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The ISME Journal Mar 2022Trophic interactions play a central role in driving microbial community assembly and function. In gut or soil ecosystems, successful inoculants are always facilitated by...
Trophic interactions play a central role in driving microbial community assembly and function. In gut or soil ecosystems, successful inoculants are always facilitated by efficient colonization; however, the metabolite exchanges between inoculants and resident bacteria are rarely studied, particularly in the rhizosphere. Here, we used bioinformatic, genetic, transcriptomic, and metabonomic analyses to uncover syntrophic cooperation between inoculant (Bacillus velezensis SQR9) and plant-beneficial indigenous Pseudomonas stutzeri in the cucumber rhizosphere. We found that the synergistic interaction of these two species is highly environmental dependent, the emergence of syntrophic cooperation was only evident in a static nutrient-rich niche, such as pellicle biofilm in addition to the rhizosphere. Our results identified branched-chain amino acids (BCAAs) biosynthesis pathways are involved in syntrophic cooperation. Genome-scale metabolic modeling and metabolic profiling also demonstrated metabolic facilitation among the bacterial strains. In addition, biofilm matrix components from Bacillus were essential for the interaction. Importantly, the two-species consortium promoted plant growth and helped plants alleviate salt stress. In summary, we propose a mechanism in which synergic interactions between a biocontrol bacterium and a partner species promote plant health.
Topics: Bacillus; Microbiota; Plant Roots; Pseudomonas stutzeri; Rhizosphere; Soil Microbiology
PubMed: 34593997
DOI: 10.1038/s41396-021-01125-3 -
Infectious Disease Reports Dec 2020bacteria are widespread pathogens that account for considerable infections with significant morbidity and mortality, especially in hospitalized patients. The genus... (Review)
Review
bacteria are widespread pathogens that account for considerable infections with significant morbidity and mortality, especially in hospitalized patients. The genus contains a large number of species; however, the majority of infections are caused by , infections by other species are less reported. is a ubiquitous Gram-negative bacterium that has been reported as a causative agent of some infections, particularly in immunocompromised patients but has rarely been reported as a cause of infective endocarditis. Here, we report a case of a 55-year-old female with no significant medical history who presented with exertional dyspnea, productive cough, and fever. She was diagnosed as a case of acute anterior ST myocardial infarction, underwent double valve replacement surgery, and was found to have infective endocarditis caused by .
PubMed: 33276629
DOI: 10.3390/idr12030020 -
Frontiers in Microbiology 2021is a species complex with extremely broad phenotypic and genotypic diversity. However, very little is known about its diversity, taxonomy and phylogeny at the genomic...
is a species complex with extremely broad phenotypic and genotypic diversity. However, very little is known about its diversity, taxonomy and phylogeny at the genomic scale. To address these issues, we systematically and comprehensively defined the taxonomy and nomenclature for this species complex and explored its genetic diversity using hundreds of sequenced genomes. By combining average nucleotide identity (ANI) evaluation and phylogenetic inference approaches, we identified 123 complex genomes covering at least six well-defined species among all sequenced genomes; of these, 25 genomes represented novel members of this species complex. ANI values of ≥∼95% and digital DNA-DNA hybridization (dDDH) values of ≥∼60% in combination with phylogenomic analysis consistently and robustly supported the division of these strains into 27 genomovars (most likely species to some extent), comprising 16 known and 11 unknown genomovars. We revealed that 12 strains had mistaken taxonomic assignments, while 16 strains without species names can be assigned to the species level within the species complex. We observed an open pan-genome of the complex comprising 13,261 gene families, among which approximately 45% gene families do not match any sequence present in the COG database, and a large proportion of accessory genes. The genome contents experienced extensive genetic gain and loss events, which may be one of the major mechanisms driving diversification within this species complex. Surprisingly, we found that the ectoine biosynthesis gene cluster () was present in all genomes of species complex strains but distributed at very low frequency (43 out of 9548) in other genomes, suggesting a possible origin of the ancestors of species complex in high-osmolarity environments. Collectively, our study highlights the potential of using whole-genome sequences to re-evaluate the current definition of the complex, shedding new light on its genomic diversity and evolutionary history.
PubMed: 35095786
DOI: 10.3389/fmicb.2021.755874 -
Frontiers in Microbiology 2022Soil salinity is one of the most important abiotic factors limiting plant productivity. The aim of this study was to determine the effect of selected halotolerant plant...
