Evolution of the Tetrapyrrole Biosynthetic Pathway in Secondary Algae: Conservation, Redundancy and Replacement

0467642 - BC 2017 RIV US eng J - Journal Article
Cihlář, Jaromír - Füssy, Zoltán - Horák, Aleš - Oborník, Miroslav
Evolution of the Tetrapyrrole Biosynthetic Pathway in Secondary Algae: Conservation, Redundancy and Replacement.
PLoS ONE. Roč. 11, č. 11 (2016), č. článku e0166338. ISSN 1932-6203. E-ISSN 1932-6203
R&D Projects: GA ČR GAP506/12/1522
Institutional support: RVO:60077344
Keywords : delta aminolevulinic acid * plastid evolution * Euglena gracilis * gene transfer * diatom endosymbionts * Bigelowiella natans * chloroplast genome * sequence alignment * nuclear genomes * protein import
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 2.806, year: 2016

Tetrapyrroles such as chlorophyll and heme are indispensable for life because they are involved in energy fixation and consumption, i.e. photosynthesis and oxidative phosphorylation. In eukaryotes, the tetrapyrrole biosynthetic pathway is shaped by past endosymbioses. We investigated the origins and predicted locations of the enzymes of the heme pathway in the chlorarachniophyte Bigelowiella natans, the cryptophyte Guillardia theta, the "green" dinoflagellate Lepidodinium chlorophorum, and three dinoflagellates with diatom endosymbionts ("dinotoms"): Durinskia baltica, Glenodinium foliaceum and Kryptoperidinium foliaceum. Bigelowiella natans appears to contain two separate heme pathways analogous to those found in Euglena gracilis; one is predicted to be mitochondrial-cytosolic, while the second is predicted to be plastid-located. In the remaining algae, only plastid-type tetrapyrrole synthesis is present, with a single remnant of the mitochondrial-cytosolic pathway, a ferrochelatase of G. theta putatively located in the mitochondrion. The green dinoflagellate contains a single pathway composed of mostly rhodophyte-origin enzymes, and the dinotoms hold two heme pathways of apparently plastidal origin. We suggest that heme pathway enzymes in B. natans and L. chlorophorum share a predominantly rhodophytic origin. This implies the ancient presence of a rhodophyte-derived plastid in the chlorarachniophyte alga, analogous to the green dinoflagellate, or an exceptionally massive horizontal gene transfer.
Permanent Link: http://hdl.handle.net/11104/0265712