Gregory R OBrian

Works (10)

Updated: April 25th, 2025 18:25

2020 article

Aspergillus flavus Exploits Maize Kernels Using an “Orphan” Secondary Metabolite Cluster

Antiga, L., Starza, S. R. L., Miccoli, C., Simone, D. A., Scala, V., Zaccaria, M., … Reverberi, M. (2020, November 3). International Journal of Molecular Sciences.

By: L. Antiga*, S. Starza*, C. Miccoli, D. Simone *, V. Scala, M. Zaccaria *, X. Shu *, G. Obrian n ...

author keywords: Aspergillus flavus; maize kernel; salicylate hydroxylase; npp1; effectors; quercetin; histology
MeSH headings : Aflatoxins / genetics; Aflatoxins / metabolism; Aspergillosis / genetics; Aspergillosis / metabolism; Aspergillus flavus / genetics; Aspergillus flavus / pathogenicity; Aspergillus flavus / physiology; Catechols / metabolism; Crops, Agricultural / genetics; Crops, Agricultural / metabolism; Crops, Agricultural / microbiology; Disease Resistance / genetics; Gene Expression Regulation, Plant; Metabolic Networks and Pathways / genetics; Mixed Function Oxygenases / genetics; Mixed Function Oxygenases / metabolism; Multigene Family; Organisms, Genetically Modified; Plant Diseases / genetics; Plant Diseases / microbiology; Quercetin / metabolism; Salicylic Acid / metabolism; Seeds; Zea mays / genetics; Zea mays / metabolism; Zea mays / microbiology
topics (OpenAlex): Mycotoxins in Agriculture and Food; Fungal and yeast genetics research; Plant Disease Resistance and Genetics
TL;DR: Results suggest that the initial phase of fungal infection of the living tissues of maize kernels coincides with a significant increase ofFungal effectors such as SalOH and Npp1 that appear to be instrumental in eluding host defences and colonising the starch-enriched tissues, and therefore suggest a role of cluster 32 to the onset of infection. (via Semantic Scholar)
Source: Web Of Science
Added: November 30, 2020

2017 article

Carbon Dioxide Mediates the Response to Temperature and Water Activity Levels in Aspergillus flavus during Infection of Maize Kernels

Gilbert, M., Medina, A., Mack, B., Lebar, M., Rodríguez, A., Bhatnagar, D., … Payne, G. (2017, December 22). Toxins.

By: M. Gilbert *, A. Medina *, B. Mack *, M. Lebar *, A. Rodríguez *, D. Bhatnagar*, N. Magan *, G. Obrian n, G. Payne n

author keywords: aflatoxin; Zea mays; climate change; secondary metabolites; RNA-seq
MeSH headings : Aflatoxin B1 / metabolism; Aspergillus flavus / genetics; Aspergillus flavus / metabolism; Carbon Dioxide; Edible Grain / microbiology; Plant Diseases; Temperature; Transcriptome; Water; Zea mays / microbiology
topics (OpenAlex): Mycotoxins in Agriculture and Food; Meat and Animal Product Quality; Indoor Air Quality and Microbial Exposure
TL;DR: RNA sequencing data indicated that several genes, and in particular those involved in the biosynthesis of secondary metabolites, exhibit different responses to water availability or temperature stress depending on the atmospheric CO2 content, and two gene networks significantly influenced by changes in CO2 levels were identified. (via Semantic Scholar)
UN Sustainable Development Goals Color Wheel
UN Sustainable Development Goal Categories
6. Clean Water and Sanitation (OpenAlex)
Source: Web Of Science
Added: August 6, 2018

2013 article

Localization, morphology and transcriptional profile of A spergillus flavus during seed colonization

Dolezal, A. L., Obrian, G. R., Nielsen, D. M., Woloshuk, C. P., Boston, R. S., & Payne, G. A. (2013, July 8). Molecular Plant Pathology, Vol. 14, pp. 898–909.

By: A. Dolezal n, G. Obrian n, D. Nielsen n , C. Woloshuk *, R. Boston n & G. Payne n

MeSH headings : Aspergillus flavus / genetics; Aspergillus flavus / growth & development; Aspergillus flavus / pathogenicity; Chromosomes, Fungal / genetics; Colony Count, Microbial; DNA, Fungal / isolation & purification; Electrophoresis, Agar Gel; Endosperm / microbiology; Gene Expression Profiling; Gene Expression Regulation, Fungal; Genes, Fungal / genetics; Humans; Seeds / cytology; Seeds / microbiology; Transcription Factors / metabolism; Transcription, Genetic; Zea mays / cytology; Zea mays / microbiology
topics (OpenAlex): Mycotoxins in Agriculture and Food; Plant-Microbe Interactions and Immunity; Fungal and yeast genetics research
TL;DR: Results from these studies indicate that A. flavus is capable of infecting all tissues of the immature kernel by 96 h after infection and will aid in the development of strategies aimed at preventing or slowing down A. flavus colonization of the maize kernel. (via Semantic Scholar)
UN Sustainable Development Goals Color Wheel
UN Sustainable Development Goal Categories
2. Zero Hunger (OpenAlex)
Sources: Web Of Science, NC State University Libraries
Added: August 6, 2018

