SMALL is beautiful in more ways than one for the ocean-dwelling bacterium Pelagibacter. As well as being among the tiniest of all bacteria, it has now been identified as having the most streamlined genome so far found in a free-living organism.
It contains just 1354 genes scattered over 1.3 million DNA base pairs and is almost entirely devoid of “junk” DNA, according to researchers at Oregon State University in Corvallis (Science, vol 309, p 1242).
This streamlining could mean the bacterium needs less nitrogen and phosphorus to copy itself, allowing it to grow where nutrients are scarce. This…
