The Experts below are selected from a list of 62592 Experts worldwide ranked by ideXlab platform
Frédérique Barloy-hubler - One of the best experts on this subject based on the ideXlab platform.
-
Porphyromonas spp. have an extensive host range in ill and healthy individuals and an unexpected environmental distribution: A systematic review and meta-analysis
Anaerobe, 2020Co-Authors: Luis Acuña-amador, Frédérique Barloy-hublerAbstract:Studies on the anaerobic bacteria Porphyromonas, mainly focused on P. gingivalis, have revealed new Bacterial Structures, metabolic pathways, and physiologic functionalities. Porphyromonas are mainly described as being associated with mammals and involved in chronic oral infections and secondary pathologies such as cancers or neurodegenerative diseases. In this review, we collected and analyzed information regarding Porphyromonas isolation sites and associated conditions and showed that Porphyromonas are detected in numerous pristine and anthropic environments and that their host range appears wider than previously believed, including aquatic animals, arthropods, and birds, even if their predominant hosts remain humans, pets, and farm animals. Our analyses also revealed their presence in multiple organs and in a substantial proportion of healthy contexts. Overall, the growing numbers of microbiota studies have allowed unprecedented advances in the understanding of Porphyromonas ecology but raise questions regarding their phylogenic assignment. In conclusion, this systematic and meta-analysis provides an overview of current knowledge regarding Porphyromonas ecological distribution and encourages additional research to fill the knowledge gaps to better understand their environmental distribution and inter- and intra-species transmission.
Benjamin A. Solis - One of the best experts on this subject based on the ideXlab platform.
-
Uncharacterized Bacterial Structures Revealed by Electron Cryotomography.
Journal of bacteriology, 2017Co-Authors: Megan J. Dobro, Catherine M. Oikonomou, Aidan Piper, John Cohen, Kylie Guo, Taylor Jensen, Jahan Tadayon, Joseph Donermeyer, Yeram Park, Benjamin A. SolisAbstract:Electron cryotomography (ECT) can reveal the native structure and arrangement of macromolecular complexes inside intact cells. This technique has greatly advanced our understanding of the ultrastructure of Bacterial cells. We now view bacteria as structurally complex assemblies of macromolecular machines rather than as undifferentiated bags of enzymes. To date, our group has applied ECT to nearly 90 different Bacterial species, collecting more than 15,000 cryotomograms. In addition to known Structures, we have observed, to our knowledge, several uncharacterized features in these tomograms. Some are completely novel Structures; others expand the features or species range of known structure types. Here, we present a survey of these uncharacterized Bacterial Structures in the hopes of accelerating their identification and study, and furthering our understanding of the structural complexity of Bacterial cells.IMPORTANCE Bacteria are more structurally complex than is commonly appreciated. Here we present a survey of previously uncharacterized Structures that we observed in Bacterial cells by electron cryotomography, Structures that will initiate new lines of research investigating their identities and roles.
-
Uncharacterized Bacterial Structures revealed by electron cryotomography
2017Co-Authors: Megan J. Dobro, Catherine M. Oikonomou, Aidan Piper, John Cohen, Kylie Guo, Taylor Jensen, Jahan Tadayon, Joseph Donermeyer, Yeram Park, Benjamin A. SolisAbstract:Electron cryotomography (ECT) can reveal the native structure and arrangement of macromolecular complexes inside intact cells. This technique has greatly advanced our understanding of the ultrastructure of Bacterial cells. Rather than undifferentiated bags of enzymes, we now view bacteria as structurally complex assemblies of macromolecular machines. To date, our group has applied ECT to nearly 90 different Bacterial species, collecting more than 15,000 cryotomograms. In addition to known Structures, we have observed several, to our knowledge, uncharacterized features in these tomograms. Some are completely novel Structures; others expand the features or species range of known structure types. Here we present a survey of these uncharacterized Bacterial Structures in the hopes of accelerating their identification and study, and furthering our understanding of the structural complexity of Bacterial cells.
Guangfeng Yang - One of the best experts on this subject based on the ideXlab platform.
-
Kinetic characteristics and Bacterial Structures in biofilm reactors with pre-cultured biofilm for source water pretreatment
International Biodeterioration & Biodegradation, 2017Co-Authors: Lijuan Feng, Mu Jun, Sun Jingya, Yun Kong, Jing Wang, Liang Zhu, Guangfeng YangAbstract:The growth and accumulation of functional bacteria were limited due to the deficiency of substrates in biofilm reactors for source water pretreatment. In this study, pre-cultured biofilm (PCB) formed on different carriers was used to treat oligotrophic source water, and the kinetic characteristics and Bacterial Structures was evaluated under realistic conditions. Experimental results showed that PCB formed under substrate-enhanced conditions decreased substrate affinity of biofilm, but effectively improved the operation performance of biofilm reactors. In particularly, biofilm formed on elastic stereo media had the lowest apparent half-saturation coefficient (Ks) for substrates, which was more easily to accommodate oligotrophic niche. Interestingly, biodiversity of biofilm was obviously increased after long-term exposure to oligotrophic niche, and decreased functional bacteria were replaced by others with similar function. Basically, Proteobacteria and Planctomycetes were dominant in biofilm samples under both substrate-enhanced and oligotrophic conditions.
