Category: Uncategorized

NON-REPRODUCTIVE GENE SHARING. “Horizontal gene transfer can lead to the profound phenotypic change from benign commensal to lethal pathogen. “Horizontal” in this context refers to the lateral or “sideways” movement of genes between microbes via mechanisms not directly associated with reproduction.” Normally, gene sharing in other kingdoms is exclusively about reproduction. https://lnkd.in/ewnQ9Vg View in LinkedIn

DAZZLING AVATARS REVEALED. “Being intractable to research, prokaryotic life became a kind of biological dark matter—life forms known to be present and abundant, but whose properties and behavior could not be assessed. The analogy to cosmological dark matter is obvious. Now, the emergence of metagenomic analytical methods has rendered visible this heretofore hidden half of the biosphere—at least as genomic avatars. The results are dazzling.” https://standardsingenomics.biomedcentral.com/articles/10.1186/s40793-016-0180-8 View in LinkedIn

STRAIN GENE VARIATION. ““As the numbers of sequenced E. coli strains continues to grow, the number of discovered core genes remains about the same, while the number of flex genes grows linearly with the number of strains sequenced. Land et al., asserted that comparison of more than 2000 Escherichia coli genomes finds an E. coli core genome of about 3100 gene families and a total of about 89,000 gene families.” https://standardsingenomics.biomedcentral.com/articles/10.1186/s40793-016-0180-8 View in LinkedIn

INVISIBLE UNCULTURABLES. “Historically, far more cells have been seen by direct observation than could not be enticed to develop into colonies. Measurements of the ratio of culturable to actual cells range from 10(-2) to 10(-8), indicating that the vast majority of environmental prokaryotic cells cannot be studied in the laboratory, rendering them—until now—effectively invisible to science.” https://lnkd.in/ewnQ9Vg View in LinkedIn

DOUBTFUL SPECIES UTILITY. “By comparison, current data suggest a 30 % overlap in gene content between humans and mice. That is, there may be more genetic similarity between a randomly selected human and a randomly selected mouse than there is between two bacterial cells of the same “species.” Clearly, a species concept that encompasses that much genetic variation is not compatible with the species concept as generally applied to multi-cellular eukaryotes.” https://standardsingenomics.biomedcentral.com/articles/10.1186/s40793-016-0180-8 View in LinkedIn

HERETICS FIRST. “Not surprisingly, Woese’s work was originally doubted, even ridiculed, by many biologists. One referred to him as “a crank, who was using a crazy technique to answer an impossible question”. Subsequent improvements in sequencing technology, however, allowed the confirmation of a three-domain biosphere, of which the two prokaryotic realms are essentially alien to classical biology. Now, the three-domain view is well established, even at the level of introductory textbooks.” https://standardsingenomics.biomedcentral.com/articles/10.1186/s40793-016-0180-8 View in LinkedIn

STRAINS VERSUS SPECIES. “This is a stunning amount of variation within one “species” of bacteria. (Strains in the genus Shigella are now regarded as E. coli variants that need reclassification). If only strains currently named E. coli are considered, the number of core gene families rises from 993 to 1472, a slight increase of 6 % to 9 % of the total pan-genome.” https://standardsingenomics.biomedcentral.com/articles/10.1186/s40793-016-0180-8 View in LinkedIn

TUMOR-LIKE GENOMES. “In many cases, a typical individual bacterial cell carries less than 50 % of the genes found in the species’ pan-genome—a level of genomic plasticity that in multi-cellular eukaryotes is only seen in highly unregulated tumors.” https://standardsingenomics.biomedcentral.com/articles/10.1186/s40793-016-0180-8 View in LinkedIn

ORIFICE CONTROL. “The muscles of facial expression are arranged around the orifices of the face (orbita, mouth and nose). Their function is thus to control these orifices as sphincters and dilators.” https://lnkd.in/dG53As2 View in LinkedIn

FACIAL MUSCLES. “The human face has the greatest mobility and facial display repertoire among all primates. However, the variables that account for this are not clear. Humans and other anthropoids have remarkably similar mimetic musculature. This suggests that differences among the mimetic muscles alone may not account for the increased mobility and facial display repertoire seen in humans.” https://lnkd.in/di-WAXE View in LinkedIn