scholarly journals Massive Infection of Seabird Ticks with Bacterial Species Related to Coxiella burnetii

2014 ◽  
Vol 80 (11) ◽  
pp. 3327-3333 ◽  
Author(s):  
David A. Wilkinson ◽  
Muriel Dietrich ◽  
Camille Lebarbenchon ◽  
Audrey Jaeger ◽  
Céline Le Rouzic ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Bacterial Community ◽  
Tick Species ◽  
New Caledonia ◽  
Bacterial Pathogens ◽  
Bacterial Species ◽  
Horizontal Transmission ◽  
Western Indian Ocean ◽  
Content Type ◽  
Medical Importance

ABSTRACTSeabird ticks are known reservoirs of bacterial pathogens of medical importance; however, ticks parasitizing tropical seabirds have received less attention than their counterparts from temperate and subpolar regions. Recently,Rickettsia africaewas described to infect seabird ticks of the western Indian Ocean and New Caledonia, constituting the only available data on bacterial pathogens associated with tropical seabird tick species. Here, we combined a pyrosequencing-based approach with a classical molecular analysis targeting bacteria of potential medical importance in order to describe the bacterial community in two tropical seabird ticks,Amblyomma loculosumandCarios(Ornithodoros)capensis. We also investigated the patterns of prevalence and host specificity within the biogeographical context of the western Indian Ocean islands. The bacterial community of the two tick species was characterized by a strong dominance ofCoxiellaandRickettsia. Our data support a strictCoxiella-host tick specificity, a pattern resembling the one found forRickettsiaspp. in the same two seabird tick species. Both the high prevalence and stringent host tick specificity suggest that these bacteria may be tick symbionts with probable vertical transmission. Detailed studies of the pathogenicity of these bacteria will now be required to determine whether horizontal transmission can occur and to clarify their status as potential human pathogens. More generally, our results show that the combination of next generation sequencing with targeted detection/genotyping approaches proves to be efficient in poorly investigated fields where research can be considered to be starting from scratch.

scholarly journals Fate of Salmonella enterica and Enterohemorrhagic Escherichia coli Cells Artificially Internalized into Vegetable Seeds during Germination

2017 ◽  
Vol 84 (1) ◽  
Author(s):  
Da Liu ◽  
Yue Cui ◽  
Ronald Walcott ◽  
Jinru Chen
Keyword(s):  
Escherichia Coli ◽  
Salmonella Enterica ◽  
Bacterial Pathogens ◽  
Bacterial Species ◽  
Enterohemorrhagic Escherichia Coli ◽  
Human Pathogens ◽  
Gastrointestinal Infections ◽  
Tissue Samples ◽  
Content Type ◽  
Vegetable Seed

ABSTRACTVegetable seeds contaminated with bacterial pathogens have been linked to fresh-produce-associated outbreaks of gastrointestinal infections. This study was undertaken to observe the physiological behavior ofSalmonella entericaand enterohemorrhagicEscherichia coli(EHEC) cells artificially internalized into vegetable seeds during the germination process. Surface-decontaminated seeds of alfalfa, fenugreek, lettuce, and tomato were vacuum-infiltrated with four individual strains ofSalmonellaor EHEC. Contaminated seeds were germinated at 25°C for 9 days, and different sprout/seedling tissues were microbiologically analyzed every other day. The internalization ofSalmonellaand EHEC cells into vegetable seeds was confirmed by the absence of pathogens in seed-rinsing water and the presence of pathogens in seed homogenates after postinternalization seed surface decontamination. Results show that 317 (62%) and 343 (67%) of the 512 collected sprout/seedling tissue samples were positive forSalmonellaand EHEC, respectively. The averageSalmonellapopulations were significantly larger (P< 0.05) than the EHEC populations. Significantly largerSalmonellapopulations were recovered from the cotyledon and seed coat tissues, followed by the root tissues, but the mean EHEC populations from all sampled tissue sections were statistically similar, except in pregerminated seeds. ThreeSalmonellaand two EHEC strains had significantly larger cell populations on sprout/seedling tissues than other strains used in the study.Salmonellaand EHEC populations from fenugreek and alfalfa tissues were significantly larger than those from tomato and lettuce tissues. The study showed the fate of internalized human pathogens on germinating vegetable seeds and sprout/seedling tissues and emphasized the importance of using pathogen-free seeds for sprout production.IMPORTANCEThe internalization of microorganisms into vegetable seeds could occur naturally and represents a possible pathway of vegetable seed contamination by human pathogens. The present study investigated the ability of two important bacterial pathogens,Salmonellaand enterohemorrhagicEscherichia coli(EHEC), when artificially internalized into vegetable seeds, to grow and disseminate along vegetable sprouts/seedlings during germination. The data from the study revealed that the pathogen cells artificially internalized into vegetable seeds caused the contamination of different tissues of sprouts/seedlings and that pathogen growth on germinating seeds is bacterial species and vegetable seed-type dependent. These results further stress the necessity of using pathogen-free vegetable seeds for edible sprout production.

