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OBJECTIVE: Interstitial lung disease (ILD) is classified into several disease groups. Among them, idiopathic pulmonary fibrosis (IPF) has higher incidence and poor prognosis; therefore, it is important to characterize specific IPF symptoms. Exercise desaturation is a strong factor related to mortality in patients with ILD. Thus, the purpose of this study was to compare the degree of oxygen desaturation between IPF and other ILD (non-IPF ILD) patients during exercise, using the 6-minute walk test (6MWT). METHODS: This retrospective study included 126 stable patients with ILD who underwent 6MWT in our outpatient department. The 6MWT was used to assess desaturation during exercise, 6-minute walk distance (6MWD), and dyspnea at the end of exercise. In addition, patient characteristics and pulmonary function test results were recorded. RESULTS: Study subjects were divided into 51 IPF patients and 75 non-IPF ILD patients. The IPF group had significantly lower nadir oxygen saturation determined by pulse oximetry (SpO2) during 6MWT than the non-IPF ILD group (IPF, 86.5 ± 4.6%; non-IPF ILD, 88.7 ± 5.3%; p = 0.02). The significant association between the nadir SpO2 and IPF or non-IPF ILD grouping remained even after adjusting for gender, age, body mass index, lung function, 6MWD, and dyspnea (ß = -1.62; p <0.05). CONCLUSION: Even after adjusting for confounding factors, IPF patients had lower nadir SpO2 during 6MWT. Early assessment of exercise desaturation using the 6MWT may be more important in patients with IPF compared with patients with other ILDs.
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Pseudomonas cannabina pv. alisalensis (Pcal) causes bacterial blight on cabbage. We previously conducted a screening for reduced virulence using Tn5 transposon mutants and identified one of the transcriptional factors, HexR, as a potential Pcal virulence factor. However, the role of HexR in plant pathogenic Pseudomonas virulence has not been investigated well. Here, we demonstrated that the Pcal hexR mutant showed reduced disease symptoms and bacterial populations on cabbage, indicating that HexR contributes to Pcal virulence. We used RNA-seq analysis to characterize the genes regulated by HexR. We found that several type three secretion system (T3SS)-related genes had lower expression of the Pcal hexR mutant. Five genes were related to T3SS machinery, two genes were related to type three helper proteins, and three genes encoded type three effectors (T3Es). We also confirmed that T3SS-related genes, including hrpL, avrPto, hopM1, and avrE1, were also down-regulated in the Pcal hexR mutant both in culture and in vivo by using RT-qPCR. T3SS functions to suppress plant defense in host plants and induce hypersensitive response (HR) cell death in non-host plants. Therefore, we investigated the expression profiles of cabbage defense-related genes, including PR1 and PR5, and found that the expressions of these genes were greater in the Pcal hexR mutant. We also demonstrated that the hexR mutant did not induce HR cell death in non-host plants, indicating that HexR contributes in causing HR in nonhost plants. Together, these results indicate that the mutation in hexR leads to a reduction in the T3SS-related gene expression and thus an impairment in plant defense suppression, reducing Pcal virulence.
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PURPOSE: Physical activity is important to improve recovery following surgery. This study investigated the impact of physical activity on the development of pneumonia after radical esophagectomy in patients with thoracic esophageal cancer in the subacute phase from postoperative day 11 to hospital discharge. METHODS: This retrospective cohort study included 83 patients who underwent radical esophagectomy for esophageal cancer between 2016 and 2022. Physical activity was measured using an activity tracker, and the average number of steps between postoperative days 8 and 10 was examined. The primary outcome was pneumonia (Clavien-Dindo classification 2 or higher) developing between postoperative day 11 and hospital discharge. We used the receiver operating characteristic (ROC) curve analysis to calculate the optimal cutoff value of physical activity that can predict the development of pneumonia and define low physical activity. We used logistic regression analysis to investigate the impact of low physical activity on postoperative pneumonia. RESULTS: Pneumonia developed in 10 patients (12.0%) during the observation period. The optimal cutoff value of physical activity for predicting pneumonia was 1494 steps per day (sensitivity: 60.0%, specificity: 89.0%, area under the curve: 0.743). In multivariate analysis, low physical activity was an independent predictor of incident pneumonia [odds ratio: 12.10, 95% confidence interval: 2.21-65.90, p = 0.004], with adjustment for age, gastric tube reconstruction route, and postoperative recurrent nerve palsy. CONCLUSIONS: Physical activity following radical esophagectomy in patients with thoracic esophageal cancer was an independent predictor of the development of pneumonia in the subacute phase after radical esophagectomy.
