Application of flow cytometry for examining phytoplankton succession in two eutrophic lakes

Flow cytometry has potential as a rapid assessment technique to evaluate phytoplankton biomass and species composition. It facilitates for multi-parameter analysis of individual cells on the basis of light scattering effects induced from cellular constituents, as well as auto-fluorescence. Fluorescence emission characteristics may be especially useful in classifying cyanobacteria as they contain phycoerythrin which emits light predominantly in the 550–600 nm waveband, chlorophyll-a (650–700 nm emission) and allophycocyanin (660 nm emission). The objective of our study was to assess the utility of flow cytometry for the rapid identification and sorting of freshwater algae and cyanobacteria species. Using a selection of laboratory-cultured freshwater algae and cyanobacteria species, this study demonstrated unique light scatter and fluorescent characteristics for each species examined, allowing for rapid species identification and sorting of mixed populations of laboratory cultures and samples from two lakes in the Rotorua region (New Zealand). Analysis of lake water samples collected over seven months demonstrated changes in abundance and community composition of phytoplankton in the two lakes and demonstrates that flow cytometry may be a useful technique for examining seasonal changes in phytoplankton composition.

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A new fluorescent probe for the equilibrative inhibitor-sensitive nucleoside transporter. 5′-S-(2-aminoethyl)-N6-(4-nitrobenzyl)-5′-thioadenosine (SAENTA)-x2-fluorescein

Biochemical Journal ◽

10.1042/bj2730667 ◽

1991 ◽

Vol 273 (3) ◽

pp. 667-672 ◽

Cited By ~ 16

Author(s):

J S Wiley ◽

A M Brocklebank ◽

M B Snook ◽

G P Jamieson ◽

W H Sawyer ◽

...

Keyword(s):

Flow Cytometry ◽

Mammalian Cells ◽

Total Concentration ◽

Rapid Assessment ◽

Tight Binding ◽

Fluorescein Isothiocyanate ◽

Molar Ratio ◽

Nucleoside Transporter ◽

Affinity Ligand ◽

Leukaemic Cells

The N6-(4-nitrobenzyl) derivative of adenosine is a tight-binding inhibitor of the equilibrative inhibitor-sensitive nucleoside transporter of mammalian cells. A fluorescent ligand for this transporter has been synthesized by allowing an adenosine analogue. 5′-S-(2-aminoethyl)-N6-(4-nitrobenzyl)-5′-thioadenosine (SAENTA), to react with fluorescein isothiocyanate. The purified adduct had a SAENTA/fluorescein molar ratio of 0.92:1 calculated from its absorption spectrum. The intensity of fluorescent emission from the SAENTA-chi 2-fluorescein adduct was 30% that of fluorescein isothiocyanate (chi 2 is the number of atoms in the linkage between fluorescein and SAENTA). SAENTA-chi 2-fluorescein inhibited the influx of nucleosides into cultured leukaemic cells with an IC50 (total concentration of inhibitor producing 50% inhibition) of 40 nM. The adduct inhibited the binding of [3H]nitrobenzylthioinosine ([3H]NBMPR) with half-maximal inhibition at 50-100 nM. Mass Law analysis of the competitive-binding data suggested the presence of two classes of sites for [3H]NBMPR binding, only one of which was accessible to SAENTA-chi 2-fluorescein. Flow cytometry was used to analyse equilibrium binding of SAENTA-chi 2-fluorescein to leukaemic cells and a Kd of 6 nM was obtained. SAENTA-chi 2-fluorescein is a high-affinity ligand for the equilibrative inhibitor-sensitive nucleoside transporter which allows rapid assessment of transport capacity by flow cytometry.

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Gas Turbine Combustor Design Parameter Analysis for Soot Reduction Using CFD

Volume 2: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/99-gt-240 ◽

1999 ◽

Cited By ~ 1

Author(s):

D. Scott Crocker ◽

Rahul Puri

Keyword(s):

Software Package ◽

Negative Impact ◽

Experimental Testing ◽

Stability Margin ◽

Primary Objective ◽

Parameter Analysis ◽

Cfd Modeling ◽

Gas Turbine Combustor ◽

Primary Zone ◽

Selection Of

AlliedSignal’s F124 combustor is analyzed using CFD as part of an effort to improve the design of the combustor. A reduction of soot emissions, without negative impact on other performance features such as liner life and lean stability, was the primary objective. The existing F124 combustor (TFE1042) was modeled using the commercial CFD-ACE+ software package to validate the CFD results and provide a basis for comparison for the modified design. Two design of experiment (DOE) matrices of the redesigned combustor were analyzed using CFD modeling. The results of the CFD solutions led to the selection of two configurations for combustor rig experimental testing. The test configurations were selected based on CFD predicted trends for smoke, ignition, lean stability and pattern factor. Engine tests demonstrated a smoke number reduction from more than 40 to less than 10. Lean stability was degraded as a result of a leaner primary zone, but adequate lean stability margin was maintained.

