scholarly journals Mucispirillum schaedleri gen. nov., sp. nov., a spiral-shaped bacterium colonizing the mucus layer of the gastrointestinal tract of laboratory rodents

2005 ◽  
Vol 55 (3) ◽  
pp. 1199-1204 ◽  
Author(s):  
Bronwyn R. Robertson ◽  
Jani L. O'Rourke ◽  
Brett A. Neilan ◽  
Peter Vandamme ◽  
Stephen L. W. On ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
New Genus ◽  
Bacterial Species ◽  
Mucus Layer ◽  
Bacterial Isolates ◽  
New Genus And Species ◽  
Laboratory Rodents ◽  
Distinct Lineage ◽  
High Level

The mammalian gastrointestinal tract is covered by a layer of mucus that can harbour a range of bacterial species specifically adapted to colonize this ecological niche. Examination of 110 bacterial isolates cultivated from the gastrointestinal tract of 23 mice revealed the presence of a subgroup of 30 isolates that did not correspond genetically with genera commonly associated with this site, i.e. members of the ε-Proteobacteria such as Helicobacter and Campylobacter species. Instead this group of isolates was found to lie within the phylum Deferribacteres, a completely distinct lineage in the domain Bacteria. There was a high level of consensus in results obtained from the phenotypic and genotypic characterization of a number of the isolates, which showed they were distinct from other members of the Deferribacteres. As such, they are proposed to constitute a new genus and species, Mucispirillum schaedleri gen. nov., sp. nov. These organisms are anaerobic, Gram-negative, spiral-shaped rods with bipolar flagella. The type strain is HRI I17T (=ATCC BAA-1009T=ACM 5223T).

Characterization of Planktonic and Biofilm Communities of Day-of-Hatch Chicks Cecal Microflora and Their Resistance to Salmonella Colonization†

2009 ◽  
Vol 72 (5) ◽  
pp. 959-965 ◽  
Author(s):  
CYNTHIA L. SHEFFIELD ◽  
TAWNI L. CRIPPEN ◽  
KATHLEEN ANDREWS ◽  
ROY J. BONGAERTS ◽  
DAVID J. NISBET
Keyword(s):  
Microbial Community ◽  
Gastrointestinal Tract ◽  
Continuous Flow ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Bacterial Species ◽  
Serovar Typhimurium ◽  
Automated Ribotyping ◽  
Cecal Microflora ◽  
Planktonic Communities

Recent concerns about the use of antimicrobials in food animals have increased interest in the microbial ecology and biofilms within their gastrointestinal tract. This work used a continuous-flow chemostat system to model the microbial community within the ceca from day-of-hatch chicks and its ability to resist colonization by Salmonella enterica serovar Typhimurium. We characterized the biofilm and planktonic communities from five cultures by using automated ribotyping. Eight species from six different genera were identified. Overall, the planktonic communities were more diverse, with 40% of the cultures containing four or more bacterial species. Eighty percent of the biofilm communities contained only one or two species of bacteria. Enterococcus faecalis was the only species isolated from all communities. None of the resulting microbial communities was able to resist colonization by S. enterica serovar Typhimurium. This is the first study to provide a molecular-based characterization of the biofilm and planktonic communities found in day-of-hatch chicken cecal microflora cultures.

scholarly journals Characterization of a Diffusible Signaling Factor from Xylella fastidiosa

mBio ◽  
2013 ◽  
Vol 4 (1) ◽  
Author(s):  
Ellen D. Beaulieu ◽  
Michael Ionescu ◽  
Subhadeep Chatterjee ◽  
Kenji Yokota ◽  
Dirk Trauner ◽  
...  
Keyword(s):  
Cell Signaling ◽  
Unsaturated Fatty Acids ◽  
Xylella Fastidiosa ◽  
Bacterial Species ◽  
Content Type ◽  
Isolation And Characterization ◽  
High Level ◽  
Diffusible Signaling Factor ◽  
Cell Cell