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Neoplasias Esofágicas , Neumonía , Humanos , Esofagectomía/efectos adversos , Estudios Retrospectivos , Factores de Riesgo , Neumonía/epidemiología , Neumonía/etiología , Neumonía/cirugía , Neoplasias Esofágicas/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiologíaRESUMEN
BACKGROUND: Sarcopenia, defined using abdominal computed tomography (CT), has been used as a prognostic marker for patients with idiopathic pulmonary fibrosis (IPF). However, no consensus on the impact of sarcopenia as defined using chest CT exists. Therefore, this study aimed to investigate the impact of sarcopenia, defined using CT at the carina-level, on the long-term prognosis of patients with IPF. METHODS: This single-center retrospective cohort study included 117 patients with IPF. Sarcopenia was defined as skeletal muscle mass measured at the carina-level on chest CT images. All-cause mortality was analyzed using the Kaplan-Meier method, and the log-rank test was used to evaluate the differences between sarcopenia and non-sarcopenia groups. A Cox proportional hazards regression model was used to analyze the impact of sarcopenia on all-cause mortality in model 1 with adjustment for body mass index and gender-age-physiology stage as a confounding factor and in model 2 with sex, age, and% forced vital capacity (FVC). RESULTS: The median follow-up period was 956 days, and 57 deaths were recorded. The sarcopenia group had a significantly lower survival rate than the non-sarcopenia group. The multivariate Cox proportional hazards analysis revealed that sarcopenia was a significant predictor of all-cause mortality in models 1 and 2. In patients with no diffusing capacity for carbon monoxide (DLCO) measurement, sarcopenia was a significant prognostic predictor of all-cause mortality independent of%FVC. CONCLUSION: Sarcopenia, defined at the carina level, is a risk factor for all-cause mortality in patients with IPF. Assessment of sarcopenia by CT imaging is useful and less burdensome in patients with IPF.
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Fibrosis Pulmonar Idiopática , Sarcopenia , Humanos , Fibrosis Pulmonar Idiopática/diagnóstico por imagen , Fibrosis Pulmonar Idiopática/epidemiología , Estudios Retrospectivos , Pronóstico , Capacidad Vital , Sarcopenia/diagnóstico por imagen , Sarcopenia/epidemiología , Músculo Esquelético/diagnóstico por imagenRESUMEN
Phytopathogenic bacterial strains (MAFF 311094T, MAFF 311095, MAFF 311096 and MAFF 311097), which were isolated from rot lesions of parsley (Petroselinum crispum) sampled in Miyagi, Japan, were subjected to polyphasic characterization to determine their taxonomic position. The cells were Gram-reaction-negative, aerobic, non-spore-forming, motile with one or two polar flagella and rod-shaped. The 16S rRNA gene sequences analyses revealed that the strains belong to the genus Pseudomonas, exhibiting the highest sequence similarity to Pseudomonas sivasensis P7T (99.93% sequence similarity), Pseudomonas cyclaminis MAFF 301449T (99.93â%), Pseudomonas extremaustralis 14-3T (99.86â%), Pseudomonas kitaguniensis MAFF 212408T (99.86â%) and Pseudomonas antarctica CMS 35T (99.79â%). The genomic DNA G+C content was 60.1 mol%, and the major cellular fatty acids (>5â% of the total fatty acids) were C16:0, summed feature 3 (C16:1 ω7c/C16:1 ω6c), summed feature 8 (C18:1 ω7c/C18:1 ω6c) and C17:0 cyclo. The rpoD sequence-based phylogenetic and whole genome-based phylogenomic analyses demonstrated that the strains are a member of the Pseudomonas fluorescens subgroup, but their phylogenetic position does not match those of any members of this subgroup. The average nucleotide identity and digital DNA-DNA hybridization values between the strains and their closely related species were ≤90.64% and ≤41.9â%, respectively, which were below the thresholds for prokaryotic species delineation (95-96 and 70%, respectively). Phenotypic characteristics, pathogenicity toward parsley and cellular fatty acid composition could differentiate the strains from their closest relatives. The phenotypic, chemotaxonomic and genotypic data presented in this study revealed that the strains constitute a novel Pseudomonas species, for which we propose the name Pseudomonas petroselini sp. nov., with MAFF 311094T (=ICMP 24279T) being the type strain.
