Entomomonas asaccharolytica sp. nov., isolated from Acheta domesticus.

Strain F2AT, isolated from the cricket Acheta domesticus, 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 Entomomonas moraniae QZS01T (96.4 %). The next highest similarity values were found to representatives of related genera (<93 %). The genome size of strain F2AT 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 F2AT and E. moraniae QZS01T 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 C18 : 1 ω7c and C16 : 0 and the hydroxyl acids were C12 : 0 3-OH, C14 : 0 2-OH and C14 : 0 3-OH. The diagnostic diamino acid of the peptidoglycan was meso-diaminopimelic acid. Due to its association with the only species of the genus Entomomonas but its distinctness from E. moraniae we here propose the novel species Entomomonas asaccharolytica sp. nov. F2AT (=CCM 9136T=LMG 32211T).

Classification of a Violacein-Producing Psychrophilic Group of Isolates Associated with Freshwater in Antarctica and Description of Rugamonas violacea sp. nov.

A group of 11 bacterial strains was isolated from streams and lakes located in a deglaciated northern part of James Ross Island, Antarctica. They were rod-shaped, Gram-stain-negative, motile, and catalase-positive and produced blue-violet-pigmented colonies on R2A agar. A polyphasic taxonomic approach based on 16S rRNA gene sequencing, whole-genome sequencing, automated ribotyping, repetitive element sequence-based PCR (rep-PCR), MALDI-TOF MS, fatty acid profile, chemotaxonomy analyses, and extensive biotyping was applied in order to clarify the taxonomic position of these isolates. Phylogenetic analysis based on the 16S rRNA gene indicated that all the isolates constituted a coherent group belonging to the genus Rugamonas. The closest relatives to the representative isolate P5900T were Rugamonas rubra CCM 3730T, Rugamonas rivuli FT103WT, and Rugamonas aquatica FT29WT, exhibiting 99.2%, 99.1%, and 98.6% 16S rRNA pairwise similarity, respectively. The average nucleotide identity and digital DNA-DNA hybridization values calculated from the whole-genome sequencing data clearly proved that P5900T represents a distinct Rugamonas species. The G+C content of genomic DNAs was 66.1 mol%. The major components in fatty acid profiles were summed feature 3 (C16:1ω7c/C16:1ω6c), C 16:0, and C12:0. The cellular quinone content contained exclusively ubiquinone Q-8. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. The polyamine pattern was composed of putrescine, 2-hydroxputrescine, and spermidine. IMPORTANCE Our polyphasic approach provides a new understanding of the taxonomy of novel pigmented Rugamonas species isolated from freshwater samples in Antarctica. The isolates showed considerable extracellular bactericidal secretions. The antagonistic activity of studied isolates against selected pathogens was proved by this study and implied the importance of such compounds' production among aquatic bacteria. The psychrophilic and violacein-producing species Roseomonas violacea may play a role in the diverse consortium among pigmented bacteria in the Antarctic water environment. Based on all the obtained results, we propose a novel species for which the name Rugamonas violacea sp. nov. is suggested, with the type strain P5900T (CCM 8940T; LMG 32105T). Isolates of R. violacea were obtained from different aquatic localities, and they represent the autochthonous part of the water microbiome in Antarctica.

Analysis of bacterial FAMEs using gas chromatography - vacuum ultraviolet spectroscopy for the identification and discrimination of bacteria.

The identification of microorganisms is very important in different fields and alternative methods are necessary for a rapid and simple identification. The use of fatty acids for bacterial identification is gaining attention as phenotypic characteristics are reflective of the genotype and are more easily analyzed. In this work, gas chromatography-vacuum ultraviolet spectroscopy (GC-VUV) was used to determine bacteria fatty acid methyl esters (FAMEs), to identify and discriminate different environmental bacteria based on their fatty acid profile. Microorganisms were grown in agar and their fatty acids extracted, saponified, and esterified before analysis. Unique FAME profiles were obtained for each microorganism mainly composed of branched, cyclopropane, hydroxy, saturated, and unsaturated fatty acid methyl esters. S. maltophilia showed a higher diversity of fatty acids while Bacillus species showed higher complexity in terms of branched-chain FAMEs, with several iso and anteiso forms. 12 different bacteria genera and 15 species were successfully differentiated based on their fatty acid profiles after performing PCA and cluster analysis. Some difficult to differentiate species, such as Bacillus sp., which are genetically very similar, were differentiated with the developed method.

