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PHAGE (New Rochelle, N.Y.) Mar 2020is a genus within the whose members encompass free-living and host-associated lifestyles. Despite our growing understanding of the role of mobile genetic elements in...
is a genus within the whose members encompass free-living and host-associated lifestyles. Despite our growing understanding of the role of mobile genetic elements in the biology, ecology, and evolution of this bacterial group, few bacteriophages have been identified and characterized. A bacteriophage that could infect was isolated from barnyard soil. We used electron microscopy and complete genome sequencing to identify the viral family, and evaluated its host range across 10 different species groups using both bacterial lawn and phage lawn assays. The latter assays were carried out using a scalable microplate assay to increase throughput and enable spectrophotometric quantitation. We also performed a phylogenetic analysis to determine the closest relatives of our phage. Phage vB_PagP-SK1 belongs to the genus of the Podoviridae family in the order Caudovirales. The 39,938 bp genome has a modular structure with early, middle, and late genes, along with the characteristic direct terminal repeats of 172 bp. Genome composition and synteny were similar to that of the phage, vB_EamP-L1, with the exception of a few loci that are most similar to genes of phage infecting other members of the A total of 94 strains were surveyed and vB_PagP-SK1 was found to infect 15 strains across three species, predominantly , along with one strain. vB_PagP-SK1 belongs to the genus and has a host range that spans groups, and is most closely related to the phage, vB_EamP-L1. The presence of xenologous genes in its genome indicates that the genome is a mosaic of multiple phages that infect members of the .
PubMed: 36147614
DOI: 10.1089/phage.2019.0012 -
Microbial Pathogenesis Oct 2020to study the distribution of Pantoea agglomerans (P. agglomerans) statistically and the presence of bla type ESβL in the clinical and environmental isolates.
THE PURPOSE
to study the distribution of Pantoea agglomerans (P. agglomerans) statistically and the presence of bla type ESβL in the clinical and environmental isolates.
METHODS
During a period of 2014-2015, 895 blood specimens and 438 hospital environmental samples were collected from one children's hospital in Baghdad city. The results of statistical analysis showed there was no relationship between the infection with P. agglomerans and the sex, while there was a relationship between the infection with the P. agglomerans and the place of residence and also the age of patients.
RESULT
A total of 23 P. agglomerans were isolated during the study, out of 23 isolates, 13 (56.52%) and 10 (43.48%) were isolated from blood specimens and from hospital environment. All 23 isolates had 100% sensitivity rate to Imipenem and the highest resistant rate was (95.65%) to Ampicillin. Out of 23 P. agglomerans, 14 (60.87%) isolates were positive ESβL producing by the screening test.
CONCLUSION
The result of molecular screening of the gene bla showed the presence of this gene only in phenotypically ESBL producing isolates, while all negative ESβL producing isolates don't harboring bla gene. Out of 14 positive ESβL producing P. agglomerans isolates, 5 (35.71%) were harboring bla gene and 9 (64.29%) of positive ESβL producing isolates were don't harboring bla gene (significant difference at ≤0.05).
Topics: Child; Humans; Pantoea
PubMed: 32653435
DOI: 10.1016/j.micpath.2020.104374 -
Carbohydrate Research Oct 2020Lipopolysaccharide (LPS) was isolated from Pantoea agglomerans 7460 cells by phenol-water extraction. Mild acid degradation allowed to separate OPS and lipid A. Lipid A...
Lipopolysaccharide (LPS) was isolated from Pantoea agglomerans 7460 cells by phenol-water extraction. Mild acid degradation allowed to separate OPS and lipid A. Lipid A was analyzed by negative-ion mode ESI MS and found to consist mainly of hexaacylated derivative containing biphosphorylated GlcN disaccharide, four 14:0 (3-OH), 18:0 and 12:0 fatty acids. The structure of the O-specific polysaccharide was established by chemical, NMR and computational methods: The LPS of Р. agglomerans 7460 showed low level of toxicity and pyrogenicity to compare with LPS of E. coli O55:B5 and pyrogenal, respectively. The ability of the modified (succinylated) LPS, which have lost its toxicity, to block the toxic effects of native LPS has been shown.
Topics: Carbohydrate Conformation; Models, Molecular; O Antigens; Pantoea; Phenol; Phosphorylation; Water
PubMed: 32861900
DOI: 10.1016/j.carres.2020.108132 -
Frontiers in Plant Science 2023Walnut blight is a serious bacterial disease that affects the yield and quality of walnuts. is one of the main causative agents of walnut blight. However, there have...
INTRODUCTION
Walnut blight is a serious bacterial disease that affects the yield and quality of walnuts. is one of the main causative agents of walnut blight. However, there have been few studies on the response of walnuts to infection.
METHODS
In this study, the soluble sugar, photosynthesis, antioxidant enzyme activities, and secondary metabolites were measured, and the transcriptomic analysis was performed to determine the response of walnut tissue cultures to infection.
