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Archives of Oral Biology Oct 2011The aim was to evaluate the presence of Staphylococcus spp., Enterobacteriaceae and Pseudomonadaceae in the oral cavities of HIV-positive patients. Forty-five... (Comparative Study)
Comparative Study
The aim was to evaluate the presence of Staphylococcus spp., Enterobacteriaceae and Pseudomonadaceae in the oral cavities of HIV-positive patients. Forty-five individuals diagnosed as HIV-positive by ELISA and Western-blot, and under anti-retroviral therapy for at least 1 year, were included in the study. The control group constituted 45 systemically healthy individuals matched to the HIV patients to gender, age and oral conditions. Oral rinses were collected and isolates were identified by API system. Counts of microorganisms from HIV and control groups were compared statistically by a Mann-Whitney test (α=5%). The percentages of individuals positive for staphylococci were similar between the groups (p=0.764), whereas for Gram-negative rods, a higher percentage was observed amongst HIV-positive (p=0.001). There was no difference in Staphylococcus counts between HIV and control groups (p=0.1008). Counts were lower in the oral cavities of patients with low viral load (p=0.021), and no difference was observed in relation to CD4 counts (p=0.929). Staphylococcus aureus was the most frequently isolated species in HIV group, and Staphylococcus epidermidis was the prevalent species in the control group. Significantly higher numbers of enteric bacteria and pseudomonas were detected in the oral cavities of the HIV group than in the control (p=0.0001). Enterobacter cloacae was the most frequently isolated species in both groups. Counts of enteric bacteria and pseudomonas were significantly lower in patients with low CD4 counts (p=0.011); however, there was no difference relating to viral load. It may be concluded that HIV group showed greater species diversity and a higher prevalence of Enterobacteriaceae/Pseudomonadaceae.
Topics: Adult; Aged; Anti-Retroviral Agents; Antiretroviral Therapy, Highly Active; Bacterial Load; Brazil; CD4 Lymphocyte Count; Case-Control Studies; Enterobacter cloacae; Enterobacteriaceae; Female; HIV Protease Inhibitors; HIV Seropositivity; Humans; Klebsiella oxytoca; Male; Middle Aged; Mouth; Pseudomonadaceae; Pseudomonas; Staphylococcus; Staphylococcus aureus; Staphylococcus epidermidis; Viral Load; Young Adult
PubMed: 21420663
DOI: 10.1016/j.archoralbio.2011.02.016 -
International Journal of Systematic and... Sep 2021Strain F2A, isolated from the cricket , was subjected to a polyphasic taxonomic characterization. Cells of the strain were rod-shaped, Gram-stain-negative and catalase-...
Strain F2A, isolated from the cricket , was subjected to a polyphasic taxonomic characterization. Cells of the strain were rod-shaped, Gram-stain-negative and catalase- and oxidase-positive. It did not assimilate any carbohydrates. The strain's 16S rRNA gene sequence showed highest similarity to QZS01 (96.4 %). The next highest similarity values were found to representatives of related genera (<93 %). The genome size of strain F2A was 3.2 Mbp and the G+C content was 36.4 mol%. Average nucleotide identity values based on blast and MUMmer and average amino acid identity values between strain F2A and QZS01 were 74.29/74.43, 83.88 and 74.70 %, respectively. The quinone system predominantly contained ubiquinone Q-8. In the polar lipid profile, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and an unidentified phospholipid were detected. The polyamine pattern consisted of the major compounds putrescine and spermidine. Major fatty acids were C ω7 and C and the hydroxyl acids were C 3-OH, C 2-OH and C 3-OH. The diagnostic diamino acid of the peptidoglycan was -diaminopimelic acid. Due to its association with the only species of the genus but its distinctness from we here propose the novel species sp. nov. F2A (=CCM 9136=LMG 32211).
Topics: Animals; Bacterial Typing Techniques; Base Composition; DNA, Bacterial; Diaminopimelic Acid; Fatty Acids; Gryllidae; Nucleic Acid Hybridization; Peptidoglycan; Phospholipids; Phylogeny; Pseudomonadaceae; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Ubiquinone
PubMed: 34516367
DOI: 10.1099/ijsem.0.004997 -
The Journal of General Physiology May 2017A new study explains 's strong resistance to osmotic down-shock.
