scholarly journals Priority effects among amphibian microbes lead to varying levels of Bd infection

2021 ◽  
Author(s):  
Elle M Barnes ◽  
JD Lewis
Keyword(s):  
Bacterial Communities ◽  
Batrachochytrium Dendrobatidis ◽  
Pathogenic Fungus ◽  
Bacterial Species ◽  
Priority Effects ◽  
Bacterial Composition ◽  
Composition And Structure ◽  
Risk Of Extinction ◽  
Inhibitory Potential

Priority effects in host-associated microbiomes can influence not only community composition and structure, but also community functions, such as disease resistance. However, evidence for these priority effects remains scarce. Past studies suggest that amphibian protection from chytridiomycosis, caused by the pathogenic fungus Batrachochytrium dendrobatidis (Bd), is related to antifungal bacterial composition on host skin. Priority effects in these bacterial communities may influence susceptibility to Bd, but this possibility has not been tested. Using in vitro microcosms, we demonstrated that priority effects can influence interactions among amphibian-associated microbes. We observed strong priority effects irrespective of high antifungal ability such that the Bd-inhibitory potential of two strongly inhibitory bacterial species did not always produce higher levels of Bd-inhibition. This result suggests that interactions may be more complex than previously thought. Additionally, our results suggest that priority effects between commensal and pathogenic taxa can be either facilitatory or inhibitory, with the strength and direction of this effect dependent on the composition of the community. Thus, changes in assembly may lead to varying levels of Bd infection, influencing how we might augment amphibian-associated microbiomes to conserve taxa currently at risk of extinction.

scholarly journals Tagging Frogs with Passive Integrated Transponders Causes Disruption of the Cutaneous Bacterial Community and Proliferation of Opportunistic Fungi

2014 ◽  
Vol 80 (15) ◽  
pp. 4779-4784 ◽  
Author(s):  
Rachael E. Antwis ◽  
Gerardo Garcia ◽  
Andrea L. Fidgett ◽  
Richard F. Preziosi
Keyword(s):  
Bacterial Community ◽  
Microbial Communities ◽  
Bacterial Communities ◽  
Pathogenic Fungus ◽  
Fold Increase ◽  
Bacterial Strains ◽  
Opportunistic Fungi ◽  
Content Type ◽  
Pit Tagging

ABSTRACTSymbiotic bacterial communities play a key role in protecting amphibians from infectious diseases including chytridiomycosis, caused by the pathogenic fungusBatrachochytrium dendrobatidis. Events that lead to the disruption of the bacterial community may have implications for the susceptibility of amphibians to such diseases. Amphibians are often marked both in the wild and in captivity for a variety of reasons, and although existing literature indicates that marking techniques have few negative effects, the response of cutaneous microbial communities has not yet been investigated. Here we determine the effects of passive integrated transponder (PIT) tagging on culturable cutaneous microbial communities of captive Morelet's tree frogs (Agalychnis moreletii) and assess the isolated bacterial strains for anti-B. dendrobatidisactivityin vitro. We find that PIT tagging causes a major disruption to the bacterial community associated with the skin of frogs (∼12-fold increase in abundance), as well as a concurrent proliferation in resident fungi (up to ∼200-fold increase). Handling also caused a disruption the bacterial community, although to a lesser extent than PIT tagging. However, the effects of both tagging and handling were temporary, and after 2 weeks, the bacterial communities were similar to their original compositions. We also identify two bacterial strains that inhibitB. dendrobatidis, one of which increased in abundance on PIT-tagged frogs at 1 day postmarking, while the other was unaffected. These results show that PIT tagging has previously unobserved consequences for cutaneous microbial communities of frogs and may be particularly relevant for studies that intend to use PIT tagging to identify individuals involved in trials to develop probiotic treatments.

