Limits...
In-Field Implementation of a Recombinant Factor C Assay for the Detection of Lipopolysaccharide as a Biomarker of Extant Life within Glacial Environments.

Barnett MJ, Wadham JL, Jackson M, Cullen DC - Biosensors (Basel) (2012)

Bottom Line: In situ or in-field detection and characterisation of microbial communities is becoming recognised as an important approach to improve our understanding of such communities.Within this context we demonstrate, for the first time, the ability to detect Gram-negative bacteria in glacial field-environments (including subglacial environments) via the detection of lipopolysaccharide (LPS); an important component of Gram-negative bacterial cell walls.Sixteen of these samples returned positive LPS detection.

View Article: PubMed Central - PubMed

Affiliation: Cranfield Health, Vincent Building, Cranfield University, Cranfield, Bedfordshire, MK43 0AL, UK. m.barnett.s06@gmail.com.

ABSTRACT
The discovery over the past two decades of viable microbial communities within glaciers has promoted interest in the role of glaciers and ice sheets (the cryosphere) as contributors to subglacial erosion, global biodiversity, and in regulating global biogeochemical cycles. In situ or in-field detection and characterisation of microbial communities is becoming recognised as an important approach to improve our understanding of such communities. Within this context we demonstrate, for the first time, the ability to detect Gram-negative bacteria in glacial field-environments (including subglacial environments) via the detection of lipopolysaccharide (LPS); an important component of Gram-negative bacterial cell walls. In-field measurements were performed using the recently commercialised PyroGene® recombinant Factor C (rFC) endotoxin detection system and used in conjunction with a handheld fluorometer to measure the fluorescent endpoint of the assay. Twenty-seven glacial samples were collected from the surface, bed and terminus of a low-biomass Arctic valley glacier (Engabreen, Northern Norway), and were analysed in a field laboratory using the rFC assay. Sixteen of these samples returned positive LPS detection. This work demonstrates that LPS detection via rFC assay is a viable in-field method and is expected to be a useful proxy for microbial cell concentrations in low biomass environments.

No MeSH data available.


Related in: MedlinePlus

Determination of LPS levels in 27 glacial samples using the rFC assay. Details of the sampling sites are described in Section 2.3. All assays were performed with no significant sample processing (minimal processing protocol). LPS concentration was quantified by using the daily LPS calibration sets, assuming a linear interpolation from a log-log plot of LPS standards (10, 1 and 0.1 EU·ml−1) and the assay responses. The y-axis (LPS concentration) has been truncated (i.e., the value for 2009 englacial water is clipped) to enable better visualisation of the relationship of the LPS concentration values of the other samples. Error bars are ±1 SD of assay responses from triplicates.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4263545&req=5

f4-biosensors-02-00083: Determination of LPS levels in 27 glacial samples using the rFC assay. Details of the sampling sites are described in Section 2.3. All assays were performed with no significant sample processing (minimal processing protocol). LPS concentration was quantified by using the daily LPS calibration sets, assuming a linear interpolation from a log-log plot of LPS standards (10, 1 and 0.1 EU·ml−1) and the assay responses. The y-axis (LPS concentration) has been truncated (i.e., the value for 2009 englacial water is clipped) to enable better visualisation of the relationship of the LPS concentration values of the other samples. Error bars are ±1 SD of assay responses from triplicates.

Mentions: To demonstrate that the rFC assay could detect LPS in a variety of glacial samples in the field, 27 samples from various subglacial and subaerial locations (locations described in Section 2.3) were tested for the presence of LPS. Figure 4 shows LPS concentrations measured in the samples assayed.


In-Field Implementation of a Recombinant Factor C Assay for the Detection of Lipopolysaccharide as a Biomarker of Extant Life within Glacial Environments.

Barnett MJ, Wadham JL, Jackson M, Cullen DC - Biosensors (Basel) (2012)

Determination of LPS levels in 27 glacial samples using the rFC assay. Details of the sampling sites are described in Section 2.3. All assays were performed with no significant sample processing (minimal processing protocol). LPS concentration was quantified by using the daily LPS calibration sets, assuming a linear interpolation from a log-log plot of LPS standards (10, 1 and 0.1 EU·ml−1) and the assay responses. The y-axis (LPS concentration) has been truncated (i.e., the value for 2009 englacial water is clipped) to enable better visualisation of the relationship of the LPS concentration values of the other samples. Error bars are ±1 SD of assay responses from triplicates.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4263545&req=5

f4-biosensors-02-00083: Determination of LPS levels in 27 glacial samples using the rFC assay. Details of the sampling sites are described in Section 2.3. All assays were performed with no significant sample processing (minimal processing protocol). LPS concentration was quantified by using the daily LPS calibration sets, assuming a linear interpolation from a log-log plot of LPS standards (10, 1 and 0.1 EU·ml−1) and the assay responses. The y-axis (LPS concentration) has been truncated (i.e., the value for 2009 englacial water is clipped) to enable better visualisation of the relationship of the LPS concentration values of the other samples. Error bars are ±1 SD of assay responses from triplicates.
Mentions: To demonstrate that the rFC assay could detect LPS in a variety of glacial samples in the field, 27 samples from various subglacial and subaerial locations (locations described in Section 2.3) were tested for the presence of LPS. Figure 4 shows LPS concentrations measured in the samples assayed.

Bottom Line: In situ or in-field detection and characterisation of microbial communities is becoming recognised as an important approach to improve our understanding of such communities.Within this context we demonstrate, for the first time, the ability to detect Gram-negative bacteria in glacial field-environments (including subglacial environments) via the detection of lipopolysaccharide (LPS); an important component of Gram-negative bacterial cell walls.Sixteen of these samples returned positive LPS detection.

View Article: PubMed Central - PubMed

Affiliation: Cranfield Health, Vincent Building, Cranfield University, Cranfield, Bedfordshire, MK43 0AL, UK. m.barnett.s06@gmail.com.

ABSTRACT
The discovery over the past two decades of viable microbial communities within glaciers has promoted interest in the role of glaciers and ice sheets (the cryosphere) as contributors to subglacial erosion, global biodiversity, and in regulating global biogeochemical cycles. In situ or in-field detection and characterisation of microbial communities is becoming recognised as an important approach to improve our understanding of such communities. Within this context we demonstrate, for the first time, the ability to detect Gram-negative bacteria in glacial field-environments (including subglacial environments) via the detection of lipopolysaccharide (LPS); an important component of Gram-negative bacterial cell walls. In-field measurements were performed using the recently commercialised PyroGene® recombinant Factor C (rFC) endotoxin detection system and used in conjunction with a handheld fluorometer to measure the fluorescent endpoint of the assay. Twenty-seven glacial samples were collected from the surface, bed and terminus of a low-biomass Arctic valley glacier (Engabreen, Northern Norway), and were analysed in a field laboratory using the rFC assay. Sixteen of these samples returned positive LPS detection. This work demonstrates that LPS detection via rFC assay is a viable in-field method and is expected to be a useful proxy for microbial cell concentrations in low biomass environments.

No MeSH data available.


Related in: MedlinePlus