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Genes Bacterianos , Petroselinum , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Japón , Petroselinum/genética , Filogenia , Pseudomonas , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
OBJECTIVES: This study aimed to assess the effect of home-based preoperative pulmonary rehabilitation (HBPPR) on the incidence of postoperative complications, length of stay (LOS), and duration of intercostal catheterization in non-small cell lung cancer (NSCLC) patients who underwent lung resection. MATERIALS AND METHODS: In this retrospective cohort study, 144 patients who underwent lung resection were recruited, 51 of whom received HBPPR, comprising respiratory muscle training and was supervised (for patients undergoing it for the first time). Patients continued these programs for 2-4 weeks during the preoperative waiting period, in their homes. Data on postoperative complications graded according to the Clavien-Dindo classification, LOS, and intercostal catheterization duration were collected from medical records. These outcomes were compared between the HBPPR and non-HBPPR groups using Fisher's exact test and Wilcoxon rank sum test, after 1:1 propensity score matching to avoid selection bias. RESULTS: Forty-nine matched pairs were extracted using propensity score matching. HBPPR reduced the onset of postoperative complications (p = 0.04), with the relative ratio (RR) for Clavien-Dindo Class I postoperative complications showing a significant difference (RR 0.55, 95% CI 0.30-1.02; p = 0.05), whereas RRs for the other Clavien-Dindo classes were not statistically significant. There was no significant difference in LOS or the duration of intercostal catheterization. CONCLUSION: HBPPR reduced the incidence of Clavien-Dindo Class I postoperative complications after lung resection. Implementing HBPPR practices in a clinical setting would benefit patients unable to receive supervised preoperative pulmonary rehabilitation due to access barriers, time, and financial constraints.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Procedimientos Quirúrgicos Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Humanos , Pulmón , Neoplasias Pulmonares/cirugía , Complicaciones Posoperatorias/epidemiología , Estudios RetrospectivosRESUMEN
Geobacter sulfurreducens produces high current densities and it has been used as a model organism for extracellular electron transfer studies. Nine G. sulfurreducens strains were isolated from biofilms formed on an anode poised at -0.2 V (vs SHE) in a bioelectrochemical system in which river sediment was used as an inoculum. The maximum current density of an isolate, strain YM18 (9.29 A/m2), was higher than that of the strain PCA (5.72 A/m2), the type strain of G. sulfurreducens, and comparable to strain KN400 (8.38 A/m2), which is another high current-producing strain of G. sulfurreducens. Genomic comparison of strains PCA, KN400 and YM18 revealed that omcB, xapD, spc and ompJ, which are known to be important genes for iron reduction and current production in PCA, were not present in YM18. In the PCA and KN400 genomes, two and one region(s) encoding CRISPR/Cas systems were identified, respectively, but they were missing in the YM18 genome. These results indicate that there is genetic variation in the key components involved in extracellular electron transfer among G. sulfurreducens strains.
