The plastid genome of some eustigmatophyte algae harbours a bacteria-derived six-gene cluster for biosynthesis of a novel secondary metabolite

0473017 - ÚMG 2017 RIV GB eng J - Journal Article
Yurchenko, T. - Ševčíková, T. - Strnad, Hynek - Butenko, A. - Eliáš, M.
The plastid genome of some eustigmatophyte algae harbours a bacteria-derived six-gene cluster for biosynthesis of a novel secondary metabolite.
Open Biology. Roč. 6, č. 11 (2016), č. článku 160249. E-ISSN 2046-2441
R&D Projects: GA ČR GA13-33039S; GA MŠMT(CZ) ED2.1.00/19.0388; GA MŠMT(CZ) LO1208
EU Projects: European Commission 642575
Institutional support: RVO:68378050
Keywords : Eustigmatophyceae * horizontal gene transfer * plastid genome * secondary metabolism * sugar phosphate cyclase superfamily * UbiA superfamily
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 3.481, year: 2016

Acquisition of genes by plastid genomes (plastomes) via horizontal gene transfer (HGT) seems to be a rare phenomenon. Here, we report an interesting case of HGT revealed by sequencing the plastomes of the eustigmatophyte algae Monodopsis sp. MarTras21 and Vischeria sp. CAUP Q 202. These plastomes proved to harbour a unique cluster of six genes, most probably acquired from a bacterium of the phylum Bacteroidetes, with homologues in various bacteria, typically organized in a conserved uncharacterized putative operon. Sequence analyses of the six proteins encoded by the operon yielded the following annotation for them: (i) a novel family without discernible homologues; (ii) a new family within the superfamily of metallo-dependent hydrolases; (iii) a novel subgroup of the UbiA superfamily of prenyl transferases; (iv) a new clade within the sugar phosphate cyclase superfamily; (v) a new family within the xylose isomerase-like superfamily; and (vi) a hydrolase for a phosphate moietycontaining substrate. We suggest that the operon encodes enzymes of a pathway synthesizing an isoprenoid-cyclitol-derived compound, possibly an antimicrobial or other protective substance. To the best of our knowledge, this is the first report of an expansion of the metabolic capacity of a plastid mediated by HGT into the plastid genome.
Permanent Link: http://hdl.handle.net/11104/0270188