by Merry Youle
Roseovarius nubinhibens recently joined the exclusive club of about a thousand bacteria whose genomes have been sequenced. Why this honor? It’s a member of one of the most ubiquitous and most intensely studied cl
by Merry Youle
Roseovarius nubinhibens recently joined the exclusive club of about a thousand bacteria whose genomes have been sequenced. Why this honor? It’s a member of one of the most ubiquitous and most intensely studied clades of α-Proteobacteria, the marine roseobacters. This populous group participates in important jobs, including the global cycling of sulfur, climate regulation, and even modulation of our day-to-day weather. (For the latter, see our earlier post.) To appreciate the sulfuric importance of R. nubinhibens in particular, we need to begin with the major quantities of dimethylsulfoniopropionate (DMSP) made by marine algae for whom it serves as an osmolyte. Roseobacters then enter the picture, their work being to break down the DMSP by either of two pathways. One route converts DMSP into volatile DMS that can give rise to sulfate aerosols that act as cloud seeds. The other pathway leads to methanethiol, a primary sulfur source for marine bacteria. The relative amount of sulfur that flows each direction matters. R. nubinhibens was one of the first bacteria found to be able to carry out both conversions, thus is a potentially important switch point. The researchers reporting its isolation (José González and colleagues in Mary Ann Moran's lab) dubbed their new species Roseovarius nubinhibens (from the Latin nubes, for clouds, and inhibens, for inhibiting).
Virus-like particles generated by mitomycin C induction of R. nubinhibens
ISM. Siphovirus particles are commonly seen in the induced lysate, and
many of them appear to be “empty.” Bars = 50 nm. Source.
The R. nubinhibens genome has been sequenced. Any prophages on board? A routine search using Prophage Finder (software th