Biocomplexity in the oral cavity – the basics of structure in supragingival bacterial communities

Biofilms ◽  
2004 ◽  
Vol 1 (4) ◽  
pp. 329-335 ◽  
Author(s):  
R. J. Palmer ◽  
P. I. Diaz ◽  
P. E. Kolenbrander
Keyword(s):  
Oral Cavity ◽  
Bacterial Communities ◽  
Bacterial Species ◽  
Lessons Learned ◽  
Ex Situ ◽  
Scientific Approach ◽  
16 S Rrna ◽  
Microbiological Data

The human oral microbial ecosystem is one of the best characterized and highly complex bacterial communities known. It is estimated that about 600 bacterial species exist in the mouth and that 85% of those are currently known at the molecular (16 S rRNA) level. The major bacterial physiologies occurring in the oral cavity have been known for many years, and knowledge exists of the distribution of organisms in time (as plaque accumulates) and in space (different environments within the mouth). However, only rudimentary data are available on interactions between the bacterial species. It is precisely these interactions that, along with the interactions of the developing community with its human host, must drive the succession of genera that is observed to occur. In the reductionist scientific approach to studying such interactions, disrupted plaque is used to isolate single organisms, and interactions between these organisms are examined by recombining the organisms ex situ. Lessons learned from these in vitro studies can be applied to understand empirical observations made in vivo. However, this approach begins with the primary assumption that the chosen interaction does in fact occur in vivo. The accessibility and the well-characterized nature of the oral ecosystem presents an opportunity for approaching the problem from the opposite direction; one can capture a community very early in development in vivo, then apply in vitro methods to sort out the interactions within that community. This latter approach begins with a set of organisms known to interact in vivo. A combination of both approaches should yield robust microbiological data suitable for in silico modeling and analyses.

scholarly journals An Assessment of the Microbial Diversity Present on the Surface of Naturally Incubated House Wren Eggs

2013 ◽  
Vol 6 (1) ◽  
pp. 32-39 ◽  
Author(s):  
Beth A. Potter ◽  
Brian M. Carlson ◽  
Andrea E. Adams ◽  
Margaret A. Voss ◽  
J.-L. Vasseur
Keyword(s):  
Microbial Community ◽  
Bacterial Communities ◽  
Bacterial Species ◽  
Fungal Growth ◽  
Temperature Fluctuations ◽  
House Wren ◽  
Bacterial Composition ◽  
Incubation Behavior ◽  
Three Stages

During ovipositioning, avian eggshells become susceptible to bacterial and fungal growth and studies have shown that a community of these microorganisms, or microflora, is maintained on eggshells throughout the incubation process. To determine the possible role of these microorganisms on embryonic development, it is first important to understand the composition of the microbial community present on the surface of the egg. A limited amount of studies have been published in this area; thus, the objective of this study was to broaden this area of study and determine what bacterial communities are found on the surface of naturally-incubated House Wren eggs across three stages of incubation (pre, early, and late) as defined by egg temperature. Our data uniquely suggest that the eggshell microflora is dynamic and that this may be regulated by temperature fluctuations due to intermittent incubation behavior. Using culture-based techniques, 46 different bacterial species were identified belonging to 13 bacterial families and 20 genera. The majority of bacteria belonged to the Pseudomonas, Staphylococcus, Stenotrophomonas, or Burkholderia genera and have been previously associated with avian eggs and nests. Bacteria within the Pseudomonas genus were the most predominant and we hypothesize that their maintenance may be linked to their ability to produce antibiotic substances called bacteriocins. The bacterial composition of the microflora isolated in this study also suggests that avian egg microfloras are derived from environmental origins.

Duration of continuous cropping with straw return affects the composition and structure of soil bacterial communities in cotton fields

2018 ◽  
Vol 64 (3) ◽  
pp. 167-181 ◽  
Author(s):  
Lei Yang ◽  
Lanlan Tan ◽  
Fenghua Zhang ◽  
William Jeffrey Gale ◽  
Zhibo Cheng ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Bacterial Species ◽  
Illumina Miseq ◽  
Continuous Cropping ◽  
Cotton Production ◽  
Positive Effects ◽  
Soil Bacterial Communities ◽  
Composition And Structure ◽  
Straw Return ◽  
Soil Bacterial

Salinized land in the China’s Xinjiang Region is being reclaimed for continuous cotton production. The specific objectives of this field study were (i) to compare bacterial composition and diversity in unfarmed (i.e., unreclaimed) and continuously (5, 10, 15, and 20 years) cropped soils and (ii) to explore correlations between soil properties and the bacterial communities identified by Illumina MiSeq sequencing. The results showed that bacterial species richness and diversity increased for 10–15 years and then declined when salinized land was reclaimed for cotton production. Proteobacteria and Firmicutes were the dominant phyla in unfarmed soil. Continuous cropping reduced the abundance of Firmicutes but increased that of Chloroflexi, Acidobacteria, and Actinobacteria. Cluster analyses showed that the greatest similarities in bacterial communities were between the 5- and 10-year treatments and between the 15- and 20-year treatments. Soil pH, electrical conductivity, alkali-hydrolyzable N, and available P were significantly correlated with bacterial community distribution. Overall, cotton production improved soil physicochemical properties and altered the structure and composition of soil bacterial communities compared with unfarmed soil. These positive effects began to decrease after 10–15 years of continuous cotton production.