Sputum microbiota in severe asthma patients: Relationship to eosinophilic inflammation.

BACKGROUND: Altered composition of airway microbiota has been reported in subjects suffering from asthma but its relation to eosinophilic phenotype is unclear. OBJECTIVE: To examine the relationship between sputum microbiota, asthma severity and inflammatory type in asthmatic subjects from Guangzhou, China. METHODS: Induced sputum samples were obtained from 49 non-smoking asthma patients, 25 severe and 24 non-severe, and 15 healthy subjects. Total DNA was amplified using primers specific for the V3-V5 hypervariable region of bacterial 16s rRNA and sequenced using the 454 GS FLX sequencer. Sequences were assigned to bacterial taxa by comparing them with 16s rRNA sequences in the Ribosomal Database Project. RESULTS: Sputum eosinophil counts were higher and FEV1 (% predicted) was lower in severe compared to non-severe asthmatics. There were no significant differences in operational taxonomic unit (OTU) numbers at the phylum level and in diversity scores between non-severe asthmatics and severe asthmatics, and healthy subjects. At the family level, Porphyromonadaceae was most abundant in healthy subjects whereas Pseudomonadaceae and Enterobacteriaceae were higher in severe asthmatics compared to non-severe asthmatics (p < 0.05). Actinomycetaceae was particularly abundant in eosinophilic asthma patients compared to non-eosinophilic asthma (p = 0.011). Bacteroidaceae was positively correlated with FEV1 in all subjects (r = 0.335, p < 0.01), whereas body mass index was negatively associated with the number of species observed (r = -0.3, p < 0.05). Principal component analysis confirmed the positive association of Actinomycetaceae and Enterobacteriaceae abundance with eosinophilic asthma. CONCLUSION: Patients with asthma have an altered airway microbiota, with specific bacteria associated with severe asthma and the eosinophilic inflammatory phenotype.

Rhizobacter profundi sp. nov., isolated from freshwater sediment.

Three bacterial strains, designated DS48-6-5T, DS48-6-7 and DS48-6-9, were isolated from a sediment sample taken from Daechung Reservoir (Republic of Korea) at a water depth of 48 m. Cells of the strains were Gram-stain-negative, aerobic, rod-shaped and motile with a single polar flagellum. Comparative 16S rRNA gene sequence studies showed that the three isolates had clear affiliation with Betaproteobacteria and the closest relatives were Rhizobacter bergeniae KCTC 32299T, Rhizobacter dauci DSM 11587T and Rhizobacter fulvus KCTC 12591T with 97.2-97.9 % 16S rRNA gene sequence similarities; the 16S rRNA gene sequence similarities between the three strains were 99.5-100 %. The only isoprenoid quinone of the three strains was ubiquinone-8, and the major fatty acids were summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) and C16 : 0. The G+C content of the genomic DNA of strains DS48-6-5T, DS48-6-7 and DS48-6-9 was 66.7, 67.0 and 66.8 mol%, respectively. DNA-DNA hybridization values of the novel strains with R. bergeniae KCTC 32299T, R. dauci DSM 11587T and R. fulvus KCTC 12591T were 19.3-48.5 %. Based on the evidence from this taxonomic study using a polyphasic approach, it is proposed that strains, DS48-6-5T, DS48-6-7 and DS48-6-9, represent a novel species of the genus Rhizobacter, for which the name Rhizobacter profundi sp. nov. is proposed. The type strain is DS48-6-5T ( = KCTC 42645T = NBRC 111169T).

Permianibacter aggregans gen. nov., sp. nov., a bacterium of the family Pseudomonadaceae capable of aggregating potential biofuel-producing microalgae.

A novel bacterial strain, capable of aggregating potential biofuel-producing microalgae, was isolated from the phycosphere of an algal culture and designated HW001(T). The novel bacterial strain was identified on the basis of its phylogenetic, genotypic, chemotaxonomic and phenotypic characteristics in this study. Cells were aerobic, Gram-negative rods. 16S rRNA gene-based phylogenetic analysis revealed that strain HW001(T) is affiliated with the family Pseudomonadaceae in the phylum Proteobacteria, but forms a distinct clade within this family. The DNA G+C content of strain HW001(T) was 55.4 mol%. The predominant cellular fatty acids were iso-C15:0, summed feature 9 (iso-C17:1ω9c), C16:0 and summed feature 3 (C16:1ω7c/C16:1ω6c). Q-8 was the main respiratory quinone. The polar lipid profile contained phosphatidylethanolamine, an unidentified aminophospholipid and some unidentified lipids. Based on the extensive polyphasic analysis, strain HW001(T) represents a novel species of a new genus in the family Pseudomonadaceae, for which the name Permianibacter aggregans gen. nov., sp. nov., is proposed. The type strain of the type species is HW001(T) ( = CICC 10856(T) = KCTC 32485(T)).

