Category: Uncategorized

FROM SYMBIOSIS TO ORGANELLE. "Reductive evolution of endosymbionts can yield bacteria with tiny genomes consisting of 150–200 genes and lacking some essential genes such as those encoding several aminoacyl-tRNA synthetases, which is suggestive of an ongoing transition to an organelle state." A snapshot in real time of how mitochondria and chloroplasts evolved. https://lnkd.in/egqWFZp View in LinkedIn

BIG TICKET REDUCTIONS. "The mitochondria, the ubiquitous energy-transforming organelles of eukaryotes, and the chloroplasts, the organelles responsible for the eukaryotic photosynthesis, are the ultimate realizations of bacterial reductive evolution." Massive gene loses. https://lnkd.in/egqWFZp View in LinkedIn

ADVANTAGE. "Gene loss can provide a selective advantage by conserving an organism’s limiting resources, provided the gene’s function is dispensable." http://mbio.asm.org/content/3/2/e00036-12.short View in LinkedIn

EUKARYOTE GENES. "The reconstructions consistently indicate that ancestral eukaryotes including...the founders of each supergroup were intron-rich forms, with intron densities higher than those in the genes of most extant eukaryotes and probably only slightly lower than those in the modern organisms with the most complex gene structures, such as mammals." https://lnkd.in/egqWFZp View in LinkedIn

COMMON BACTERIAL REDUCTION. "Reductive genomic evolution, driven by genetic drift, is common in endosymbiotic bacteria." https://lnkd.in/e9TnyEE View in LinkedIn

ANCIENT REDUCTIONS. "The most compelling evidence of the dominance of genome reduction and simplification was obtained through the reconstruction of the genomic evolution of archaea that almost exclusively are free-living organisms." https://lnkd.in/egqWFZp View in LinkedIn

SECONDARY GAINS. "The reductive trend is countered by proliferation of genes involved in parasite-host interaction such as, for example, ankyrin repeat proteins that act as secreted virulence factors." https://lnkd.in/egqWFZp View in LinkedIn

REDUCTION CONSTRAINTS. "The evolution of the genomes of parasites, symbionts and commensals is not a one-way path of reduction. On the contrary, the reduction ratchet is constrained by the advantages of retaining certain metabolic pathways that complement the host metabolism." https://lnkd.in/egqWFZp View in LinkedIn

COMMENSALS. "Beyond parasites and symbionts, reductive evolution was observed in several groups of organisms that evolved a commensal life style. One of the best-characterized cases involves the Lactobacillales, a group of Gram-positive bacteria that is extremely common in a variety of animal- and plant-associated habitats...substantial gene loss, from ∼3,000 genes in the common ancestor of Bacilli to ∼1,300–1,800 genes in various Lactobacilli species." https://lnkd.in/egqWFZp View in LinkedIn

VAST NUMBERS. "Viruses are the most abundant ‘life forms’ in aquatic systems, and their number probably exceeds 10(29) in the ocean. Aligning these oceanic viruses and assuming an average diameter of 50 nm for a marine virus, the viral string-of-pearls would be 400,000 light years long. In comparison, the diameter of our galaxy, the Milky Way, is only 25,000 light years." http://onlinelibrary.wiley.com/doi/10.1046/j.1462-2920.2003.00539.x/full View in LinkedIn