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Variación Genética , Genoma Bacteriano , Geobacter , Electrodos , Transporte de Electrón , Genoma Bacteriano/genética , Genómica , Geobacter/genéticaRESUMEN
Here, we report the complete genome sequence of Geobacter sulfurreducens strain YM35, which was isolated from biofilms formed on an anode in a bioelectrochemical system where river sediment was used as an inoculum. The chromosome is 3,745,223 bp with a G+C content of 60.9%. The chromosome contains 3,324 protein-coding genes.
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Two phytopathogenic bacteria, MAFF 301380T and MAFF 301381, isolated from rot lesions of lettuce (Lactuca sativa L. var. capitata L.) in Japan, were characterized using a polyphasic approach. The cells were Gram-reaction-negative, aerobic, non-spore-forming, rod-shaped and motile with one to three polar flagella. Analysis of the 16S rRNA gene sequences showed that the strains belong to the genus Pseudomonas and are closely related to Pseudomonas cedrina subsp. cedrina CFML 96-198T (99.72â%), Pseudomonas cedrina subsp. fulgida P515/12T (99.65â%), Pseudomonas gessardii DSM 17152T (99.51â%), Pseudomonas synxantha DSM 18928T (99.44â%), Pseudomonas libanensis CIP 105460T (99.44â%) and Pseudomonas lactis DSM 29167T (99.44â%). The genomic DNA G+C content was 60.4 mol% and the major fatty acids consisted of summed feature 3 (C16â:â1 ω7c/C16â:â1 ω6c), C16â:â0 and summed feature 8 (C18â:â1 ω7c/C18â:â1 ω6c). Phylogenetic analysis using the rpoD gene sequences and phylogenomic analyses based on the whole genome sequences demonstrated that the strains are members of the Pseudomonas fluorescens subgroup but formed a monophyletic and robust clade separated from their closest relatives. The average nucleotide identity and digital DNA-DNA hybridization values between the strains and their closely related species were 88.65â% or less and 36.3â% or less, respectively. The strains could be distinguished from their closest relatives by phenotypic characteristics, pathogenicity towards lettuce and whole-cell MALDI-TOF MS profiles. The evidence presented in this study supports the classification of the strains as representing a novel Pseudomonas species, for which we propose the name Pseudomonas lactucae sp. nov., with the type strain MAFF 301380T (=ICMP 23838T).
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Lactuca/microbiología , Filogenia , Enfermedades de las Plantas/microbiología , Pseudomonas/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Japón , Hibridación de Ácido Nucleico , Pseudomonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
An outer membrane c-type cytochrome (OmcZ) in Geobacter sulfurreducens is essential for optimal current production in microbial fuel cells. OmcZ exists in two forms, small and large, designated OmcZS and OmcZL, respectively. However, it is still not known how these two structures are formed. A mutant with a disruption of the GSU2075 gene encoding a subtilisin-like serine protease (designated ozpA for the OmcZprotease), which is located downstream of omcZ, produced low currents at a level similar to that of the omcZ-deficient mutant strain. Biochemical analyses revealed that the ozpA mutant accumulated OmcZL and did not produce OmcZS, which is thought to be a mature form that is essential for the extracellular electron transfer to the electrode. A heterologous expression system cell lysate from an Escherichia coli strain producing OzpA cleaved OmcZL and generated OmcZS as the proteolytic product. Among the culture supernatant, loosely bound outer surface, and intracellular protein fractions from wild-type G. sulfurreducens, only the culture supernatant protein fraction showed OmcZL cleavage activity, indicating that the mature form of OmcZ, OmcZS, can be produced outside the cells. These results indicate that OzpA is an essential protease for current production via the maturation of OmcZ, and OmcZS is the key to the extracellular electron transfer to electrodes. This proteolytic maturation of OmcZ is a unique regulation among known c-type cytochromes in G. sulfurreducens. IMPORTANCE Microbial fuel cells are a promising technology for energy generation from various waste types. However, the molecular mechanisms of microbial extracellular electron transfer to the electrode need to be elucidated. G. sulfurreducens is a common key player in electricity generation in mixed-culture microbial fuel cell systems and a model microorganism for the study of extracellular electron transfer. Outer membrane c-type cytochrome OmcZ is essential for an optimal current production by G. sulfurreducens. OmcZ proteolytic cleavage occurs during maturation, but the underlying mechanism is unknown. This study identifies a subtilisin-like protease, OzpA, which plays a role in cleaving OmcZ and generating the mature form of OmcZ (OmcZS). OzpA is essential for current production and, thus, the proteolytic maturation of OmcZ. This is a novel regulation of the c-type cytochrome for G. sulfurreducens extracellular electron transfer. This study also provides new insights into the design strategy and development of microbial extracellular electron transfer for an efficient energy conversion from chemical energy to electricity.