ABSTRACTCell-cell signaling inXylella fastidiosahas been implicated in the coordination of traits enabling colonization in plant hosts as well as insect vectors. This cell density-dependent signaling has been attributed to a diffusible signaling factor (DSF) produced by the DSF synthase RpfF. DSF produced by related bacterial species are unsaturated fatty acids, but that ofX. fastidiosawas thought to be different from those of other taxa. We describe here the isolation and characterization of anX. fastidiosaDSF (XfDSF) as 2(Z)-tetradecenoic acid. This compound was isolated both from recombinantErwinia herbicolaexpressingX. fastidiosa rpfFand from anX. fastidiosa rpfCdeletion mutant that overproduces DSF. Since anrpfFmutant is impaired in biofilm formation and underexpresses the hemagglutinin-like protein-encoding geneshxfAandhxfB, we demonstrate that these traits can be restored by ca. 0.5 µMXfDSF but not by myristic acid, the fully saturated tetradecenoic acid. AphoA-basedX. fastidiosabiosensor that assesses DSF-dependent expression ofhxfAorhxfBrevealed a high level of molecular specificity of DSF signaling.IMPORTANCEX. fastidiosacauses diseases in many important plants, including grape, where it incites Pierce’s disease. Virulence ofX. fastidiosafor grape is coordinated by cell-cell signaling molecules, designated DSF (Diffusible Signaling Factor). Mutants blocked in DSF production are hypervirulent for grape, suggesting that virulence is suppressed upon DSF accumulation and that disease could be controlled by artificial elevation of the DSF level in plants. In this work, we describe the isolation of the DSF produced byX. fastidiosaand the verification of its biological activity as an antivirulence factor. We also have developedX. fastidiosaDSF biosensors to evaluate the specificity of cell-cell signaling to be investigated.

scholarly journals Phage–Bacteria Interactions in Potential Applications of Bacteriophage vB_EfaS-271 against Enterococcus faecalis

Viruses ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 318
Author(s):  
Gracja Topka-Bielecka ◽  
Bożena Nejman-Faleńczyk ◽  
Sylwia Bloch ◽  
Aleksandra Dydecka ◽  
Agnieszka Necel ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Mammalian Cells ◽  
Bacterial Infections ◽  
Phage Therapy ◽  
Bacterial Species ◽  
Resistant Bacteria ◽  
Bacterial Cells ◽  
Potential Applications ◽  
High Level

Phage therapy is one of main alternative option for antibiotic treatment of bacterial infections, particularly in the era of appearance of pathogenic strains revealing resistance to most or even all known antibiotics. Enterococcus faecalis is one of such pathogens causing serious human infections. In the light of high level of biodiversity of bacteriophages and specificity of phages to bacterial species or even strains, development of effective phage therapy depend, between others, on identification and characterization of a large collection of these viruses, including understanding of their interactions with host bacterial cells. Recently, isolation of molecular characterization of bacteriophage vB_EfaS-271, infecting E. faecalis strains have been reported. In this report, phage–host interactions are reported, including ability of vB_EfaS-271 to infect bacteria forming biofilms, efficiency of eliminating bacterial cells from cultures depending on multiplicity of infection (m.o.i.), toxicity of purified phage particles to mammalian cells, and efficiency of appearance of phage-resistant bacteria. The presented results indicate that vB_EfaS-271 can significantly decrease number of viable E. faecalis cells in biofilms and in liquid cultures and reveals no considerable toxicity to mammalian cells. Efficiency of formation of phage-resistant bacteria was dependent on m.o.i. and was higher when the virion-cell ratio was as high as 10 than at low (between 0.01 and 0.0001) m.o.i. values. We conclude that vB_EfaS-271 may be considered as a candidate for its further use in phage therapy.

Isolation and characterization of cellulolytic anaerobic fungi and associated mycoplasmas from the rumen of a steer fed a roughage diet

1990 ◽  
Vol 36 (7) ◽  
pp. 513-517 ◽  
Author(s):  
H. Kudo ◽  
K. D. Jakober ◽  
R. C. Phillippe ◽  
K.-J. Cheng ◽  
D. J. S. Barr ◽  
...  
Keyword(s):  
Key Words ◽  
New Genus ◽  
Anaerobic Fungi ◽  
Ecological Role ◽  
New Genus And Species ◽  
Fermentation Products ◽  
Isolation And Characterization ◽  
Neocallimastix Patriciarum

The isolation of 12 strains of cellulolytic fungi from the rumen of a roughage-fed steer is described. These represented three different genera, including one new genus and species (Orpinomyces bovis). The organisms were indistinguishable on the basis of fermentation products from cellulose, and their fermentation patterns were very similar to those of rumen fungi isolated in other countries. Mycoplasmas were found to be associated with 7 of the 12 isolates. The ecological role of the association of the mycoplasmas with rumen fungi is still unknown. Key words: Orpinomyces bovis, Piromyces communis, Neocallimastix patriciarum.

