Ethanol Dehydrogenase I Contributes to Growth and Sporulation Under Low Oxygen Condition via Detoxification of Acetaldehyde in Metarhizium acridum

Abstract

The entomopathogenic fungi encounter hypoxic conditions in both nature and artificial culture. Alcohol dehydrogenases (ADHs) are a group of oxidoreductases that occur in many organisms. Here we demonstrate that an alcohol dehydrogenase I, MaADH1, in the locust-specific fungal pathogen, Metarhizium acridum, functions in acetaldehyde detoxification mechanism under hypoxic conditions in growth and sporulation. The MaADH1 was highly expressed in sporulation stage under hypoxic conditions. Compared with a wild-type strain, the ΔMaADH1 mutant showed inhibited growth and sporulation under hypoxic conditions, but no impairment under normal conditions. Under hypoxic conditions, ΔMaADH1 mutant produced significant decreased alcohol, but significant increased acetaldehyde compared to wild type. M. acridum was sensitive to exogenous acetaldehyde, exhibiting an inhibited growth and sporulation with acetaldehyde added in the medium. MaADH1 did not affect virulence. Our results indicated that the MaADH1 was critical to growth and sporulation under hypoxic stress by detoxification of acetaldehyde in M. acridum.

High-Throughput Volatilome Fingerprint Using PTR–ToF–MS Shows Species-Specific Patterns in Mortierella and Closely Related Genera

“…Acetaldehyde and different types of alcohols were generally high in relative concentration across all Mortierella s. l. strains ( Table 3 ). These compounds’ reported functions vary among fungal species, but they certainly play a role in stress response and/or defense mechanisms [ 46 ].…”

Functional Analysis of Keto-Acid Reductoisomerase ILVC in the Entomopathogenic Fungus Metarhizium robertsii

“…DEGs with higher expression levels in mycelial growth than inhibited samples were listed in Table 3 . Some genes involved in mycelial growth, such as Alcohol dehydrogenase , catalase A and chitinase were lower expressed in CZA than other samples [ 26 , 27 , 28 ].…”

“…DEGs with higher expression levels in mycelial growth than inhibited samples were listed in Table 3. Some genes involved in mycelial growth, such as Alcohol dehydrogenase, catalase A and chitinase were lower expressed in CZA than other samples [26][27][28]. In addition, 20 genes involved in conidial germination or mycelial growth were shown to be up-regulated in WT/CZA, CZA + AA/CZA, and CZA + yeast/CZA from RNA-Seq data.…”

Fungal Alcohol Dehydrogenases: Physiological Function, Molecular Properties, Regulation of Their Production, and Biotechnological Potential

“…In A. nidulans , the alcC gene encoding AdhIIIp is regulated at both the transcriptional and translational levels, induced by anaerobic stress, and required for long-term survival under these anaerobic conditions [ 39 ]. In the entomopathogenic fungus Metarhizium acridum, the Adh1 gene is similarly regulated by oxygen; under hypoxic conditions, the Adh1 gene is up-regulated [ 40 ].…”

“…The authors suggested that Adh1p activity is required to penetrate and colonize P. xylostella larvae. However, Zhang et al [ 40 ] reported that in M. acridum, the Adh1 gene is not involved in the virulence of Locusta migratoria . In C. albicans, [ 86 ] reported reduced ADH1 gene expression and a lower presence of Adh1p in Candida biofilm cells than in planktonic cells.…”