scholarly journals Distinct Habitats Select Particular Bacterial Communities in Mangrove Sediments

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Lidianne L. Rocha ◽  
Geórgia B. Colares ◽  
Vanessa L. R. Nogueira ◽  
Fernanda A. Paes ◽  
Vânia M. M. Melo
Keyword(s):  
Bacterial Communities ◽  
Environmental Variables ◽  
Rflp Analysis ◽  
Mangrove Ecosystem ◽  
Bacterial Composition ◽  
Bacterial Populations ◽  
Oil Exploitation ◽  
Composition And Structure ◽  
The Relationship ◽  
High Diversity

We investigated the relationship among environmental variables, composition, and structure of bacterial communities in different habitats in a mangrove located nearby to an oil exploitation area, aiming to retrieve the natural pattern of bacterial communities in this ecosystem. The T-RFLP analysis showed a high diversity of bacterial populations and an increase in the bacterial richness from habitats closer to the sea and without vegetation (S1) to habitats covered byAvicennia schaueriana(S2) andRhizophora mangle(S3). Environmental variables in S1 and S2 were more similar than in S3; however, when comparing the bacterial compositions, S2 and S3 shared more OTUs between them, suggesting that the presence of vegetation is an important factor in shaping these bacterial communities.In silicoanalyses of the fragments revealed a high diversity of the class Gammaproteobacteria in the 3 sites, although in general they presented quite different bacterial composition, which is probably shaped by the specificities of each habitat. This study shows that microhabitats inside of a mangrove ecosystem harbor diverse and distinct microbiota, reinforcing the need to conserve these ecosystems as a whole.

scholarly journals Human Milk Oligosaccharides Promote the Growth of Staphylococci

2012 ◽  
Vol 78 (14) ◽  
pp. 4763-4770 ◽  
Author(s):  
K. M. Hunt ◽  
J. Preuss ◽  
C. Nissan ◽  
C. A. Davlin ◽  
J. E. Williams ◽  
...  
Keyword(s):  
Human Milk ◽  
Bacterial Communities ◽  
Bacterial Species ◽  
Human Milk Oligosaccharides ◽  
Milk Oligosaccharides ◽  
Content Type ◽  
Nutritional Conditions ◽  
Culture Independent ◽  
Lactating Mammary Gland

ABSTRACTHuman milk oligosaccharides (HMO), which constitute a major component of human milk, promote the growth of particular bacterial species in the infant's gastrointestinal tract. We hypothesized that HMO also interact with the bacterial communities present in human milk. To test this hypothesis, two experiments were conducted. First, milk samples were collected from healthy women (n= 16); culture-independent analysis of the bacterial communities was performed, HMO content was analyzed, and the relation between these factors was investigated. A positive correlation was observed between the relative abundance ofStaphylococcusand total HMO content (r= 0.66). In a follow-up study, we conducted a series ofin vitrogrowth curve experiments utilizingStaphylococcus aureusorStaphylococcus epidermidisand HMO isolated from human milk. HMO exhibited stimulatory effects on bacterial growth under various nutritional conditions. Analysis of culture supernatants from these experiments revealed that HMO did not measurably disappear from the culture medium, indicating that the growth-enhancing effects were not a result of bacterial metabolism of the HMO. Instead, stimulation of growth caused greater utilization of amino acids in minimal medium. Collectively, the data provide evidence that HMO may promote the growth ofStaphylococcusspecies in the lactating mammary gland.

scholarly journals Halophytic bacterial endophytome: a potential source of beneficial microbes for a sustainable agriculture

