Integration of Physiological, Transcriptomic and Metabolomic Reveals Molecular Mechanism of Paraisaria dubia Response to Zn2+ Stress

Abstract

Utilizing mycoremediation is an important direction for managing heavy metal pollution. Zn2+ pollution has gradually become apparent, but there are few reports about its pollution remediation. Here, the Zn2+ remediation potential of Paraisaria dubia, an anamorph of the entomopathogenic fungus Ophiocordyceps gracilis, was explored. There was 60% Zn2+ removed by Paraisaria dubia mycelia from a Zn2+-contaminated medium. To reveal the Zn2+ tolerance mechanism of Paraisaria dubia, transcriptomic and metabolomic were executed. Results showed that Zn2+ caused a series of stress responses, such as energy metabolism inhibition, oxidative stress, antioxidant defense system disruption, autophagy obstruction, and DNA damage. Moreover, metabolomic analyses showed that the biosynthesis of some metabolites was affected against Zn2+ stress. In order to improve the tolerance to Zn2+ stress, the metabolic mechanism of metal ion transport, extracellular polysaccharides (EPS) synthesis, and microcycle conidiation were activated in P. dubia. Remarkably, the formation of microcycle conidiation may be triggered by reactive oxygen species (ROS) and mitogen-activated protein kinase (MAPK) signaling pathways. This study supplemented the gap of the Zn2+ resistance mechanism of Paraisaria dubia and provided a reference for the application of Paraisaria dubia in the bioremediation of heavy metals pollution.

Comparative metabolic profiling of mycelia, fermentation broth, spore powder and fruiting bodies of Ophiocordyceps gracilis by LC–MS/MS

“…17,18 However, up to now, research on Cordyceps spores is very limited, 19 and Cordyceps spores have not been fully exploited like G. lucidum spores, which is related to the difficulty of artificial cultivation of the fruiting bodies of Cordyceps and its low spore yield. Our research team has obtained a large amount of O. gracilis spore powder through liquid fermentation by microcycle conidiation technology, 20 but the active ingredients of the spore powder are still unknown, which limits its application. To date, researchers have paid attention to major bioactive components, such as cordycepin, adenosine, and polysaccharides of cultures, and analysis of the metabolomic differences among mycelia and natural products of Cordyceps.…”

A Neutral Polysaccharide from Spores of Ophiocordyceps gracilis Regulates Oxidative Stress via NRF2/FNIP1 Pathway

“…However, polysaccharides from Cordyceps spores are less studied. In our previous studies, large quantities of O. gracilis were obtained in submerged culture via the microcycle conidiation technique [24]. Numerous studies have shown that the functions of polysaccharides are closely linked to their structural characteristics, such as monosaccharide composition, molecular weight (Mw), and chemical linkages [25,26].…”

Preface to the Special Issue ‘Heavy Metals in Mushrooms’

“…The first article of this Special Issue addresses the molecular tolerance mechanism of Paraisaria dubia to Zn 2+ stress and the possible application of Paraisaria dubia in the bioremediation of heavy metal pollution [1]. The second article analyzes the ectomycorrhizal communities in a former uranium mine and communities under experimental conditions to improve plants' tolerance to certain abiotic conditions [2].…”