A new study explains 's strong resistance to osmotic down-shock.
Topics: Pseudomonas; Pseudomonas aeruginosa
PubMed: 28424228
DOI: 10.1085/jgp.201711799 -
Molecular Plant Pathology Dec 2012Pseudomonas savastanoi pv. savastanoi is the causal agent of olive (Olea europaea) knot disease and an unorthodox member of the P. syringae complex, causing aerial... (Review)
Review
UNLABELLED
Pseudomonas savastanoi pv. savastanoi is the causal agent of olive (Olea europaea) knot disease and an unorthodox member of the P. syringae complex, causing aerial tumours instead of the foliar necroses and cankers characteristic of most members of this complex. Olive knot is present wherever olive is grown; although losses are difficult to assess, it is assumed that olive knot is one of the most important diseases of the olive crop. The last century witnessed a large number of scientific articles describing the biology, epidemiology and control of this pathogen. However, most P. savastanoi pv. savastanoi strains are highly recalcitrant to genetic manipulation, which has effectively prevented the pathogen from benefitting from the scientific progress in molecular biology that has elevated the foliar pathogens of the P. syringae complex to supermodels. A number of studies in recent years have made significant advances in the biology, ecology and genetics of P. savastanoi pv. savastanoi, paving the way for the molecular dissection of its interaction with other nonpathogenic bacteria and their woody hosts. The selection of a genetically pliable model strain was soon followed by the development of rapid methods for virulence assessment with micropropagated olive plants and the analysis of cellular interactions with the plant host. The generation of a draft genome of strain NCPPB 3335 and the closed sequence of its three native plasmids has allowed for functional and comparative genomic analyses for the identification of its pathogenicity gene complement. This includes 34 putative type III effector genes and genomic regions, shared with other pathogens of woody hosts, which encode metabolic pathways associated with the degradation of lignin-derived compounds. Now, the time is right to explore the molecular basis of the P. savastanoi pv. savastanoi-olive interaction and to obtain insights into why some pathovars like it necrotic and why some like it knot.
SYNONYMS
Pseudomonas syringae pv. savastanoi.
TAXONOMY
Kingdom Bacteria; Phylum Proteobacteria; Class Gammaproteobacteria; Family Pseudomonadaceae; Genus Pseudomonas; included in genomospecies 2 together with at least P. amygdali, P. ficuserectae, P. meliae and 16 other pathovars from the P. syringae complex (aesculi, ciccaronei, dendropanacis, eriobotryae, glycinea, hibisci, mellea, mori, myricae, phaseolicola, photiniae, sesami, tabaci, ulmi and certain strains of lachrymans and morsprunorum); when a formal proposal is made for the unification of these bacteria, the species name P. amygdali would take priority over P. savastanoi.
MICROBIOLOGICAL PROPERTIES
Gram-negative rods, 0.4-0.8 × 1.0-3.0 μm, aerobic. Motile by one to four polar flagella, rather slow growing, optimal temperatures for growth of 25-30 °C; oxidase negative, arginine dihydrolase negative; elicits the hypersensitive response on tobacco; most isolates are fluorescent and levan negative, although some isolates are nonfluorescent and levan positive.
HOST RANGE
P. savastanoi pv. savastanoi causes tumours in cultivated and wild olive and ash (Fraxinus excelsior). Although strains from olive have been reported to infect oleander (Nerium oleander), this is generally not the case; however, strains of P. savastanoi pv. nerii can infect olive. Pathovars fraxini and nerii are differentiated from pathovar savastanoi mostly in their host range, and were not formally recognized until 1996. Literature before about 1996 generally names strains of the three pathovars as P. syringae ssp. savastanoi or P. savastanoi ssp. savastanoi, contributing to confusion on the host range and biological properties.
DISEASE SYMPTOMS
Symptoms of infected trees include hyperplastic growths (tumorous galls or knots) on the stems and branches of the host plant and, occasionally, on leaves and fruits.