2008 article

Quantification of Urinary Aflatoxin B1 Dialdehyde Metabolites Formed by Aflatoxin Aldehyde Reductase Using Isotope Dilution Tandem Mass Spectrometry

Johnson, D. N., Egner, P. A., OBrian, G., Glassbrook, N., Roebuck, B. D., Sutter, T. R., … Groopman, J. D. (2008, February 12). Chemical Research in Toxicology.

By: D. Johnson n, P. Egner n, G. OBrian n, N. Glassbrook n, B. Roebuck n, T. Sutter  n, G. Payne n, T. Kensler  n, J. Groopman  n

MeSH headings : Aflatoxin B1 / urine; Aldehyde Reductase / metabolism; Aldehydes / metabolism; Animals; Carcinogens / metabolism; Chromatography, Affinity; Chromatography, High Pressure Liquid; Diet; Escherichia coli / metabolism; Glucuronidase / urine; Male; Radioisotope Dilution Technique; Rats; Rats, Sprague-Dawley; Reference Standards; Solid Phase Extraction; Spectrometry, Mass, Electrospray Ionization; Sulfatases / urine
topics (OpenAlex): Genomics, phytochemicals, and oxidative stress; Bee Products Chemical Analysis; Sunflower and Safflower Cultivation
TL;DR: This highly sensitive and specific isotope dilution method is applicable to in vivo quantification of urinary alcohol products produced by AFAR and contributes to the goal of mass balancing the fate of the bioreactive 8,9-epoxides of AFB 1 in vivo. (via Semantic Scholar)
Source: Web Of Science
Added: August 6, 2018

2007 journal article

Elucidation of veA-dependent genes associated with aflatoxin and sclerotial production in Aspergillus flavus by functional genomics

Applied Microbiology and Biotechnology, 76(5), 1107–1118.

By: J. Cary *, G. OBrian n, D. Nielsen n , W. Nierman *, P. Harris-Coward*, J. Yu*, D. Bhatnagar*, T. Cleveland *, G. Payne n, A. Calvo *

author keywords: Aspergillus flavus; veA; aflatoxin; sclerotia; microarray
MeSH headings : Aflatoxins / biosynthesis; Anthraquinones / metabolism; Aspergillus flavus / genetics; Aspergillus flavus / growth & development; Aspergillus flavus / metabolism; Fungal Proteins / genetics; Fungal Proteins / metabolism; Gene Expression Profiling; Gene Expression Regulation, Fungal; Gene Library; Genomics; Oligonucleotide Array Sequence Analysis / methods
topics (OpenAlex): Mycotoxins in Agriculture and Food; Fungal and yeast genetics research; Plant Disease Resistance and Genetics
TL;DR: Microarray technology was used to identify a subgroup of veA-dependent genes that exhibited time-dependent expression profiles similar to those of known aflatoxin biosynthetic genes or that were candidates for involvement in sclerotial production in the wild type. (via Semantic Scholar)
Sources: Web Of Science, Crossref, NC State University Libraries
Added: August 6, 2018

2007 article

Function and regulation ofaflJin the accumulation of aflatoxin early pathway intermediate inAspergillus flavus

Du, W., Obrian, G. R., & Payne, G. A. (2007, September 23). Food Additives & Contaminants.

By: W. Du n, G. Obrian n & G. Payne n

author keywords: aflatoxin; regulation
MeSH headings : Aflatoxins / biosynthesis; Aflatoxins / genetics; Aspergillus flavus / genetics; Aspergillus flavus / metabolism; Fungal Proteins / genetics; Fungal Proteins / metabolism; Gene Expression Regulation, Fungal; Genes, Fungal; Polymerase Chain Reaction / methods
topics (OpenAlex): Mycotoxins in Agriculture and Food; Fungal and yeast genetics research; Microbial Natural Products and Biosynthesis
TL;DR: AflJ appears to modulate the regulation of early genes in aflatoxin biosynthesis and lead to an increase in early pathway intermediates. (via Semantic Scholar)
Source: Web Of Science
Added: August 6, 2018

2007 article

The effect of elevated temperature on gene transcription and aflatoxin biosynthesis

OBrian, G. R., Georgianna, D. R., Wilkinson, J. R., Yu, J., Abbas, H. K., Bhatnagar, D., … Payne, G. A. (2007, March 1). Mycologia.

