http://precedings.nature.com/tags/Metagenomics Recently posted documents tagged with 'Metagenomics' Nature Publishing Group en Nature Precedings http://precedings.nature.com/images/header_logo.gif http://precedings.nature.com http://dx.doi.org/10.1038/npre.2009.3489.1 The remarkable diversity of genes within the pool of prokaryotic genomes belonging to the same species or pan-genome is difficult to reconcile with the widely accepted paradigm which asserts that periodic selection within bacterial populations would regularly purge genomic diversity by clonal replacement. Recent evidence from metagenomics indicates that even within a single sample a large diversity of genomes can be present for a single species. We have found that much of the differential gene content affects regions that are potential phage recognition targets. We therefore propose the operation of Constant-Diversity dynamics in which the diversity of prokaryotic populations is preserved by phage predation. We provide supporting evidence for this model from metagenomics, mathematical analysis and computer simulations. Periodic selection and phage predation dynamics are not mutually exclusive; we compare their predictions to indicate under which ecological circumstances each dynamics could predominate. http://dx.doi.org/10.1038/npre.2009.3489.1 Wed, 29 Jul 2009 18:18:35 UTC Explaining microbial population genomics through phage predation doi:10.1038/npre.2009.3489.1 2009-07-29 Francisco Rodriguez-Valera Nature Precedings 2009-07-29T18:18:35Z Manuscript Microbiology http://creativecommons.org/licenses/by/3.0/ http://dx.doi.org/10.1038/npre.2007.164.1 The US CDC believes that 65% of all infections in developed countries may be caused by pathogens in biofilms. Electron Microscopy has shown that these bacterial communities can evade phagocytosis, and persist in the cytoplasm of monocytes, macrophages, lymphocytes and neutrophils. Three decades ago, Wirostko et al. found such intraphagocytic communities in Crohn’s disease, Juvenile Rheumatoid Arthritis and Sarcoidosis. However, the mechanism(s) by which such persistent bacteria could evade the immune system have remained elusive. Recently, 16S RNA from species of gliding bacteria never thought to be able to survive in vivo, have been found in surgically removed biofilms. This study set out to identify whether the genomes of these gliding bacteria might yield insight into mechanisms by which such persistent pathogens could evade phagocytosis. http://dx.doi.org/10.1038/npre.2007.164.1 Fri, 22 Jun 2007 13:17:53 UTC Bacterial Capnine Blocks Transcription of Human Antimicrobial Peptides doi:10.1038/npre.2007.164.1 2007-06-22 Trevor G. Marshall Nature Precedings 2007-06-22T13:17:53Z Poster Immunology Microbiology Bioinformatics http://creativecommons.org/licenses/by/2.5/