scholarly journals Monitoring Biofilm Formation and Microbial Interactions that May Occur During a Salmonella Contamination Incident across the Network of a Water Bottling Plant

2019 ◽  
Vol 7 (8) ◽  
pp. 236
Author(s):  
Karampoula ◽  
Doulgeraki ◽  
Fotiadis ◽  
Tampakaki ◽  
Nychas
Keyword(s):  
Bacterial Communities ◽  
Biofilm Formation ◽  
Fluorescent Protein ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Yellow Fluorescent Protein ◽  
Foodborne Pathogen ◽  
Microbial Interactions ◽  
Enhanced Yellow Fluorescent Protein ◽  
Serovar Typhimurium ◽  
Gradient Gel Electrophoresis

The present study aims to monitor the ability of Salmonella to colonize and compete as a member of the mixed species biofilm within key points at a water bottling plant, in case of a contamination incident with this major foodborne pathogen. To achieve this goal, bacterial communities throughout the production line were collected and their identities were investigated by microbial counts and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). These bacterial communities alone or along with constructed Salmonella enterica serovar Typhimurium (ST) fluorescence-based bioreporters were left to form a biofilm on stainless steel for 6 days at 20 °C. ST bioreporters were constructed by introducing plasmids expressing EYFP (enhanced yellow fluorescent protein) fusions of the genes csgB, csrA, sspH2, and fliD into ST 14028S. The bead vortexing-plate counting method was applied for the enumeration of the biofilm population, while the behavior of the bioreporters was evaluated by fluorescence microscopy. From a set of 16 samples that were collected from the plant, species of Citrobacter, Staphylococcus, Pseudomonas, Bacillus, and Exiguobacterium were identified. The presence of these indigenous bacteria neither inhibited nor enhanced the biofilm formation of ST in mixed bacterial communities (p > 0.05). Furthermore, the csrA-based bioreporter was shown to be induced in multispecies biofilms with Citrobacter. In conclusion, this study enhanced our knowledge of bacterial interactions occurring within a biofilm in a water bottling plant.

scholarly journals Impact of Intensive Land-Based Fish Culture in Qingdao, China, on the Bacterial Communities in Surrounding Marine Waters and Sediments

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Qiufen Li ◽  
Yan Zhang ◽  
David Juck ◽  
Nathalie Fortin ◽  
Charles W. Greer
Keyword(s):  
Bacterial Communities ◽  
Gel Electrophoresis ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Fish Culture ◽  
Fish Ponds ◽  
Marine Area ◽  
Gradient Gel Electrophoresis ◽  
Reducing Bacteria ◽  
The Impact ◽  
Nitrate Reducing Bacteria

The impact of intensive land-based fish culture in Qingdao, China, on the bacterial communities in surrounding marine environment was analyzed. Culture-based studies showed that the highest counts of heterotrophic, ammonium-oxidizing, nitrifying, and nitrate-reducing bacteria were found in fish ponds and the effluent channel, with lower counts in the adjacent marine area and the lowest counts in the samples taken from 500 m off the effluent channel. Denaturing gradient gel electrophoresis (DGGE) analysis was used to assess total bacterial diversity. Fewer bands were observed from the samples taken from near the effluent channel compared with more distant sediment samples, suggesting that excess nutrients from the aquaculture facility may be reducing the diversity of bacterial communities in nearby sediments. Phylogenetic analysis of the sequenced DGGE bands indicated that the bacteria community of fish-culture-associated environments was mainly composed of Flavobacteriaceae, gamma- and deltaproteobacteria, including generaGelidibacter, Psychroserpen, Lacinutrix,andCroceimarina.

scholarly journals Genetic and transgenic reagents for Drosophila simulans, D. mauritiana, D. yakuba, D. santomea and D. virilis