Loculosulcatispora thailandica gen. et sp. nov. (Sulcatisporaceae), saprobic on woody litter in Thailand

Phytotaxa ◽  
2020 ◽  
Vol 475 (2) ◽  
pp. 67-78
Author(s):  
GUANG-CONG REN ◽  
DHANUSHKA N. WANASINGHE ◽  
DE-PING WEI ◽  
JUTAMART MONKAI ◽  
ERANDI YASANTHIKA ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Type Species ◽  
New Genus ◽  
New Genus And Species ◽  
Protein Coding ◽  
Coding Regions ◽  
The Family ◽  
Distinct Lineage ◽  
Woody Litter

A new monotypic coelomycetous genus, Loculosulcatispora (type species L. thailandica) is introduced in Pleosporales from woody litter in Thailand. Phylogenetic analysis of combined non-translated loci (SSU, LSU, ITS) and protein-coding regions (tef1-α, rpb2) shows the genus is a distinct lineage in Sulcatisporaceae. Loculosulcatispora is distinguished from other genera in the family, by having 1-celled, oblong, hyaline, smooth-walled conidia with guttules. Comprehensive morphological descriptions and illustrations are provided for the new genus and species.

scholarly journals Microbiological Assessment of Poultry Feeds within Ilorin, Nigeria

2017 ◽  
Vol 9 (1) ◽  
pp. 34-39 ◽  
Author(s):  
Ismaila Olawale SULE ◽  
Israel Oluwatunmise ILORI
Keyword(s):  
Micrococcus Luteus ◽  
Bacterial Species ◽  
Bacterial Count ◽  
Fungal Species ◽  
Antibiotics Resistance ◽  
Bacterial Isolates ◽  
Poultry Feeds ◽  
Resistance Patterns ◽  
Staphylococcus Hominis ◽  
High Level

The poultry feeds were obtained from 20 different poultry pens and their microbial contents were assessed. The antibiotics resistance patterns of the bacterial isolates were also determined. The bacterial count ranged from 5.0 × 103 to 1.76 × 106 cfu/g while the fungal count ranged from 3.5 × 104 to 1.9 × 105 cfu/g. The bacterial species isolated were Streptococcus salivarius, Streptococcus pyogenes, Micrococcus luteus, Micrococcus varians, Micrococcus roseus, Staphylococcus aureus, Staphylococcus saprophyticus and Staphylococcus hominis, while the fungal species isolated were Saccharomyces cerevisisae, Fusarium oxysporum, Penicillium sp., Humicola grisea, Aspergillus fumigatus, Hansenula sp. and Humicola fuscoatra. All the bacterial isolates were resistant to ceftazidime and cefuroxime and all the isolates were resistant to at least three antibiotics. Ofloxacin produced the highest zone of inhibition, followed by gentamicin, and then erythromycin. The presence of some pathogenic microorganisms in the poultry feeds revealed high level of contaminations. It is recommended that poultry feeds should be made from good quality grains and it should be prevented from environmental or other contamination.

scholarly journals Study of an arsenic metabolizing bacteria from arsenic contaminated soil of Chandpur district, Bangladesh

2019 ◽  
Vol 8 (1) ◽  
pp. 57-65
Author(s):  
Roksana Khanam ◽  
Ripa Moni ◽  
Md Zahidul Islam ◽  
Md Morsaline Billah ◽  
Umme Salma Zohora ◽  
...  
Keyword(s):  
Contaminated Soil ◽  
Bacterial Species ◽  
Toxic Metal ◽  
Extracellular Enzyme ◽  
Bacterial Isolates ◽  
Toxic Heavy Metals ◽  
16S Rrna Sequence ◽  
Yeast Extract Mannitol ◽  
16S Rrna Sequence Analysis