Soil salinity is one of the most important abiotic factors limiting plant productivity. The aim of this study was to determine the effect of selected halotolerant plant growth-promoting endophytes (PGPEs, ISE12 and CSE9) on the growth parameters of barley (), lettuce (), and sunflower () cultivated under salt stress conditions. A negative effect of two higher tested salinities (150 and 300 mM NaCl) was observed on the growth parameters of all investigated plants, including germination percentage and index (decreasing compared to the non-saline control variant in the ranges 5.3-91.7 and 13.6-90.9%, respectively), number of leaves (2.2-39.2%), fresh weight (24.2-81.6%); however, differences in salt stress tolerance among the investigated crops were observed ( > > ). Our data showed that the most crucial traits affected by endophyte inoculation under salt stress were chlorophyll concentration, leaf development, water storage, root development, and biomass accumulation. Thus, the influence of endophytes was species specific. CSE9 promoted the growth of all tested plant species and could be considered a universal PGPEs for many plant genotypes cultivated under saline conditions (e.g., increasing of fresh weight compared to the non-inoculated control variant of barley, lettuce, and sunflower in the ranges 11.4-246.8, 118.9-201.2, and 16.4-77.7%, respectively). ISE12 stimulated growth and mitigated salinity stress only in the case of barley. Bioaugmentation of crops with halotolerant bacterial strains can alleviate salt stress and promote plant growth; however, the selection of compatible strains and the verification of universal plant stress indicators are the key factors.
PubMed: 35350624
DOI: 10.3389/fmicb.2022.788893 -
Microorganisms Jan 2023Illite is a widely distributed clay mineral with huge reserves in Earth's crust, but its effect on heavy oil biodegradation is rarely reported. This study made an...
Illite is a widely distributed clay mineral with huge reserves in Earth's crust, but its effect on heavy oil biodegradation is rarely reported. This study made an investigation of the interactions between illite and a -heavy oil complex (HO). Results showed that, although illite exerted a negative effect on degrading heavy oil by inhibiting the biodegradation of 64 saturated hydrocarbons (SHs) and 50 aromatic hydrocarbons (AHs), it selectively stimulated the biodegradation of 45 AHs with a specific structure, and its biogenic kaolinization at room temperature (35 °C) and pressure (1 atm) was observed in HO for the first time. The finding points out for the first time that, in HO, illite may change the quasi-sequential of AHs biodegradation of heavy oil, as well as its kaolinization without clay intermediate.
PubMed: 36838295
DOI: 10.3390/microorganisms11020330 -
Analytical Chemistry Aug 2023Small proteins of around 50 aa in length have been largely overlooked in genetic and biochemical assays due to the inherent challenges with detecting and characterizing...
Small proteins of around 50 aa in length have been largely overlooked in genetic and biochemical assays due to the inherent challenges with detecting and characterizing them. Recent discoveries of their critical roles in many biological processes have led to an increased recognition of the importance of small proteins for basic research and as potential new drug targets. One example is CcoM, a 36 aa subunit of the -type oxidase that plays an essential role in adaptation to oxygen-limited conditions in , a model for the clinically relevant, opportunistic pathogen . However, as no comprehensive data were available in , we devised an integrated, generic approach to study small proteins more systematically. Using the first complete genome as basis, we conducted bottom-up proteomics analyses and established a digest-free, direct-sequencing proteomics approach to study cells grown under aerobic and oxygen-limiting conditions. Finally, we also applied a proteogenomics pipeline to identify missed protein-coding genes. Overall, we identified 2921 known and 29 novel proteins, many of which were differentially regulated. Among 176 small proteins 16 were novel. Direct sequencing, featuring a specialized precursor acquisition scheme, exhibited advantages in the detection of small proteins with higher (up to 100%) sequence coverage and more spectral counts, including sequences with high proline content. Three novel small proteins, uniquely identified by direct sequencing and not conserved beyond , were predicted to form an operon with a conserved protein and may represent genes. These data demonstrate the power of this combined approach to study small proteins in and show its potential for other prokaryotes.
Topics: Pseudomonas stutzeri; Proteomics; Proteogenomics; Pseudomonas aeruginosa; Oxygen
PubMed: 37535005
DOI: 10.1021/acs.analchem.3c00676 -
Revista Chilena de Infectologia :... Aug 2020
Topics: Pseudomonas stutzeri
PubMed: 33399664
DOI: 10.4067/S0716-10182020000400443 -
PloS One 2023Pollution by lead (Pb) is an environmental and health threat due to the severity of its toxicity. Microbial bioremediation is an eco-friendly technique used to remediate...