2016 ◽  
Author(s):  
David L. Stern ◽  
Justin Crocker ◽  
Yun Ding ◽  
Nicolas Frankel ◽  
Gretchen Kappes ◽  
...  
Keyword(s):  
Fluorescent Protein ◽  
Integration Site ◽  
Yellow Fluorescent Protein ◽  
Model Systems ◽  
Enhanced Yellow Fluorescent Protein ◽  
Functional Studies ◽  
Site Specific Integration ◽  
Genetic Strains ◽  
Fluorescent Molecules ◽  
Integration Efficiency

AbstractSpecies of the Drosophila melanogaster species subgroup, including the species D. simulans, D. mauritiana, D. yakuba, and D. santomea, have long served as model systems for studying evolution. Studies in these species have been limited, however, by a paucity of genetic and transgenic reagents. Here we describe a collection of transgenic and genetic strains generated to facilitate genetic studies within and between these species. We have generated many strains of each species containing mapped piggyBac transposons including an enhanced yellow fluorescent protein gene expressed in the eyes and a phiC31 attP site-specific integration site. We have tested a subset of these lines for integration efficiency and reporter gene expression levels. We have also generated a smaller collection of other lines expressing other genetically encoded fluorescent molecules in the eyes and a number of other transgenic reagents that will be useful for functional studies in these species. In addition, we have mapped the insertion locations of 58 transposable elements in D. virilis that will be useful for genetic mapping studies.

scholarly journals Pancreatic islet function in a transgenic mouse expressing fluorescent protein

2005 ◽  
Vol 186 (2) ◽  
pp. 333-341 ◽  
Author(s):  
Daniel Nyqvist ◽  
Göran Mattsson ◽  
Martin Köhler ◽  
Varda Lev-Ram ◽  
Arne Andersson ◽  
...  
Keyword(s):  
Pancreatic Islet ◽  
Glucose Homeostasis ◽  
Fluorescent Protein ◽  
Regional Blood Flow ◽  
Animal Health ◽  
Yellow Fluorescent Protein ◽  
Islet Function ◽  
Enhanced Yellow Fluorescent Protein ◽  
Isolated Pancreatic Islets ◽  
Arterial Blood

Pancreatic islet function and glucose homeostasis have been characterized in the transgenic YC-3.0 mouse, which expresses the yellow chameleon 3.0 (YC-3.0) protein under the control of the β-actin and the cytomegalovirus promoters. Fluorescence from the enhanced yellow fluorescent protein (EYFP), one part of the yellow chameleon protein, was used as a reporter of transgene expression. EYFP was expressed in different quantities throughout most cell types, including islet endocrine and stromal cells. No adverse effects of the transgene on animal health, growth or fertility were observed. Likewise, in vivo glucose homeostasis, mean arterial blood pressure and regional blood flow values were normal. Furthermore, the transgenic YC-3.0 mouse had a normal β-cell volume and mass as well as glucose-stimulated insulin release in vitro, compared with the C57BL/6 control mouse. Isolated islets from YC-3.0 animals continuously expressed the transgene and reversed hyperglycemia when transplanted under the renal capsule of alloxan-diabetic nude mice. We conclude that isolated pancreatic islets from YC-3.0 animals implanted into recipients without any EYFP expression, constitute a novel and versatile model for studies of islet engraftment.

scholarly journals C-terminal eYFP fusion impairs Escherichia coli MinE function

Open Biology ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 200010
Author(s):  
Navaneethan Palanisamy ◽  
Mehmet Ali Öztürk ◽  
Emir Bora Akmeriç ◽  
Barbara Di Ventura
Keyword(s):  
Escherichia Coli ◽  
In Silico ◽  
Fluorescent Protein ◽  
Fluorescent Proteins ◽  
Yellow Fluorescent Protein ◽  
Time Lapse ◽  
Enhanced Yellow Fluorescent Protein ◽  
Min Proteins

