scholarly journals A Continuous Culture System for Assessing Microbial Activities in the Piezosphere

2015 ◽  
Vol 81 (19) ◽  
pp. 6850-6856 ◽  
Author(s):  
Dionysis I. Foustoukos ◽  
Ileana Pérez-Rodríguez
Keyword(s):  
Continuous Culture ◽  
Microbial Growth ◽  
Extreme Environments ◽  
Deep Biosphere ◽  
Content Type ◽  
Growth And Survival ◽  
Elevated Pressures ◽  
Physical Chemical ◽  
Fermentative Growth ◽  
Continuous Culture System

ABSTRACTContinuous culture under elevated pressures is an important technique for expanding the exploration of microbial growth and survival in extreme environments associated with the deep biosphere. Here we present a benchtop stirred continuous culture bioreactor capable of withstanding temperatures ranging from 25 to 120°C and pressures as high as 69 MPa. The system is configured to allow the employment of media enriched in dissolved gases, under oxic or anoxic conditions, while permitting periodic sampling of the incubated organisms with minimal physical/chemical disturbance inside the reactor. In a pilot experiment, the fermentative growth of the thermopiezophilic bacteriumMarinitoga piezophilawas investigated continuously for 382 h at 65°C and at pressures ranging from 0.1 to 40 MPa while the medium flow rate was varied from 2 to 0.025 ml/min. The enhanced growth observed at 30 and 40 MPa and 0.025 ml/min supports the pressure preferences ofM. piezophilawhen grown fermentatively. This assay successfully demonstrates the capabilities of the bioreactor for continuous culturing at a variety of dilution rates, pressures, and temperatures. We anticipate that this technology will accelerate our understanding of the physiological and metabolic status of microorganisms under temperature, pressure, and energy regimes resembling those of the Earth's piezosphere.

Kinetics of biodegradation of Di-n-butyl phthalate in continuous culture system

Chemosphere ◽  
1998 ◽  
Vol 37 (2) ◽  
pp. 257-264 ◽  
Author(s):  
Jianlong Wang ◽  
Ping Liu ◽  
Hanchang Shi ◽  
Yi Qian
Keyword(s):  
Continuous Culture ◽  
Culture System ◽  
Continuous Culture System ◽  
Butyl Phthalate ◽  
Kinetics Of

scholarly journals Reduction of the Temperature Sensitivity of Halomonas hydrothermalis by Iron Starvation Combined with Microaerobic Conditions

2015 ◽  
Vol 81 (6) ◽  
pp. 2156-2162 ◽  
Author(s):  
Jesse P. Harrison ◽  
John E. Hallsworth ◽  
Charles S. Cockell
Keyword(s):  
Physicochemical Parameters ◽  
Marine Bacterium ◽  
Chemical Elements ◽  
Extreme Environments ◽  
Iron Availability ◽  
Iron Starvation ◽  
Specific Chemical ◽  
Content Type ◽  
Distribution And Ecology ◽  
Microaerobic Conditions

ABSTRACTThe limits to biological processes on Earth are determined by physicochemical parameters, such as extremes of temperature and low water availability. Research into microbial extremophiles has enhanced our understanding of the biophysical boundaries which define the biosphere. However, there remains a paucity of information on the degree to which rates of microbial multiplication within extreme environments are determined by the availability of specific chemical elements. Here, we show that iron availability and the composition of the gaseous phase (aerobic versus microaerobic) determine the susceptibility of a marine bacterium,Halomonas hydrothermalis, to suboptimal and elevated temperature and salinity by impacting rates of cell division (but not viability). In particular, iron starvation combined with microaerobic conditions (5% [vol/vol] O2, 10% [vol/vol] CO2, reduced pH) reduced sensitivity to temperature across the 13°C range tested. These data demonstrate that nutrient limitation interacts with physicochemical parameters to determine biological permissiveness for extreme environments. The interplay between resource availability and stress tolerance, therefore, may shape the distribution and ecology of microorganisms within Earth's biosphere.

