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Mbadinga Mbadinga, D. L.

Publications and source records attributed to Mbadinga Mbadinga, D. L..

2 recordsLinked to original sources

Global non-animal peroxidases analysis provides insights into the evolutionary study of this gene family in green lineage

The non-animal peroxidases belong to a superfamily of oxidoreductases that reduce the hydrogen peroxide and oxidize numerous substrates. Since their initial characterization in 1992, several advances have provided an understanding into the origin and evolutionary history of this family of proteins. Here, we report for the first time an exhaustive evolutionary analysis of non-animal peroxidases using integrated in silico and biochemical strategies. Thanks to the availability of numerous genomic sequences from many species belonging to different kingdoms together with expert and exhaustive annotation of peroxidase sequences centralized in a dedicated database, we have deepened our understanding of the evolutionary process underlying non-animal peroxidases through phylogenetic reconstructions. We analysed the distribution of all non-animal peroxidases in more than 200 eukaryotic organisms in silico. First, we show that the presence or absence of non-animal peroxidases can be correlated with the presence or absence of certain organelles or with specific biological processes. Examining a wide range of organisms, we confirmed that ascorbate peroxidases (APx) and cytochromes c peroxidases (CcP) were detected respectively in chloroplast and mitochondria containing organisms. Plants, which contain both organelles, are an exception and contain only APxs without CcP. Class III peroxidases (CIII Prx) were only detected in plants and Class II peroxidases (CII Prx) in fungi related to wood decay and plant degradation. Moreover, we demonstrate that biochemical activities (APx, CcP and CIII Prx) assayed in protein extracts obtained from 30 different eukaryotic organisms strongly support the distribution of the sequences resulting from our in silico analysis. The biochemical results confirmed both the presence and classification of non-animal peroxidase encoding sequences.

evolutionary biology

An ancestral signalling pathway is conserved in plant lineages forming intracellular symbioses

Plants are the foundation of terrestrial ecosystems and their colonization of land was facilitated by mutualistic associations with arbuscular mycorrhizal fungi. Following that founding event, plant diversification has led to the emergence of a tremendous diversity of mutualistic symbioses with microorganisms, ranging from extracellular associations to the most intimate intracellular associations, where fungal or bacterial symbionts are hosted inside plant cells. Through analysis of 271 transcriptomes and 122 plant genomes, we demonstrate that the common symbiosis signalling pathway controlling the association with arbuscular mycorrhizal fungi and with nitrogen-fixing bacteria specifically co-evolved with intracellular endosymbioses, including ericoid and orchid mycorrhizae in angiosperms and ericoid-like associations of bryophytes. In contrast, species forming exclusively extracellular symbioses like ectomycorrhizae or associations with cyanobacteria have lost this signalling pathway. This work unifies intracellular symbioses, revealing conservation in their evolution across 450 million years of plant diversification.

plant biology