The Experts below are selected from a list of 195 Experts worldwide ranked by ideXlab platform
A. W. B. Johnston - One of the best experts on this subject based on the ideXlab platform.
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the genome of Rhizobium leguminosarum has recognizable core and accessory components
Genome Biology, 2006Co-Authors: Peter J W Young, A. W. B. Johnston, Margaret Wexler, Lisa Crossman, Nicholas R Thomson, Zara Ghazoui, Katherine H Hull, Andrew R J Curson, Jonathan D Todd, Philip S PooleAbstract:Background Rhizobium leguminosarum is an α-proteobacterial N2-fixing symbiont of legumes that has been the subject of more than a thousand publications. Genes for the symbiotic interaction with plants are well studied, but the adaptations that allow survival and growth in the soil environment are poorly understood. We have sequenced the genome of R. leguminosarum biovar viciae strain 3841.
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Structural studies of the Fur protein from Rhizobium leguminosarum
Biochemical Society transactions, 2002Co-Authors: Olatomirin O. Kolade, A. W. B. Johnston, P. Bellini, Margaret Wexler, J. G. Grossmann, Andrew M. HemmingsAbstract:The X-ray crystal structure of the apo-form of the Fur protein from Rhizobium leguminosarum has been solved at 2.7 a resolution. Small-angle X-ray scattering was used to give information on the solution conformation of the protein. The Fur homodimer folds into two domains. The N-terminal domain is formed from the packing of two helix-turn-helix motifs while the C-terminal domain appears primarily to stabilize the dimeric state of the protein.
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A Putative ECF σ Factor Gene, rpoI, Regulates Siderophore Production in Rhizobium leguminosarum
Molecular plant-microbe interactions : MPMI, 1999Co-Authors: Kay H. Yeoman, Alex G. May, Nicola G. Deluca, Daniel B. Stuckey, A. W. B. JohnstonAbstract:A cloned Rhizobium leguminosarum gene, termed rpoI, when transferred to wild-type strains, caused overproduction of the siderophore vicibactin. An rpoI mutant was defective in Fe uptake but was unaffected in symbiotic N2 fixation. The RpoI gene product was similar in sequence to extra-cytoplasmic σ factors of RNA polymerase. Transcription of rpoI was reduced in cells grown in medium that was replete with Fe.
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The Rhizobium leguminosarum biovar viciae nodO gene can enable a nodE mutant of Rhizobium leguminosarum biovar trifolii to nodulate vetch
Microbiology, 1994Co-Authors: Anastassios Economou, A. W. B. Johnston, A. E. Davies, J. A. DownieAbstract:Analysis of the nodulation characteristics of transposon-induced mutants of Rhizobium leguminosarum bv. viciae revealed that nodO and the closely-linked rhi genes contribute to nodulation of peas (Pisum sativum) and the vetch Vicia hirsuta. Although mutation of nodO alone had no significant effect on nodulation of either legume, a double mutant lacking both nodO and nodE nodulated both legumes very poorly. Similarly, a double mutant lacking nodE and either rhiA or rhiB nodulated peas less efficiently than a nodE mutant. Thus, although mutations affecting only the rhi genes normally have no observed effect on nodulation, these genes do appear to contribute to pea nodulation. When transferred to a wild-type strain of Rhizobium leguminosarum bv. trifolii, neither nodO nor the rhi gene region conferred pea or vetch nodulating ability. However, in a nodE mutant of R. I. bv. trifolii, nodO did confer a significant level of vetch nodulating ability, indicating that the secreted NodO protein can play a role in determining legume recognition by R. I. bv. viciae.
Jozef Vanderleyden - One of the best experts on this subject based on the ideXlab platform.
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Cloning and sequence of the Rhizobium leguminosarum biovar phaseoli fixA gene
Biochimica et biophysica acta, 1993Co-Authors: Jan Michiels, Jozef VanderleydenAbstract:We report the identification and cloning of Rhizobium leguminosarum biovar phaseoli fixABCX homologous genes and the complete nucleotide sequence of the fixA gene. The corresponding gene product is highly homologous to the Rhizobium meliloti and AzoRhizobium caulinodans FixA proteins. Putative NtrA- and NifA-binding sites are identified in the fixA promoter region.
Martin Krehenbrink - One of the best experts on this subject based on the ideXlab platform.
