Mol Plant Microbe Interact
September 2024
The soilborne Gram-negative phytopathogenic beta-proteobacterium strain OE1-1 produces methyl 3-hydroxymyristate (3-OH MAME) as the quorum sensing (QS) signal by the methyltransferase PhcB and senses the chemical, activating the LysR family transcriptional regulator PhcA, which regulates the QS-dependent genes responsible for QS-dependent phenotypes including virulence. The sensor histidine kinases PhcS and VsrA are reportedly involved in the regulation of QS-dependent genes. To elucidate the function of PhcS and VsrA in the active QS, we generated the deletion and -deletion mutants, which exhibited weak changes to their QS-dependent phenotypes including virulence.
View Article and Find Full Text PDFspecies complex (RSSC) shows a broad host range and is classified into four phylotypes. To compare type III effectors, we have determined the complete genome sequences of several RSSC strains, especially phylotype-I strains isolated in Japan, with different host specificity.
View Article and Find Full Text PDFThe soil-borne phytopathogenic gram-negative bacterium species complex (RSSC) produces staphyloferrin B and micacocidin as siderophores that scavenge for trivalent iron (Fe) in the environment, depending on the intracellular divalent iron (Fe) concentration. The staphyloferrin B-deficient mutant reportedly retains its virulence, but the relationship between micacocidin and virulence remains unconfirmed. To elucidate the effect of micacocidin on RSSC virulence, we generated the micacocidin productivity-deficient mutant (Δ) that lacks , which encodes a putative polyketide synthase/non-ribosomal peptide synthetase, using the RSSC phylotype I strain OE1-1.
View Article and Find Full Text PDFPlant Biotechnol (Tokyo)
March 2023
Phospholipid signaling plays an important role in plant immune responses. Here, we isolated two phospholipase C4 (PLC4) orthologs in the genome, designated as and ( and ). We created and - silenced plants.
View Article and Find Full Text PDFTarget of rapamycin (TOR) regulates essential processes associated with plant growth, development, and cell death by modulating metabolic activities and translation in response to environmental signals. The ATP-competitive TOR inhibitor AZD8055 suppressed the hypersensitive response (HR) cell death in infected with the incompatible . The induced expression of the HR marker gene was also inhibited by the AZD8055 treatment.
View Article and Find Full Text PDFPathogen genetic diversity varies in response to environmental changes. However, it remains unclear whether plant barriers to invasion could be considered a genetic bottleneck for phytopathogen populations. Here, we implement a barcoding approach to generate a pool of 90 isogenic and individually barcoded Ralstonia solanacearum strains.
View Article and Find Full Text PDFThe gram-negative plant-pathogenic β-proteobacterium Ralstonia pseudosolanacearum strain OE1-1 produces methyl 3-hydroxymyristate as a quorum sensing (QS) signal through methyltransferase PhcB and senses the chemical via the sensor histidine kinase PhcS. This leads to activation of the LysR family transcription regulator PhcA, which regulates the genes (QS-dependent genes) responsible for QS-dependent phenotypes, including virulence. The transcription regulator ChpA, which possesses a response regulator receiver domain and also a hybrid sensor histidine kinase/response regulator phosphore-acceptor domain but lacks a DNA-binding domain, is reportedly involved in QS-dependent biofilm formation and virulence of R.
View Article and Find Full Text PDFPhospholipid signaling plays important roles in plant immune responses. Here, we focused on two phospholipase C3 (PLC3) orthologs in the Nicotiana benthamiana genome, NbPLC3-1 and NbPLC3-2. We generated NbPLC3-1 and NbPLC3-2-double-silenced plants (NbPLC3s-silenced plants).
View Article and Find Full Text PDFThe increasing rate of carbon dioxide (CO) emissions and its impact on global warming are a tremendous problem globally. To control these problems, the present research attempted to employ the for growth-dependent enhanced CO sequestration using cattle waste (cow dung, CD and cow urine, CU). Two experiments of growth using six different percentages of CD and CU (0.
View Article and Find Full Text PDFAfter infecting roots of tomato plants, the gram-negative bacterium Ralstonia pseudosolanacearum strain OE1-1 activates quorum sensing (QS) to induce production of plant cell wall-degrading enzymes, such as β-1,4-endoglucanase (Egl) and β-1,4-cellobiohydrolase (CbhA), via the LysR family transcriptional regulator PhcA and then invades xylem vessels to exhibit virulence. The phcA-deletion mutant (ΔphcA) exhibits neither the ability to infect xylem vessels nor virulence. Compared with strain OE1-1, the egl-deletion mutant (Δegl) exhibits lower cellulose degradation activity, lower infectivity in xylem vessels, and reduced virulence.
