scholarly journals Environmental Controls of Oyster-PathogenicVibriospp. in Oregon Estuaries and a Shellfish Hatchery

2018 ◽  
Vol 84 (9) ◽  
Author(s):  
Mary R. Gradoville ◽  
Byron C. Crump ◽  
Claudia C. Häse ◽  
Angelicque E. White
Keyword(s):  
Coastal Waters ◽  
Multiple Stressors ◽  
Fold Increase ◽  
16S Rrna Gene Sequencing ◽  
Digital Pcr ◽  
Rrna Gene ◽  
Local Growth ◽  
Content Type ◽  
Environmental Controls ◽  
Planktonic State

ABSTRACTVibriospp. have been a persistent concern for coastal bivalve hatcheries, which are vulnerable to environmental pathogens in the seawater used for rearing larvae, yet the biogeochemical drivers of oyster-pathogenicVibriospp. in their planktonic state are poorly understood. Here, we present data tracking oyster-pathogenicVibriobacteria in Netarts Bay and Yaquina Bay in Oregon, USA, as well as in adjacent coastal waters and a local shellfish hatchery, through the 2015 upwelling season.Vibriopopulations were quantified using a culture-independent approach of high-throughputVibrio-specific 16S rRNA gene sequencing paired with droplet digital PCR, and abundances were analyzed in the context of local biogeochemistry. The most abundant putative pathogen in our samples wasVibrio coralliilyticus. Environmental concentrations of totalVibriospp. andV. coralliilyticuswere highest in Netarts Bay sediment samples and higher in seawater from Netarts Bay than from nearshore coastal waters or Yaquina Bay. In Netarts Bay, the highestV. coralliilyticusconcentrations were observed during low tide, and abundances increased throughout the summer. We hypothesize that the warm shallow waters in estuarine mudflats facilitate the local growth of theV. coralliilyticuspathogen. Samples from larval oyster tanks in Whiskey Creek Shellfish Hatchery, which uses seawater pumped directly from Netarts Bay, contained significantly lower totalVibriospecies concentrations, but roughly similarV. coralliilyticusconcentrations, than did the bay water, resulting in a 30-fold increase in the relative abundance of theV. coralliilyticuspathogen in hatchery tanks. This suggests that theV. coralliilyticuspathogen is able to grow or persist under hatchery conditions.IMPORTANCEIt has been argued that oyster-pathogenicVibriospp. have contributed to recent mortality events in U.S. shellfish hatcheries (R. A. Elston, H. Hasegawa, K. L. Humphrey, I. K. Polyak, and C. Häse, Dis Aquat Organ 82:119–134, 2008,https://doi.org/10.3354/dao01982); however, these events are often sporadic and unpredictable. The success of hatcheries is critically linked to the chemical and biological composition of inflowing seawater resources; thus, it is pertinent to understand the biogeochemical drivers of oyster-pathogenicVibriospp. in their planktonic state. Here, we show that Netarts Bay, the location of a local hatchery, is enriched in oyster-pathogenicV. coralliilyticuscompared to coastal seawater, and we hypothesize that conditions in tidal flats promote the local growth of this pathogen. Furthermore,V. coralliilyticusappears to persist in seawater pumped into the local hatchery. These results improve our understanding of the ecology and environmental controls of theV. coralliilyticuspathogen and could be used to improve future aquaculture efforts, as multiple stressors impact hatchery success.

scholarly journals Lachnospiraceae and Bacteroidales Alternative Fecal Indicators Reveal Chronic Human Sewage Contamination in an Urban Harbor

2011 ◽  
Vol 77 (19) ◽  
pp. 6972-6981 ◽  
Author(s):  
Ryan J. Newton ◽  
Jessica L. VandeWalle ◽  
Mark A. Borchardt ◽  
Marc H. Gorelick ◽  
Sandra L. McLellan
Keyword(s):  
Sequence Analysis ◽  
Genetic Marker ◽  
Microbial Community Composition ◽  
Fold Increase ◽  
Fecal Pollution ◽  
Plate Count ◽  
Rrna Gene ◽  
Fecal Indicators ◽  
Fecal Indicator ◽  
Content Type

