Genomes and Genes
Experts and Doctors on aflatoxins in New Orleans, Louisiana, United States
Locale: New Orleans, Louisiana, United States
- Ehrlich K, Montalbano B, Cotty P. Sequence comparison of aflR from different Aspergillus species provides evidence for variability in regulation of aflatoxin production. Fungal Genet Biol. 2003;38:63-74 pubmed..Phylogenetic analyses also suggest that isolates currently assigned to the A. flavus morphotype SBG represent a distinct species and that A. nomius is a diverse paraphyletic assemblage likely to contain several species. ..
- Yu J, Mohawed S, Bhatnagar D, Cleveland T. Substrate-induced lipase gene expression and aflatoxin production in Aspergillus parasiticus and Aspergillus flavus. J Appl Microbiol. 2003;95:1334-42 pubmed..Lipid substrate induces and promotes aflatoxin formation. It gives insight into genetic and biochemical aspects of aflatoxin formation. ..
- Chang P, Yu J, Yu J. aflT, a MFS transporter-encoding gene located in the aflatoxin gene cluster, does not have a significant role in aflatoxin secretion. Fungal Genet Biol. 2004;41:911-20 pubmed..The FadA-dependent G-protein signaling pathway previously shown to govern aflatoxin biosynthesis and sporulation plays a role in the regulation of aflT expression. ..
- Chang P, Ehrlich K, Hua S. Cladal relatedness among Aspergillus oryzae isolates and Aspergillus flavus S and L morphotype isolates. Int J Food Microbiol. 2006;108:172-7 pubmed..flavus isolates. Our results show that A. flavus populations are genetically diverse. A. oryzae isolates may descend from certain atoxigenic L-type A. flavus isolates. ..
- Chang P, Scharfenstein L, Li P, Ehrlich K. Aspergillus flavus VelB acts distinctly from VeA in conidiation and may coordinate with FluG to modulate sclerotial production. Fungal Genet Biol. 2013;58-59:71-9 pubmed publisher..Concerted interactions of A. flavus VeA and VelB with LaeA are critical for conidiation and aflatoxin biosynthesis. VelB may have a dual role and likely coordinates with FluG to modulate sclerotial production. ..
- Mellon J, Dowd M, Beltz S. Effects of temperature and medium composition on inhibitory activities of gossypol-related compounds against aflatoxigenic fungi. J Appl Microbiol. 2013;115:179-86 pubmed publisher..Studies utilizing gossypol-related compounds as inhibitory agents of biological activities should be interpreted with caution due to compound interaction with multiple components of the test system, especially serum proteins. ..
- Chang P, Scharfenstein L, Mack B, Ehrlich K. Deletion of the Aspergillus flavus orthologue of A. nidulans fluG reduces conidiation and promotes production of sclerotia but does not abolish aflatoxin biosynthesis. Appl Environ Microbiol. 2012;78:7557-63 pubmed publisher..flavus. These results suggest that the function of fluG and the signaling pathways related to conidiation are different in the two related aspergilli. ..
- Chang P, Abbas H, Weaver M, Ehrlich K, Scharfenstein L, Cotty P. Identification of genetic defects in the atoxigenic biocontrol strain Aspergillus flavus K49 reveals the presence of a competitive recombinant group in field populations. Int J Food Microbiol. 2012;154:192-6 pubmed publisher..This finding provides an easy way to select future biocontrol strains from the reservoir of non-aflatoxigenic populations in agricultural fields. ..
- Wilkinson J, Kale S, Bhatnagar D, Yu J, Ehrlich K. Expression profiling of non-aflatoxigenic Aspergillus parasiticus mutants obtained by 5-azacytosine treatment or serial mycelial transfer. Toxins (Basel). 2011;3:932-48 pubmed publisher..Based on this result we hypothesize that the treatments cause changes in the structure of cellular and organelle membranes that prevent normal development and aflatoxin biosynthesis. ..