Litorilinea aerophila gen. nov., sp. nov., an aerobic member of the class Caldilineae , phylum Chloroflexi , isolated from an intertidal hot spring

2013 ◽  
Vol 63 (Pt_3) ◽  
pp. 1149-1154 ◽  
Author(s):  
Varsha Kale ◽  
Snædís H. Björnsdóttir ◽  
Ólafur H. Friðjónsson ◽  
Sólveig K. Pétursdóttir ◽  
Sesselja Ómarsdóttir ◽  
...  
Keyword(s):  
Type Species ◽  
Hot Spring ◽  
Sequence Similarity ◽  
Rrna Gene ◽  
Content Type ◽  
Phenotypic Differences ◽  
Link Type ◽  
Fermentative Growth ◽  
Distinct Lineage ◽  
Ph Range

A thermophilic, aerobic, Gram-stain-negative, filamentous bacterium, strain PRI-4131T, was isolated from an intertidal hot spring in Isafjardardjup, NW Iceland. The strain grew chemo-organotrophically on various carbohydrates. The temperature range for growth was 40–65 °C (optimum 55 °C), the pH range was pH 6.5–9.0 (optimum pH 7.0) and the NaCl range was 0–3 % (w/v) (optimum 0.5 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain PRI-4131T represented a distinct lineage within the class Caldilineae of the phylum Chloroflexi. The highest levels of sequence similarity, about 91 %, were with Caldilinea aerophila STL-6-O1T and Caldilinea tarbellica D1-25-10-4T. Fermentative growth was not observed for strain PRI-4131T, which, in addition to other characteristics, distinguished it from the two Caldilinea species. Owing to both phylogenetic and phenotypic differences from the described members of the class Caldilineae , we propose to accommodate strain PRI-4131T in a novel species in a new genus, Litorilinea aerophila gen. nov., sp. nov. The type strain of Litorilinea aerophila is PRI-4131T ( = DSM 25763T  = ATCC BAA-2444T).

scholarly journals Trk2 Potassium Transport System in Streptococcus mutans and Its Role in Potassium Homeostasis, Biofilm Formation, and Stress Tolerance

2016 ◽  
Vol 198 (7) ◽  
pp. 1087-1100 ◽  
Author(s):  
Gursonika Binepal ◽  
Kamal Gill ◽  
Paula Crowley ◽  
Martha Cordova ◽  
L. Jeannine Brady ◽  
...  
Keyword(s):  
Stress Tolerance ◽  
Streptococcus Mutans ◽  
Transport System ◽  
Biofilm Formation ◽  
Cellular Response ◽  
Pathogenic Bacteria ◽  
Transport Systems ◽  
Content Type ◽  
Growth And Survival ◽  
Dental Biofilm

ABSTRACTPotassium (K+) is the most abundant cation in the fluids of dental biofilm. The biochemical and biophysical functions of K+and a variety of K+transport systems have been studied for most pathogenic bacteria but not for oral pathogens. In this study, we establish the modes of K+acquisition inStreptococcus mutansand the importance of K+homeostasis for its virulence attributes. TheS. mutansgenome harbors four putative K+transport systems that included two Trk-like transporters (designated Trk1 and Trk2), one glutamate/K+cotransporter (GlnQHMP), and a channel-like K+transport system (Kch). Mutants lacking Trk2 had significantly impaired growth, acidogenicity, aciduricity, and biofilm formation. [K+] less than 5 mM eliminated biofilm formation inS. mutans. The functionality of the Trk2 system was confirmed by complementing anEscherichia coliTK2420 mutant strain, which resulted in significant K+accumulation, improved growth, and survival under stress. Taken together, these results suggest that Trk2 is the main facet of the K+-dependent cellular response ofS. mutansto environment stresses.IMPORTANCEBiofilm formation and stress tolerance are important virulence properties of caries-causingStreptococcus mutans. To limit these properties of this bacterium, it is imperative to understand its survival mechanisms. Potassium is the most abundant cation in dental plaque, the natural environment ofS. mutans. K+is known to function in stress tolerance, and bacteria have specialized mechanisms for its uptake. However, there are no reports to identify or characterize specific K+transporters inS. mutans. We identified the most important system for K+homeostasis and its role in the biofilm formation, stress tolerance, and growth. We also show the requirement of environmental K+for the activity of biofilm-forming enzymes, which explains why such high levels of K+would favor biofilm formation.

Three-stage continuous culture system with a self-generated anaerobia to study the regionalized metabolism of the human gut microbiota

2014 ◽  
Vol 96 ◽  
pp. 111-118 ◽  
Author(s):  
David Feria-Gervasio ◽  
William Tottey ◽  
Nadia Gaci ◽  
Monique Alric ◽  
Jean-Michel Cardot ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Continuous Culture ◽  
Culture System ◽  
Human Gut ◽  
Human Gut Microbiota ◽  
Continuous Culture System

scholarly journals Effects of lipopolysaccharide dosing on bacterial community composition and fermentation in a dual-flow continuous culture system