scholarly journals Litsea glutinosa (Indian laurel).

2020 ◽  
Author(s):  
Manuel Angel Duenas-Lopez
Keyword(s):  
South Africa ◽  
Indian Ocean ◽  
Pacific Islands ◽  
New Caledonia ◽  
Western Indian Ocean ◽  
Western Pacific ◽  
Native Plant ◽  
Tropical Regions ◽  
Native Plant Species ◽  
Litsea Glutinosa

Abstract Litsea glutinosa belongs to the family Lauraceae. It is a small- to medium-sized tree, 3-20 m tall, semi-evergreen, and fast-growing dioecious (Chowdhury et al., 2008; Ramana and Raju, 2019). It is native to India, South China to Malaysia, Australia and the western Pacific islands, and introduced and established in South Africa, the western Indian Ocean, and the south-western Pacific (New Caledonia), Mauritius and other tropical regions (Dassanayake, 1995). It has been introduced as a crop (Vos, 2004) and as an ornamental in tropical countries (EPPO, 2019). It has escaped from cultivation and is naturalized in some of the introduced areas. L. glutinosa has many uses in its area of origin as well as in some of its areas of introduction (ISSG, 2015). It is used principally as a binder for tablet formulations, and in the incense stick industry (Ramana and Raju, 2017).L. glutinosa is considered invasive in South Africa, where it is declared an invader plant (Henderson, 2001) and in the Indian Ocean (MacDonald et al., 1991; ISSG, 2015; PIER, 2019) on the islands of Mauritius (Mauritius Island and Rodrigues Island) (PIER, 2019) and Mayotte (Vos, 2004; ISSG, 2015; PIER, 2019). Jacq et al. (2005) do not consider L. glutinosa to be invasive globally, and ISSG (2015) considers it a small tree with high invasion potential, displacing native plant species in disturbed environments, although there is no evidence yet of its impact. It is classified by the IUCN (2019) as a species of Least Concern.

scholarly journals Novel Components of the Flagellar System in Epsilonproteobacteria

mBio ◽  
2014 ◽  
Vol 5 (3) ◽  
Author(s):  
Beile Gao ◽  
Maria Lara-Tejero ◽  
Matthew Lefebre ◽  
Andrew L. Goodman ◽  
Jorge E. Galán
Keyword(s):  
Helicobacter Pylori ◽  
Campylobacter Jejuni ◽  
Bacterial Pathogens ◽  
Bacterial Species ◽  
Flagellar Apparatus ◽  
Genetic Screen ◽  
Chemical Energy ◽  
Content Type ◽  
Molecular Bases ◽  
Insight Into