RESULTS
After pathogen inoculation, the soluble sugar content decreased, and photosynthesis was inhibited. Antioxidant enzyme (superoxide dismutase and peroxidase) activities and secondary metabolites (phenol and flavonoid) contents increased, especially in the early stages of inoculation. Transcriptomic analysis revealed that the phenylpropanoid biosynthesis pathway is induced after infection, and pathogen infection promotes ABA and ethylene signal transduction and inhibits auxin signaling. In addition, SA and JA-related gene expression was altered after inoculation with , and the FLS- and calcium-mediated disease resistance signaling pathways were activated. Furthermore, our results suggested an involvement of the R-protein RPM-mediated disease resistance pathway in the response of walnuts to bacterial infections.
DISCUSSION
Our findings indicated that phenylpropanoid biosynthesis, hormone signal transduction, and plant-pathogen interaction have key roles in pathogenic inoculation, which provide insights into the molecular mechanisms in the response of walnuts to infection.
PubMed: 38116156
DOI: 10.3389/fpls.2023.1294643 -
Microbiome Dec 2022Plants and their associated microbiota constitute an assemblage of species known as holobionts. The plant seed microbiome plays an important role in nutrient uptake and...
BACKGROUND
Plants and their associated microbiota constitute an assemblage of species known as holobionts. The plant seed microbiome plays an important role in nutrient uptake and stress attenuation. However, the core vertically transmitted endophytes remain largely unexplored.
RESULTS
To gain valuable insights into the vertical transmission of rice seed core endophytes, we conducted a large-scale analysis of the microbiomes of two generations of six different rice varieties from five microhabitats (bulk soil, rhizosphere, root, stem, and seed) from four geographic locations. We showed that the microhabitat rather than the geographic location and rice variety was the primary driver of the rice microbiome assemblage. The diversity and network complexity of the rice-associated microbiome decreased steadily from far to near the roots, rice exterior to interior, and from belowground to aboveground niches. Remarkably, the microbiomes of the roots, stems, and seeds of the rice interior compartments were not greatly influenced by the external environment. The core bacterial endophytes of rice were primarily comprised of 14 amplicon sequence variants (ASVs), 10 of which, especially ASV_2 (Pantoea) and ASV_48 (Xanthomonas), were identified as potentially vertically transmitted taxa because they existed across generations, were rarely present in exterior rice microhabitats, and were frequently isolated from rice seeds. The genome sequences of Pantoea and Xanthomonas isolated from the parental and offspring seeds showed a high degree of average nucleotide and core protein identity, indicating vertical transmission of seed endophytes across generations. In silico prediction indicated that the seed endophytes Pantoea and Xanthomonas possessed streamlined genomes with short lengths, low-complexity metabolism, and various plant growth-promoting traits. We also found that all strains of Pantoea and Xanthomonas exhibited cellulase activity and produced indole-3-acetic acid. However, most strains exhibited insignificant antagonism to the major pathogens of rice, such as Magnaporthe oryzae and X. oryzae pv. oryzae.
CONCLUSION
Overall, our study revealed that microhabitats, rather than site-specific environmental factors or host varieties, shape the rice microbiome. We discovered the vertically transmitted profiles and keystone taxa of the rice microbiome, which led to the isolation of culturable seed endophytes and investigation of their potential roles in plant-microbiome interactions. Our results provide insights on vertically transmitted microbiota and suggest new avenues for improving plant fitness via the manipulation of seed-associated microbiomes. Video Abstract.
Topics: Oryza; Endophytes; Seeds
PubMed: 36482381
DOI: 10.1186/s40168-022-01422-9 -
Molecular Plant Pathology Nov 2019Pantoea agglomerans (Pa), a widespread commensal bacterium, has evolved into a host-specific gall-forming pathogen on gypsophila and beet by acquiring a plasmid...
Pantoea agglomerans (Pa), a widespread commensal bacterium, has evolved into a host-specific gall-forming pathogen on gypsophila and beet by acquiring a plasmid harbouring a type III secretion system (T3SS) and effectors (T3Es). Pantoea agglomerans pv. gypsophilae (Pag) elicits galls on gypsophila and a hypersensitive response on beet, whereas P. agglomerans pv. betae (Pab) elicits galls on beet and gypsophila. HsvG and HsvB are two paralogous T3Es present in both pathovars and act as host-specific transcription activators on gypsophila and beet, respectively. PthG and PseB are major T3Es that contribute to gall development of Pag and Pab, respectively. To establish the minimal combinations of T3Es that are sufficient to elicit gall symptoms, strains of the nonpathogenic bacteria Pseudomonas fluorescens 55, Pa 3-1, Pa 98 and Escherichia coli, transformed with pHIR11 harbouring a T3SS, and the phytopathogenic bacteria Erwinia amylovora, Dickeya solani and Xanthomonas campestris pv. campestris were transformed with the T3Es hsvG, hsvB, pthG and pseB, either individually or in pairs, and used to infect gypsophila and beet. Strikingly, all the tested nonpathogenic and phytopathogenic bacterial strains harbouring hsvG and pthG incited galls on gypsophila, whereas strains harbouring hsvB and pseB, with the exception of E. coli, incited galls on beet.