EPIDEMIOLOGY
The pathogen can survive and multiply on aerial plant surfaces, as well as in knots, from where it can be dispersed by rain, wind, insects and human activities, entering the plant through wounds. Populations are very unevenly distributed in the plant, and suffer drastic fluctuations throughout the year, with maximum numbers of bacteria occurring during rainy and warm months. Populations of P. savastanoi pv. savastanoi are normally associated with nonpathogenic bacteria, both epiphytically and endophytically, and have been demonstrated to form mutualistic consortia with Erwinia toletana and Pantoea agglomerans, which could result in increased bacterial populations and disease symptoms.
DISEASE CONTROL
Based on preventive measures, mostly sanitary and cultural practices. Integrated control programmes benefit from regular applications of copper formulations, which should be maintained for at least a few years for maximum benefit. Olive cultivars vary in their susceptibility to olive knot, but there are no known cultivars with full resistance to the pathogen.
USEFUL WEBSITES
http://www.pseudomonas-syringae.org/; http://genome.ppws.vt.edu/cgi-bin/MLST/home.pl; ASAP access to the P. savastanoi pv. savastanoi NCPPB 3335 genome sequence https://asap.ahabs.wisc.edu/asap/logon.php.
Topics: Adaptation, Physiological; Genome, Bacterial; Host-Pathogen Interactions; Humans; Olea; Plant Diseases; Pseudomonas
PubMed: 22805238
DOI: 10.1111/j.1364-3703.2012.00816.x -
Journal of Bacteriology Sep 1952
Topics: Humans; Pseudomonas; Pseudomonas stutzeri
PubMed: 12980914
DOI: 10.1128/jb.64.3.413-422.1952 -
Neurology India 2018
Topics: Adult; Bacterial Infections; Humans; Male; Pseudomonadaceae; Ventriculoperitoneal Shunt
PubMed: 29323021
DOI: 10.4103/0028-3886.222883 -
Molecular Plant Pathology Jan 2022Pseudomonas viridiflava is a gram-negative pseudomonad that is phylogenetically placed within the Pseudomonas syringae species complex. P. viridiflava has a wide host...
UNLABELLED
Pseudomonas viridiflava is a gram-negative pseudomonad that is phylogenetically placed within the Pseudomonas syringae species complex. P. viridiflava has a wide host range and causes a variety of symptoms in different plant parts, including stems, leaves, and blossoms. Outside of its role as a pathogen, P. viridiflava also exists as an endophyte, epiphyte, and saprophyte. Increased reports of P. viridiflava causing disease on new hosts in recent years coincide with increased research on its genetic variability, virulence, phylogenetics, and phenotypes. There is high variation in its core genome, virulence factors, and phenotypic characteristics. The main virulence factors of this pathogen include the enzyme pectate lyase and virulence genes encoded within one or two pathogenicity islands. The delineation of P. viridiflava in the P. syringae complex has been investigated using several molecular approaches. P. viridiflava comprises its own species, within the complex. While seemingly an outsider to the complex as a whole due to differences in the core genome and virulence genes, low average nucleotide identity to other of P. syringae complex members, and some phenotypic traits, it remains as part of the complex. Defining phylogenetic, phenotypic, and genomic characteristics of P. viridiflava in comparison to other P. syringae members is important to understanding this pathogen and for the development of disease resistance and management practices.
TAXONOMY
Kingdom Bacteria; Phylum Proteobacteria; Class Gammaproteobacteria; Family Pseudomonadaceae; Genus Pseudomonas; Species Pseudomonas syringae species complex, Genomospecies 6, Phylogroup 7 and 8.
MICROBIOLOGICAL PROPERTIES
Gram-negative, fluorescent, aerobic, motile, rod-shaped, oxidase negative, arginine dihydrolase negative, levan production negative (or positive), potato rot positive (or negative), tobacco hypersensitivity positive.
GENOME
There are two complete genomes, five chromosome-level genomes, and 1,540 genomes composed of multiple scaffolds of P. viridiflava available in the National Center for Biotechnology Information Genome database. The median total length of these assemblies is 5,975,050 bp, the median number of protein coding genes is 5,208, and the median G + C content is 59.3%.
DISEASE SYMPTOMS
P. viridiflava causes a variety of disease symptoms, including spots, streaks, necrosis, rots, and more in above- and below-ground plant parts on at least 50 hosts.