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Rapid Identification of Staphylococcus aureus in Blood Cultures by a Combination of Fluorescence In Situ Hybridization Using Peptide Nucleic Acid Probes and Flow Cytometry

Journal of Clinical Microbiology ◽

10.1128/jcm.43.9.4855-4857.2005 ◽

2005 ◽

Vol 43 (9) ◽

pp. 4855-4857 ◽

Cited By ~ 42

Author(s):

H. Hartmann ◽

H. Stender ◽

A. Schafer ◽

I. B. Autenrieth ◽

V. A. J. Kempf

Keyword(s):

Staphylococcus Aureus ◽

Flow Cytometry ◽

In Situ Hybridization ◽

Nucleic Acid ◽

Fluorescence In Situ Hybridization ◽

Peptide Nucleic Acid ◽

Rapid Identification ◽

Blood Cultures ◽

Nucleic Acid Probes

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Flow cytometry for rapid assessment of viability after exposure to a quaternary ammonium compound

Journal of Applied Microbiology ◽

10.1111/j.1365-2672.1996.tb01934.x ◽

1996 ◽

Vol 81 (4) ◽

pp. 411-418 ◽

Cited By ~ 4

Author(s):

S. Langsrud ◽

G. Sundheim

Keyword(s):

Flow Cytometry ◽

Quaternary Ammonium ◽

Rapid Assessment ◽

Quaternary Ammonium Compound ◽

Ammonium Compound

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Multimodal Approach to Assessment of Fecal Microbiota Donors based on Three Complementary Methods

Journal of Clinical Medicine ◽

10.3390/jcm9072036 ◽

2020 ◽

Vol 9 (7) ◽

pp. 2036

Author(s):

Jaroslaw Bilinski ◽

Mikolaj Dziurzynski ◽

Pawel Grzesiowski ◽

Edyta Podsiadly ◽

Anna Stelmaszczyk-Emmel ◽

...

Keyword(s):

Flow Cytometry ◽

Fecal Microbiota ◽

Dead Cell ◽

Series Of Experiments ◽

Multi Method Approach ◽

The Stability ◽

Next Generation Sequencing Ngs ◽

Ngs Data ◽

Generation Sequencing ◽

Selection Of

Methods of stool assessment are mostly focused on next-generation sequencing (NGS) or classical culturing, but only rarely both. We conducted a series of experiments using a multi-method approach to trace the stability of gut microbiota in various donors over time, to find the best method for the proper selection of fecal donors and to find “super-donor” indicators. Ten consecutive stools donated by each of three donors were used for the experiments (30 stools in total). The experiments assessed bacterial viability measured by flow cytometry, stool culturing on different media and in various conditions, and NGS (90 samples in total). There were no statistically significant differences between live and dead cell numbers; however, we found a group of cells classified as not-dead-not-alive, which may be possibly important in selection of “good” donors. Donor C, being a regular stool donor, was characterized by the largest number of cultivable species (64). Cultivable core microbiota (shared by all donors) was composed of only 16 species. ANCOM analysis of NGS data highlighted particular genera to be more abundant in one donor vs. the others. There was a correlation between the not-dead-not-alive group found in flow cytometry and Anaeroplasma found by NGS, and we could distinguish a regular stool donor from the others. In this work, we showed that combining various methods of microbiota assessment gives more information than each method separately.

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Changes of viral and prokaryote abundances in a high rate algal pond using flow cytometry detection

Water Science & Technology ◽

10.2166/wst.2020.379 ◽

2020 ◽

Vol 82 (6) ◽

pp. 1062-1069

Author(s):

Ashleigh R. Hisee ◽

Matthew Hisee ◽

Jody C. McKerral ◽

Stephanie R. Rosenbauer ◽

James S. Paterson ◽

...

Keyword(s):

Flow Cytometry ◽

South Australia ◽

Rapid Identification ◽

Microbial Interactions ◽

High Rate ◽

Treated Wastewater ◽

Bacterial Populations ◽

Flow Cytometry Detection ◽

Wastewater Samples ◽

Mixed Systems

Abstract High rate algal ponds (HRAPs) are shallow, mixed systems for wastewater treatment, which use sunlight exposure for disinfection. Little is known regarding the relationships between the bacteria and viruses within HRAP systems. Uniquely, flow cytometry permits the rapid identification of bacterial and viral populations in wastewater samples, separating populations based on genome and particle size. Treated wastewater samples were collected from an HRAP at Kingston on Murray, South Australia. Flow cytometry analysis detected bacterial populations and discriminated virus-like particles (VLP) and large VLP (LVLP). Rapid, short term, fluctuations in the abundance of all three populations were observed. Changes in the abundance of these populations was compared; wastewater composition was used as metadata for the comparisons. Linear regression determined relationships in abundances between bacteria and LVLP (R2 0.2985); LVLP and VLP (R2 0.5829) and bacteria and VLP (R2 0.5778) all with p-values of <0.001. Bacterial, LVLP and VLP abundance positively correlated with each other, indicating potential microbial interactions. Overall, the results suggest a parasitic relationship was occurring and driving the abundances of bacteria and viruses within the system.

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