Draft Genome Sequence of the Cyanobacterium sp. Strain Nb3U1.

We report the 3.5-Mb draft genome sequence of the cyanobacterium sp. strain Nb3U1, which was isolated from a microbial mat sample collected from Nakabusa Hot Spring, Nagano, Japan.

Unraveling the role of the enigmatic MatK maturase in chloroplast group IIA intron excision.

Maturases are prokaryotic enzymes that aid self-excision of introns in precursor RNAs and have evolutionary ties to the nuclear spliceosome. Both the mitochondria and chloroplast, due to their prokaryotic origin, encode a single intron maturase, MatR for the mitochondria and MatK for the chloroplast. MatK is proposed to aid excision of seven different chloroplast group IIA introns that reside within precursor RNAs for essential elements of chloroplast function.