2020 ◽  
Author(s):  
Christos A. Christakis ◽  
Georgia Daskalogiannis ◽  
Anastasia Chatzakis ◽  
Emmanouil A. Markakis ◽  
Angeliki Sagia ◽  
...  
Keyword(s):  
Sustainable Agriculture ◽  
Endophytic Bacteria ◽  
Pathogenic Fungus ◽  
Bacterial Species ◽  
Species Abundance ◽  
Global Strategy ◽  
In Planta ◽  
Promoting Effect ◽  
Cakile Maritima

AbstractHalophytes have evolved several strategies to survive in saline environments; however, additional support from their associated microbiota could help combat adverse conditions. Endophytic communities of halophytes may be different than those in other plants because salinity acts as an environmental filter. At the same time, they may contribute to the host’s adaptation to adverse environmental conditions and can improve host tolerance against various biotic and abiotic stresses, which may be of importance in modern and sustainable agriculture.In this study the culturable endophytic bacteria of three halophytic species Cakile maritima, Matthiola tricuspidata and Crithmum maritimum were isolated and identified. Endophytic bacteria were isolated from roots and leaves of the sampled plants. Significant differences were observed in bacterial species abundance among different plant species and tissue from which the isolates were obtained. In total, 115 strains were identified by analysis of complete 16S rDNA sequences, while the majority of these isolates were derived from the root samples.The strains were evaluated for their ability to: 1) grow in-vitro in high levels of NaCl; 2) inhibit the growth of the economically important plant pathogenic fungus Verticillium dahliae in vitro and in planta, the human pathogenic fungus Aspergillus fumigatus in vitro, as well as, the economically important plant bacterial pathogens Ralstonia solanacearum and Clavibacter michiganensis in vitro; 3) provide salt tolerance in planta; 4) provide growth promoting effect in planta.Additionally, the genomes of twelve selected isolates, exhibiting interesting features, were sequenced and analysed. Three novel bacterial species were identified that belong to the genus Pseudomonas (two strains) and Arthrobacter (one strain).The outcome of our study is the proof-of-concept that the crop wild relatives (CWR) halophytic microbiome could potentially serve as a source of beneficial microorganisms that could be used (as unique species or as artificial communities) as Bio-Inoculants, for the enhancement of plant growth and stress tolerance in crops, including the high-salinity stress.This is very important in the era of ecosystem degradation and climate change, where the maximizing microbial functions in agroecosystems could be a prerequisite for the future of global sustainable agriculture. Globally, there is a strong need for the identification and bio-banking of novel beneficial endophytic microbes with as many desirable characters, for the development of a new environmentally friendly global strategy in food production that will be based in the sustainable agriculture with low chemical inputs and a low environmental impact.

Effects of Tham Nasal Alkalinization on Airway Microbial Communities: A Pilot Study in Non-CF and CF Adults

2021 ◽  
pp. 000348942110518
Author(s):  
Zachary M. Holliday ◽  
Janice L. Launspach ◽  
Lakshmi Durairaj ◽  
Pradeep K. Singh ◽  
Joseph Zabner ◽  
...  
Keyword(s):  
Pilot Study ◽  
Bacterial Communities ◽  
Nasal Swab ◽  
Bacterial Species ◽  
Nasal Airway ◽  
Clinical Trial Registration ◽  
Bacterial Composition ◽  
Nasal Swabs ◽  
Surface Liquid ◽  
Corynebacterium Pseudodiphtheriticum

Objectives: In cystic fibrosis (CF), loss of CFTR-mediated bicarbonate secretion reduces the airway surface liquid (ASL) pH causing airway host defense defects. Aerosolized sodium bicarbonate can reverse these defects, but its effects are short-lived. Aerosolized tromethamine (THAM) also raises the ASL pH but its effects are much longer lasting. In this pilot study, we tested the hypothesis that nasally administered THAM would alter the nasal bacterial composition in adults with and without CF. Methods: Subjects (n = 32 total) received intranasally administered normal saline or THAM followed by a wash out period prior to receiving the other treatment. Nasal bacterial cultures were obtained prior to and after each treatment period. Results: At baseline, nasal swab bacterial counts were similar between non-CF and CF subjects, but CF subjects had reduced microbial diversity. Both nasal saline and THAM were well-tolerated. In non-CF subjects, nasal airway alkalinization decreased both the total bacterial density and the gram-positive bacterial species recovered. In both non-CF and CF subjects, THAM decreased the amount of Corynebacterium accolens detected, but increased the amount of Corynebacterium pseudodiphtheriticum recovered on nasal swabs. A reduction in Staphylococcus aureus nasal colonization was also found in subjects who grew C. pseudodiphtheriticum. Conclusions: This study shows that aerosolized THAM is safe and well-tolerated and that nasal airway alkalinization alters the composition of mucosal bacterial communities. Clinical Trial Registration: NCT00928135 ( https://clinicaltrials.gov/ct2/show/NCT00928135 ).

