Abstract
Heme peroxidases and catalases are key enzymes of hydrogen peroxide metabolism and signaling. Here, the reconstruction of the molecular evolution of the peroxidase–catalase superfamily (annotated in pfam as PF00141) based on experimentally verified as well as numerous newly available genomic sequences is presented. The robust phylogenetic tree of this large enzyme superfamily was obtained from 490 full-length protein sequences. Besides already well-known families of heme b peroxidases arranged in three main structural classes, completely new (hybrid type) peroxidase families are described being located at the border of these classes as well as forming (so far missing) links between them. Hybrid-type A peroxidases represent a minor eukaryotic subfamily from Excavates, Stramenopiles and Rhizaria sharing enzymatic and structural features of ascorbate and cytochrome c peroxidases. Hybrid-type B peroxidases are shown to be spread exclusively among various fungi and evolved in parallel with peroxidases in land plants. In some ascomycetous hybrid-type B peroxidases, the peroxidase domain is fused to a carbohydrate binding (WSC) domain. Both here described hybrid-type peroxidase families represent important turning points in the complex evolution of the whole peroxidase–catalase superfamily. We present and discuss their phylogeny, sequence signatures and putative biological function.
Highlights
The general presentation of this tree (Fig. 1) clearly distinguishes all three main structural classes already defined by Welinder in 1992 [6]
The phylogenetic origin of Class I is positioned among predecessors of katG genes coding for catalase–peroxidases (KatGs) from planktonic aerobic and heterotrophic bacteria [25]
The present analysis has shown that several ascorbate peroxidases (APxs) genes in Chlorophyta and higher plants lack most of the essential residues for heme binding and/or catalysis (Fig. 6a, b)
Summary
M. Zámocký Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, SK‐84551 Bratislava, Slovakia. Heme peroxidases are ubiquitous oxidoreductases present in all kingdoms of life. They can be divided in three main structural superfamilies and two minor families (overview in [1]). The three main superfamilies are the (1) peroxidase–catalase superfamily, (2) the peroxidase– cyclooxygenase superfamily [2] and (3) the CDE superfamily [3]. The latter is comprised of so-called chlorite dismutases, dye-decolorizing peroxidases and EfeB (which are heme-binding/sensoring proteins of unclear biological function).
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have