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Proteínas de la Membrana Bacteriana Externa/metabolismo , Fuentes de Energía Bioeléctrica , Geobacter/metabolismo , Serina Proteasas/metabolismo , Electricidad , Geobacter/genética , Mutación , Proteolisis , Serina Proteasas/genéticaRESUMEN
Mitsuaria sp. TWR114 is a biocontrol agent against tomato bacterial wilt (TBW). We aimed to gain genomic insights relevant to the biocontrol mechanisms and colonization ability of this strain. The draft genome size was found to be 5,632,523 bp, with a GC content of 69.5%, assembled into 1144 scaffolds. Genome annotation predicted a total of 4675 protein coding sequences (CDSs), 914 pseudogenes, 49 transfer RNAs, 3 noncoding RNAs, and 2 ribosomal RNAs. Genome analysis identified multiple CDSs associated with various pathways for the metabolism and transport of amino acids and carbohydrates, motility and chemotactic capacities, protection against stresses (oxidative, antibiotic, and phage), production of secondary metabolites, peptidases, quorum-quenching enzymes, and indole-3-acetic acid, as well as protein secretion systems and their related appendages. The genome resource will extend our understanding of the genomic features related to TWR114's biocontrol and colonization abilities and facilitate its development as a new biopesticide against TBW.
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Agentes de Control Biológico , Burkholderiales/genética , Genoma Bacteriano , Enfermedades de las Plantas/prevención & control , Solanum lycopersicum/microbiología , Proteínas Bacterianas/genética , Composición de Base , Agentes de Control Biológico/metabolismo , Burkholderiales/metabolismo , ADN Bacteriano/química , Genómica , Ácidos Indolacéticos/metabolismo , Enfermedades de las Plantas/microbiología , Metabolismo Secundario/genética , Estrés FisiológicoRESUMEN
Pseudomonas cannabina pv. alisalensis and Pseudomonas syringae pv. maculicola cause bacterial leaf blight and bacterial leaf spot of crucifers (Brassicaceae). Both pathogens are threats to the cultivation of cruciferous crops. Here, we sequenced two strains of each pathogen, which will contribute to the development of countermeasures for the above diseases.