The Escherichia coli Min system plays an important role in the proper placement of the septum ring at mid-cell during cell division. MinE forms a pole-to-pole spatial oscillator with the membrane-bound ATPase MinD, resulting in MinD concentration being the lowest at mid-cell. MinC, the direct inhibitor of the septum initiator protein FtsZ, forms a complex with MinD at the membrane, mirroring its polar gradients. Therefore, MinC-mediated FtsZ inhibition occurs away from mid-cell. Min oscillations are often studied in living cells by time-lapse microscopy using fluorescently labelled Min proteins. Here, we show that, despite permitting oscillations to occur in a range of protein concentrations, the enhanced yellow fluorescent protein (eYFP) C-terminally fused to MinE impairs its function. Combining in vivo , in vitro and in silico approaches, we demonstrate that eYFP compromises the ability of MinE to displace MinC from MinD, to stimulate MinD ATPase activity and to directly bind to the membrane. Moreover, we reveal that MinE-eYFP is prone to aggregation. In silico analyses predict that other fluorescent proteins are also likely to compromise several functionalities of MinE, suggesting that the results presented here are not specific to eYFP.

scholarly journals Acidocalcisomes and Polyphosphate Granules Are Different Subcellular Structures in Agrobacterium tumefaciens

2020 ◽  
Vol 86 (8) ◽  
Author(s):  
Celina Frank ◽  
Dieter Jendrossek
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Fluorescent Dyes ◽  
Fluorescent Protein ◽  
Ralstonia Eutropha ◽  
Yellow Fluorescent Protein ◽  
Eukaryotic Cells ◽  
Enhanced Yellow Fluorescent Protein ◽  
Content Type ◽  
Polyphosphate Granules

ABSTRACT Acidocalcisomes are membrane-enclosed, polyphosphate-containing acidic organelles in lower Eukaryota but have also been described for Agrobacterium tumefaciens (M. Seufferheld, M. Vieira, A. Ruiz, C. O. Rodrigues, S. Moreno, and R. Docampo, J Biol Chem 278:29971–29978, 2003, https://doi.org/10.1074/jbc.M304548200). This study aimed at the characterization of polyphosphate-containing acidocalcisomes in this alphaproteobacterium. Unexpectedly, fluorescence microscopic investigation of A. tumefaciens cells using fluorescent dyes and localization of constructed fusions of polyphosphate kinases (PPKs) and of vacuolar H+-translocating pyrophosphatase (HppA) with enhanced yellow fluorescent protein (eYFP) suggested that acidocalcisomes and polyphosphate are different subcellular structures. Acidocalcisomes and polyphosphate granules were frequently located close together, near the cell poles. However, they never shared the same position. Mutant strains of A. tumefaciens with deletions of both ppk genes (Δppk1 Δppk2) were unable to form polyphosphate but still showed cell pole-located eYFP-HppA foci and could be stained with MitoTracker. In conclusion, A. tumefaciens forms polyP granules that are free of a surrounding membrane and thus resemble polyP granules of Ralstonia eutropha and other bacteria. The composition, contents, and function of the subcellular structures that are stainable with MitoTracker and harbor eYFP-HppA remain unclear. IMPORTANCE The uptake of alphaproteobacterium-like cells by ancestors of eukaryotic cells and subsequent conversion of these alphaproteobacterium-like cells to mitochondria are thought to be key steps in the evolution of the first eukaryotic cells. The identification of acidocalcisomes in two alphaproteobacterial species some years ago and the presence of homologs of the vacuolar proton-translocating pyrophosphatase HppA, a marker protein of the acidocalcisome membrane in eukaryotes, in virtually all species within the alphaproteobacteria suggest that eukaryotic acidocalcisomes might also originate from related structures in ancestors of alphaproteobacterial species. Accordingly, alphaproteobacterial acidocalcisomes and eukaryotic acidocalcisomes should have similar features. Since hardly any information is available on bacterial acidocalcisomes, this study aimed at the characterization of organelle-like structures in alphaproteobacterial cells, with A. tumefaciens as an example.

scholarly journals Aquaponics using a fish farm effluent shifts bacterial communities profile in halophytes rhizosphere and endosphere

