secretion system (T3SS) is a specialized secretion apparatus that is commonly used by many plant and animal pathogenic bacteria to deliver proteins, termed effectors, to the interior of the host cells. These effectors suppress host defenses and interfere with signal transduction pathways to promote infection. Some rhizobial strains possess a functional T3SS, which is involved in the suppression of host defense responses, host range determination, and symbiotic efficiency. The analysis of the genome of the broad-host-range rhizobial strain Sinorhizobium fredii HH103 identified eight genes that code for putative T3SS effectors. Three of these effectors, NopL, NopP, and NopI, are Rhizobium specific. In this work, we demonstrate that NopI, whose amino acid sequence shows a certain similarity with NopP, is secreted through the S. fredii HH103 T3SS in response to flavonoids. We also determined that NopL can be considered an effector since it is directly secreted to the interior of the host cell as demonstrated by adenylate cyclase assays. Finally, the symbiotic phenotype of single, double, and triple nopI, nopL, and nopP mutants in soybean and cowpea was assayed, showing that NopI plays an important role in determining the number of nodules formed in both legumes and that the absence of both NopL and NopP is highly detrimental for symbiosis. IMPORTANCE The paper is focused on three Rhizobium-specific T3SS effectors of Sinorhizobium fredii HH103, NopL, NopP, and NopI. We demonstrate that S. fredii HH103 is able to secrete through the T3SS in response to flavonoids the nodulation outer protein NopI. Additionally, we determined that NopL can be considered an effector since it is secreted to the interior of the host cell as demonstrated by adenylate cyclase assays. Finally, nodulation assays of soybean and cowpea indicated that NopI is important for the determination of the number of nodules formed and that the absence of both NopL and NopP negatively affected nodulation.

scholarly journals Rhizobium sp. BR816 Produces a Complex Mixture of Known and Novel Lipochitooligosaccharide Molecules

2001 ◽  
Vol 14 (5) ◽  
pp. 678-684 ◽  
Author(s):  
Carla Snoeck ◽  
Ellen Luyten ◽  
Véréna Poinsot ◽  
Arlette Savagnac ◽  
Jos Vanderleyden ◽  
...  
Keyword(s):  
Complex Mixture ◽  
Fatty Acyl ◽  
Nodule Development ◽  
Signal Molecules ◽  
Plant Responses ◽  
Broad Host Range ◽  
Terminal Residue ◽  
Acetyl Group ◽  
Acyl Chains ◽  
Rhizobium Sp

Rhizobial lipochitooligosaccharide (LCO) signal molecules induce various plant responses, leading to nodule development. We report here the LCO structures of the broad-host range strain Rhizobium sp. BR816. The LCOs produced are all pentamers, carrying common C18:1 or C18:0 fatty acyl chains, N-methylated and C-6 carbamoylated on the nonreducing terminal N-acetylglucosamine and sulfated on the reducing/terminal residue. A second acetyl group can be present on the penultimate N-acetylglu-cosamine from the nonreducing terminus. Two novel characteristics were observed: the reducing/terminal residue can be a glucosaminitol (open structure) and the degree of acetylation of this glucosaminitol or of the reducing residue can vary.

Regulation of Nod factor sulphation genes in Rhizobium tropici CIAT899

2001 ◽  
Vol 47 (6) ◽  
pp. 574-579 ◽  
Author(s):  
Hamid Manyani ◽  
Carolina Sousa ◽  
María-Eugenia Soria Díaz ◽  
Antonio Gil-Serrano ◽  
Manuel Megías
Keyword(s):  
Wide Spectrum ◽  
Constitutive Expression ◽  
Upstream Region ◽  
Broad Host Range ◽  
Nod Factors ◽  
Rhizobium Tropici ◽  
Free Living ◽  
Nod Factor ◽  
Symbiotic Plasmid ◽  
Transcriptional Fusions

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.

scholarly journals Extracellular Proteins Involved in Soybean Cultivar-Specific Nodulation Are Associated with Pilus-Like Surface Appendages and Exported by a Type III Protein Secretion System in Sinorhizobium fredii USDA257

2003 ◽  
Vol 16 (7) ◽  
pp. 617-625 ◽  
Author(s):  
Hari B. Krishnan ◽  
Julio Lorio ◽  
Won Seok Kim ◽  
Guoqiao Jiang ◽  
Kil Yong Kim ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Symbiotic Bacterium ◽  
Secretion System ◽  
Extracellular Proteins ◽  
Effector Proteins ◽  
Broad Host Range ◽  
Sinorhizobium Fredii ◽  
Type Iii ◽  
Conserved Genes ◽  
Type Iii Protein Secretion

Several gram-negative plant and animal pathogenic bacteria have evolved a type III secretion system (TTSS) to deliver effector proteins directly into the host cell cytosol. Sinorhizobium fredii USDA257, a symbiont of soybean and many other legumes, secretes proteins called Nops (nodulation outer proteins) into the extracellular environment upon flavonoid induction. Mutation analysis and the nucleotide sequence of a 31.2-kb symbiosis (sym) plasmid DNA region of USDA257 revealed the existence of a TTSS locus in this symbiotic bacterium. This locus includes rhc (rhizobia conserved) genes that encode components of a TTSS and proteins that are secreted into the environment (Nops). The genomic organization of the TTSS locus of USDA257 is remarkably similar to that of another broad-host range symbiont, Rhizobium sp. strain NGR234. Flavonoids that activate the transcription of the nod genes of USDA257 also stimulate the production of novel filamentous appendages known as pili. Electron microscope examination of isolated pili reveals needle-like filaments of 6 to 8 nm in diameter. The production of the pili is dependent on a functional nodD1 and the presence of a nod gene-inducing compound. Mutations in several of the TTSS genes negate the ability of USDA257 to elaborate pili. Western blot analysis using antibodies raised against purified NopX, Nop38, and Nop7 reveals that these proteins were associated with the pili. Mutations in rhcN, rhcJ, rhcC, and ttsI alter the ability of USDA257 to form nodules on Glycine max and Macroptilium atropurpureum.

Sign in / Sign up

Export Citation Format

Share Document