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Black rot and bacterial spots threaten the cultivation of cruciferous vegetables worldwide, and the development of a method that can easily detect, identify, and distinguish their respective pathogens Xanthomonas campestris pv. campestris (Xcc) and X. campestris pv. raphani (Xcr) is required. Multiple whole-genome sequences of Xcc and Xcr were aligned to identify specific regions and subsequently design gene markers. A region present in Xcr, but absent in Xcc, was detected, which was approximately 11.5 kbp in length, sandwiched between the serine protease homolog (SPH) and nicotinate phosphoribosyltransferase gene (pncB). It contained putative cellulose synthesis-related genes, whereas Xcc only had a modified cellulose synthase gene. Designed primers were pncB_fw1 and pncB_fw2 (from the pncB gene), Xcc_rv1 and Xcc_rv2 (from the modified cellulose synthesis gene), and Xcr_rv1 and Xcr_rv2 (from the putative first and second open reading frames of the gene cluster). PCR using pncB_fw1 and Xcc_rv1, or pncB_fw2 and Xcc_rv2, amplified DNA fragments only in Xcc and X. campestris pv. incanae (Xci). Xci is the causal agent of black rot of garden stock and closely related to Xcc. PCR using pncB_fw1 and Xcr_rv1, or pncB_2 and Xcr_rv2, amplified DNA fragments only in Xcr. Multiplex PCR analysis easily distinguished Xcc and Xcr from bacterial colonies isolated on growth media and detected the pathogen in symptomatic leaves. Multiplex nested PCR detected the contamination of one seed with Xcc and/or Xcr infection from 1000 seeds. Therefore, the PCR primers designed in this study therefore helped detect and discriminate between Xcc and Xcr. KEY POINTS: ⢠Xanthomonas campestris pv. campestris (Xcc) and pv. raphani (Xcr) were investigated. ⢠Novel primers were designed following whole-genome comparison analyses. ⢠Multiplex PCR with new primers distinguished Xcc and Xcr simultaneously.
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Xanthomonas campestris , Cartilla de ADN/genética , Marcadores Genéticos , Familia de Multigenes , Reacción en Cadena de la Polimerasa Multiplex , Enfermedades de las Plantas , Xanthomonas campestris/genéticaRESUMEN
Six phytopathogenic bacterial strains, MAFF 301512, MAFF 301513, MAFF 301514T, MAFF 301515, MAFF 301516 and MAFF 301517, were isolated from soft rot lesions of onion (Allium cepa L.) in Japan. The cells were Gram-reaction-negative, aerobic, non-spore-forming, motile with one or two polar flagella and rod-shaped. Analysis of their 16S rRNA gene sequences showed that they belong to the genus Pseudomonas, with the highest similarities to Pseudomonas poae DSM 14936T (99.86â%), Pseudomonas simiae OLiT (99.85â%), Pseudomonas trivialis DSM 14937T (99.79â%) and Pseudomonas extremorientalis KMM 3447T (99.79â%). Their genomic DNA G+C content was 60.9 mol% and the major fatty acids (>5â% of the total fatty acids) present were C16â:â0, summed feature 3 (C16â:â1 ω7c/C16â:â1 ω6c), summed feature 8 (C18â:â1 ω7c /C18â:â1 ω6c) and C17â:â0 cyclo. Phylogenetic and phylogenomic analyses based on the rpoD gene and whole genome sequences, respectively, demonstrated that the strains belong to the Pseudomonas fluorescens subgroup, but form a monophyletic and robust clade, with Pseudomonas azotoformans as their neighbour. Between the strains and P. azotoformans, the average nucleotide identity scores were 95.63-95.70â%, whereas the digital DNA-DNA hybridization scores of the strains against their closest relatives, including P. azotoformans, were 65.4â% or less, which are lower than the 70â% cut-off for prokaryotic species delineation. The strains were differentiated from their closest relatives by phenotypic characteristics, pathogenicity in onion and cellular fatty acid composition. The phenotypic, chemotaxonomic and genotypic data showed that the strains represent a novel Pseudomonas species, proposed to be named Pseudomonas allii sp. nov., with MAFF 301514T (=ICMP 23680T) being the type strain.
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Cebollas/microbiología , Filogenia , Enfermedades de las Plantas/microbiología , Pseudomonas/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Japón , Hibridación de Ácido Nucleico , Pseudomonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Pseudomonas syringae pv. actinidiae is the pathogen that causes kiwifruit bacterial canker and is categorized into several groups (biovars). In Japan, biovar 3, known as the pandemic group, was first discovered in 2014. Here, we sequenced the genomes of nine Japanese biovar 3 strains.
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Xanthomonas campestris pv. raphani and X. campestris pv. campestris are the causal agents of bacterial spot and black rot of crucifers (Brassicaceae), respectively. Both pathogens are threats in the cultivation of cruciferous crops such as cabbage. Here, we sequenced a strain of each of these pathogens.