Enterobacteriaceae and pseudomonadaceae on the dorsum of the human tongue.

OBJECTIVE: The aim of this study was to correlate the presence of Enterobacteriaceae, Pseudomonadaceae, Moraxellaceae and Xanthomonadaceae on the posterior dorsum of the human tongue with the presence of tongue coating, gender, age, smoking habit and denture use. MATERIAL AND METHODS: Bacteria were isolated from the posterior tongue dorsum of 100 individuals in MacConkey agar medium and were identified by the API 20E system (Biolab-Mérieux). RESULTS: 43% of the individuals, presented the target microorganisms on the tongue dorsum, with greater prevalence among individuals between 40 and 50 years of age (p = 0.001) and non-smokers (p=0.0485). CONCLUSIONS: A higher prevalence of Enterobacteriaceae and Pseudomonadaceae was observed on the tongue dorsum of the individuals evaluated. There was no correlation between these species and the presence and thickness of tongue coating, gender and presence of dentures.

Enterobacteriaceae and pseudomonadaceae on the dorsum of the human tongue

OBJECTIVE: The aim of this study was to correlate the presence of Enterobacteriaceae, Pseudomonadaceae, Moraxellaceae and Xanthomonadaceae on the posterior dorsum of the human tongue with the presence of tongue coating, gender, age, smoking habit and denture use. MATERIAL AND METHODS: Bacteria were isolated from the posterior tongue dorsum of 100 individuals in MacConkey agar medium and were identified by the API 20E system (Biolab-Mérieux). RESULTS: 43 percent of the individuals, presented the target microorganisms on the tongue dorsum, with greater prevalence among individuals between 40 and 50 years of age (p = 0.001) and non-smokers (p=0.0485). CONCLUSIONS: A higher prevalence of Enterobacteriaceae and Pseudomonadaceae was observed on the tongue dorsum of the individuals evaluated. There was no correlation between these species and the presence and thickness of tongue coating, gender and presence of dentures.

Effect of ferritin overexpression in tobacco on the structure of bacterial and pseudomonad communities associated with the roots.

The genetic structures of total bacterial and pseudomonad communities were characterized in rhizosphere soil and rhizoplane+root tissues of tobacco wild type and a ferritin overexpressor transgenic line (P6) by a cultivation-independent method using directly extracted DNA at the end of three consecutive plant cultures. The structure of total bacterial communities was characterized by automated ribosomal intergenic spacer analysis (A-RISA), and that of pseudomonad communities was characterized by PCR-restriction fragment length polymorphism (PCR-RFLP) from DNA amplified with specific primers. The structure of total bacterial communities was significantly modified in the rhizosphere soil by the overaccumulation of iron in the tobacco transgenic P6 line at the first culture, to a lesser extent at the second culture, and not at all at the third culture. No significant difference was recorded between the total communities associated with the roots (rhizoplane+root tissues) of the two plant genotypes in any of the cultures. In contrast, the difference in pseudomonad structure between the two plant genotypes increased with successive culture at the root level, but was not detected at a significant level in the rhizosphere soil. The impact of iron overaccumulation by the tobacco transgenic P6 line on pseudomonads supports previous findings on the importance of iron competition among fluorescent pseudomonads.

Pseudomonads associated with midrib rot and soft rot of butterhead lettuce and endive.

