A Long-Branch Attraction Artifact Reveals an Adaptive Radiation in Pseudomonas

作者：Bodilis Josselin^*; Meilo Sandrine Nsigue; Cornelis Pierre; De Vos Paul; Barray Sylvie

来源：Molecular Biology and Evolution, 2011, 28(10): 2723-2726.

DOI：10.1093/molbev/msr099

• molecular phylogeny
• incongruence
• Pseudomonas
• oprF
• long-branch attraction
• adaptive radiation

A significant proportion of protein-encoding gene phylogenies in bacteria is inconsistent with the species phylogeny. It was usually argued that such inconsistencies resulted from lateral transfers. Here, by further studying the phylogeny of the oprF gene encoding the major surface protein in the bacterial Pseudomonas genus, we found that the incongruent tree topology observed results from a long-branch attraction (LBA) artifact and not from lateral transfers. LBA in the oprF phylogeny could be explained by the faster evolution in a lineage adapted to the rhizosphere, highlighting an unexpected adaptive radiation. We argue that analysis of such artifacts in other inconsistent bacterial phylogenies could be a valuable tool in molecular ecology to highlight cryptic adaptive radiations in microorganisms.

• 出版日期2011-10