ABSTRACT Motility is essential for the pathogenesis of many bacterial species. Most bacteria move using flagella, which are multiprotein filaments that rotate propelled by a cell wall-anchored motor using chemical energy. Although some components of the flagellar apparatus are common to many bacterial species, recent studies have shown significant differences in the flagellar structures of different bacterial species. The molecular bases for these differences, however, are not understood. The flagella from epsilonproteobacteria, which include the bacterial pathogens Campylobacter jejuni and Helicobacter pylori, are among the most divergent. Using next-generation sequencing combined with transposon mutagenesis, we have conducted a comprehensive high-throughput genetic screen in Campylobacter jejuni, which identified several novel components of its flagellar system. Biochemical analyses detected interactions between the identified proteins and known components of the flagellar machinery, and in vivo imaging located them to the bacterial poles, where flagella assemble. Most of the identified new components are conserved within but restricted to epsilonproteobacteria. These studies provide insight into the divergent flagella of this group of bacteria and highlight the complexity of this remarkable structure, which has adapted to carry out its conserved functions in the context of widely diverse bacterial species. IMPORTANCE Motility is essential for the normal physiology and pathogenesis of many bacterial species. Most bacteria move using flagella, which are multiprotein filaments that rotate propelled by a motor that uses chemical energy as fuel. Although some components of the flagellar apparatus are common to many bacterial species, recent studies have shown significant divergence in the flagellar structures across bacterial species. However, the molecular bases for these differences are not understood. The flagella from epsilonproteobacteria, which include the bacterial pathogens Campylobacter jejuni and Helicobacter pylori, are among the most divergent. We conducted a comprehensive genetic screen in Campylobacter jejuni and identified several novel components of the flagellar system. These studies provide important information to understand how flagella have adapted to function in the context of widely diverse sets of bacterial species and bring unique insight into the evolution and function of this remarkable bacterial organelle.

scholarly journals Litsea glutinosa (Indian laurel).

2020 ◽  
Author(s):  
Manuel Angel Duenas-Lopez
Keyword(s):  
South Africa ◽  
Indian Ocean ◽  
Pacific Islands ◽  
New Caledonia ◽  
Western Indian Ocean ◽  
Western Pacific ◽  
Native Plant ◽  
Tropical Regions ◽  
Native Plant Species ◽  
Litsea Glutinosa

Abstract Litsea glutinosa belongs to the family Lauraceae. It is a small- to medium-sized tree, 3-20 m tall, semi-evergreen, and fast-growing dioecious (Chowdhury et al., 2008; Ramana and Raju, 2019). It is native to India, South China to Malaysia, Australia and the western Pacific islands, and introduced and established in South Africa, the western Indian Ocean, and the south-western Pacific (New Caledonia), Mauritius and other tropical regions (Dassanayake, 1995). It has been introduced as a crop (Vos, 2004) and as an ornamental in tropical countries (EPPO, 2019). It has escaped from cultivation and is naturalized in some of the introduced areas. L. glutinosa has many uses in its area of origin as well as in some of its areas of introduction (ISSG, 2015). It is used principally as a binder for tablet formulations, and in the incense stick industry (Ramana and Raju, 2017). L. glutinosa is considered invasive in South Africa, where it is declared an invader plant (Henderson, 2001) and in the Indian Ocean (MacDonald et al., 1991; ISSG, 2015; PIER, 2019) on the islands of Mauritius (Mauritius Island and Rodrigues Island) (PIER, 2019) and Mayotte (Vos, 2004; ISSG, 2015; PIER, 2019). Jacq et al. (2005) do not consider L. glutinosa to be invasive globally, and ISSG (2015) considers it a small tree with high invasion potential, displacing native plant species in disturbed environments, although there is no evidence yet of its impact. It is classified by the IUCN (2019) as a species of Least Concern.

scholarly journals Fibropapillomatosis infection in a population of green turtles at Watamu Bay, Kenya