By: G. OBrian n, D. Georgianna n, J. Wilkinson*, J. Yu *, H. Abbas *, D. Bhatnagar, T. Cleveland *, W. Nierman, G. Payne n

author keywords: AFLR; biosynthesis; micro-arrays
MeSH headings : Aflatoxins / biosynthesis; Aflatoxins / genetics; Aspergillus flavus / genetics; Aspergillus flavus / physiology; DNA-Binding Proteins / genetics; Fungal Proteins / genetics; Gene Expression Profiling; Gene Expression Regulation, Fungal; Hot Temperature; Polymerase Chain Reaction; Transcription Factors / genetics
topics (OpenAlex): Mycotoxins in Agriculture and Food; Plant Pathogens and Fungal Diseases; Fungal and yeast genetics research
TL;DR: Data indicate that the failure of A. flavus to produce aflatoxin at 37 C is not due to lack of transcription of aflR or aflS, and that AFLR is nonfunctional at high temperatures, suggesting that the factor(s) sensing the elevated temperatures must be acute. (via Semantic Scholar)
Source: Web Of Science
Added: August 6, 2018

2005 article

Aflatoxin Production in Peanut Lines Selected To Represent a Range of Linoleic Acid Concentrations

Xue, H. Q., Isleib, T. G., Payne, G. A., Novitzky, W. F., & Obrian, G. (2005, January 1). Journal of Food Protection.

By: H. Xue n, T. Isleib n, G. Payne n, W. Novitzky n & G. Obrian n

MeSH headings : Aflatoxins / analysis; Aflatoxins / biosynthesis; Arachis / genetics; Aspergillus flavus / growth & development; Aspergillus flavus / metabolism; Consumer Product Safety; Fatty Acids, Unsaturated / analysis; Fatty Acids, Unsaturated / pharmacology; Food Contamination / analysis; Food Microbiology; Genetic Variation; Humans; Linoleic Acid / analysis; Linoleic Acid / pharmacology; Peanut Oil; Plant Oils / chemistry; Predictive Value of Tests; Regression Analysis
topics (OpenAlex): Peanut Plant Research Studies; Mycotoxins in Agriculture and Food; Listeria monocytogenes in Food Safety
TL;DR: Although fatty acid concentrations accounted for significant portions of genetic variation, it is not practical to use them as predictors for susceptibility to aflatoxin contamination, especially for lines in the normal range for oleate and linoleate. (via Semantic Scholar)
UN Sustainable Development Goals Color Wheel
UN Sustainable Development Goal Categories
2. Zero Hunger (OpenAlex)
Source: Web Of Science
Added: August 6, 2018

2003 article

Comparison of Aflatoxin Production in Normal- and High-Oleic Backcross-Derived Peanut Lines

Xue, H. Q., Isleib, T. G., Payne, G. A., Wilson, R. F., Novitzky, W. P., & O'Brian, G. (2003, November 1). Plant Disease.

By: H. Xue*, T. Isleib*, G. Payne*, R. Wilson*, W. Novitzky* & G. O'Brian*

author keywords: Arachis hypogaea
topics (OpenAlex): Peanut Plant Research Studies; Listeria monocytogenes in Food Safety; Plant Disease Management Techniques
TL;DR: Special care should be taken with high-oleic lines to prevent growth of Aspergillus spp. (via Semantic Scholar)
UN Sustainable Development Goals Color Wheel
UN Sustainable Development Goal Categories
2. Zero Hunger (OpenAlex)
Source: Web Of Science
Added: August 6, 2018

2003 article

Identification of genes differentially expressed during aflatoxin biosynthesis in Aspergillus flavus and Aspergillus parasiticus

OBrian, G. R., Fakhoury, A. M., & Payne, G. A. (2003, April 7). Fungal Genetics and Biology.

By: G. OBrian n, A. Fakhoury n & G. Payne n

author keywords: aflatoxin; Aspergillus; ESTs; microarrays
MeSH headings : Aflatoxins / biosynthesis; Aflatoxins / genetics; Aspergillus / genetics; Aspergillus / metabolism; Aspergillus flavus / genetics; Aspergillus flavus / metabolism; DNA, Complementary / analysis; DNA, Fungal / analysis; Expressed Sequence Tags; Gene Deletion; Gene Expression Profiling; Genes, Fungal; Molecular Sequence Data; Oligonucleotide Array Sequence Analysis; RNA, Fungal / genetics; RNA, Messenger / analysis
topics (OpenAlex): Mycotoxins in Agriculture and Food; Gene expression and cancer classification; Molecular Biology Techniques and Applications
TL;DR: Gene expression analysis of Aspergillus parasiticus grown under conditions conducive and non-conductive for aflatoxin production was evaluated using glass slide microarrays containing the 753 ESTs and no predicted function could be ascribed to 18 of the 24 genes whose elevated expression was associated with a flatoxin biosynthesis. (via Semantic Scholar)
Source: Web Of Science
Added: August 6, 2018

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