F. G. Ferris - One of the best experts on this subject based on the ideXlab platform.
-
characterization of bacteriogenic iron oxide deposits from axial volcano juan de fuca ridge northeast pacific ocean
Geomicrobiology Journal, 2003Co-Authors: C. B. Kennedy, Steven D. Scott, F. G. FerrisAbstract:Iron oxides from the caldera of Axial Volcano, a site of hydrothermal vent activity along the Juan de Fuca Ridge, are characterized by abundant Bacterial Structures that closely resemble the sheaths of Leptothrix ochracea , the stalks of Gallionella ferruginea , and the filaments of a novel iron oxidizing PV-1 strain. These bacteria are commonly associated with iron-oxide precipitates and are proposed to play two causal roles in the formation of iron oxides at Axial Volcano. First, by increasing the rate of Fe 2+ oxidation, and second, by lowering the concentration of Fe 3+ required for precipitation by providing a reactive surface for heterogeneous nucleation. Rapid rates of oxidation and precipitation caused by the bacteria likely contribute to the poorly ordered nature of the iron oxides, determined to be primarily 2-line ferrihydrite, and in one case, poorly ordered goethite. The iron-oxide precipitates consist dominantly of iron, silicon (mostly diatoms), and organic carbon with a suite of sorbed tra...
-
Ultrastructure and potential sub-seafloor evidence of bacteriogenic iron oxides from Axial Volcano, Juan de Fuca Ridge, north-east Pacific Ocean
FEMS microbiology ecology, 2003Co-Authors: C. B. Kennedy, Steven D. Scott, F. G. FerrisAbstract:Iron oxides from the caldera of Axial Volcano, a site of hydrothermal vent activity along the Juan de Fuca Ridge, were found to consist predominantly of microbial Structures in hydrated whole mounts examined using an environmental scanning electron microscope. Novel observations were made of the iron oxides revealing the spatial relationships of the bacteria within to be more consistent with microbial mats than mineral precipitates. The Bacterial Structures are attributed to the sheaths of Leptothrix ochracea, the stalks of Gallionella ferruginea, and the filaments of a novel iron oxidizing PV-1 strain, based on the distinctive morphological characteristics of these three bacteria. Energy dispersive X-ray spectroscopy revealed the presence and distribution of Fe, Si, and Cl on the Bacterial sheaths, stalks and filaments. The iron oxides were identified by X-ray diffraction to be two-line ferrihydrite, a poorly ordered iron oxyhydroxide. Adsorption of Si in particular to two-line ferrihydrite likely contributes to its stability on the seafloor, and might also be a preservation mechanism creating microfossils of the Bacterial Structures encrusted with ferrihydrite. Presumptive evidence of the sub-seafloor presence of L. ochracea, G. ferruginea and PV-1 at Axial Volcano was obtained from the presence of these bacteria on a trap that had been placed within an active vent, and also in a vent fluid sample. If indeed these bacteria are present in the sub-seafloor, it may be an indication that the surface expression of iron oxide deposits at Axial Volcano is minimal in comparison to what exists beneath the seafloor.
Luis Acuña-amador - One of the best experts on this subject based on the ideXlab platform.
-
Porphyromonas spp. have an extensive host range in ill and healthy individuals and an unexpected environmental distribution: A systematic review and meta-analysis
Anaerobe, 2020Co-Authors: Luis Acuña-amador, Frédérique Barloy-hublerAbstract:Studies on the anaerobic bacteria Porphyromonas, mainly focused on P. gingivalis, have revealed new Bacterial Structures, metabolic pathways, and physiologic functionalities. Porphyromonas are mainly described as being associated with mammals and involved in chronic oral infections and secondary pathologies such as cancers or neurodegenerative diseases. In this review, we collected and analyzed information regarding Porphyromonas isolation sites and associated conditions and showed that Porphyromonas are detected in numerous pristine and anthropic environments and that their host range appears wider than previously believed, including aquatic animals, arthropods, and birds, even if their predominant hosts remain humans, pets, and farm animals. Our analyses also revealed their presence in multiple organs and in a substantial proportion of healthy contexts. Overall, the growing numbers of microbiota studies have allowed unprecedented advances in the understanding of Porphyromonas ecology but raise questions regarding their phylogenic assignment. In conclusion, this systematic and meta-analysis provides an overview of current knowledge regarding Porphyromonas ecological distribution and encourages additional research to fill the knowledge gaps to better understand their environmental distribution and inter- and intra-species transmission.