2021 ◽  
Vol 20 (1) ◽  
pp. 111-123
Author(s):  
Sharon M. Jones ◽  
Itamar Caspi ◽  
Charles Lucas
Keyword(s):  
Indian Ocean ◽  
Horizontal Transmission ◽  
Western Indian Ocean ◽  
Chelonia Mydas ◽  
Infection Prevalence ◽  
Marine Biota ◽  
Community Factors ◽  
Green Turtles ◽  
Wide Range ◽  
Kenyan Coast

Anthropogenic stressors from onshore and offshore activities can act as driving factors of disease for a wide range of marine organisms. Green turtles (Chelonia mydas) are prominently afflicted with a tumour-causing disease known as fibropapillomatosis (FP) caused by the chelonid alphaherpesvirus ChHV5. Previous studies indicate that pathways of FP transmission may be genetic (vertical transmission) or linked to causal factors in a turtle’s environment (horizontal transmission). In this paper patterns of FP prevalence were examined in 10,896 records of green turtles caught or found stranded around Watamu Bay, Kenya, between 2003 – 2020. Findings were focused on locational and seasonal factors that may potentially influence infection. The findings show that FP prevalence varies significantly on an annual basis. Location significantly influenced infection prevalence, with prevalence higher in open ocean sites than sites located within the creek. Infection prevalence was highest at sites around the creek mouth and north of the creek mouth, with both regions exhibiting disparate annual patterns of infection. This paper is the first to examine long-term trends of FP prevalence in-depth in this region and has implications for the health of turtles and marine biota found along the Kenyan coast, and potentially within the wider Western Indian Ocean region. The findings emphasize the need to distinguish the infection pathways of causative agents via: i) further examination of the links between infection and environmental and/or biont community factors; and ii) the collection of data pertinent to the genetic diversity of green turtles and associated ChHV5 viral strains occurring in the Western Indian Ocean.

scholarly journals Phyllosphere Bacterial Community of Floating Macrophytes in Paddy Soil Environments as Revealed by Illumina High-Throughput Sequencing

2014 ◽  
Vol 81 (2) ◽  
pp. 522-532 ◽  
Author(s):  
Wan-Ying Xie ◽  
Jian-Qiang Su ◽  
Yong-Guan Zhu
Keyword(s):  
Bacterial Community ◽  
Paddy Soil ◽  
Bacterial Communities ◽  
Bacterial Species ◽  
Rrna Gene ◽  
Core Microbiome ◽  
Content Type ◽  
Soil Ecosystems ◽  
Α Diversity ◽  
Floating Macrophytes

ABSTRACTThe phyllosphere of floating macrophytes in paddy soil ecosystems, a unique habitat, may support large microbial communities but remains largely unknown. We tookWolffia australianaas a representative floating plant and investigated its phyllosphere bacterial community and the underlying driving forces of community modulation in paddy soil ecosystems using Illumina HiSeq 2000 platform-based 16S rRNA gene sequence analysis. The results showed that the phyllosphere ofW. australianaharbored considerably rich communities of bacteria, withProteobacteriaandBacteroidetesas the predominant phyla. The core microbiome in the phyllosphere contained genera such asAcidovorax,Asticcacaulis,Methylibium, andMethylophilus. Complexity of the phyllosphere bacterial communities in terms of class number and α-diversity was reduced compared to those in corresponding water and soil. Furthermore, the bacterial communities exhibited structures significantly different from those in water and soil. These findings and the following redundancy analysis (RDA) suggest that species sorting played an important role in the recruitment of bacterial species in the phyllosphere. The compositional structures of the phyllosphere bacterial communities were modulated predominantly by water physicochemical properties, while the initial soil bacterial communities had limited impact. Taken together, the findings from this study reveal the diversity and uniqueness of the phyllosphere bacterial communities associated with the floating macrophytes in paddy soil environments.

scholarly journals A peek into Western Indian Ocean microbial richness: a pilot for a coral microbiome study