Arsenic is a toxic metal found as inorganic oxyanion arsenate As(V) and arsenite As (III) species. The disposal of toxic heavy metals such as arsenic poses high risk to environment. The present study was undertaken to isolate arsenic-metabolizing bacteria from arsenic contaminated soil of Chandpur district, which is one of the most arsenic contaminated area in Bangladesh and later these bacteria were screened for their ability to metabolize arsenate. Out of ninety eight isolates, ten were found to be capable of metabolizing arsenic in Yeast Extract Mannitol (YEM) medium containing 2 mM arsenate at 37ºC. One of the bacterial isolates designated as I-25 was found to produce an extracellular enzyme which can reduce As(V) into As(III) and able to grow in presence of up to 500 mM arsenate. Subsequent molecular identification of this enzyme producing bacterial isolate using 16s rRNA sequence analysis was correlated with previously identified isolate as Bacillus aryabhatti. Further characterization of the enzyme showed that optimum pH of the extracellular enzyme by the bacterial species was 7 and optimum temperature for the enzyme activity was 60ºC. The bacterial isolates can be exploited for the study of possible bioremediation of arsenic contamination. Jahangirnagar University J. Biol. Sci. 8(1): 57-65, 2019 (June)

scholarly journals Muriphaeosphaeria galatellae gen. et sp. nov. in Phaeosphaeriaceae (Pleosporales)

Phytotaxa ◽  
2015 ◽  
Vol 227 (1) ◽  
pp. 55 ◽  
Author(s):  
Chayanard Phukhamsakda ◽  
Hiran A. Ariyawansa ◽  
Rungtiwa Phookamsak ◽  
Putarak Chomnunti ◽  
Timur S. Bulgakov ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
New Genus ◽  
Sequence Data ◽  
Wall Layer ◽  
Its Sequence ◽  
Monotypic Genus ◽  
New Genus And Species ◽  
The Family ◽  
Distinct Lineage ◽  
Thin Walled

Muriphaeosphaeria galatellae was collected from Galatella villosa in Russia and is introduced as a novel monotypic genus and species in the family Phaeosphaeriaceae (Pleosporales). Muriphaeosphaeria is distinct from other genera of the family Phaeosphaeriaceae by its unique suite of characters such as, superficial ascomata with an ascomatal wall comprising thin-walled brown cells, cellular pseudoparaphyses, muriform ascospores; and conidiomata with a thick hyaline inner wall layer producing cylindrical to subclavate, 1−3-transversely septate, brown conidia. The asexual morph of M. galatellae developed in cultures when grown on sterilized pine needles and bamboo pieces. A phylogenetic analysis based on combined LSU, SSU and ITS sequence data showed that M. galatellae forms a distinct lineage in Phaeosphaeriaceae. The new genus and species are introduced and compared with other taxa in the family.

scholarly journals Characterization of Defluviitalea saccharophila gen. nov., sp. nov., a thermophilic bacterium isolated from an upflow anaerobic filter treating abattoir wastewaters, and proposal of Defluviitaleaceae fam. nov.

2012 ◽  
Vol 62 (Pt_3) ◽  
pp. 550-555 ◽  
Author(s):  
Linda Jabari ◽  
Hana Gannoun ◽  
Jean-Luc Cayol ◽  
Moktar Hamdi ◽  
Guy Fauque ◽  
...  
Keyword(s):  
New Genus ◽  
Elemental Sulfur ◽  
Thermophilic Bacterium ◽  
New Genus And Species ◽  
Fermentation Products ◽  
Anaerobic Filter ◽  
Physiological Properties ◽  
Optimum Ph ◽  
Nitrate And Nitrite

A novel thermophilic, anaerobic, Gram-stain-positive, terminal-spore-forming bacterium was isolated from an upflow anaerobic filter treating abattoir wastewaters in Tunisia. This strain, designated LIND6LT2T, grew at 40–60 °C (optimum 50–55 °C) and at pH 6.0–8.5 (optimum pH 7.0–7.5). It did not require NaCl for growth, but tolerated it up to 2 %. Sulfate, thiosulfate, elemental sulfur, sulfite, nitrate and nitrite were not used as electron acceptors. Growth of LIND6LT2T was inhibited by sulfite (2 mM). Strain LIND6LT2T used cellobiose, glucose, mannose, maltose, mannitol, sucrose and xylose as electron donors. The main fermentation products from glucose metabolism were acetate, formate, butyrate and isobutyrate. The predominant cellular fatty acids were C16 : 0 (68.4 %) and C14 : 0 (8.3 %). The G+C content of the genomic DNA was 35.2 mol%. On the basis of its phylogenetic and physiological properties, a new genus and species, Defluviitalea saccharophila gen. nov., sp. nov., are proposed to accommodate strain LIND6LT2T, placed in Defluviitaleaceae fam. nov. within the phylum Firmicutes, class Clostridia, order Clostridiales. Strain LIND6LT2T ( = DSM 22681T  = JCM 16312T) is the type strain of Defluviitalea saccharophila, which itself is the type species of Defluviitalea.

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