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排序方式: 共有1317条查询结果,搜索用时 15 毫秒
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Ferguson AS Huang WE Lawson KA Doherty R Gibert O Dickson KW Whiteley AS Kulakov LA Thompson IP Kalin RM Larkin MJ 《Journal of applied microbiology》2007,102(5):1227-1238
AIMS: To investigate the distribution of a polymicrobial community of biodegradative bacteria in (i) soil and groundwater at a former manufactured gas plant (FMGP) site and (ii) in a novel SEquential REactive BARrier (SEREBAR) bioremediation process designed to bioremediate the contaminated groundwater. METHODS AND RESULTS: Culture-dependent and culture-independent analyses using denaturing gradient gel electrophoresis (DGGE) and polymerase chain reaction (PCR) for the detection of 16S ribosomal RNA gene and naphthalene dioxygenase (NDO) genes of free-living (planktonic groundwater) and attached (soil biofilm) samples from across the site and from the SEREBAR process was applied. Naphthalene arising from groundwater was effectively degraded early in the process and the microbiological analysis indicated a dominant role for Pseudomonas and Comamonas in its degradation. The microbial communities appeared highly complex and diverse across both the sites and in the SEREBAR process. An increased population of naphthalene degraders was associated with naphthalene removal. CONCLUSION: The distribution of micro-organisms in general and naphthalene degraders across the site was highly heterogeneous. Comparisons made between areas contaminated with polycyclic aromatic hydrocarbons (PAH) and those not contaminated, revealed differences in the microbial community profile. The likelihood of noncultured bacteria being dominant in mediating naphthalene removal was evident. SIGNIFICANCE AND IMPACT OF THE STUDY: This work further emphasizes the importance of both traditional and molecular-based tools in determining the microbial ecology of contaminated sites and highlights the role of noncultured bacteria in the process. 相似文献
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David J. Yurkowski Marie Auger‐Mth Mark L. Mallory Sarah N. P. Wong Grant Gilchrist Andrew E. Derocher Evan Richardson Nicholas J. Lunn Nigel E. Hussey Marianne Marcoux Ron R. Togunov Aaron T. Fisk Lois A. Harwood Rune Dietz Aqqalu Rosing‐Asvid Erik W. Born Anders Mosbech Jrme Fort David Grmillet Lisa Loseto Pierre R. Richard John Iacozza Frankie Jean‐Gagnon Tanya M. Brown Kristin H. Westdal Jack Orr Bernard LeBlanc Kevin J. Hedges Margaret A. Treble Steven T. Kessel Paul J. Blanchfield Shanti Davis Mark Maftei Nora Spencer Laura McFarlane‐Tranquilla William A. Montevecchi Blake Bartzen Lynne Dickson Christine Anderson Steven H. Ferguson 《Diversity & distributions》2019,25(3):328-345
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Earnest Njih Tabah Dickson Shey Nsagha Anne-Cécile Zoung-Kanyi Bissek Alfred Kongnyu Njamnshi Martin W. Bratschi Gerd Pluschke Alphonse Um Boock 《PLoS neglected tropical diseases》2016,10(1)
BackgroundCameroon is endemic for Buruli ulcer (BU) and organised institutional BU control began in 2002. The objective was to describe the evolution, achievements and challenges of the national BU control programme (NBUCP) and to make suggestions for scaling up the programme.MethodsWe analysed collated data on BU from 2001 to 2014 and reviewed activity reports NBUCP in Cameroon. Case-detection rates and key BU control indicators were calculated and plotted on a time scale to determine trends in performance. A linear regression analysis of BU detection rate from 2005–2014 was done. The regression coefficient was tested statistically for the significance in variation of BU detection rate.Conclusion/SignificanceAlthough institutional BU control Cameroon only began 30 years after the first cases were reported in 1969, a number of milestones have been attained. These would serve as stepping stones for charting the way forward and improving upon control activities in the country if the major challenge of resource allocation is dealt with. 相似文献
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Sphingolipid long-chain-base auxotrophs of Saccharomyces cerevisiae: genetics, physiology, and a method for their selection. 下载免费PDF全文
W J Pinto B Srinivasan S Shepherd A Schmidt R C Dickson R L Lester 《Journal of bacteriology》1992,174(8):2565-2574
A selection method for sphingolipid long-chain-base auxotrophs of Saccharomyces cerevisiae was devised after observing that strains that require a long-chain base for growth become denser when starved for this substance. Genetic analysis of over 60 such strains indicated only two complementation classes, lcb1 and lcb2. Mutant strains from each class grew equally well with 3-ketodihydrosphingosine, erythrodihydrosphingosine or threodihydrosphingosine, or phytosphingosine. Since these metabolites represent the first, second, and last components, respectively, of the long-chain-base biosynthetic pathway, it is likely that the LCB1 and LCB2 genes are involved in the first step of long-chain-base synthesis. The results of long-chain-base starvation in the Lcb- strains suggest that one or more sphingolipids have a vital role in S. cerevisiae. Immediate sequelae of long-chain-base starvation were loss of viability, exacerbated in the presence of alpha-cyclodextrin, and loss of phosphoinositol sphingolipid synthesis but not phosphatidylinositol synthesis. Loss of viability with long-chain-base starvation could be prevented by also blocking either protein or nucleic acid synthesis. Without a long-chain-base, cell division, dry mass accumulation, and protein synthesis continued at a diminished rate and were further inhibited by the detergent Tergitol. The cell density increase induced by long-chain-base starvation is thus explained as a differential loss of cell division and mass accumulation. Long-chain-base starvation in Lcb- S. cerevisiae and inositol starvation of Inos- S. cerevisiae share common features: an increase in cell density and a loss of cell viability overcome by blocking macromolecular synthesis. 相似文献
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