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Vanessa Oliveira ◽  
Patrícia Martins ◽  
Bruna Marques ◽  
Daniel F. R. Cleary ◽  
Ana I. Lillebø ◽  
...  
Keyword(s):  
Natural Environment ◽  
Bacterial Communities ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Nutrient Loads ◽  
Marine Aquaculture ◽  
Aquaculture Effluents ◽  
Specific Effects ◽  
Salicornia Ramosissima ◽  
Gradient Gel Electrophoresis ◽  
Species Specific

AbstractThe intensification of marine aquaculture raises multiple sustainability issues, namely the handling of nutrient-rich effluents that can adversely impact ecosystems. As integrated multi-trophic aquaculture (IMTA) gains momentum, the use of halophyte plants to phytoremediate aquaculture effluents has received growing attention, particularly in aquaponics. It is, therefore, important to obtain a more in-depth knowledge of the microbial communities present in the root systems of these plants, both in their natural environment (sediment) and in aquaponics, in order to understand their nutrient removal potential. The present study used denaturing gradient gel electrophoresis (DGGE) and barcoded pyrosequencing to assess the bacterial community present in the endosphere and rhizosphere of three halophyte plants: Halimione portulacoides, Salicornia ramosissima and Sarcocornia perennis. Species-specific effects were recorded in the profile and diversity of the bacterial communities present in halophyte roots, with significant differences also recorded for the same halophyte species grown in contrasting environments (sediment vs. aquaponics). In aquaponics the most abundant groups belonged to the orders Rhodocyclales, Campylobacterales, Rhodobacterales and Desulfobacterales, while in the natural environment (sediment) the most abundant groups belonged to the orders Rhizobiales, Sphingomonadales and Alteromonadales. An overall enrichment in bacterial taxa involved in nutrient cycling was recorded in the roots of halophytes grown in aquaponics (such as Denitromonas, Mesorhizobium, Colwellia, Dokdonella and Arcobacter), thereby highlighting their potential to reduce the nutrient loads from aquaculture effluents.

Model plants for studying the interaction between Methylobacterium mesophilicum and Xylella fastidiosa

2006 ◽  
Vol 52 (5) ◽  
pp. 419-426 ◽  
Author(s):  
Fernando D Andreote ◽  
Paulo T Lacava ◽  
Cláudia S Gai ◽  
Welington L Araújo ◽  
Walter Maccheroni, Jr. ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Xylella Fastidiosa ◽  
Specific Primers ◽  
Gradient Gel Electrophoresis ◽  
Polymerase Chain ◽  
Methylobacterium Mesophilicum ◽  
Biofilm Structure ◽  
Nicotiana Clevelandii

Over the last few years, endophytic bacterial communities associated with citrus have been studied as key components interacting with Xylella fastidiosa. In this study, we investigated the possible interaction between the citrus endophyte Methylobacterium mesophilicum SR1.6/6 and X. fastidiosa in model plants such as Catharanthus roseus (Madagaskar periwinkle) and Nicotiana clevelandii (Clevelands tobacco). The aim of this study was to establish the fate of M. mesophilicum SR1.6/6 after inoculation of C. roseus and N. clevelandii plants, using PCR–DGGE (polymerase chain reaction – denaturing gradient gel electrophoresis) and plating techniques. Shifts in the indigenous endophytic bacterial communities were observed in plants inoculated with strain SR1.6/6, using specific primers targeting α- and β-Proteobacteria. Cells of strain SR1.6/6 were observed in a biofilm structure on the root and hypocotyl surfaces of in vitro seedlings inoculated with M. mesophilicum SR1.6/6. This emphasizes the importance of these tissues as main points of entrance for this organism. The results showed that C. roseus and N. clevelandii could be used as model plants to study the interaction between M. mesophilicum and X. fastidiosa.Key words: endophytic, Methylobacterium, model plants, DGGE.

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