During the past ten years, bacterial soft rot and midrib rot of glasshouse-grown butterhead lettuce (Lactuca sativa L. var. capitata) and field-grown endive (Cichorium endivia L.) has become increasingly common in the region of Flanders, Belgium. Severe losses and reduced market quality caused by bacterial rot represent an important economical threat for the production sector. Symptoms of midrib rot are a brownish rot along the midrib of one or more inner leaves, often accompanied by soft rot of the leaf blade. Twenty-five symptomatic lettuce and endive samples were collected from commercial growers at different locations in Flanders. Isolations of dominant bacterial colony types on dilution plates from macerated diseased tissue extracts yielded 282 isolates. All isolates were characterized by colony morphology and fluorescence on pseudomonas agar F medium, oxidase reaction, and soft rot ability on detached chicory leaves. Whole-cell fatty acid methyl esters profile analyses identified the majority of isolates (85%) as belonging to the Gammaproteobacteria, which included members of the family Enterobacteriaceae (14%) and of the genera Pseudomonas (73%), Stenotrophomonas (9%), and Acinetobacter (3%). Predominant bacteria were a diverse group of fluorescent Pseudomonas species. They were further differentiated based on the non-host hypersensitive reaction on tobacco and the ability to rot potato slices into 4 phenotypic groups: HR-/P- (57 isolates), HR-/P+ (54 isolates), HR+/P (16 isolates) and HR+/P+ (35 isolates). Artificial inoculation of suspensions of HR-, pectolytic fluorescent pseudomonads in the leaf midrib of lettuce plants produced various symptoms of soft rot, but they did not readily cause symptoms upon spray inoculation. Fluorescent pseudomonads with phenotype HR+ were consistently isolated from typical dark midrib rot symptoms, and selected isolates reproduced the typical midrib rot symptoms when spray-inoculated onto healthy lettuce plants.

Salivary secretion rate, yeast cells, and oral candidiasis in patients with acute leukemia.

Stimulated salivary secretion rate was repeatedly determined in 29 patients with acute leukemia during two periods of cytotoxic treatment in myelosuppressive doses. For comparison, the salivary secretion rate was studied in 83 healthy persons and in three other groups of hospitalized patients without malignant disorders. At the start of cytotoxic treatment the secretion rate in the patients with leukemia was lower than in healthy persons. The rate fell significantly after 1 to 3 days and later rose to the level seen in the healthy persons. Several interacting factors may have contributed to the decrease in salivary secretion rate, but the most important factor was probably the use of antiemetic drugs during the first 3 days of the study periods. No relationship was found between salivary secretion rate and the number of gram-negative rods found in the mouth. Patients with low salivary secretion rates had high numbers of yeast cells and more often oral candidiasis.

[The occurrence of legionella in dental units and the consequences for practice hygiene]. / Legionellen-Vorkommen in Dentaleinheiten und Konsequenzen für die Praxishygiene.

The objective of our investigation is to establish and explain the contamination of dental treatment units on the basis of a theoretical model, as well as to develop solutions to problems. In a first longitudinal study (6), facultatively pathogenic bacteria were identified in the operating water of dental units; the legionellae findings in screening were verified in a second longitudinal study with consideration of possible causal factors of bacteriological and parasitological nature. We took samples from the dental units and the water conduit system (cold and warm water in the dental surgery, cold water in front of and behind house internal accessory installations) in seven practices at ten measurement times over a period of ten weeks. Microbiological diagnostics were carried out with regard to the occurrence of legionellae, amoebae, pseudomonads and coliforms. The correlation between the metal content of the water and the occurrence of legionellae described in the literature caused us to determine the copper, zinc and iron content of the waters (according to standard German method, 1985). In addition, the physical-chemical parameters temperature, pH value, conductivity and oxidizability as well as the total hardness were determined. The findings in the first phase of the study could be confirmed both qualitatively and quantitatively in the second phase. However, a greater diversity of species was shown with regard to the occurrence of legionellae in connection with an enlarged sample. We were able to isolate free-living amoebae from all dental units, the identification of which was carried out in parallel to that of legionellae in the context of the second investigation (26). With a high variance of the contamination spectrum between the individual practices and the various units within each practice, generalization of the results is not possible; the findings are hence illustrated with examples from selected practices with consideration of the initial and interaction conditions.

Hexavalent chromium-resistant bacteria isolated from river sediments.