- Yu J, Ronning C, Wilkinson J, Campbell B, Payne G, Bhatnagar D, et al. Gene profiling for studying the mechanism of aflatoxin biosynthesis in Aspergillus flavus and A. parasiticus. Food Addit Contam. 2007;24:1035-42 pubmed..flavus and A. parasiticus. Genes consistently expressed in several aflatoxin-supportive media are reported. ..
- Chang P, Wilkinson J, Horn B, Yu J, Bhatnagar D, Cleveland T. Genes differentially expressed by Aspergillus flavus strains after loss of aflatoxin production by serial transfers. Appl Microbiol Biotechnol. 2007;77:917-25 pubmed..Possible roles of hcc and other identified genes are discussed in relation to regulation of aflatoxin biosynthesis. ..
- Chang P, Ehrlich K. What does genetic diversity of Aspergillus flavus tell us about Aspergillus oryzae?. Int J Food Microbiol. 2010;138:189-99 pubmed publisher..flavus and A. oryzae genomes, the genetic diversity in A. flavus and A. oryzae populations, the causes of this diversity, and the relatedness of nonaflatoxigenic A. flavus strains to A. oryzae...
- Ehrlich K, Chang P, Scharfenstein L, Cary J, Crawford J, Townsend C. Absence of the aflatoxin biosynthesis gene, norA, allows accumulation of deoxyaflatoxin B1 in Aspergillus flavus cultures. FEMS Microbiol Lett. 2010;305:65-70 pubmed publisher..flavus. ..
- Brown R, Chen Z, Warburton M, Luo M, Menkir A, Fakhoury A, et al. Discovery and characterization of proteins associated with aflatoxin-resistance: evaluating their potential as breeding markers. Toxins (Basel). 2010;2:919-33 pubmed publisher..Several resistant lines have been subjected to QTL mapping to identify loci associated with the aflatoxin-resistance phenotype. Results of proteome and characterization studies are discussed. ..
- Chang P, Scharfenstein L, Luo M, Mahoney N, Molyneux R, Yu J, et al. Loss of msnA, a putative stress regulatory gene, in Aspergillus parasiticus and Aspergillus flavus increased production of conidia, aflatoxins and kojic acid. Toxins (Basel). 2011;3:82-104 pubmed publisher..flavus. The msnA gene appears to be required for the maintenance of the normal oxidative state. The impairment of msnA resulted in the aforementioned changes, which might be used to combat the increased oxidative stress in the cells. ..
- Cary J, Rajasekaran K, Brown R, Luo M, Chen Z, Bhatnagar D. Developing resistance to aflatoxin in maize and cottonseed. Toxins (Basel). 2011;3:678-96 pubmed publisher..This review will present information on preharvest control strategies that utilize both breeding and native resistance identification approaches in maize as well as transgenic approaches in cotton...
- Cary J, Ehrlich K, Beltz S, Harris Coward P, Klich M. Characterization of the Aspergillus ochraceoroseus aflatoxin/sterigmatocystin biosynthetic gene cluster. Mycologia. 2009;101:352-62 pubmed..ochraceoroseus aflR restored ST production in A. nidulans transformants. PCR amplification of A. rambellii genomic DNA demonstrated that the AF/ST gene cluster is organized in the same manner as that of A. ochraceoroseus...
- Chang P, Horn B, Dorner J. Clustered genes involved in cyclopiazonic acid production are next to the aflatoxin biosynthesis gene cluster in Aspergillus flavus. Fungal Genet Biol. 2009;46:176-82 pubmed publisher..flavus strain. Therefore, some of the CPA biosynthesis genes are organized in a mini-gene cluster that is next to the aflatoxin gene cluster in A. flavus...
