Lead and cadmium-induced oxidative stress impacting mycelial growth of Oudemansiella radicata in liquid medium alleviated by microbial siderophores

Abstract

In this study, the effects of siderophores produced by six bacteria on mycelium growth, Cd and Pb accumulation, lipid peroxidation, protein content and antioxidant enzyme in Oudemansiella radicata were investigated in Cd and Pb-containing liquid medium. The results showed that inoculation with siderophore-containing filtrates (SCF) partly enhanced the growth of O. radicata after 15 days, with 0.8-32.4% biomass increase for Cd and 0.7-20.8% for Pb compared to control(s), which lacked siderophore. The maximum enhancement for accumulation were found to be confined to Bacillus sp. FFQ2(s) (26.5%) for Cd and Pseudomonas sp. CY63(s) (158.9%) for Pb. A significant decrease in MDA content indicated that lipid peroxidation in O. radicata was alleviated by siderophores. Besides, antioxidant enzyme SOD and POD activities also displayed obviously decrease in SCF-treated mycelium compared to control(s) treatment, while CAT activity did not present significant change. Protein level in O. radicata treated by SCF increased from 0.3 to 138.0% for Cd and from 10.9 to 107.1% for Pb compared to control(s). Therefore, the present work suggests that microbial siderophores can reduce the toxicity of metals to mycelium and then alleviate heavy metals-inducing oxidative stress in O. radicata.

Microbial assisted phytoextraction of Cd2+ by Salix viminalis under in vitro culture conditions

“…Similar observation was noted by Dimpka et al (2009a) in cowpea inoculated with S. acidiscabies E13 SPB strain under Ni 2+ exposure. Another study on Oudemansiella radicata treated with the culture filtrates containing siderophores synthesized by 6 different SPB strains demonstrated a significant decline in MDA level within mycelium exposed to Cd 2+ and Pb 2+ (Cao et al, 2012). The above mentioned studies including our results indicate that under HMs contamination, the siderophores can potentially alleviate oxidative stress by binding to free ions of heavy metals.…”

“…It has been observed that the presence of Cd 2+ ions may lead to the ROS production, inducing lipid peroxidation in plants (Mishra et al, 2006;Islam et al, 2008;Xu et al, 2011). The level of MDA is an indicator of the lipid peroxidation in plants and its high accumulation is related to oxidative stress (Cao et al, 2012). In this study, we demonstrated that inoculation with all tested SPB strains considerably decreased the level of MDA accumulation in leaves, stems, and roots of S. viminalis L..…”

Impact of Acute Metal Stress in Saccharomyces cerevisiae

“…In this regard, iron homeostasis genes, especially involved in high-affinity iron transport ( FET3 and FTR1 ) and siderophore iron transport ( ARN1 , ARN2 , SIT1/ARN3 , ENB1/ARN4 , FIT1 , FIT2 , and FIT3 ; Figure 4) were induced in response to Co 2+ , Mn 2+ , Ni, 2+ and Zn 2+ . Notably, a recent study reported that siderophores can reduce metal toxicity [59]. Induction of the siderophore ion transport system might therefore serve as one further general detoxification mechanism by chelating extracellular metal ions to prevent their uptake.…”

No effect of intraspecific relatedness on public goods cooperation in a complex community

“…This discrepancy cannot be wholly explained by greater assortment within-versus between-species, given that in this study nonproducers were rescued to the same extent by conspecifics and heterospecifics. Further work to explore these opposite responses to selection at genetic and ecological scales will be key to understand long-term responses to shared public goods more generally and to explain the lack of effectiveness in using siderophore producing bacteria (as opposed to the direct addition of siderophores (e.g., Nair et al 2007;Cao et al 2012) to remediate metal-contaminated environments (Wu et al 2006;Kuffner et al 2008;Li and Ramakrishna 2011;Rojas-Tapias et al 2012).…”