The ColR/S two-component system is a conserved determinant of host association across Pseudomonas species

Members of the bacterial genus Pseudomonas form mutualistic, commensal and pathogenic associations with diverse hosts. The prevalence of host association across the genus suggests that symbiosis may be a conserved ancestral trait and that distinct symbiotic lifestyles may be more recently evolved. Here we show that the ColR/S two-component system, part of the Pseudomonas core genome, is functionally conserved between Pseudomonas aeruginosa and Pseudomonas fluorescens. Using plant rhizosphere colonization and virulence in a murine abscess model, we show that colR is required for commensalism with plants and virulence in animals. Comparative transcriptomics revealed that the ColR regulon has diverged between P. aeruginosa and P. fluorescens and deleting components of the ColR regulon revealed strain-specific, but not host specific, requirements for ColR-dependent genes. Collectively, our results suggest that ColR/S allows Pseudomonas to sense and respond to a host, but that the ColR-regulon has diverged between Pseudomonas strains with distinct lifestyles.

Genome Mining of Pseudomonas Species: Diversity and Evolution of Metabolic and Biosynthetic Potential

Microbial genome sequencing has uncovered a myriad of natural products (NPs) that have yet to be explored. Bacteria in the genus Pseudomonas serve as pathogens, plant growth promoters, and therapeutically, industrially, and environmentally important microorganisms. Though most species of Pseudomonas have a large number of NP biosynthetic gene clusters (BGCs) in their genomes, it is difficult to link many of these BGCs with products under current laboratory conditions. In order to gain new insights into the diversity, distribution, and evolution of these BGCs in Pseudomonas for the discovery of unexplored NPs, we applied several bioinformatic programming approaches to characterize BGCs from Pseudomonas reference genome sequences available in public databases along with phylogenetic and genomic comparison. Our research revealed that most BGCs in the genomes of Pseudomonas species have a high diversity for NPs at the species and subspecies levels and built the correlation of species with BGC taxonomic ranges. These data will pave the way for the algorithmic detection of species- and subspecies-specific pathways for NP development.

Biofilm Interaction Mapping and Analysis (BIMA) of Interspecific Interactions in Pseudomonas Co-culture Biofilms

Pseudomonas species are ubiquitous in nature and include numerous medically, agriculturally and technologically beneficial strains of which the interspecific interactions are of great interest for biotechnologies. Specifically, co-cultures containing Pseudomonas stutzeri have been used for bioremediation, biocontrol, aquaculture management and wastewater denitrification. Furthermore, the use of P. stutzeri biofilms, in combination with consortia-based approaches, may offer advantages for these processes. Understanding the interspecific interaction within biofilm co-cultures or consortia provides a means for improvement of current technologies. However, the investigation of biofilm-based consortia has been limited. We present an adaptable and scalable method for the analysis of macroscopic interactions (colony morphology, inhibition, and invasion) between colony-forming bacterial strains using an automated printing method followed by analysis of the genes and metabolites involved in the interactions. Using Biofilm Interaction Mapping and Analysis (BIMA), these interactions were investigated between P. stutzeri strain RCH2, a denitrifier isolated from chromium (VI) contaminated soil, and 13 other species of pseudomonas isolated from non-contaminated soil. One interaction partner, Pseudomonas fluorescens N1B4 was selected for mutant fitness profiling of a DNA-barcoded mutant library; with this approach four genes of importance were identified and the effects on interactions were evaluated with deletion mutants and mass spectrometry based metabolomics.

The Role of a Rapid Prevention of Ralstonia pickettii Growth during Dialysis in a Frail Patient

Ralstonia pickettii is an opportunistic bacillus found in Pseudomonas species, with the ability to induce systemic infections. We report the case of a 69-year-old man, with a clinical history of myeloma, Type IIdiabetes, renal failure (grade IV), and colon cancer, that developed a severe bacterial infection, with acute asthenia and a fever, that appeared at the end of dialysis. Using theMALDI-TOF technology, the bacillus Ralstonia pickettii was identified, and an antimicrobial treatment was quickly started with a rapid microbiological remission.

Pseudomonas Species Prevalence, Protein Analysis, and Antibiotic Resistance: An Evolving Public Health Challenge

Psychrotrophic Pseudomonas is one of the significant microbes that lead to putrefaction in chilled meat. One of the biggest problems in the detection of Pseudomonas is that several species are seemingly identical. Antibiotic resistance is an alternative considerable challenge worldwide. Therefore, this study was designed to apply an accurate technique for the discrepancy of Pseudomonas species and to study their resistance against various antimicrobials. A total of 320 chicken meat specimens were cultivated, and phenotypically recognized the isolated bacteria. Protein analysis was carried out for cultured isolates via Microflex LT. The resistance of Pseudomonas isolates was recorded through Vitek®ฏ 2 AST-GN83 cards. Overall, 69 samples were identified as Pseudomonas spp. and included 18 Pseudomonas lundensis (P. lundensis), 16 Pseudomonas fragi (P. fragi), 13 Pseudomonas oryzihabitans (P. oryzihabitans), 10 Pseudomonas stutzeri (P. stutzeri), 5 Pseudomonas fluorescens (P. fluorescens), 4 Pseudomonas putida (P. putida), and 3 Pseudomonas aeruginosa (P. aeruginosa) isolates. Microflex LT identified all Pseudomonas isolates (100%) correctly with a score value ≥2.00. PCA positively discriminated the identified isolates into various groups. The antimicrobial resistance levels against Pseudomonas isolates were 81.16% for nitrofurantoin, 71% for ampicillin and ampicillin/sulbactam, 65.22% for cefuroxime and ceftriaxone, 55% for aztreonam, and 49.28% for ciprofloxacin. The susceptibilities were 100% for cefotaxime, 98.55% for ceftazidime, 94.20% for each piperacillin/tazobactam and cefepime, 91.3% for cefazolin. In conclusion, chicken meat was found to be contaminated with different Pseudomonas spp., with high incidence rates of P. lundensis. Microflex LT is a potent tool for distinguishing Pseudomonads at the species level.

