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SO ENDS this first weekend review of new thinking about the old concept of one pathogen one disease; there are some today who advocate an ecological viewpoint, where a web of interacting microorganisms cause a disease progression, and this has considerable biological support. The implications of this new thinking are profound. View in LinkedIn

WEB OF INTERACTIONS. “In addition, microorganisms interact with each other. Antagonistic and mutualistic behaviors have evolved as adaptations to living in microbial communities.” https://lnkd.in/gEfVGaC View in LinkedIn

PATHOGEN SELECTION PRESSURES. “ The ecosystems within which pathogens evolve are defined by their abiotic and biotic dimensions, including both host and vector populations. Pathogens must adapt to selective pressures associated with these complex ecosystems, in particular to both host and vector defense mechanisms as well as to any environmental fluctuations impacting on their survival and/or dispersal outside of hosts or vectors.” https://lnkd.in/gEfVGaC View in LinkedIn

SNAPSHOT OF EVOLUTION. “The third goal is to understand the impact of microbial communities on the persistence, transmission, and evolution of pathogens. In particular, to elucidate the spatio-temporal dynamics of these communities, the ecological interactions between microorganisms within communities, as well as the evolutionary forces at play (mutation, selection and gene flow)—especially when it comes to pathogen survival, extinction or dispersal.” https://lnkd.in/gEfVGaC View in LinkedIn

SEX CHROMOSOME DIVERSITY. "We identify over a dozen different sex chromosome configurations, and the small dot chromosome is repeatedly used as the sex chromosome, which presumably reflects the ancestral karyotype of higher Diptera." (Winged insects). https://lnkd.in/dX2rADH View in LinkedIn

MISSING THE DYNAMIC PICTURE. “Because metagenomic DNA-based analyses cannot differentiate between expressed and non-expressed genes, these approaches fail to reflect the actual activity or dynamics of microbial communities.” https://lnkd.in/gEfVGaC View in LinkedIn

FORK IN THE ROAD. "Sex chromosomes that show low levels of differentiation are generally considered to be evolutionarily young and only at the initial stages of this path; given time, they too are expected to differentiate." http://www.pnas.org/content/110/16/6453.full View in LinkedIn

FROM SOIL TO CLINIC. “The most recent evidence for the transfer of antibiotic resistance genes between the environment and the clinic is provided by Forsberg et al. (2012). Using an innovating metagenomic approach, the authors identified DNA sequences in cultured multi-drug-resistant soil Proteobacteria which had 100% identity to resistance genes found in clinical pathogens, including resistance against β-lactams, tetracyclines, aminoglycosides, sulfonamides, and chloramphenicol.” https://lnkd.in/gEfVGaC View in LinkedIn

HETEROMORPHIC IDENTITY. "Restriction of recombination across the entire length of the sex chromosomes and continuous gene decay on the Y results in heteromorphism between the X and Y (or Z and W)." http://www.pnas.org/content/110/16/6453.full View in LinkedIn

HORIZONTAL GENE TRANSMISSION. “The spreading of antibiotic resistance genes is another example of the vital importance of the microbial context, as pathogens may be able to acquire resistance phenotypes from environmental reservoirs.” https://lnkd.in/gEfVGaC View in LinkedIn