Topics: Bacterial Proteins; Bacterial Secretion Systems; Beta vulgaris; Host-Pathogen Interactions; Pantoea; Plant Tumors
PubMed: 31368647
DOI: 10.1111/mpp.12860 -
Animals : An Open Access Journal From... Mar 2022From a clinical point of view, knowledge of the commensal microbial flora of the conjunctival sac in healthy individuals proves to be of great importance. The aim of...
From a clinical point of view, knowledge of the commensal microbial flora of the conjunctival sac in healthy individuals proves to be of great importance. The aim of this study was to assess the presence and the composition of normal ocular microflora of healthy donkeys. Fourteen clinically healthy donkeys () participated in the study. After prior ophthalmological examination, which showed no abnormalities, a conjunctival swab was taken from each donkey from the right and left eye. Species-specific identification was based on a morphological assessment of bacterial colonies stained with the Gram technique, as well as on biochemical properties and the disk-diffusion method. Around 82% of samples were positive for bacteria cultivation; was the most prevalently detected species, followed by . In conclusion, our study made it possible to determine the commensal flora of the conjunctival sac in donkeys. The obtained results also showed discrepancies in the composition of the conjunctival sac flora of donkeys and horses, despite the geographical proximity of performed studies. Knowledge of the commensal conjunctival flora of donkeys is of great clinical importance due to their greater exposure to corneal damage and infections than horses.
PubMed: 35327153
DOI: 10.3390/ani12060756 -
Biofilm Dec 2022Conditions affecting biofilm formation differ among bacterial species and this presents a challenge to studying biofilms in the lab. This work leverages functionalized...
Conditions affecting biofilm formation differ among bacterial species and this presents a challenge to studying biofilms in the lab. This work leverages functionalized silanes to control surface chemistry in the study of early biofilm propagation, quantified with a semi-automated image processing algorithm. These methods support the study of sp. YR343, a gram-negative bacterium isolated from the poplar rhizosphere. We found that sp. YR343 does not readily attach to hydrophilic surfaces but will form biofilms with a "honeycomb" morphology on hydrophobic surfaces. Our image processing algorithm described here quantified the evolution of the honeycomb morphology over time, and found the propagation to display a logarithmic behavior. This methodology was repeated with a flagella-deficient mutant of sp. YR343 which resulted in reduced surface attachment. Quantifiable differences between WT and Δ biofilm morphologies were captured by the image processing algorithm, further demonstrating the insight gained from these methods.
PubMed: 36303845
DOI: 10.1016/j.bioflm.2022.100088 -
The Science of the Total Environment May 2023Pantoea dispersa is a Gram-negative bacterium that exists in a variety of environments and has potential in many commercial and agricultural applications, such as... (Review)
Review
Pantoea dispersa is a Gram-negative bacterium that exists in a variety of environments and has potential in many commercial and agricultural applications, such as biotechnology, environmental protection, soil bioremediation, and plant growth stimulation. However, P. dispersa is also a harmful pathogen to both humans and plants. This "double-edged sword" phenomenon is not uncommon in nature. To ensure survival, microorganisms respond to both environmental and biological stimuli, which could be beneficial or detrimental to other species. Therefore, to harness the full potential of P. dispersa, while minimizing potential harm, it is imperative to unravel its genetic makeup, understand its ecological interactions and underlying mechanisms. This review aims to provide a comprehensive and up-to-date overview of the genetic and biological characteristics of P. dispersa, in addition to potential impacts on plants and humans, as well as to provide insights into potential applications.
Topics: Humans; Biodegradation, Environmental; Pantoea; Soil; Agriculture; Plants
PubMed: 36801414
DOI: 10.1016/j.scitotenv.2023.162320 -
International Journal of Systematic and... Aug 2023A facultative anaerobic, Gram-stain-negative rod-shaped bacterium, designated R, was isolated from the faecal material of a rabbit (). The strain could not be identified...
A facultative anaerobic, Gram-stain-negative rod-shaped bacterium, designated R, was isolated from the faecal material of a rabbit (). The strain could not be identified using an MALDI Biotyper sirius CA System. The closest matches based on the Bruker library were members of the genera and . However, the score value was in the range of no organism identification possible. Based on pairwise of 16S rRNA gene sequence analysis, the isolate was found to be a member of the family . The highest sequence similarities were found to the sequences of LMG 26273 (98.7 %), NBRC 102595 (98.5 %) and 090008 (98.4 %). Phylogenetic and whole genome analysis demonstrated that strain R represents a novel species within the genus . The predominant cellular fatty acids of strain R were C and products present in summed feature 2 (C) aldehyde, summed feature 3 (C ω6 and/or Cω7) and summed feature 8 (C ω7 and/or C ω6). genome analysis showed the presence of enzymes required for production of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylserine. The G+C content determined from the genome was 54.94 mol %. Based on biochemical, phylogenetic, genotypic and chemotaxonomic criteria, the isolate represents a novel species of the genus for which the name sp. nov. is proposed. The type strain is strain R (=CCUG 76269=ATCC TSD-291).
Topics: Animals; Rabbits; Fatty Acids; Phospholipids; Pantoea; Ubiquinone; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Base Composition; DNA, Bacterial; Bacterial Typing Techniques
PubMed: 37535055
DOI: 10.1099/ijsem.0.005968