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identification of protein secretion systems and novel secreted proteins in Rhizobium leguminosarum bv viciae
BMC Genomics, 2008Co-Authors: Martin Krehenbrink, Allan J DownieAbstract:Background Proteins secreted by bacteria play an important role in infection of eukaryotic hosts. Rhizobia infect the roots of leguminous plants and establish a mutually beneficial symbiosis. Proteins secreted during the infection process by some rhizobial strains can influence infection and modify the plant defence signalling pathways. The aim of this study was to systematically analyse protein secretion in the recently sequenced strain Rhizobium leguminosarum bv. viciae 3841.
Dietrich Werner - One of the best experts on this subject based on the ideXlab platform.
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Application of subtraction hybridization for the development of a Rhizobium leguminosarum biovar phaseoli and Rhizobium tropici group-specific DNA probe
FEMS Microbiology Ecology, 1993Co-Authors: Wolfgang R. Streit, Anthony J. Bjourson, J. E. Cooper, Dietrich WernerAbstract:A combined subtraction hybridization and polymerase chain reaction/amplification technique was used to develop a DNA probe which was specific for the Rhizobium leguminosarum biovar phaseoli and the Rhizobium tropici group. Total genomic DNA preparations from Rhizobium leguminosarum biovar viciae, Rhizobium leguminosarum biovar trifolii, Rhizobium sp., Agrobacterium tumefaciens, Rhizobium fredii, BradyRhizobium japonicum, BradyRhizobium ssp. and Rhizobium meliloti were pooled and used as subtracter DNA against total genomic DNA from the Rhizobium leguminosarum biovar phaseolo strain KIM5s. Only one round of subtraction hybridization at 65°C was necessary to remove all cross-hybridizing sequences. Dot blot hybridizations with total genomic DNA of the eight subtracter organisms and 29 bacteria of different groups confirmed the high specificity of the isolated DNA sequences. Dot blot hybridizations and total genomic DNA from ten different R. leguminosarum biovar phaseoli and R. tropici strains resulted in strong hybridization signals for all strains tested. The DNA probe for the R. tropici and R. leguminosarum biovar phaseoli group was used for dot blot hybridization with DNA extracts from three tropical and one boreal soil. When correlated with data from Most Probable Number analyses the probe was capable of detecting as low as 3 × 104 homologous indigenous rhizobia per g soil. The technique offers great benefits for the development of DNA probes for monitoring bacterial populations in environmental samples.
Philip S Poole - One of the best experts on this subject based on the ideXlab platform.
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Arabinose and protocatechuate catabolism genes are important for growth of Rhizobium leguminosarum biovar viciae in the pea rhizosphere
Plant and Soil, 2015Co-Authors: Paula García-fraile, Philip S Poole, Jonathan C. Seaman, Ramakrishnan Karunakaran, Anne Edwards, J. Allan DownieAbstract:Background and aims To form nitrogen-fixing nodules on pea roots, Rhizobium leguminosarum biovar viciae must be competitive in the rhizosphere. Our aim was to identify genes important for rhizosphere fitness.
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the pts ntr system globally regulates atp dependent transporters in Rhizobium leguminosarum
Molecular Microbiology, 2012Co-Authors: Jurgen Prell, J. A. Downie, Ramakrishnan Karunakaran, Geraldine Mulley, F Haufe, J P White, Alan G Williams, Philip S PooleAbstract:Ntr system in Rhizobium leguminosarum strain Rlv3841 caused a pleiotropic phenotype as observed with many bacte- ria. The mutant formed dry colonies and grew poorly on organic nitrogen or dicarboxylates. Most strikingly the ptsP mutant had low activity of a broad range of ATP-dependent ABC transporters. This lack of activa- tion, which occurred post-translationally, may explain many of the pleiotropic effects. In contrast proton- coupledtransportsystemswerenotinhibitedinaptsP mutant.RegulationbyPtsPalsoinvolvestwocopiesof ptsN that code for EIIA Ntr , resulting in a phosphoryla- tioncascade.AsinEscherichiacoli,theRlv3841PTS Ntr
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the genome of Rhizobium leguminosarum has recognizable core and accessory components
Genome Biology, 2006Co-Authors: Peter J W Young, A. W. B. Johnston, Margaret Wexler, Lisa Crossman, Nicholas R Thomson, Zara Ghazoui, Katherine H Hull, Andrew R J Curson, Jonathan D Todd, Philip S PooleAbstract:Background Rhizobium leguminosarum is an α-proteobacterial N2-fixing symbiont of legumes that has been the subject of more than a thousand publications. Genes for the symbiotic interaction with plants are well studied, but the adaptations that allow survival and growth in the soil environment are poorly understood. We have sequenced the genome of R. leguminosarum biovar viciae strain 3841.