2019 ◽  
Vol 102 (1) ◽  
pp. 334-350 ◽  
Author(s):  
X. Dai ◽  
E.M. Paula ◽  
A.L.J. Lelis ◽  
L.G. Silva ◽  
V.L.N. Brandao ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Continuous Culture ◽  
Community Composition ◽  
Culture System ◽  
Bacterial Community Composition ◽  
Continuous Culture System

scholarly journals Lactobacillus fructivorans Spoilage of Tomato Ketchup

1997 ◽  
Vol 60 (5) ◽  
pp. 505-509 ◽  
Author(s):  
K. JOHANNA BJORKROTH ◽  
HANNU J. KORKEALA
Keyword(s):  
Gel Electrophoresis ◽  
Microbial Growth ◽  
Antimicrobial Agents ◽  
Growth And Survival ◽  
Factors Affecting ◽  
Physiological And Biochemical Characteristics ◽  
Gas Formation ◽  
Tomato Ketchup ◽  
Dna Fragment ◽  
Physiological And Biochemical

Spoilage characterized by bulging as a result of gas formation in bottled ketchup was studied, Samples produced microbial growth on MRS and Rogosa selective Lactobacillus agar. Seventy randomly selected isolates typed by using restriction endonuclease (ClaI, EcoRI, HindIII) analysis were found to have identical DNA fragment patterns in gel electrophoresis. The strain was identified as Lactobacillus fructivorans using morphological, physiological and biochemical characteristics, combined with the information obtained from ribotyping. Factors affecting growth and survival of this L. fructivorans strain in ketchup production were also studied. An L. fructivorans count of 105 CFU/g resulted in spoilage of inoculated ketchup samples. Spoilage occurred only in samples incubated at 15 to 30°C. The L. fructivorans implicated in causing spoilage demonstrated heat resistance with a D value of 1.2 min at 65°C. The strain did not show resistance to alkaline active chloride-containing detergent sanitizer; alkyldimethylbenzylammonium chloride and alkyldimethylethylbenzylammonium chloride-containing sanitizer were also found to be effective antimicrobial agents.

scholarly journals Genomic and metagenomic surveys of hydrogenase distribution indicate H2 is a widely utilised energy source for microbial growth and survival

2015 ◽  
Vol 10 (3) ◽  
pp. 761-777 ◽  
Author(s):  
Chris Greening ◽  
Ambarish Biswas ◽  
Carlo R Carere ◽  
Colin J Jackson ◽  
Matthew C Taylor ◽  
...  
Keyword(s):  
Energy Source ◽  
Microbial Growth ◽  
Growth And Survival

scholarly journals Design and development of a continuous culture system for studying rumen fermentation

1989 ◽  
Vol 61 (5) ◽  
pp. 463-473
Author(s):  
Harri Miettinen ◽  
Jouko Setälä
Keyword(s):  
Continuous Culture ◽  
Culture System ◽  
Artificial Saliva ◽  
Present Report ◽  
Ammonia Concentration ◽  
Rumen Fermentation ◽  
Liquid Volume ◽  
Desktop Computer ◽  
Continuous Culture System

The present report describes an in vitro continuous culture system to simulate rumen fermentation. The complete assembly consists of six culture vessels (liquid volume 700 ml) fed twice daily with finely ground feed. The artificial saliva enters the vessel continuously, and the effluent leaves it continuously through the overflow port. The intermittent stirring of the fermentor content and the pH regulation are automatically controlled by a desktop computer. Two replicate experiments with ten fermentors given a diet of silage (50 %) and barley (50 %) were made in order to evaluate the system. The results indicate that the system reaches steady-state conditions within three to five days, ammonia concentration being an exeption. It takes for the ammonia concentration approximately 11—14 days to stabilize. The plateau values for the total volatile fatty acid (VFA) concentrations, the molar proportions of individual VFAs, and the ammonia concentrations were found to be within the accepted range in the rumen of animals given similar diets or in other artificial rumen systems. There was a tenfold decrease in the numbers of protozoa in the fermentors during the first four days of incubation. However, the average plateau value for the protozoa numbers (2.5 x 104/ml) is in the same range as in the dual flow continuous culture systems. The efficiency of the microbial N production was higher than that usually observed in vivo or in vitro (45 vs. 30 g/kg organic matter digested). The results indicate that this continuous culture system provides a reasonable estimate of rumen fermentation.

293 Nutritional evaluation of forage ephedra (Ephedra nevadensis) as an alternative forage using a dual-flow continuous culture system

2017 ◽  
Vol 95 (suppl_4) ◽  
pp. 145-145
Author(s):  
C. B. Sampaio ◽  
E. Marostegan de Paula ◽  
L. Galoro da Silva ◽  
V. Brandao ◽  
X. Dai ◽  
...  
Keyword(s):  
Continuous Culture ◽  
Culture System ◽  
Nutritional Evaluation ◽  
Continuous Culture System ◽  
Ephedra Nevadensis
Sign in / Sign up

Export Citation Format

Share Document