ABSTRACTThe complexity of fecal microbial communities and overlap among human and other animal sources have made it difficult to identify source-specific fecal indicator bacteria. However, the advent of next-generation sequencing technologies now provides increased sequencing power to resolve microbial community composition within and among environments. These data can be mined for information on source-specific phylotypes and/or assemblages of phylotypes (i.e., microbial signatures). We report the development of a new genetic marker for human fecal contamination identified through microbial pyrotag sequence analysis of the V6 region of the 16S rRNA gene. Sequence analysis of 37 sewage samples and comparison with database sequences revealed a human-associated phylotype within theLachnospiraceaefamily, which was closely related to the genusBlautia. This phylotype, termed Lachno2, was on average the second most abundant fecal bacterial phylotype in sewage influent samples from Milwaukee, WI. We developed a quantitative PCR (qPCR) assay for Lachno2 and used it along with the qPCR-based assays for humanBacteroidales(based on the HF183 genetic marker), totalBacteroidalesspp., and enterococci and the conventionalEscherichia coliand enterococci plate count assays to examine the prevalence of fecal and human fecal pollution in Milwaukee's harbor. Both the conventional fecal indicators and the human-associated indicators revealed chronic fecal pollution in the harbor, with significant increases following heavy rain events and combined sewer overflows. The two human-associated genetic marker abundances were tightly correlated in the harbor, a strong indication they target the same source (i.e., human sewage). Human adenoviruses were routinely detected under all conditions in the harbor, and the probability of their occurrence increased by 154% for every 10-fold increase in the human indicator concentration. Both Lachno2 and humanBacteroidalesincreased specificity to detect sewage compared to general indicators, and the relationship to a human pathogen group suggests that the use of these alternative indicators will improve assessments for human health risks in urban waters.

scholarly journals Abrupt Temporal Fluctuations in the Chicken Fecal Microbiota Are Explained by Its Gastrointestinal Origin

2012 ◽  
Vol 78 (8) ◽  
pp. 2941-2948 ◽  
Author(s):  
M. Sekelja ◽  
I. Rud ◽  
S. H. Knutsen ◽  
V. Denstadli ◽  
B. Westereng ◽  
...  
Keyword(s):  
Barrier Function ◽  
16S Rrna Gene Sequencing ◽  
Fecal Microbiota ◽  
Pathogen Transmission ◽  
Rrna Gene ◽  
Multivariate Statistical ◽  
Content Type ◽  
Factors Affecting ◽  
Temporal Fluctuations ◽  
Gastric Barrier

ABSTRACTOne of the main challenges in understanding the composition of fecal microbiota is that it can consist of microbial mixtures originating from different gastrointestinal (GI) segments. Here, we addressed this challenge for broiler chicken feces using a direct 16S rRNA gene-sequencing approach combined with multivariate statistical analyses. Broiler feces were chosen because of easy sampling and the importance for pathogen transmission to the human food chain. Feces were sampled daily for 16 days from chickens with and without a feed structure-induced stimulation of the gastric barrier function. Overall, we found four dominant microbial phylogroups in the feces. Two of the phylogroups were related to clostridia, one to lactobacilli, and one toEscherichia/Shigella. The relative composition of these phylogroups showed apparent stochastic temporal fluctuations in feces. Analyses of dissected chickens at the end of the experiment, however, showed that the two clostridial phylogroups were correlated to the microbiota in the cecum/colon and the small intestine, while the upper gut (crop and gizzard) microbiota was correlated to the lactobacillus phylogroup. In addition, chickens with a stimulated gizzard also showed less of the proximate GI dominating bacterial group in the feces, supporting the importance of the gastric barrier function. In conclusion, our results suggest that GI origin is a main determinant for the chicken fecal microbiota composition. This knowledge will be important for future understanding of factors affecting shedding of both harmful and beneficial gastrointestinal bacteria through feces.

scholarly journals Citroniella saccharovorans gen. nov. sp. nov., a member of the family Peptoniphilaceae isolated from a human fecal sample from a coastal traditional community member

