Species-specific Cd-stress Response in the White Rot Basidiomycetes Abortiporus biennis and Cerrena unicolor

Abstract

The effect of cadmium (Cd) on fungal growth, Cd bioaccumulation and biosorption, and on the formation of potential heavy metal response indicators such as thiols, oxalate, and laccase was investigated in the white rot fungi Cerrena unicolor andAbortiporus biennis. Only the highest Cd concentration employed (200 microM) inhibited growth of C. unicolor, whereas already lower Cd concentrations caused decreasing mycelia dry weights in A. biennis. Cd biosorption onto the mycelial surface was the predominant Cd sequestration mechanism in C. unicolor. Surface-bound and bioaccumulated Cd concentrations were essentially in the same range in A. biennis, leading to considerably higher intracellular Cd concentrations in A. biennis than in C. unicolor. Oxalate and laccase were produced by both of the fungal strains and their extracellular levels were elevated upon Cd exposure. Oxalate concentrations and laccase titres were considerably higher in C. unicolor than in A. biennis. Both fungi responded to increasing Cd concentrations by increasing intracellular amounts of thiol compounds (cysteine, gamma-glutamylcysteine, glutathione in both its reduced and oxidized form) but Cd application increased the amounts of thiols to a higher extend in A. biennis. Taken together, these species-specific responses towards Cd suggest that C. unicolor possesses a more efficient system than A. biennis to keep intracellular Cd concentrations low.

An Investigation on Tolerance and Biosorption Potential of Aspergillus awamori ZU JQ 965830.1 to Cu(II)

“…Oxalate secretion is well-documented in both brown-rot, white-rot and A.niger and this process seems to be stimulated under Cu(II) stress Green, 2003 andJarosz-Wilkolazka et al, 2006). HPLC chromatograms of control and Cu(II)-stressed samples (Fig.…”

Bacteria and Fungi as Alternatives for Remediation of Water Resources Polluting Heavy Metals

“…Therefore, biosorbents made from these fungi can be easily accepted by public when applied practically. The potential of wood rotting fungi to remove metal ions is limited to a few examples in comparison with micromycetes and the role of macromycetes in this field has been known only for few decades (Veit et al, 2005;Jarosz-Wilkolazka et al, 2006;Gonen et al, 2008;Vimala and Das, 2009). White-rot fungi are capable of accumulating high levels of heavy metals from the environment (Baldrian, 2003).…”

The stability of Pb species during the Pb removal process by growing cells of Phanerochaete chrysosporium

“…White-rot fungi have been well known for their strong degradation of various xenobiotics (Barr and Aust 1994;Huang et al 2008), while they have also been investigated with a great interest on the removing of heavy metals from wastewater in recent decades (Jarosz-Wilkołazka et al 2006;Kahraman et al 2005;Say et al 2001;Xu et al 2012). In those pieces of research, mature fungal mycelium was utilized originally or pretreated with chemical or as the base of biomaterials.…”