Sex in dus

This suggests that DUSs are implicated in genome stability rather than in generating adaptive variation.DUS elements are most frequent in the permissive locations of the core genome but are themselves highly conserved, undergoing mutation selection balance and/or molecular drive.This is because it re-assorts genetic information among members of the same species and, contrary to transduction and conjugation, is a process under the direct control of the recipient cell [].

It is present in approximately 2,000 copies occupying 1% of the sequenced neisserial genomes, which is much more than expected given the sizes of the genomes and their composition, and can only be maintained by strong counteraction to drift [] and is the one considered in this study.

However, because 75% of 10-nucleotide DUSs also are also extended 12-nucleotide DUSs, this should not affect our conclusions.

Competent bacteria have invested extensively in complex machineries to facilitate transformation, involving a comprehensive range of competence and recombination proteins [].

Given the role of HGT in genome fluidity, elucidation of the evolutionary role of natural transformation is pivotal to our understanding of prokaryotic adaptation.

However, recent studies have demonstrated that these processes, at least in ] and the term 'transformation complex' has been coined.

DNA has, per definition, been taken up when it is no longer degradable by DNase, but more research is needed to appreciate fully the physical implications of the DNase protected state and exactly where DUS specificity acts.

The mechanism of preferential DNA uptake may also be involved in DUS/USS fixation by classic natural selection driven by the advantage of taking up conspecific DUS-containing DNA or preventing the entry of alien sequences.

The darwinian model generally seeks the potential selective advantages of sex and particularly 'safe sex', whereas the molecular drive model seeks to explain how these genomes can tolerate such large amounts of an 'intrusive' repetitive sequence without discretion, and in essence how DUSs/USSs can accumulate without being positively selected for by forces affecting the fitness of the organism.

If the DNA uptake machinery by some physical means has a preference for DUSs, then sequences containing a DUS are more likely to be transferred and, consequently, effectively accumulate in the genomes of .

Tags: , ,