2019 ◽  
Vol 69 (4) ◽  
pp. 1142-1148 ◽  
Author(s):  
Nisha B. Patel ◽  
Alexandra J. Obregón-Tito ◽  
Raul Y. Tito ◽  
Omar Trujillo-Villaroel ◽  
Luis Marin-Reyes ◽  
...  
Keyword(s):  
Fecal Sample ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
The Novel ◽  
Content Type ◽  
Link Type ◽  
Novel Bacterium ◽  
The Family ◽  
Diamino Acid ◽  
Rrna Gene Sequencing

A novel Gram-stain-positive, non-motile, non-spore-forming coccus-shaped obligately anaerobic bacterium was recovered from a fecal sample obtained from an individual from a traditional community located on the southern coast of Peru. The results of analysis based on 16S rRNA gene sequencing indicated the novel bacterium to be phylogenetically distinct from other genera of members of the Peptoniphilaceae family, sharing a loose affinity with the genera Ezakiella , Finegoldia , Gallicola and Parvimonas . The major cellular fatty acids of the novel isolate were determined to be C16:0, C17:1ω8c, and C18:1ω9c. The DNA G+C content was 29.9 mol%. End products of metabolism from peptone yeast glucose broth (PYG) were determined to be acetate and methyl succinate. The diagnostic diamino acid present in the cell wall was lysine. On the basis of the phenotypic, chemotaxonomic and phylogenetic results the organism is a member of a novel genus belonging to the family Peptoniphilaceae for which the name Citroniella saccharovorans gen nov. sp. nov., is proposed. The type strain is M6.X9T (DSM 29873T=CCUG 66799T).

scholarly journals Tsukamurella pulmonis conjunctivitis in patients with an underlying nasolacrimal duct obstruction – report of two cases

2020 ◽  
Author(s):  
Peter Kechker ◽  
Yigal Senderovich ◽  
Shifra Ken-Dror ◽  
Sivan Laviad-Shitrit ◽  
Malka Halpern
Keyword(s):  
Type Species ◽  
Previous History ◽  
16S Rrna Gene Sequencing ◽  
Nasolacrimal Duct ◽  
Nasolacrimal Duct Obstruction ◽  
Rrna Gene ◽  
Eye Drops ◽  
Content Type ◽  
Duct Obstruction ◽  
Link Type

Tsukamurella pulmonis ( Actinobacteria ), a Gram-positive, obligate aerobic and weakly or variably acid-fast bacterium, is an opportunistic pathogen. Here we report two cases of conjunctivitis caused by T. pulmonis . Both patients had a previous history of nasolacrimal duct obstruction (NLDO). Isolation of T. pulmonis was performed on chocolate, tryptic soy blood and Columbia nalidixic agars. After 24 h of incubation, odourless, white-greyish, membrane-like colonies were observed. The VITEK-2 bacterial identifier system failed to identify the species, while Vitek-MS matrix-assisted laser desorption ionization time-of-flight technology, successfully identified the isolate from case 2 but not from case 1. Final identification was verified using 16S rRNA gene sequencing. An antibiogram was performed and according to the results cefazoline in addition to vancomycin eye drops for 5 days, were suggested as a treatment in case 1. In case 2 the infection was ended without treatment. This is the first report of Tsukamurella as a pathogen that causes conjunctivitis in patients with NLDO.

scholarly journals Impact of Oral Fidaxomicin Administration on the Intestinal Microbiota and Susceptibility to Clostridium difficile Colonization in Mice

2018 ◽  
Vol 62 (5) ◽  
Author(s):  
N. J. Ajami ◽  
J. L. Cope ◽  
M. C. Wong ◽  
J. F. Petrosino ◽  
L. Chesnel
Keyword(s):  
Clostridium Difficile ◽  
Gut Microbiota ◽  
16S Rrna Gene Sequencing ◽  
Taxonomic Structure ◽  
Rrna Gene ◽  
Colonization Resistance ◽  
Content Type ◽  
Rrna Gene Sequencing ◽  
Hospital Acquired ◽  
Predetermined Time

