Here\u2019s what you\u2019ll learn when you read this story:<\/p>\n
Viruses typically aren\u2019t considered \u2018alive,\u2019 as many core biological functions are outsourced to their potential hosts. But a newly discovered organism appears to straddle the line between virus and cell.<\/p>\n
Like a virus, this new organism \u2018Sukunaarchaeum mirabile\u2019 outsources some functions to its potential host, but can still create its own ribosomes and RNA.<\/p>\n
Its genome is also surprisingly small, and is roughly half the size (238,000 base pairs) of the next-smallest archaeal genome.<\/p>\n
At first glance, creating a definition for \u201clife<\/a>\u201d seems somewhat straightforward. Sentient animals all the way down to single-celled organisms capable of reproduction are welcome on the tree of life, but there are other organisms that challenge this understanding, like viruses. Because virus don\u2019t grow, reproduce on their own, or make their own energy, they\u2019re typically excluded from definitions of life.<\/p>\n But once a virus infects a potential host, it\u2019s immensely active, and can be responsible for world-altering events (see: Spanish flu, ebola, COVID-19, and so on).<\/p>\n However, life is complicated, and this controversial categorization of \u201clife\u201d and \u201cnot life\u201d can have gray areas in which organisms<\/a> appear to defy the expectations of both camps. Recently, scientists found a new creature perched right on the edge of the \u201clife\u201d category.<\/p>\n In a paper published on the bioRxiv<\/a> server, researchers in Canada and Japan outlined how they identified a new cellular entity that appeared to challenge aspects of the typical definitions of cellular life.<\/p>\n Currently named \u2018Sukunaarchaeum mirabile\u2019 (after a deity in Japanese mythology known for its small stature), this entity\u2014which the research team has concluded is a form of life\u2014contains the necessary genes to create its own ribosomes and messenger RNA<\/a>, something your typical virus lacks. But like a virus, it offloads certain biological functions onto its potential host and it appears singularly obsessed with replicating itself.<\/p>\n \u201cIts genome is profoundly stripped-down, lacking virtually all recognizable metabolic pathways, and primarily encoding the machinery for its replicative core: DNA<\/a> replication, transcription, and translation,\u201d the authors wrote. \u201cThis suggests an unprecedented level of metabolic dependence on a host, a condition that challenges the functional distinctions between minimal cellular life and viruses.\u201d<\/p>\n Led by Ryo Harada, a molecular biologist from Dalhousie University in Halifax, Nova Scotia, the team chanced upon this strange creature while studying the bacterial genome of the marine plankton Citharistes regius. Within the genomic data, Harada and his team found a loop of DNA that didn\u2019t match with any known species. They eventually determined that the organism belonged to the domain Archaea\u2014a group associated with prokaryotic cells<\/a>, but from which eukaryotic cells (i.e. you and me) ultimately descended a couple billion years ago.<\/p>\n Perhaps the most remarkable feature of Sukunaarchaeum is its extreme genome reduction, with only 238,000 base pairs of DNA. Viruses, as Live Science points out, can contain many hundreds of thousands more base pairs, and can even reach up into the millions. As for fellow archaea, the smallest known complete genome<\/a> within this group stretches to 490,000 base pairs, meaning that Sukunaarchaeum contains less than half the number of base pairs posessed by even the smallest archaeal genome.<\/p>\n \u201cThe discovery of Sukunaarchaeum pushes the conventional boundaries of cellular life and highlights the vast unexplored biological novelty within microbial interactions,\u201d the authors wrote. \u201cFurther exploration of symbiotic systems may reveal even more extraordinary life forms, reshaping our understanding of cellular evolution<\/a>.\u201d<\/p>\n You Might Also Like<\/p>\n","protected":false},"excerpt":{"rendered":"Here\u2019s what you\u2019ll learn when you read this story: Viruses typically aren\u2019t considered \u2018alive,\u2019 as many core biological…\n","protected":false},"author":2,"featured_media":186185,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[107719,107718,85,46,141,107720,386],"class_list":{"0":"post-186184","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-wildlife","8":"tag-base-pairs","9":"tag-biological-functions","10":"tag-il","11":"tag-israel","12":"tag-science","13":"tag-typical-definitions","14":"tag-wildlife"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/186184","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=186184"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/186184\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/186185"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=186184"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=186184"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=186184"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}