Pollution by lead (Pb) is an environmental and health threat due to the severity of its toxicity. Microbial bioremediation is an eco-friendly technique used to remediate contaminated soils. This present study was used to evaluate the effect of two bacterial strains isolated and identified from Bizerte lagoon: Cupriavidus metallidurans LBJ (C. metallidurans LBJ) and Pseudomonas stutzeri LBR (P. stutzeri LBR) on the rate of depollution of soil contaminated with Pb from Tunisia. To determine this effect, sterile and non-sterile soil was bioaugmented by P. stutzeri LBR and C. metallidurans LBJ strains individually and in a mixture for 25 days at 30°C. Results showed that the bioaugmentation of the non-sterile soil by the mixture of P. stutzeri LBR and C. metallidurans LBJ strains gave the best rate of reduction of Pb of 71.02%, compared to a rate of 58.07% and 46.47% respectively for bioaugmentation by the bacterial strains individually. In the case of the sterile soil, results showed that the reduction rate of lead was in the order of 66.96% in the case of the mixture of the two bacterial strains compared with 55.66% and 41.86% respectively for the addition of the two strains individually. These results are confirmed by analysis of the leachate from the sterile and non-sterile soil which showed an increase in the mobility and bioavailability of Pb in soil. These promising results offer another perspective for a soil bioremediation bioprocess applying bacterial bioremediation.
Topics: Pseudomonas stutzeri; Biodegradation, Environmental; Soil; Lead; Cupriavidus
PubMed: 37319245
DOI: 10.1371/journal.pone.0284120 -
Microbiology and Molecular Biology... Jun 2006Pseudomonas stutzeri is a nonfluorescent denitrifying bacterium widely distributed in the environment, and it has also been isolated as an opportunistic pathogen from... (Review)
Review
Pseudomonas stutzeri is a nonfluorescent denitrifying bacterium widely distributed in the environment, and it has also been isolated as an opportunistic pathogen from humans. Over the past 15 years, much progress has been made in elucidating the taxonomy of this diverse taxonomical group, demonstrating the clonality of its populations. The species has received much attention because of its particular metabolic properties: it has been proposed as a model organism for denitrification studies; many strains have natural transformation properties, making it relevant for study of the transfer of genes in the environment; several strains are able to fix dinitrogen; and others participate in the degradation of pollutants or interact with toxic metals. This review considers the history of the discovery, nomenclatural changes, and early studies, together with the relevant biological and ecological properties, of P. stutzeri.
Topics: Biology; Drug Resistance, Bacterial; Ecology; Genes, Bacterial; Genetic Variation; Phylogeny; Pseudomonas stutzeri
PubMed: 16760312
DOI: 10.1128/MMBR.00047-05 -
Frontiers in Microbiology 2018Mercury-mediated toxicity remains one of the greatest barriers against microbial survival, even though bacterial resistance to mercury compounds can occur. However, the...
Mercury-mediated toxicity remains one of the greatest barriers against microbial survival, even though bacterial resistance to mercury compounds can occur. However, the genetic and physiological adaptations of bacteria to mercury stress still remains unclear. Here, we show that the marine bacterium 273 is resistant to 50 μM Hg and removes up to 94% Hg from culture. Using gene homologous recombination and complementation, we show that genes encoding Hg-transport proteins MerT, MerP, the mercuric reductase MerA and the regulatory protein MerD are essential for bacterial mercuric resistance when challenged with Hg. Further, mercury stress inhibits flagellar development, motility, chemotaxis and biofilm formation of 273, which are verified by transcriptomic and physiological analyses. Surprisingly, we discover that MerF, a previously reported Hg-transporter, determines flagellar development, motility and biofilm formation in 273 by genetic and physiological analyses. Our results strongly indicate that MerF plays an integral role in 273 to develop physiological responses to mercury stress. Notably, MerF homologs are also prevalent in different human pathogens. Using this unique target may provide novel strategies to control these pathogenic bacteria, given the role of MerF in flagella and biofilm formation. In summary, our data provide an original report on MerF in bacterial physiological development and suggest that the in marine bacteria has evolved through progressive, sequential recruitment of novel functions over time.
PubMed: 29675016
DOI: 10.3389/fmicb.2018.00682