ABSTRACT Clostridium difficile infection (CDI), a common cause of hospital-acquired infections, typically occurs after disruption of the normal gut microbiome by broad-spectrum antibiotics. Fidaxomicin is a narrow-spectrum antibiotic that demonstrates a reduced impact on the normal gut microbiota and is approved for the treatment of CDI. To further explore the benefits of this property, we used a murine model to examine the effects of fidaxomicin versus vancomycin on gut microbiota and susceptibility to C. difficile colonization while tracking microbiota recovery over time. Mice were exposed to fidaxomicin or vancomycin by oral gavage for 3 days and subsequently challenged with C. difficile spores at predetermined time points up to 21 days postexposure to antibiotics. Fecal samples were subsequently collected for analysis. Twenty-four hours postchallenge, mice were euthanized and the colon contents harvested. The microbiota was characterized using 16S rRNA gene sequencing. All fidaxomicin-exposed mice (except for one at day 8) were resistant to C. difficile colonization. However, 9 of 15 vancomycin-exposed mice were susceptible to C. difficile colonization until day 12. All vancomycin-exposed mice recovered colonization resistance by day 16. Bacterial diversity was similar prior to antibiotic exposure in both arms and decreased substantially after exposure. A shift in taxonomic structure and composition occurred after both exposures; however, the shift was greater in vancomycin-exposed than in fidaxomicin-exposed mice. In summary, compared with vancomycin, fidaxomicin exposure had less impact on microbiota composition, promoted faster microbial recovery, and had less impact on the loss of C. difficile colonization resistance.

scholarly journals Transition of Bacterial Diversity and Composition in Tongue Microbiota during the First Two Years of Life

mSphere ◽  
2019 ◽  
Vol 4 (3) ◽  
Author(s):  
Shinya Kageyama ◽  
Mikari Asakawa ◽  
Toru Takeshita ◽  
Yukari Ihara ◽  
Shunsuke Kanno ◽  
...  
Keyword(s):  
Oral Cavity ◽  
Bacterial Diversity ◽  
Bacterial Species ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Oral Microbiota ◽  
Bacterial Composition ◽  
Content Type ◽  
Operational Taxonomic Units ◽  
Rrna Gene Sequencing

ABSTRACTNewborns are constantly exposed to various microbes from birth; hence, diverse commensal bacteria colonize the oral cavity. However, how or when these bacteria construct a complex and stable ecosystem remains unclear. This prospective cohort study examined the temporal changes in bacterial diversity and composition in tongue microbiota during infancy. We longitudinally collected a total of 464 tongue swab samples from 8 infants (age of <6 months at baseline) for approximately 2 years. We also collected samples from 32 children (aged 0 to 2 years) and 73 adults (aged 20 to 29 years) cross-sectionally as control groups. Bacterial diversities and compositions were determined by 16S rRNA gene sequencing. The tongue bacterial diversity in infancy, measured as the number of observed operational taxonomic units (OTUs), rapidly increased and nearly reached the same level as that in adults by around 80 weeks. The overall tongue bacterial composition in the transitional phase, 80 to 120 weeks, was more similar to that of adults than to that of the early exponential phase (EEP), 10 to 29 weeks, according to analysis of similarities. Dominant OTUs in the EEP corresponding toStreptococcus perorisandStreptococcus lactariusexponentially decreased immediately after EEP, around 30 to 49 weeks, whereas several OTUs corresponding toGranulicatella adiacens,Actinomyces odontolyticus, andFusobacterium periodonticumreciprocally increased during the same period. These results suggest that a drastic compositional shift of tongue microbiota occurs before the age of 1 year, and then bacterial diversity and overall bacterial composition reach levels comparable to those in adults by the age of 2 years.IMPORTANCEEvaluating the development of oral microbiota during infancy is important for understanding the subsequent colonization of bacterial species and the process of formation of mature microbiota in the oral cavity. We examined tongue microbiota longitudinally collected from 8 infants and found that drastic compositional shifts in tongue microbiota occur before the age of 1 year, and then bacterial diversity and overall bacterial composition reach levels comparable to those in adults by the age of 2 years. These results may be helpful for preventing the development of various diseases associated with oral microbiota throughout life.

scholarly journals Whole-Genome Sequencing ofAggregatibacterSpecies Isolated from Human Clinical Specimens and Description ofAggregatibacter kilianiisp. nov.

