Proteomic and Secretomic Response of an African Armillaria Species to Iron

TL;DR

This study explores how an African Armillaria fungus responds to iron, revealing changes in proteins and secreted molecules that could help control its pathogenicity.

Contribution

The study identifies iron-responsive proteomic and secretomic changes and three putative siderophore biosynthetic gene clusters in an Armillaria species.

Findings

Iron supplementation caused significant changes in proteins related to metabolism and growth.

No oxidative stress response was observed at 100 μM iron.

Three putative siderophore biosynthetic gene clusters were identified and some were expressed.

Abstract

Armillaria species have
attracted
considerable research interest, because they are widely distributed,
mostly plant-pathogenic, and exhibit unique characteristics. Abiotic
factors influence intra- and interspecies variations in pathogenicity
and/or virulence of these fungi. However, the mechanisms involved
in causing these variations are not well understood. Iron is an indispensable
element in several molecular and biological processes. Yet, excessive
abundance of iron can be toxic to organisms due to Fenton-like reactions.
This study aimed to gain insights into the type and extent of iron-responsive
proteomic and secretomic changes in Armillaria sp. strain CMW4456 cultured in liquid media supplemented with iron
using a multiomics approach. Significant iron-dependent alterations
of proteins involved in metabolism and growth were observed in the
proteomes and secretomes. Iron supplementation at 100 μM did
not elicit an oxidative stress response by the fungus. Our analyses
revealed three putative siderophore biosynthetic gene clusters (BGCs)
in the genome and expression of proteins encoded by some BGC genes
in the proteome. This knowledge contributes to a better understanding
of the mechanisms employed by an Armillaria sp. in response to iron, gives insights into possible modes for
inhibiting or attenuating the pathogenicity and/or virulence of Armillaria spp., and can be valorized for more biotechnological
applications.

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