2019 ◽  
Author(s):  
Sammy Wambua ◽  
Hadrien Gourlé ◽  
Etienne P. de Villiers ◽  
Joyce Ngoi ◽  
Angus Macdonald ◽  
...  
Keyword(s):  
Coral Reef ◽  
Indian Ocean ◽  
Bacterial Species ◽  
Alpha Diversity ◽  
Environmental Dna ◽  
Western Indian Ocean ◽  
Natural Ecosystems ◽  
Tropical Water ◽  
Coral Microbiome ◽  
Essential Components

AbstractMicrobial communities are essential components of natural ecosystems. Of the global oceans, the Indian Ocean remains the least studied in terms of its microbial diversity, despite it being a highly dynamic tropical water body. Metagenomics methods have significantly advanced studies in marine microbial ecology in recent years. Preliminary metabarcoding assessments are recommended to mitigate against the associated costs, prior to the metagenomics study, to give an impression of the diversity expected and determine the sequencing effort required.We report here the first metabarcoding survey of bacterial diversity of the western Indian Ocean (WIO) using samples used for optimizing environmental DNA (eDNA) isolation as pilot experiment for a metagenomic study investigating the coral-reef microbiome of the region. Sampling of water and sediment samples was done near-shore sublittoral and within the coral reef.About 3,000 microbial ribotypes were inferred, from which 41 phyla were uncovered. Sediments registered higher alpha diversity than seawater samples. The phylum Proteobacteria was dominant with its members constituting over 60% of the ribosomal sequence variants (RSVs). The other abundant bacteria were members of Bacteroidetes and Cyanobacteria phyla. We identified bacterial species with potential broad biotechnological applications, underscoring the WIO’s richness and the usefulness of eDNA metabarcoding approaches in bioprospecting as well as monitoring and/or surveying marine ecosystems.

scholarly journals ALactobacillus-Deficient Vaginal Microbiota Dominates Postpartum Women in Rural Malawi

2018 ◽  
Vol 84 (6) ◽  
Author(s):  
Ronan Doyle ◽  
Austridia Gondwe ◽  
Yue-Mei Fan ◽  
Kenneth Maleta ◽  
Per Ashorn ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Birth Outcomes ◽  
Bacterial Species ◽  
Disease Status ◽  
Vaginal Microbiota ◽  
Gardnerella Vaginalis ◽  
Adverse Birth Outcomes ◽  
Content Type ◽  
Inflammatory Conditions ◽  
State Type

ABSTRACTThe bacterial community found in the vagina is an important determinant of a woman's health and disease status. A healthy vaginal microbiota is associated with low species richness and a high proportion of one of a number of differentLactobacillusspp. When disrupted, the resulting abnormal vaginal microbiota is associated with a number of disease states and poor pregnancy outcomes. Studies up until now have concentrated on relatively small numbers of American and European populations that may not capture the full complexity of the community or adequately predict what constitutes a healthy microbiota in all populations. In this study, we sampled and characterized the vaginal microbiota found on vaginal swabs taken postpartum from a cohort of 1,107 women in rural Malawi. We found a population dominated byGardnerella vaginalisand devoid of the most common vaginalLactobacillusspecies, even if the vagina was sampled over a year postpartum. ThisLactobacillus-deficient anaerobic community, commonly labeled community state type (CST) 4, could be subdivided into four further communities. ALactobacillus iners-dominated vaginal microbiota became more common the longer after delivery the vagina was sampled, butG. vaginalisremained the dominant organism. These results outline the difficulty in all-encompassing definitions of what a healthy or abnormal postpartum vaginal microbiota is. Previous identification of community state types and associations among bacterial species, bacterial vaginosis, and adverse birth outcomes may not represent the complex heterogeneity of the microbiota present. (This study has been registered at ClinicalTrials.gov as NCT01239693.)IMPORTANCEA bacterial community in the vaginal tract is dominated by a small number ofLactobacillusspecies, and when not present there is an increased incidence of inflammatory conditions and adverse birth outcomes. A switch to a vaginal bacterial community lacking inLactobacillusspecies is common after pregnancy. In this study, we characterized the postpartum vaginal bacterial community of a large group of women from a resource-poor, undersampled population in rural Malawi. The majority of women were found to have aLactobacillus-deficient community, and even when sampled a year after delivery the majority of women still did not haveLactobacilluspresent in their vaginal microbiota. The effect of becoming pregnant again for those who do not revert to aLactobacillus-dominant community is unknown, and this could suggest that not allLactobacillus-deficient community structures are adverse. A better understanding of this complex community state type is needed.

