The complete chloroplast DNA sequence of the green alga Oltmannsiellopsis viridis reveals a distinctive quadripartite architecture in the chloroplast genome of early diverging ulvophytes

Table 1 General features of Oltmannsiellopsis and other chlorophyte cpDNAs

Feature	Nephroselmis	Chlorella	Oltmannsiellopsis	Pseudendoclonium	Chlamydomonas
Size (bp)
Total	200,799	150,613	151,933	195,867	203,827
IR	46,137	--^a	18,510	6,039	22,211
LSC	92,126	--^a	33,610	140,914	81,307^b
SSC	16,399	--^a	81,303	42,875	78,088^b
A+T (%)	57.9	68.4	59.5	68.5	65.5
Coding sequences (%)^c	68.7	60.9	59.2	62.3	50.1
Genes (no.)^d	128	112	105	105	94
Introns (no.)
Group I	0	3	5	27	5
Group II	0	0	0	0	2

^a Because Chlorella cpDNA lacks an IR, only the total size of this genome is given.
^b The LSC and SSC regions of Chlamydomonas cpDNA cannot be distinguished unambiguously.
^c Conserved genes, unique ORFs and introns were considered as coding sequences.
^d Genes present in the IR were counted only once. Unique ORFs and intron ORFs were not taken into account.

ISSN: 1741-7007