View Article and Find Full Text PDFWe present the draft genome sequences of bacterial strains of the genera and . Polysaccharide utilization loci (PULs) were found in all of the ulvan utilizers. Comparison of the PULs will elucidate the degradation pathway for ulvan.
View Article and Find Full Text PDFWe present the complete genome sequences of Ralstonia solanacearum strains isolated from ginger plants. Strains MAFF 211471, MAFF 211479, MAFF 211491, MAFF 301560, MAFF 241647, and MAFF 241648 contain 69, 64, 65, 69, 72, and 64 type III effector genes, respectively.
View Article and Find Full Text PDFspecies complex (RSSC) strains are plant pathogens that produce lipopeptides (ralstonins and ralstoamides) by the polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) enzyme hybrid. Recently, ralstonins were found to be key molecules in the parasitism of RSSC to other hosts, and fungi. The PKS-NRPS genes of RSSC strains in the GenBank database suggest the production of additional lipopeptides, although it has not been confirmed to date.
View Article and Find Full Text PDFReal haptics is a technology that reproduces the sense of force and touch by transmitting contact information with real objects by converting human movements and the feel of the objects into data. In recent years, real haptics technology has been installed in several surgical devices. A custom-made surgical drill was used to drill into the posterior lamina to verify the time required for penetration detection and the distance the drill advanced after penetration.
View Article and Find Full Text PDFThe soil-borne Gram-negative β-proteobacterium Ralstonia solanacearum species complex (RSSC) infects tomato roots through the wounds where secondary roots emerge, infecting xylem vessels. Because it is difficult to observe the behavior of RSSC by a fluorescence-based microscopic approach at high magnification, we have little information on its behavior at the root apexes in tomato roots. To analyze the infection route of a strain of phylotype I of RSSC, R.
View Article and Find Full Text PDFThe structure of food webs and carbon flow in aquatic ecosystems can be better understood by studying contributing factors such as the diets of herbivorous fish. Metabarcoding using a high-throughput sequencer has recently been used to clarify prey organisms of various fish except herbivorous fish. Since sequences of predator fish have dominated in sequences obtained by metabarcoding, we investigated a method for suppressing the amplification of fish DNA by using a blocking primer or peptide nucleic acid (PNA) clamp to determine the prey organisms of herbivorous fish.
View Article and Find Full Text PDFA syringe-like type III secretion system (T3SS) plays essential roles in the pathogenicity of Ralstonia solanacearum, which is a causal agent of bacterial wilt disease on many plant species worldwide. Here, we characterized functional roles of a CysB regulator (RSc2427) in R. solanacearum OE1-1 that was demonstrated to be responsible for cysteine synthesis, expression of the T3SS genes, and pathogenicity of R.
View Article and Find Full Text PDFPlant Biotechnol (Tokyo)
September 2021
Phosphatidic acid plays an important role in immune responses against phytopathogenic bacteria. We analyzed the contributions of endoplasmic reticulum-derived chloroplast phospholipids, including phosphatidic acid, to the resistance of against . Here, we focused on trigalactosyldiacylglycerol 3 (TGD3) protein as a candidate required for phosphatidic acid signaling.
View Article and Find Full Text PDFMol Plant Microbe Interact
November 2021
RSc0454 is predicted as a FAD-linked oxidase based on protein homologies, while it contains distinct domains of lactate dehydrogenase and succinate dehydrogenase. A previous study demonstrated that RSc0454 exhibits lactate dehydrogenase activity using pyruvate and NADH as substrates, and is essential for pathogenicity of . Here, we genetically characterized involvement of RSc0454 on bacterial growth and expression of genes for the type III secretion system (T3SS, a pathogenicity determinant) in .
View Article and Find Full Text PDFThe Tn-based genomic integration system enables direct insertion of foreign gene elements into the chromosome downstream of in many bacteria species. The gene is greatly conserved in species complex (RSSC), while its downstream regions are mostly different in the RSSC. Here, we provided genetic evidence to validate that this Tn integration is dependent on a conserved 30-bp motif in the , called an Tn box, and artificial Tn boxes elsewhere are competent for the Tn integration, which is further confirmed to be simultaneous downstream of both original and artificial Tn boxes, using PCR.
View Article and Find Full Text PDFMinim Invasive Ther Allied Technol
April 2022
Purpose: The present study used haptic technology to determine the safe forceps grip force for preventing organ damage when handling the intestinal tract.
Material And Methods: The small intestines of ten male beagle dogs (weighing 9.5-10 kg) were grasped with the entire forceps for one minute; the small intestines were then pulled out of the forceps and evaluated for damage.
Background: Microsurgery requires high skills for suturing using fragile threads, often within narrow surgical fields. Precise tension is required for good healing and to avoid the risk of thread breakage.
Methods: To meet the demands, we developed a novel assist robot utilizing high-precision sensorless haptic technology.