title: Analysis of the complete plastid genome of the unicellular red alga Porphyridium purpureum.
abstract: We determined the complete nucleotide sequence of the plastid genome of the unicellular marine red alga Porphyridium purpureum strain NIES 2140, belonging to the unsequenced class Porphyridiophyceae. The genome is a circular DNA composed of 217,694 bp with the GC content of 30.3%. Twenty-nine of the 224 protein-coding genes contain one or multiple intron(s). A group I intron was found in the rpl28 gene, whereas the other introns were group II introns. The P. purpureum plastid genome has one non-coding RNA (ncRNA) gene, 29 tRNA genes and two nonidentical ribosomal RNA operons. One rRNA operon has a tRNA(Ala)(UGC) gene between the rrs and the rrl genes, whereas another has a tRNA(Ile)(GAU) gene. Phylogenetic analyses suggest that the plastids of Heterokontophyta, Cryptophyta and Haptophyta originated from the subphylum Rhodophytina. The order of the genes in the ribosomal protein cluster of the P. purpureum plastid genome differs from that of other Rhodophyta and Chromalveolata. These results suggest that a large-scale rearrangement occurred in the plastid genome of P. purpureum after its separation from other Rhodophyta.
authors.affiliation: Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo, 153-8902, Japan, naoT507@bio.c.u-tokyo.ac.jp.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Tajima
authors.forename: Shusei
authors.initials: S
authors.lastname: Sato
authors.forename: Fumito
authors.initials: F
authors.lastname: Maruyama
authors.forename: Ken
authors.initials: K
authors.lastname: Kurokawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ohta
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tabata
authors.forename: Kohsuke
authors.initials: K
authors.lastname: Sekine
authors.forename: Takashi
authors.initials: T
authors.lastname: Moriyama
authors.forename: Naoki
authors.initials: N
authors.lastname: Sato
mesh_terms: D000926:Anticodon / Q000235:genetics; D017343:Genes, Plant / Q000235:genetics; D054627:Genome, Plastid / Q000235:genetics*; D007438:Introns / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family; D016366:Open Reading Frames / Q000235:genetics; D010802:Phylogeny; D044665:Porphyridium / Q000235:genetics*; D012343:RNA, Transfer / Q000235:genetics; D012269:Ribosomal Proteins / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D000926:Anticodon; D012269:Ribosomal Proteins; D012343:RNA, Transfer