Are there bacterial bioprotectants besides Bacillus and Pseudomonas species?

This chapter discusses the taxonomy of non-Bacillus and Pseudomonas (NBP) bioprotectant strains, including enterobacteria, actinomycetes, Sphingomonas, Methylobacterium, Agrobacterium-Rhizobium and Lactobacillus. The chapter reviews their mechanisms of action against plant pathogens. Sources of isolates and methods of isolation are discussed in building strain collections. The chapter then reviews procedures for screening antagonistic bacteria candidates as bioprotectants using biochemical and molecular markers, including the example of lactic acid bacteria. The chapter then covers strain improvement to increase fitness and efficacy in the field through physiological and genetic manipulation. Since they are essential for commercial development, biosafety issues are discussed, followed by an overview of patented substances and commercialized products. The chapter concludes with a summary and future trends in research on non-Bacillus and Pseudomonas species.

Pseudomonas zeiradicis from corn and Pseudomonas soyae from soybean, two new Pseudomonas species and endophytes from agricultural crops

Two novel Pseudomonas species associated with healthy plants and other habitats are described from the United States. They are Pseudomonas zeiradicis strain PI116 from corn in Missouri, compost from Massachusetts, urban soil from Iowa and water of Lake Erie; and Pseudomonas soyae strain JL117 from soybean in Indiana and Wisconsin, and soil in Wyoming. No plant pathogenic strains are known for any of the novel species based on genome comparisons to assemblies in GenBank.

Xanthogranulomatous pyelonephritis infected with the Providencia stuartii: a case report and literature review

Background Xanthogranulomatous pyelonephritis (XGP) is a rare and severe chronic inflammatory disease of the renal parenchyma, which is most commonly associated with super-infections by bacteria such as E. coli, Proteus mirabilis, and occasionally Pseudomonas species. Case presentation Herein, we present a rare case of a patient with XGP infected with Providencia stuartii. Initially, the patient refused nephrectomy and underwent holmium laser lithotripsy and right ureteral stenting, followed by meropenem treatment of 7 days. Relapse occurred in the third month after discharge from the hospital, due to which she underwent a radical nephrectomy. Discussion The diagnosis of XGP is confirmed by histopathology. The standard treatment for XGP is antibiotic therapy and radical nephrectomy, but partial nephrectomy may be appropriate in select cases.

Isolation of Pseudomonas species from soil sample for production of Pyoverdine and evaluation of its potential as an antimicrobial agent

Pyoverdine, a fluorescent siderophore that have high- affinity for iron is produced by Pseudomonas putida and Pseudomonas aeruginosa that synthesizes it under iron-deficient growth conditions. Pseudomonas species are often encountered in diverse ecological habitats along side being censurable for nosocomial infections spread round the world. Due to these characteristics, there's a growing interest during this microbe for a spread of uses. One such is the production of Pyoverdine, it influences the uptake of iron, along with eliminating the limited iron availability condition. Pyoverdine is important for Pseudomonas putida and Pseudomonas aeruginosa to cause acute infections. Intense research and study led to the invention of Pyoverdines being a crucial source of chelating Iron. This study is predicated on Pyoverdine extracted from two different species of Pseudomonas which will act as an antimicrobial agent for various species including Escherichia coli and Staphylococcus aureus. The organism, i.e., Pseudomonas putida and Pseudomonas aeruginosa, were isolated from soil sample using medias like: Cetrimide media, King’s B media. It had been confirmed using primary biochemical tests, along side species level identification (MALDI - TOF). Isolation was followed by studying the antimicrobial activity of Pyoverdine on different organisms using antibiotics as standard for the same. Results for the tests were obtained, colonies were observed on specific media and zone of inhibition was observed on Muller Hinton plate. Comparative studies were carried out to find which organism used up Pyoverdine or Pyoverdine - Fe complex without using FeCl3 as sole standard source. Thus, these compounds can synergize with conventional antimicrobials, forming a simpler treatment with serving as a useful gizmo

The genomic context for aflatoxin B1-degrading Pseudomonas strains

The whole genomes of three strains were sequenced and annotated. COG (Clusters of Orthologous Groups) and GO (Gene Ontology) annotations of the protein-coding genes from three strains show a conservation of genome-wide protein functions in genus Pseudomonas. However, the AFB1-degrading strains HAI2 and HT3 harbor much more genes belonged to the pathway of xenobiotics biodegradation and metabolism than non-degrading strain 48. Besides, the enzyme families potentially involved in the AFB1 degradation of bacteria are more abundant in the two AFB1-degrading strains. A pan-genome profile was then formed by comparing the genomes against other reference genomes of the corresponding Pseudomonas species. Accordingly, a total of 1,528 genes were found to be specific in AFB1-degrading strains, and 65 genes of them are related to oxidoreductase activity.