2018 ◽  
Vol 56 (7) ◽  
Author(s):  
May Murra ◽  
Lisbeth Lützen ◽  
Aynur Barut ◽  
Reinhard Zbinden ◽  
Marianne Lund ◽  
...  
Keyword(s):  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Whole Genome ◽  
Content Type ◽  
Clinical Specimens ◽  
Phylogenetic Cluster ◽  
Invasive Infections ◽  
Rrna Gene Sequencing

ABSTRACTAggregatibacterspecies are commensal bacteria of human mucosal surfaces that are sometimes involved in serious invasive infections. During the investigation of strains cultured from various clinical specimens, we encountered a coherent group of 10 isolates that could not be allocated to any validly named species by phenotype, mass spectrometry, or partial 16S rRNA gene sequencing. Whole-genome sequencing revealed a phylogenetic cluster related to but separate fromAggregatibacter aphrophilus. The meanin silicoDNA hybridization value for strains of the new cluster versusA. aphrophiluswas 56% (range, 53.7 to 58.0%), whereas the average nucleotide identity was 94.4% (range, 93.9 to 94.8%). The new cluster exhibited aggregative properties typical of the genusAggregatibacter. Key phenotypic tests for discrimination of the new cluster from validly namedAggregatibacterspecies are alanine-phenylalanine-proline arylamidase,N-acetylglucosamine, and β-galactosidase. The nameAggregatibacter kilianiiis proposed, with PN_528 (CCUG 70536Tor DSM 105094T) as the type strain.

Thioalkalivibrio sulfidiphilus sp. nov., a haloalkaliphilic, sulfur-oxidizing gammaproteobacterium from alkaline habitats

2012 ◽  
Vol 62 (Pt_8) ◽  
pp. 1884-1889 ◽  
Author(s):  
Dimitry Y. Sorokin ◽  
Maria S. Muntyan ◽  
Anzhela N. Panteleeva ◽  
Gerard Muyzer
Keyword(s):  
Soda Lake ◽  
16S Rrna Gene Sequencing ◽  
Salinity Range ◽  
Rrna Gene ◽  
Type I ◽  
Ribulose Bisphosphate Carboxylase ◽  
Bisphosphate Carboxylase ◽  
Content Type ◽  
Link Type ◽  
Sulfur Oxidizing

A moderately salt-tolerant and obligately alkaliphilic, chemolithoautotrophic sulfur-oxidizing bacterium, strain HL-EbGr7T, was isolated from a full-scale bioreactor removing H2S from biogas under oxygen-limited conditions. Another strain, ALJ17, closely related to HL-EbGr7T, was isolated from a Kenyan soda lake. Cells of the isolates were relatively long, slender rods, motile by a polar flagellum. Although both strains were obligately aerobic, micro-oxic conditions were preferred, especially at the beginning of growth. Chemolithoautotrophic growth was observed with sulfide and thiosulfate in a pH range of 8.0–10.5 (optimum at pH 10.0) and a salinity range of 0.2–1.5 M total Na+ (optimum at 0.4 M). The genome sequence of strain HL-EbGr7T demonstrated the presence of genes encoding the reverse Dsr pathway and a truncated Sox pathway for sulfur oxidation and enzymes of the Calvin–Benson cycle of autotrophic CO2 assimilation with ribulose-bisphosphate carboxylase/oxygenase (RuBisCO) type I. The dominant cellular fatty acids were C18 : 1ω7, C16 : 0 and C19 : 0 cyclo. Based on 16S rRNA gene sequencing, the two strains belonged to a single phylotype within the genus Thioalkalivibrio in the Gammaproteobacteria . Despite being related most closely to Thioalkalivibrio denitrificans , the isolates were unable to grow by denitrification. On the basis of phenotypic and phylogenetic analysis, the novel isolates are proposed to represent a novel species, Thioalkalivibrio sulfidiphilus sp. nov., with the type strain HL-EbGr7T ( = NCCB 100376T  = UNIQEM U246T).