scholarly journals Inter-site and interpersonal diversity of salivary and tongue microbiomes, and the effect of oral care tablets

F1000Research ◽  
2020 ◽  
Vol 9 ◽  
pp. 1477
Author(s):  
Hugo Maruyama ◽  
Ayako Masago ◽  
Takayuki Nambu ◽  
Chiho Mashimo ◽  
Kazuya Takahashi ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Oral Care ◽  
Alpha Diversity ◽  
Oral Microbiome ◽  
Oral Microbiota ◽  
Tongue Coating ◽  
Bacterial Composition ◽  
Operational Taxonomic Units ◽  
Health And Disease

Background: Oral microbiota has been linked to both health and disease. Specifically, tongue-coating microbiota has been implicated in aspiration pneumonia and halitosis. Approaches altering one's oral microbiota have the potential to improve oral health and prevent diseases. Methods: Here, we designed a study that allows simultaneous monitoring of the salivary and tongue microbiomes during an intervention on the oral microbiota. We applied this study design to evaluate the effect of single-day use of oral care tablets on the oral microbiome of 10 healthy individuals. Tablets with or without actinidin, a protease that reduces biofilm formation in vitro, were tested. Results: Alpha diversity in the saliva was higher than that on the tongue without the intervention. The core operational taxonomic units (OTUs) common to both sites were identified. The salivary and tongue microbiomes of one individual tended to be more similar to one another than to those of other individuals. The tablets did not affect the alpha or beta diversity of the oral microbiome, nor the abundance of specific bacterial species. Conclusions: While the salivary and tongue microbiomes differ significantly in terms of bacterial composition, they show inter- rather than intra-individual diversity. A one-day usage of oral care tablets did not alter the salivary or tongue microbiomes of healthy adults. Whether the use of oral tablets for a longer period on healthy people or people with greater tongue coating accumulation shifts their oral microbiome needs to be investigated.

scholarly journals Effects of THAM Nasal Alkalinization on Airway Microbial Communities: A Pilot Study

2021 ◽  
Author(s):  
Zachary M. Holliday ◽  
Janice L. Launspach ◽  
Lakshmi Durairaj ◽  
Pradeep K. Singh ◽  
Joseph Zabner ◽  
...  
Keyword(s):  
Pilot Study ◽  
Bacterial Communities ◽  
Nasal Swab ◽  
Bacterial Species ◽  
Airway Surface Liquid ◽  
Nasal Airway ◽  
Bacterial Composition ◽  
Bacterial Cultures ◽  
Nasal Swabs ◽  
Surface Liquid

ABSTRACTObjectivesIn cystic fibrosis (CF), loss of CFTR-mediated bicarbonate secretion reduces the airway surface liquid (ASL) pH causing airway host defense defects. Aerosolized sodium bicarbonate can reverse these defects, but its effects are short-lived. Aerosolized tromethamine (THAM) also raises the ASL pH but its effects are much longer lasting. In this pilot study, we tested the hypothesis that nasally administered THAM would alter the nasal bacterial composition in adults with and without CF.MethodsSubjects (n=32 total) received intranasally administered normal saline or THAM followed by a wash out period prior to receiving the other treatment. Nasal bacterial cultures were obtained prior to and after each treatment period.ResultsAt baseline, nasal swab bacterial counts were similar between non-CF and CF subjects, but CF subjects had reduced microbial diversity. Both nasal saline and THAM were well-tolerated. In non-CF subjects, nasal airway alkalinization decreased both the total bacterial density and the gram-positive bacterial species recovered. In both non-CF and CF subjects, THAM decreased the amount of C. accolens detected, but increased the amount of C. pseudodiphtheriticum recovered on nasal swabs. A reduction in S. aureus nasal colonization was also found in subjects who grew C. pseudodiphtheriticum.ConclusionsThis study shows that aerosolized THAM is safe and well-tolerated and that nasal airway alkalinization alters the composition of mucosal bacterial communities.

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