The Genomic Regions That Contain Ochratoxin A Biosynthetic Genes Widely Differ in Aspergillus Section Circumdati

Related Experiment Video

Updated: Nov 28, 2025

RNAi-mediated Control of Aflatoxins in Peanut: Method to Analyze Mycotoxin Production and Transgene Expression in the Peanut/Aspergillus Pathosystem
09:44

RNAi-mediated Control of Aflatoxins in Peanut: Method to Analyze Mycotoxin Production and Transgene Expression in the Peanut/Aspergillus Pathosystem

Published on: December 21, 2015

21.3K

Jéssica Gil-Serna1, Covadonga Vázquez1, Belén Patiño1

  • 1Department of Genetics, Physiology, and Microbiology, Faculty of Biology, University Complutense of Madrid, Jose Antonio Nováis 12, 28040 Madrid, Spain.

Toxins
|December 2, 2020
PubMed

Insights

Certain Aspergillus species within section Circumdati may produce ochratoxin A (OTA). Genome analysis reveals some species possess a complete OTA gene cluster, indicating potential toxin synthesis, while others have a truncated version, suggesting inability to produce OTA.

Area of Science:

  • Mycology
  • Genomics
  • Food Safety

Background:

  • Aspergillus section Circumdati comprises 27 species, with some implicated as ochratoxin A (OTA) producers.
  • Significant debate exists regarding the actual OTA synthesis capabilities of various species within this section.
  • Understanding the genetic basis of OTA production is crucial for food safety and risk assessment.

Purpose of the Study:

  • To investigate the ochratoxin A (OTA) biosynthetic gene cluster across 13 species of Aspergillus section Circumdati.
  • To compare the identified gene clusters with those previously characterized in Aspergillus steynii and Aspergillus westerdijkiae.
  • To correlate the presence and integrity of the OTA gene cluster with the potential for OTA production in these species.

Main Methods:

  • Whole-genome sequencing and analysis of 13 Aspergillus section Circumdati species.
  • Bioinformatic identification and characterization of the ochratoxin A (OTA) biosynthetic gene cluster.
  • Comparative genomics to assess gene cluster integrity and identify variations across species.

Main Results:

  • Seven species, including A. affinis, A. cretensis, A. elegans, A. muricatus, A. pulvericola, A. roseoglobulosus, and A. subramanianii, possess a potentially functional OTA biosynthetic gene cluster.
  • Seven other species, namely A. melleus, A. ochraceus, A. ostianus, A. persii, A. sclerotiorum, A. sesamicola, and A. westlandensis, exhibit a truncated OTA gene cluster lacking essential biosynthesis genes.
  • The pattern of gene gain and loss within the OTA cluster varies significantly among species, suggesting independent evolutionary events.

Conclusions:

  • Species within Aspergillus section Circumdati exhibit diverse genetic architectures of the ochratoxin A (OTA) biosynthetic gene cluster.
  • The presence of a complete gene cluster suggests a potential for OTA synthesis in species like A. affinis and A. pulvericola.
  • Truncated gene clusters in species such as A. ochraceus and A. melleus likely explain their inability to produce OTA, highlighting evolutionary divergence.
Keywords:
Aspergillus ochraceusAspergillus steyniiAspergillus westerdijkiaebiosynthetic clusterochratoxin A

More Related Videos

Isolation of Culturable Yeasts and Molds from Soils to Investigate Fungal Population Structure10:33

Isolation of Culturable Yeasts and Molds from Soils to Investigate Fungal Population Structure

Published on: May 27, 2022

6.4K
Inhibition of Aspergillus flavus Growth and Aflatoxin Production in Transgenic Maize Expressing the α-amylase Inhibitor from Lablab purpureus L.09:21

Inhibition of Aspergillus flavus Growth and Aflatoxin Production in Transgenic Maize Expressing the α-amylase Inhibitor from Lablab purpureus L.

Published on: February 15, 2019

10.9K

Related Concept Videos

Fungal Phylum Ascomycota01:28

Fungal Phylum Ascomycota

Phylum Ascomycota, a major division within the subkingdom Dikarya, comprises a diverse range of fungal species, including both unicellular yeasts and filamentous molds such as Aspergillus and Penicillium. These fungi thrive in a variety of habitats, from aquatic ecosystems to terrestrial environments, playing crucial ecological and economic roles.Morphology and ReproductionThe defining characteristic of Ascomycetes, commonly referred to as sac fungi, is the ascus—a sac-like structure that...
668
Exon Recombination02:32

Exon Recombination

The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes. 
Exon shuffling follows “splice frame rules.” Each exon...
3.9K
Prokaryotic Transcriptional Activators and Repressors01:58

Prokaryotic Transcriptional Activators and Repressors

The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
24.5K
Operons02:09

Operons

Prokaryotes can control gene expression through operons—DNA sequences consisting of regulatory elements and clustered, functionally related protein-coding genes. Operons use a single promoter sequence to initiate transcription of a gene cluster (i.e., a group of structural genes) into a single mRNA molecule. The terminator sequence ends transcription. An operator sequence, located between the promoter and structural genes, prohibits the operon’s transcriptional activity if bound by...
53.1K
Fungal Group Zygomycota01:29

Fungal Group Zygomycota

Zygomycota, previously classified as a distinct fungal group, are primarily terrestrial, saprophytic molds that play a crucial role as decomposers. Recent phylogenetic studies have revealed that these fungi are now divided into two major clades — Mucoromycota, which includes many symbiotic species, and Zoopagomycota, which primarily consists of parasitic and pathogenic fungi. These groups exhibit distinct ecological roles and reproductive strategies while sharing key structural and...
703
Gene Regulation During Sporulation01:17

Gene Regulation During Sporulation

Sporulation is a complex developmental process that allows certain Gram-positive bacteria, such as Bacillus subtilis and Clostridium species, to survive extreme environmental conditions. This process is tightly regulated by a series of signaling cascades and transcriptional controls, ensuring the formation of a highly resistant endospore.Sporulation is triggered by unfavorable conditions, such as nutrient depletion, and is governed by a phosphorelay system. One of the sensor kinases, such as...
272