scholarly journals Microbe-Metabolite Associations Linked to the Rebounding Murine Gut Microbiome Postcolonization with Vancomycin-Resistant Enterococcus faecium

mSystems ◽  
2020 ◽  
Vol 5 (4) ◽  
Author(s):  
Andre Mu ◽  
Glen P. Carter ◽  
Lucy Li ◽  
Nicole S. Isles ◽  
Alison F. Vrbanac ◽  
...  
Keyword(s):  
Gut Microbiome ◽  
Enterococcus Faecium ◽  
Molecular Mechanisms ◽  
Microbial Community Composition ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Content Type ◽  
Functional Roles ◽  
Specific Pathogen ◽  
Vancomycin Resistant

ABSTRACT Vancomycin-resistant Enterococcus faecium (VREfm) is an emerging antibiotic-resistant pathogen. Strain-level investigations are beginning to reveal the molecular mechanisms used by VREfm to colonize regions of the human bowel. However, the role of commensal bacteria during VREfm colonization, in particular following antibiotic treatment, remains largely unknown. We employed amplicon 16S rRNA gene sequencing and metabolomics in a murine model system to try and investigate functional roles of the gut microbiome during VREfm colonization. First-order taxonomic shifts between Bacteroidetes and Tenericutes within the gut microbial community composition were detected both in response to pretreatment using ceftriaxone and to subsequent VREfm challenge. Using neural networking approaches to find cooccurrence profiles of bacteria and metabolites, we detected key metabolome features associated with butyric acid during and after VREfm colonization. These metabolite features were associated with Bacteroides, indicative of a transition toward a preantibiotic naive microbiome. This study shows the impacts of antibiotics on the gut ecosystem and the progression of the microbiome in response to colonization with VREfm. Our results offer insights toward identifying potential nonantibiotic alternatives to eliminate VREfm through metabolic reengineering to preferentially select for Bacteroides. IMPORTANCE This study demonstrates the importance and power of linking bacterial composition profiling with metabolomics to find the interactions between commensal gut bacteria and a specific pathogen. Knowledge from this research will inform gut microbiome engineering strategies, with the aim of translating observations from animal models to human-relevant therapeutic applications.

Streptococcus orisasini sp. nov. and Streptococcus dentasini sp. nov., isolated from the oral cavity of donkeys

2013 ◽  
Vol 63 (Pt_8) ◽  
pp. 2782-2786 ◽  
Author(s):  
Kazuko Takada ◽  
Masanori Saito ◽  
Osamu Tsudukibashi ◽  
Takachika Hiroi ◽  
Masatomo Hirasawa
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Strain ◽  
Type Species ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Biochemical Tests ◽  
Content Type ◽  
Link Type ◽  
Sequencing Studies

Four Gram-positive, catalase-negative, coccoid isolates that were obtained from donkey oral cavities formed two distinct clonal groups when characterized by phenotypic and phylogenetic studies. From the results of biochemical tests, the organisms were tentatively identified as a streptococcal species. Comparative 16S rRNA gene sequencing studies confirmed the organisms to be members of the genus Streptococcus . Two of the isolates were related most closely to Streptococcus ursoris with 95.6 % similarity based on the 16S rRNA gene and to Streptococcus ratti with 92.0 % similarity based on the 60 kDa heat-shock protein gene (groEL). The other two isolates, however, were related to Streptococcus criceti with 95.0 and 89.0 % similarities based on the 16S rRNA and groEL genes, respectively. From both phylogenetic and phenotypic evidence, the four isolates formed two distinct clonal groups and are suggested to represent novel species of the genus Streptococcus . The names proposed for these organisms are Streptococcus orisasini sp. nov. (type strain NUM 1801T = JCM 17942T = DSM 25193T) and Streptococcus dentasini sp. nov. (type strain NUM 1808T = JCM 17943T = DSM 25137T).

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