| molecular characterization and regulation of the rhizosphere-expressed genes rhiabcr that can influence nodulation by rhizobium leguminosarum biovar viciae. | a group of four rhi (rhizosphere-expressed) genes from the symbiotic plasmid of rhizobium leguminosarum biovar viciae has been characterized. although mutation of the rhi genes does not normally affect nodulation, in the absence of the closely linked nodulation genes nodfel, mutations in the rhi genes can influence the nodulation of the vetch vicia hirsuta. the dna sequence of the rhi gene region reveals four large open reading frames, three of them constituting an operon (rhiabc) transcribed co ... | 1992 | 1597418 |
| suppression of nodulation gene expression in bacteroids of rhizobium leguminosarum biovar viciae. | the expression of nod genes of rhizobium leguminosarum bv. viciae in nodules of pisum sativum was investigated at both the translational and transcriptional levels. by using immunoblots, it was found that the levels of noda, nodi, node, and nodo proteins were reduced at least 14-fold in bacteriods compared with cultured cells, whereas nodd protein was reduced only 3-fold. northern (rna) blot hybridization, rnase protection assays, and in situ rna hybridization together showed that, except for th ... | 1991 | 1712355 |
| either of two nod gene loci can complement the nodulation defect of a nod deletion mutant of rhizobium leguminosarum bv viciae. | a deletion mutant of rhizobium leguminosarum biovar viciae lacking the host-specific nodulation (nod) gene region (nodfel nodmnt and nodo) but retaining the other nod genes (nodd nodabcij) was unable to nodulate peas or vicia hirsuta, although it did induce root hair deformation. the mutant appeared to be blocked in its ability to induce infection threads and could be rescued for nodulation of v. hirsuta in mixed inoculation experiments with an exopolysaccharide deficient mutant (which is also n ... | 1990 | 2233683 |
| genes involved in lipopolysaccharide production and symbiosis are clustered on the chromosome of rhizobium leguminosarum biovar viciae vf39. | four mutants of rhizobium leguminosarum biovar viciae vf39 altered in lipopolysaccharide (lps) synthesis were isolated upon random tn5 mutagenesis. these mutants produced matt colonies on ty medium and showed autoagglutination and loss of motility. on sodium dodecyl sulfate-polyacrylamide gels, they lacked a slow-migrating carbohydrate band, corresponding to the complete lps (lpsi). all four mutants formed small white nodules on vicia hirsuta. these nodules were infected but showed no nitrogen-f ... | 1989 | 2553672 |
| localization and symbiotic function of a region on the rhizobium leguminosarum sym plasmid prl1ji responsible for a secreted, flavonoid-inducible 50-kilodalton protein. | a previously described (r. a. de maagd, c. a. wijffelman, e. pees, and b. j. j. lugtenberg, j. bacteriol. 170:4424-4427, 1988) sym plasmid-dependent, naringenin-inducible 50-kilodalton protein of rhizobium leguminosarum biovar viciae is further characterized in this paper. the protein was overproduced by constructing a strain containing multiple copies of the r. meliloti nodd gene, which facilitated its purification. an antiserum was used to screen tn5 insertion mutants located in the prl1ji reg ... | 1989 | 2644226 |
| analysis of pss genes of rhizobium leguminosarum required for exopolysaccharide synthesis and nodulation of peas: their primary structure and their interaction with psi and other nodulation genes. | strains of rhizobium leguminosarum (r.l.) biovar viciae containing pss mutations fail to make the acidic exopolysaccharides (eps) and are unable to nodulate peas. it was found that they also failed to nodulate vicia hirsuta, another host of this biovar. when peas were co-inoculated with pss mutant derivatives of a strain of r.l. by viciae containing a sym plasmid plus a cured strain lacking a sym plasmid (and which is thus nod-, but for different reasons) but which makes the acidic eps, normal n ... | 1988 | 2851702 |
| nodulation inhibition by rhizobium leguminosarum multicopy nodabc genes and analysis of early stages of plant infection. | during analysis of early events in the infection and nodulation of vicia hirsuta roots inoculated with normal and mutant strains of rhizobium leguminosarum and strains containing cloned nodulation (nod) genes, a number of novel observations were made. (i) alternating zones of curled and straight root hairs were seen on roots of v. hirsuta inoculated with the wild-type strain of r. leguminosarum. this phasing of root hair curling was not seen if plants were grown under continuous light or continu ... | 1986 | 3009408 |
| characterization of the rhizobium leguminosarum genes nodlmn involved in efficient host-specific nodulation. | three nodulation genes, nodl, nodm and nodn, were isolated from rhizobium leguminosarum and their dna sequences were determined. the three genes are in the same orientation as the previously described nodfe genes and the predicted molecular weights of their products are 20,105 (nodl), 65,795 (nodm) and 18,031 (nodn). analysis of gene regulation using operon fusions showed that nodl, nodm and nodn are induced in response to flavanone molecules and that this induction is nodd-dependent. in additio ... | 1988 | 3132583 |
