Karen Daly

Dr. Karen Daly

Department of Crops, Environment & Land Use, The Agriculture and Food Development Authority, TEAGASC, Johnstown Castle, Wexford, Ireland
orcid

Research Focus & Metrics

Academic Career Length

26Years (2001-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 April 2018 in Microbiome
Verified
Journal Article
Open access
PDF file
ASAndrey N Shkoporov
Andrey N Shkoporov
FRFeargal Ryan
Feargal Ryan
LDLorraine Draper
Lorraine Draper
AFAmanda Forde
Amanda Forde
SSStephen Stockdale
Stephen Stockdale
CHColin Hill
Colin Hill
Recent studies have demonstrated that the human gut is populated by complex, highly individual and stable communities of viruses, the majority of which are bacteriophages. While disease-specific alterations in the gut phageome have been observed in IBD, AIDS and acute malnutrition, the human gut phageome remains poorly characterised. One important obstacle in metagenomic studies of the human gut phageome is a high level of discrepancy between results obtained by different research groups. This is often due to the use of different protocols for enriching virus-like particles, nucleic acid purification and sequencing. The goal of the present study is to develop a relatively simple, reproducible and cost-efficient protocol for the extraction of viral nucleic acids from human faecal samples, suitable for high-throughput studies. We also analyse the effect of certain potential confounding factors, such as storage conditions, repeated freeze-thaw cycles, and operator bias on the resultant phageome profile. Additionally, spiking of faecal samples with an exogenous phage standard was employed to quantitatively analyse phageomes following metagenomic sequencing. Comparative analysis of phageome profiles to bacteriome profiles was also performed following 16S rRNA amplicon sequencing. Faecal phageome profiles exhibit an overall greater individual specificity when compared to bacteriome profiles. The phageome and bacteriome both exhibited moderate change when stored at + 4 °C or room temperature. Phageome profiles were less impacted by multiple freeze-thaw cycles than bacteriome profiles, but there was a greater chance for operator effect in phageome processing. The successful spiking of faecal samples with exogenous bacteriophage demonstrated large variations in the total viral load between individual samples. The faecal phageome sequencing protocol developed in this study provides a valuable additional view of the human gut microbiota that is complementary to 16S amplicon sequencing and/or metagenomic sequencing of total faecal DNA. The protocol was optimised for several confounding factors that are encountered while processing faecal samples, to reduce discrepancies observed within and between research groups studying the human gut phageome. Rapid storage, limited freeze-thaw cycling and spiking of faecal samples with an exogenous phage standard are recommended for optimum results.

1 October 2018 in Journal of Environmental Management
Verified
Journal Article
Closed access
ADAmar Daxini
Amar Daxini
COCathal O'DOnoghue
Cathal O'DOnoghue
MRMary Ryan
Mary Ryan
CBCathal Buckley
Cathal Buckley
ABAndrew Barnes
Andrew Barnes
KDKaren Daly
Karen Daly

27 May 2015 in European Journal of Soil Science
Verified
Journal Article
Closed access
PDF file
KDKaren Daly
Karen Daly
DSD. Styles
D. Styles
SLS. Lalor
S. Lalor
DWD. P. Wall
D. P. Wall

1 March 2001 in Soil Use and Management
Verified
Journal Article
Closed access
PDF file
KDKaren Daly
Karen Daly
DJD. Jeffrey
D. Jeffrey
HTH. Tunney
H. Tunney

1 September 2021 in Journal of Cleaner Production
Verified
Journal Article
Open access
WSW. Shi
W. Shi
MHM.G. Healy
M.G. Healy
SAS.M. Ashekuzzaman
S.M. Ashekuzzaman
KDKaren Daly
Karen Daly
JLJ.J. Leahy
J.J. Leahy
OFO. Fenton
O. Fenton

1 March 2005 in Journal of Hydrology
Verified
Journal Article
Closed access
PJPhilip Jordan
Philip Jordan
WMWayne Menary
Wayne Menary
KDKaren Daly
Karen Daly
GKGerard Kiely
Gerard Kiely
GMGerard Morgan
Gerard Morgan
RMRichard Moles
Richard Moles