Molecular profile of non-aflatoxigenic phenotype in native strains of Aspergillus flavus

被引:14
作者
Rao, K. Raksha [1 ,2 ]
Vipin, A. V. [1 ,2 ]
Venkateswaran, G. [1 ,2 ]
机构
[1] CSIR, Cent Food Technol Res Inst, Microbiol & Fermentat Technol, Mysuru 570020, Karnataka, India
[2] Acad Sci & Innovat Res AcSIR, CSIR Cent Food Technol Res Inst Campus, Mysuru 570020, Karnataka, India
关键词
Aflatoxin; Aspergillus flavus; Non-aflatoxigenic; Aflatoxin biosynthesis pathway; REAL-TIME PCR; BIOLOGICAL-CONTROL; MULTIPLEX PCR; SECTION FLAVI; RT-PCR; IDENTIFICATION; GENES; FUNGI; DIFFERENTIATION; ASSOCIATION;
D O I
10.1007/s00203-020-01822-1
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
Aflatoxins are the most common mycotoxin contaminant reported in food and feed. Aflatoxin B-1, the most toxic among different aflatoxins, is known to cause hepatocellular carcinoma in animals. Aspergillus flavus and A. parasiticus are the main producers of aflatoxins and are widely distributed in tropical countries. Even though several robust strategies have been in use to control aflatoxin contamination, the control at the pre-harvest level is primitive and incompetent. Therefore, the aim of the study was to isolate and identify the non-aflatoxigenic A. flavus and to delineate the molecular mechanism for the loss of aflatoxin production by the non-aflatoxigenic isolates. Eighteen non-aflatoxigenic strains were isolated from various biological sources using cultural and analytical methods. Among the 18 isolates, 8 isolates produced sclerotia and 17 isolates had type I deletion in norB-cypA region. The isolates were confirmed as A. flavus using gene-specific PCR and sequencing of the ITS region. Later, aflatoxin gene-specific PCR revealed that the defect in one or more genes has led to non-aflatoxigenic phenotype. The strain R9 had maximum defect, and genes avnA and verB had the highest frequency of defect among the non-aflatoxigenic strains. Further, qRT-PCR confirmed that the non-aflatoxigenic strains had high frequency of defect or downregulation in the late pathway genes compared to early pathway genes. Thus, these non-aflatoxigenic strains can be the potential candidates for an effective and proficient strategy for the control of pre-harvest aflatoxin contamination.
引用
收藏
页码:1143 / 1155
页数:13
相关论文
共 59 条
[1]   Relationships between aflatoxin production and sclerotia formation among isolates of Aspergillus section Flavi from the Mississippi Delta [J].
Abbas, HK ;
Weaver, MA ;
Zablotowicz, RM ;
Horn, BW ;
Shier, WT .
EUROPEAN JOURNAL OF PLANT PATHOLOGY, 2005, 112 (03) :283-287
[2]   Cultural methods for aflatoxin detection [J].
Abbas, HK ;
Shier, WT ;
Horn, BW ;
Weaver, MA .
JOURNAL OF TOXICOLOGY-TOXIN REVIEWS, 2004, 23 (2-3) :295-315
[3]   Comparison of cultural and analytical methods for determination of aflatoxin production by Mississippi Delta Aspergillus isolates [J].
Abbas, HK ;
Zablotowicz, RM ;
Weaver, MA ;
Horn, BW ;
Xie, W ;
Shier, WT .
CANADIAN JOURNAL OF MICROBIOLOGY, 2004, 50 (03) :193-199
[4]   Aspergillus flavus [J].
Amaike, Saori ;
Keller, Nancy P. .
ANNUAL REVIEW OF PHYTOPATHOLOGY, VOL 49, 2011, 49 :107-133
[5]  
[Anonymous], 1990, PCR Protocols: A Guide to Methods and Applications
[6]  
[Anonymous], 2002, IARC MONOGR EVAL CAR
[7]   Heatmapper: web-enabled heat mapping for all [J].
Babicki, Sasha ;
Arndt, David ;
Marcu, Ana ;
Liang, Yongjie ;
Grant, Jason R. ;
Maciejewski, Adam ;
Wishart, David S. .
NUCLEIC ACIDS RESEARCH, 2016, 44 (W1) :W147-W153
[8]   GENETIC DIVERSITY IN ASPERGILLUS-FLAVUS - ASSOCIATION WITH AFLATOXIN PRODUCTION AND MORPHOLOGY [J].
BAYMAN, P ;
COTTY, PJ .
CANADIAN JOURNAL OF BOTANY-REVUE CANADIENNE DE BOTANIQUE, 1993, 71 (01) :23-31
[9]   Genes differentially expressed by Aspergillus flavus strains after loss of aflatoxin production by serial transfers [J].
Chang, Perng-Kuang ;
Wilkinson, Jeffery R. ;
Horn, Bruce W. ;
Yu, Jiujiang ;
Bhatnagar, Deepak ;
Cleveland, Thomas E. .
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 2007, 77 (04) :917-925
[10]   Cladal relatedness among Aspergillus oryzae isolates and Aspergillus flavus S and L morphotype isolates [J].
Chang, PK ;
Ehrlich, KC ;
Hua, SST .
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY, 2006, 108 (02) :172-177