| rhizobium leguminosarum genes involved in early stages of nodulation. | nodulation genes from rhizobium leguminosarum have been subcloned and transferred to a strain of r. phaseoli with its symbiotic plasmid deleted (and therefore its nodulation and nitrogen fixation genes). normal infection and nodule development occurred when these strains were added to the roots of pisum sativum (peas) and vicia hirsuta. the pea nodules were examined by electron microscopy; bacteroid forms were seen surrounded by peribacteroid membranes and using immuno-gold labelling it was show ... | 1985 | 3867677 |
| a 200 bp region of the pea enod12 promoter is sufficient for nodule-specific and nod factor induced expression. | enod12 is one of the first nodulin genes expressed upon inoculation with rhizobium and also purified nod factors are able to induce enod12 expression. the enod12 gene family in pea (pisum sativum) has two members. a cdna clone representing psenod12a [26] and a psenod12b genomic clone [7] have been previously described. the isolation and characterization of a psenod12a genomic clone is presented in this paper. by using a vicia hirsuta-agrobacterium rhizogenes transformation system it is shown tha ... | 1995 | 7548827 |
| the promoter of the vicia faba l. vfenod-grp3 gene encoding a glycine-rich early nodulin mediates a predominant gene expression in the interzone ii-iii region of transgenic vicia hirsuta root nodules. | we recently reported on the broad bean gene vfenod-grp3 encoding a glycine-rich early nodulin. this gene was predominantly expressed in the interzone ii-iii region of vicia faba root nodules. the vfenod-grp3 promoter contained several sequence motifs potentially involved in the regulation of gene expression. to investigate the molecular basis for the specific vfenod-grp3 expression, defined vfenod-grp3 promoter fragments were fused to an intron-containing gusaint gene. agrobacterium rhizogenes a ... | 1995 | 8541502 |
| mspg3, a medicago sativa polygalacturonase gene expressed during the alfalfa-rhizobium meliloti interaction. | polygalacturonase (pg) is one of the most important enzymes associated with plant cell wall degradation. it has been proposed to participate in the early steps of the rhizobium-legume interaction. we have identified two classes of cdna fragments corresponding to two classes of pg genes in the medicago genome. one of this class, represented by e2 in m. truncatula and pl1 in m. sativa, seems to be related to previously characterized plant pg genes expressed in pollen. we have isolated the genomic ... | 1998 | 9689142 |
| vsenbp1 regulates the expression of the early nodulin psenod12b. | a dna-binding protein, vsenbp1, previously isolated from vicia sativa was shown to bind in a sequence-specific manner to the early nodulin enod12 gene promoter from pisum sativum. here, the functional importance of the vsenbp1 binding sites on the psenod12b promoter has been studied in vivo. a promoter-gusa fusion in which a mutation was introduced at the putative target sequence, aataa, was inactive in nodules of transgenic vicia hirsuta roots. gel retardation assays showed that vsenbp1 does no ... | 1999 | 10437833 |
| cpp1, a dna-binding protein involved in the expression of a soybean leghemoglobin c3 gene. | nodulin genes are specifically expressed in the nitrogen-fixing root nodules. we have identified a novel type of dna-binding protein (cpp1) interacting with the promoter of the soybean leghemoglobin gene gmlbc3. the dna-binding domain of cpp1 contains two similar cys-rich domains with 9 and 10 cys, respectively. genes encoding similar domains have been identified in arabidopsis thaliana, caenorhabditis elegans, the mouse, and human. the domains also have some homology to a cys-rich region presen ... | 2000 | 10859345 |
| nodule-expressed cyp15a cysteine protease genes map to syntenic genome regions in pisum and medicago spp. | pscyp15a is a gene that encodes a vacuolar cysteine protease expressed in wilt-induced shoots of pisum sativum (pea) and in root nodules. to further the understanding of nodular pscyp15a expression, a region 5' to the coding sequence of the gene was cloned. varying lengths of 5' untranslated sequence were fused with the uida coding region and introduced from agrobacterium rhizogenes into "hairy roots" of vicia hirsuta. in this transgenic root nodulation assay, a promoter sequence of 900 bp was s ... | 2000 | 10875332 |
| the broad bean nodulin vfenod18 is a member of a novel family of plant proteins with homologies to the bacterial mj0577 superfamily. | full-length transcript sequences were isolated from broad bean root nodules, which encode a novel nodulin designated vfenod18. the corresponding transcripts were detected in early and in late stages of nodule development and were localized exclusively in the nitrogen-fixing zone iii. the vfenod18 sequence is not only homologous to a number of ests from various mono- and dicotyledonous plants, but also to the atp-binding protein mj0577 from methanococcus jannaschii and to a range of bacterial pro ... | 2000 | 11085263 |
| the promoter of the vicia faba l. gene vfenod12 encoding an early nodulin is active in cortical cells and nodule primordia of transgenic hairy roots of vicia hirsuta as well as in the prefixing zone ii of mature transgenic v. hirsuta root nodules. | a full-length cdna encoding the vicia faba l. early nodulin vfenod12 was isolated. the deduced protein sequence specified a 90 amino acid protein with a mw of 10206 and contained a putative signal peptide sequence followed by ppx(3) repeats characteristic of enod12 proteins. the vfenod12 gene was found to be expressed specifically in root nodules as early as 3 days post inoculation with rhizobium leguminosarum bv. viciae. in mature nodules, vfenod12 transcripts were confined to the prefixing zon ... | 2000 | 11164578 |