- Kale S, Milde L, Trapp M, Frisvad J, Keller N, Bok J. Requirement of LaeA for secondary metabolism and sclerotial production in Aspergillus flavus. Fungal Genet Biol. 2008;45:1422-9 pubmed publisher..Transcriptional examination of the mutants showed LaeA negatively regulates expression of its recently identified nuclear partner VeA, another global regulator of A. flavus secondary metabolites and sclerotia...
- Cary J, Klich M, Beltz S. Characterization of aflatoxin-producing fungi outside of Aspergillus section Flavi. Mycologia. 2005;97:425-32 pubmed..Results showed that of the new aflatoxin-producers, Aspergillus SRRC 1468 forms a strongly supported clade with A. ochraceoroseus as does Emericella SRRC 2520 with Em. astellata SRRC 503 and 512...
- Chang P, Hua S. Molasses supplementation promotes conidiation but suppresses aflatoxin production by small sclerotial Aspergillus flavus. Lett Appl Microbiol. 2007;44:131-7 pubmed..Targeting genetic parameters in S strain A. flavus isolates may reduce aflatoxin contamination of crops by reducing the survival and toxigenicity of these strains. ..
- Bennett J, Klich M. Mycotoxins. Clin Microbiol Rev. 2003;16:497-516 pubmed..This review focuses on the most important ones associated with human and veterinary diseases, including aflatoxin, citrinin, ergot akaloids, fumonisins, ochratoxin A, patulin, trichothecenes, and zearalenone. ..
- Rajasekaran K, Cary J, Cotty P, Cleveland T. Development of a GFP-expressing Aspergillus flavus strain to study fungal invasion, colonization, and resistance in cottonseed. Mycopathologia. 2008;165:89-97 pubmed publisher..In addition, development of GFP expressing A. flavus strain provides an easy and rapid assay procedure for studying the ecology, etiology, and epidemiology of cotton boll rot caused by A. flavus resulting in aflatoxin contamination. ..
- Cary J, Harris Coward P, Ehrlich K, Mack B, Kale S, Larey C, et al. NsdC and NsdD affect Aspergillus flavus morphogenesis and aflatoxin production. Eukaryot Cell. 2012;11:1104-11 pubmed publisher..Our results support previous studies showing that there is a strong association between conidiophore and sclerotium development and aflatoxin production in A. flavus...
- Mellon J, Zelaya C, Dowd M, Beltz S, Klich M. Inhibitory effects of gossypol, gossypolone, and apogossypolone on a collection of economically important filamentous fungi. J Agric Food Chem. 2012;60:2740-5 pubmed publisher..flavus and A. parasiticus. Both gossypol and apogossypolone demonstrated significant inhibition of ochratoxin A production (47%; 91%, respectively) in cultures of A. alliaceus. ..
- Chang P, Scharfenstein L, Ehrlich K, Wei Q, Bhatnagar D, Ingber B. Effects of laeA deletion on Aspergillus flavus conidial development and hydrophobicity may contribute to loss of aflatoxin production. Fungal Biol. 2012;116:298-307 pubmed publisher..The loss of hydrophobicity and the other developmental changes in the laeA deletion mutants could affect the ability of the fungus to produce aflatoxins...
- Yu J, Fedorova N, Montalbano B, Bhatnagar D, Cleveland T, Bennett J, et al. Tight control of mycotoxin biosynthesis gene expression in Aspergillus flavus by temperature as revealed by RNA-Seq. FEMS Microbiol Lett. 2011;322:145-9 pubmed publisher..Subtle changes in the expression levels of aflS to aflR appear to control transcription activation of the aflatoxin cluster...
- Chang P, Scharfenstein L, Wei Q, Bhatnagar D. Development and refinement of a high-efficiency gene-targeting system for Aspergillus flavus. J Microbiol Methods. 2010;81:240-6 pubmed publisher..The improvement allowed gene manipulation using the reusable pyrG marker as shown by the restoration of laeA-mediated aflatoxin production in an A. flavus laeA-deleted mutant. ..