EPIDEMIOLOGY
There have been several significant disease outbreaks on field and horticultural crops caused by P. viridiflava since the turn of the century. P. viridiflava has been reported as a pathogen, epiphyte, endophyte, and saprophyte. This species has been isolated from a variety of environmental sources, including asymptomatic wild plants, snow, epilithic biofilms, and icepacks.
Topics: Phylogeny; Plant Diseases; Pseudomonas; Pseudomonas syringae; Virulence
PubMed: 34463014
DOI: 10.1111/mpp.13133 -
Nature May 1991Infrared signals of microorganisms are highly specific fingerprint-like patterns that can be used for probing the identity of microorganisms. The simplicity and...
Infrared signals of microorganisms are highly specific fingerprint-like patterns that can be used for probing the identity of microorganisms. The simplicity and versatility of Fourier-transform infrared spectroscopy (FT-IR) makes it a versatile technique for rapid differentiation, classification, identification and large-scale screening at the subspecies level.
Topics: Fourier Analysis; Pseudomonas; Pseudomonas aeruginosa; Pseudomonas fluorescens; Spectrophotometry, Infrared
PubMed: 1902911
DOI: 10.1038/351081a0 -
Current Microbiology Dec 2021Azotobacter vinelandii is a motile bacterium that possesses an unusual pattern of peritrichous flagellation for members of the Pseudomonadaceae family. Unlike what has...
Azotobacter vinelandii is a motile bacterium that possesses an unusual pattern of peritrichous flagellation for members of the Pseudomonadaceae family. Unlike what has been reported for Pseudomonas spp. FleQ is not the master regulator of motility in A. vinelandii, this role is performed by FlhDC. Other factors involved in the regulation of motility are AlgU (σ) and CydR which act as negative regulators. In some members of the Enterobacteriaceae and Pseudomonadaceae families, the GacS/A-Rsm pathway is another important factor regulating motility. In the present study, the involvement of the GacS/A-Rsm pathway in regulating the motility of A. vinelandii was explored; we found that contrary to what has been reported for most of the strains studied of Pseudomonas species, GacS/A, through the Rsm system, positively controlled swimming motility. We show that the target of this regulation is the synthesis of flagella, which most likely occurs in an FlhDC-independent manner.
Topics: Azotobacter vinelandii; Bacterial Proteins; Flagella; Gene Expression Regulation, Bacterial; Humans
PubMed: 34905080
DOI: 10.1007/s00284-021-02695-3 -
Microbial Ecology Nov 2016Bacterial species exhibit biogeographical patterns like those observed in larger organisms. The distribution of bacterial species is driven by environmental selection...
Bacterial species exhibit biogeographical patterns like those observed in larger organisms. The distribution of bacterial species is driven by environmental selection through abiotic and biotic factors as well dispersal limitations. We asked whether interference competition, a biotic factor, could explain variability in habitat use by Pseudomonas species in the human home. To answer this question, we screened almost 8000 directional, pairwise interactions between 89 Pseudomonas strains including members of the Pseudomonas aeruginosa (n = 29), Pseudomonas fluorescens (n = 21), and Pseudomonas putida (n = 39) species groups for the presence of killing. This diverse set of Pseudomonas strains includes those isolated from several different habitats within the home environment and includes combinations of strains that were isolated from different spatial scales. The use of this strain set not only allowed us to analyze the commonality and phylogenetic scale of interference competition within the genus Pseudomonas but also allowed us to investigate the influence of spatial scale on this trait. Overall, the probability of killing was found to decrease with increasing phylogenetic distance, making it unlikely that interference competition accounts for previously observed differential habitat use among Pseudomonas species and species groups. Strikingly, conspecific P. aeruginosa killing accounted for the vast majority of the observed killing, and this killing was found to differ across the habitat type and spatial scale of the strains' isolation. These data suggest that interference competition likely plays a large role in the within-species dynamics of P. aeruginosa but not other household Pseudomonas species.
Topics: Bacteriocins; Ecosystem; Humans; Microbial Interactions; Phylogeny; Pseudomonas aeruginosa; Pseudomonas fluorescens; Pseudomonas putida; Pyocins; Residence Characteristics
PubMed: 26276409
DOI: 10.1007/s00248-015-0652-1