| genetic diversity of indigenous rhizobium leguminosarum bv. viciae isolates nodulating two different host plants during soil restoration with alfalfa. | a total of 360 rhizobium leguminosarum bv. viciae strains was isolated from three brown-coal mining restoration fields of different age and plant cover (without and in the first and second year of alfalfa, medicago sativa, cultivation) using two host species (vicia hirsuta and pisum sativum) as capture plants. the strains were genetically typed by restriction fragment length polymorphism analysis of polymerase chain reaction (pcr)-generated 16s-23s ribosomal dna intergenic spacer regions (igs-rf ... | 2001 | 11555271 |
| the nodulin vfenod18 is an atp-binding protein in infected cells of vicia faba l. nodules. | recently we described the novel nodulin gene vfenod18, whose corresponding transcripts were restricted to the nitrogen-fixing zone iii of broad bean root nodules. to characterize vfenod18 on the protein level, polyclonal antibodies were generated using the purified recombinant vfenod18 protein produced in escherichia coli by employing the pmal-c expression system. these antibodies recognized immunoreactive proteins isolated from indeterminate nodules of different leguminous plants, but also from ... | 2001 | 11785936 |
| a hu-like gene mutation in rhizobium leguminosarum bv. viciae affects the expression of nodulation genes. | nodd is the major regulator of nod genes expression in rhizobia. previously, a hu-like protein in rhizobium leguminosarum bv. viciae has been identified to bind specifically with nod promoters and be involved in in vitro nodd transcription, but its in vivo function remained unknown. in this work we have cloned and sequenced the r. leguminosarum bv. viciae gene, named hurl, for this hu-like protein. using the e. coli-expressed hurl proteins, we proved that hurl had high affinity to several nod pr ... | 2004 | 14731285 |
| fast and sensitive in vivo studies under controlled environmental conditions to substitute long-term field trials with genetically modified plants. | we introduce an easy, fast and effective method to analyze the influence of genetically modified (gm) plants on soil and model organisms in the laboratory to substitute laborious and time consuming field trials. for the studies described here we focused on two gm plants of the so-called 3rd generation: gm plants producing pharmaceuticals (pmp) and plant made industrials (pmi). cyanophycin synthetase (cpha) was chosen as model for pmi and choleratoxin b (ctb) as model for pmp. the model genes are ... | 2017 | 28011129 |
| mgte from rhizobium leguminosarum is a mg²⁺ channel essential for growth at low ph and n2 fixation on specific plants. | mgte is predicted to be a rhizobium leguminosarum channel and is essential for growth when both mg²⁺ is limiting and the ph is low. n₂was only fixed at 8% of the rate of wild type when the crop legume pisum sativum was inoculated with an mgte mutant of r. leguminosarum and, although bacteroids were present, they were few in number and not fully developed. r. leguminosarum mgte was also essential for n₂fixation on the native legume vicia hirsuta but not when in symbiosis with vicia faba. the impo ... | 2015 | 26422403 |
| rhizobium leguminosarum genes required for expression and transfer of host specific nodulation. | the contributions of various nod genes from rhizobium leguminosarum biovar viceae to host-specific nodulation have been assessed by transferring specific genes and groups of genes to r. leguminosarum bv. trifolii and testing the levels of nodulation on pisum sativum (peas) and vicia hirsuta. many of the nod genes are important in determination of host-specificity; the node gene plays a key (but not essential) role and the efficiency of transfer of host specific nodulation increased with addition ... | 1989 | 24272714 |
| promoters in the nodulation region of the rhizobium leguminosarum sym plasmid prl1ji. | a region of 16.8 kb of the sym(biosis) plasmid prl1ji of rhizobium leguminosarum, consisting of the established 9.7 kb nodulation region which confers nodulation ability on vicia hirsuta and a region of 7.1 kb which appeared to be necessary for nodulation on v. sativa and trifolium subterraneum, was subcloned as fragments of maximally 2.5 kb in a newly developed incq transcriptional fusion vector. the expression of these fragments was studied in rhizobium. one constitutive promoter, pr.nodd, and ... | 1987 | 24276795 |
| volatile seed germination inhibitors from plant residues. | volatile emissions from residues of the winter cover legumes, berseem clover (trifolium alexandrinum l.), hairy vetch [vicia hirsuta (l.) s.f. gray], and crimson clover (trifolium incarnatum l.), inhibited germination and seedling development of onion, carrot, and tomato. using gc-ms, 31 c2-c10 hydrocarbons, alcohols, aldehydes, ketones, esters, furans, and monoterpenes were identified in these residue emission mixtures. mixtures of similar compounds were found in the volatiles released by herbi ... | 1990 | 24263582 |