scholarly journals Bdellovibrio and Like Organisms Enhanced Growth and Survival of Penaeus monodon and Altered Bacterial Community Structures in Its Rearing Water

2014 ◽  
Vol 80 (20) ◽  
pp. 6346-6354 ◽  
Author(s):  
Huanhuan Li ◽  
Cheng Chen ◽  
Qiuping Sun ◽  
Renliang Liu ◽  
Junpeng Cai
Keyword(s):  
Bacterial Community ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Bacterial Species ◽  
Penaeus Monodon ◽  
Pcr Amplification ◽  
Rrna Gene ◽  
Community Structures ◽  
Bacterial Strains ◽  
Content Type ◽  
Growth And Survival

ABSTRACTIn this study, a 96-h laboratory reduction test was conducted with strain BDHSH06 (GenBank accession no.EF011103) as the test strain forBdellovibrioand like organisms (BALOs) and 20 susceptible marine bacterial strains forming microcosms as the targets. The results showed that BDHSH06 reduced the levels of approximately 50% of prey bacterial strains within 96 h in the seawater microcosms. An 85-day black tiger shrimp (Penaeus monodon) rearing experiment was performed. The shrimp survival rate, body length, and weight in the test tanks were 48.1% ± 1.2%, 99.8 ± 10.0 mm, and 6.36 ± 1.50 g, respectively, which were values significantly (P< 0.05) higher than those for the control,viz., 31.0% ± 2.1%, 86.0 ± 11.1 mm, and 4.21 ± 1.56 g, respectively. With the addition of BDHSH06, total bacterial andVibrionumbers were significantly reduced (P< 0.05) by 1.3 to 4.5 log CFU · ml−1and CFU · g−1in both water and shrimp intestines, respectively, compared to those in the control. The effect of BDHSH06 on bacterial community structures in the rearing water was also examined using PCR amplification of the 16S rRNA gene and denaturing gradient gel electrophoresis (DGGE). The DGGE profiles of rearing water samples from the control and test tanks revealed that the amounts of 44% of the bacterial species were reduced when BDHSH06 was added to the rearing water over the 85-day rearing period, and among these, approximately 57.1% were nonculturable. The results of this study demonstrated that BDHSH06 can be used as a biocontrol/probiotic agent inP. monodonculture.

Constant global vigilance is key to containing piracy

2016 ◽  
Keyword(s):  
Indian Ocean ◽  
Hot Spots ◽  
Western Indian Ocean ◽  
Shipping Industry ◽  
Concerted Action ◽  
Protective Measures ◽  
Content Type ◽  
International Shipping ◽  
The World

Subject The world's 'hot-spots' for piracy. Significance From time to time, and in various parts of the world, piracy has become serious enough to prompt concerted action against it. Somali piracy at its height was a threat to major international shipping lanes in the Western Indian Ocean. Impacts Curbing Somali piracy will save the shipping industry the costs of protective measures, faster and diverted steaming, and insurance. Violence against seafarers could become so serious as to deter them from signing on for some voyages. That could lead shipowners to turn to inexperienced staff desperate for employment. Some fear a link between piracy and terrorism; this is controversial.

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