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Phytopathogenic bacteria, MAFF 212426, MAFF 212427T, MAFF 212428 and MAFF 212429, were isolated from head rot lesions of broccoli (Brassica oleracea L. var. italica Plenck) in Hokkaido, Japan, and subjected to polyphasic taxonomic characterization. The cells were Gram-reaction-negative, aerobic, non-spore-forming, motile with one or two polar flagella, rod-shaped and formed pale yellow colonies. Results of 16S rRNA gene sequence analysis showed that they belong to the genus Pseudomonas with the highest similarity to 'Pseudomonas qingdaonensis' JJ3T (99.86â%), Pseudomonas laurentiana GSL-010T (99.22â%), Pseudomonas huaxiensis WCHPs060044T (99.01â%), Pseudomonas japonica NBRC 103040T (98.87â%) and Pseudomonas alkylphenolica KL28T (98.73â%). The genomic DNA G+C content was 63.4 mol% and the major fatty acids (>5â% of the total fatty acids) were summed feature 3 (C16â:â1 ω7c / C16â:â1 ω6c), C16â:â0, summed feature 8 (C18â:â1 ω7c / C18â:â1 ω6c) and C17â:â0 cyclo. Multilocus sequence analysis using the partial rpoD, gyrB and rpoB gene sequences and phylogenomic analyses based on the whole genome sequences demonstrated that the strains are members of the Pseudomonas putida group, but form a monophyletic, robust clade separated from their closest relatives. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values corroborated their novel species status, with 88.39â% (ANI) and 35.8â% (dDDH) as the highest scores with 'P. qingdaonensis' JJ3T. The strains were differentiated from their closest relatives by phenotypic characteristics, pathogenicity on broccoli, and whole-cell MALDI-TOF mass spectrometry profiles. The phenotypic, chemotaxonomic and genotypic data showed that the strains represent a novel Pseudomonas species, for which the name Pseudomonas brassicae sp. nov. is proposed. The type strain is MAFF 212427T (=ICMP 23635T).
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Brassica/microbiología , Filogenia , Enfermedades de las Plantas/microbiología , Pseudomonas/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Japón , Hibridación de Ácido Nucleico , Fosfolípidos/química , Pigmentación , Pseudomonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
The kiwifruit bacterial canker (Pseudomonas syringae pv. actinidiae; Psa) causes severe damage to kiwifruit production worldwide. Psa biovar 6 (Psa6), which was isolated in Japan in 2015, produces two types of phytotoxins: coronatine and phaseolotoxin. To elucidate the unique virulence of Psa6, we performed transcriptomic analysis of phytotoxin synthesis genes and type III effector genes in in vitro cultivation using various media. The genes related to phytotoxin synthesis and effectors of Psa6 were strictly regulated in the coronatine-inducing mediums (HS and HSC); 14 of 23 effector genes and a hrpL sigma factor gene were induced at 3 h after transferring to the media (early-inducible genes), and phytotoxin synthesis genes such as argD of phaseolotoxin and cfl of coronatine were induced at 6 and 12 h after transferring to the media (late-inducible genes). In contrast, induction of these genes was not observed in the hrp-inducing medium. Next, to examine whether the changes in gene expression in different media is specific to Psa6, we investigated gene expression in other related bacteria. For Psa biovar 1 (Psa1), biovar 3 (Psa3), and P. s. pv. glycinea (Psg), no clear trends were observed in expression behavior across various culture media and incubation times. Therefore, Psa6 seems to exert its virulence efficiently by using two phytotoxins and effectors according to environmental changes. This is not seen in other biovars and pathovars, so it is thought that Psa6 has acquired its own balance of virulence.
RESUMEN
Several groups (biovars) of the kiwifruit bacterial canker pathogen Pseudomonas syringae pv. actinidiae are found in Japan. Here, we sequenced and compared 10 genome sequences of biovar 1, a major group in Japan, which is known as the phaseolotoxin producer.