Genetic regulation of aflatoxin, ochratoxin A, trichothecene, and fumonisin biosynthesis: A review

Abstract

Mycotoxins are a significant food safety concern. Aflatoxins, trichothecenes, fumonisins, and ochratoxin A are considered the most important mycotoxins due to their frequent occurrence in food products and their well-known toxicity. The regulation of mycotoxin biosynthesis occurs mainly at transcriptional level, and specific regulators have been described in every biosynthetic cluster. Secondary metabolite production, including mycotoxin synthesis, is also regulated by general regulator pathways affected by light, osmotic stress and oxidative stress, among others. This review is focused on this genetic regulation of mycotoxin biosynthesis by specific genes and global regulators.

Adverse Effects, Transformation and Channeling of Aflatoxins Into Food Raw Materials in Livestock

“…The letters B and G stand for the blue and green fluorescence of these compounds observable under ultraviolet light, when separated by thin-layer chromatography (Yu, 2012). The aflatoxin biosynthetic gene cluster is sophisticatedly regulated by both local (AflR and AflS) and global (Velvet Complex) regulatory elements (Amaike and Keller, 2011;Alkhayyat and Yu, 2014;Amare and Keller, 2014;Gil-Serna et al, 2019;Keller, 2019). Environmental factors like the availability of carbon and nitrogen sources, changing pH, temperature and light conditions as well as variations in the redox status of the fungal cells all have their impacts on aflatoxin production (Alkhayyat and Yu, 2014).…”

“…Plant-fungus interactions also affect the biosynthesis of aflatoxins e.g., through oxylipin production, which have been reviewed e.g., by Pusztahelyi et al (2015). Undoubtedly, a deeper understanding of the elements and regulation of the aflatoxin biosynthetic gene clusters operating in aflatoxigenic fungi is an important prerequisite for the development of novel and successful mycotoxin control strategies in the future (Alkhayyat and Yu, 2014;Gil-Serna et al, 2019).…”

FvatfA regulates growth, stress tolerance as well as mycotoxin and pigment productions in Fusarium verticillioides

“…Fumonisins may also cause oesophageal (Kamangar et al 2009;Kigen et al 2017) and renal (Müller et al 2012;Wu et al 2014;Barnett and Cummings 2018) cancers as well as neural tube defects (Wu et al 2014;Ponce-García et al 2018;Lumsangkul et al 2019). A deeper understanding of the molecular regulation of fumonisin biosynthesis in toxigenic fusaria (Butchko et al 2012;Lazzaro et al 2012;Woloshuk and Shim 2013;Gu et al 2017;Gil-Serna et al 2019) may lead to the development of atoxigenic strains with possible biocontrol potential or to the utilization of RNA interference technologies to silence mycotoxin biosynthesis genes (Alberts et al 2016).…”

Investigating the Efficiency of Hydroxycinnamic Acids to Inhibit the Production of Enniatins by Fusarium avenaceum and Modulate the Expression of Enniatins Biosynthetic Genes

“…The mechanism that can explain the high efficiency of FER to modulate the expression of esyn1 needs to be elucidated. One hypothesis could be linked to the capacity of FER to alleviate oxidative stress which has been shown to activate the biosynthesis of various mycotoxins and increase the expression of biosynthetic genes [44,45]. From a mechanistic perspective, several reports have evidenced that transcription factors homologs of Yap1 in S. cerevisiae played a key role in fungal tolerance to oxidative stress and promoted the production of toxins [46,47].…”