Hexavalent chromium [Cr(VI)] is a known carcinogen and mutagen; however, the actual mechanisms of Cr toxicity are unknown. Two approaches were used to isolate Cr(VI)-resistant bacteria from metal-contaminated river sediments. Diluted sediments were plated directly onto a peptone-yeast extract (PYE) medium containing 0 to 100 micrograms of Cr(VI) ml-1. Approximately 8.4 x 10(5) CFU g-1 were recovered on 0 microgram of Cr(VI) ml-1, whereas 4.0 x 10(2) CFU g-1 were recovered on PYE plus 100 micrograms of Cr(VI) ml-1. Alternatively, continuous culture enrichment techniques were employed using PYE and 100 micrograms Cr(VI) ml-1 input at dilution rates of 0.02 and 0.10 h-1. After six residence periods, 10(9) CFU were recovered on PYE agar containing 0 microgram of Cr(VI) ml-1 and 10(7) CFU on PYE agar plus 100 micrograms of Cr(VI) ml-1. Of 89 isolates obtained by direct plating onto PYE, 47% were resistant to 100 micrograms of Cr(VI) ml-1, and 29% were resistant to 250 micrograms of Cr(VI) ml-1. When the same isolates were plated onto PYE containing Cr(III), 88% were resistant to 100 micrograms ml-1 but only 2% were resistant to 250 micrograms ml-1. Cr, Co, Sb, and Zn were found in significantly higher concentrations at an industry-related contaminated site than at a site 11 km downstream. Total Cr in the sediments at the contaminated site averaged 586 micrograms (dry weight) g-1, and the downstream site averaged 71 micrograms (dry weight) g-1. The Cr recovered from acid-digested Ottawa River sediment samples was predominantly hexavalent. Five acid digestion procedures followed by atomic absorption spectroscopy were compared and found to be 30 to 70% efficient for recovery of Cr relative to neutron activation analysis. A population of aerobic, heterotrophic bacteria was recovered from sediments containing elevated levels of Cr.(ABSTRACT TRUNCATED AT 250 WORDS)

[Azomonas agilis in the surface water of the environs of Buenos Aires]. / Azomonas agilis en aguas superficiales de los alrededores de Buenos Aires.

In 1941, it was reported the presence of Azomonas agilis in rivers near Buenos Aires City. To our knowledge no other study has been carried out since then, so that the object of this paper was to investigate some characteristics of this organism and its possible influence on the nitrogen balance in waters. The isolation was performed by the plate method, using a mineral base for Azotobacter with different energy sources. Calcium malate appeared to be the best for Azomonas-like organisms. On pure cultures were performed tests to describe the main properties. All the organisms isolated had similar morphology, big cells 3 x 5 mu, individuals or sometimes in pairs, with intracellular granules and Gram negative. Cysts were not formed and motility was very intense in all cases. Physiologically they all were strictly aerobic, catalase positive and able to reduce acetylene so it was confirmed they belonged to the genus Azomonas. Some of them could use glucose and produced a water soluble green pigment, fluorescent under ultraviolet light which are the main characteristics of Azomonas agilis. Others lacked one of this properties but also were considered to be this species because they were very different from Azomonas insignis. One strain remained labelled only as Azomonas sp because it did not show characters of any of the two species. Estimations of bacterial density by most probable number method indicated that this was very low and by using a colorimetric determination for ethylene no nitrogenase activity could be detected in the river water, adding or not glucose even after 48 h of incubation.(ABSTRACT TRUNCATED AT 250 WORDS)

[Intestinal bacterial flora in patients with colopathies. Study of samples obtained by colonoscopy]. / Microbisme intestinal de sujets atteints de colopathies. Etude de prélèvements recueilis par coloscopie

This enquiry, the limits of which are easy to determine, permits one to note that in patients with chronic hemorrhagic colonic disease samples of digestive juice, carried, out at the level of the colonic mucosa, permit isolation of a large number of pseudomonadaceae, these bacteria are extremely various. A single patient may harbour 10 to 12 species. These bacteria, usually harmless, belong to the natural microbiocenoses, but they may under certain circumstances, increase in number and, according to Fabiani, induce severe symptoms or even be fatal. The mass of bacteria isolated and identified did not permit a study of bacterial sensitivity. The most seriously affected subjects clinically, usually had various bacteria which excludes the accusation of one species and eliminates any idea of bacterial specificity in the constitution of the syndromes observed. The disturbance seems to be a consequence of these chronic diseases and not the cause. In fact, no pathogenic germ was isolated, which one might consider to be responsible for the disease. Finally, it is wise to conclude that patients with irritable colon syndromes who formed part of this investigation, simply presented some imbalance in the bacterial flora which was sometimes very marked with a predominance of proteolytic Pseudomonas.