In the ryegrass-maize sequence uptakes were as high as 336 kg N ha−1 year−1.
Among these, Pasteurellaceae and Neisseriaceae species preferentially take up DNA containing specific short sequences, called uptake signal sequences (USS) and DNA uptake sequences (DUS), respectively [3] [9].
It has been shown that Pasteurellaceae species preferentially take up short DNA sequences, called uptake signal sequences (USS), that are overrepresented in their respective genomes [41].
A recent bioinformatics study suggest that at least for some classes of short DNA sequences, DNA uptake is biased by sequence definition, which is not necessarily consistent with nutrient driven uptake [33].
In coding sequences, accumulation of uptake sequences is expected to affect the outcome of natural selection on protein function.
These sequences are known as DNA uptake sequence (DUS) and uptake signal sequence (USS).
In the absence of sequence-specific uptake, which has not been demonstrated, the transfer of foreign RNA molecules should mirror their distribution and abundance in the source material.
Uptake sequences are called uptake signal sequences (USSs) and DNA uptake sequences (DUSs) in the Pasteurellaceae and Neisseria, respectively (Smith et al. 1995, 1999; Ambur et al. 2007); in this paper, we will use "USSs" and "DUSs" when describing the uptake sequences specific to each group and "uptake sequences" or "USs" when discussing general properties of all uptake sequences.
Sequences with a single mismatch to the uptake sequence consensus provide the pool from which the perfect uptake sequences arise; they are overrepresented in genomes and preferred by uptake machinery over nonuptake sequences, though less so than perfect matches (Bakkali et al. 2004).
In all three genomes, uptake sequence accumulation in coding sequences has approximately doubled the frequencies of those tripeptides specified by each species' uptake sequence.
