Nuclear reaction
Saturday, November 22nd, 2014Nuclear reaction
http://www.economist.com/news/science-and-technology/21630959-how-complex-cells-evolved-mystery-new-idea-may-come-close Hypothesis from BMC paper on #evolution of eukaryotes from membrane blebs (http://www.biomedcentral.com/1741-7007/12/76)
An inside-out origin for the eukaryotic cell
David A Baum and Buzz Baum
BMC Biology 2014, 12:76 doi:10.1186/s12915-014-0076-2
QT:{{”
The consensus is that the first eukaryote was a prokaryote which engulfed, but failed on several occasions to digest, other
prokaryotes. One of these undigested meals was a bacterium ancestral to mitochondria. Even today mitochondria have their own genes separate from those in the nucleus. These genes, which are carried on circular DNA molecules like those in bacteria, resemble those in a group of bacteria called Rickettsiales,
…
They imagine the original host prokaryote creating small protrusions, known to microbiologists as blebs, that poked out of it, as the diagram shows, like tiny fingers. Blebs like this are known to form in certain sorts of archaea, a group of prokaryotes distinct from bacteria proper that biochemical evidence suggests were involved in the formation of eukaryotes. The job of blebs is unclear, as archaea are not a well-studied group, but they may be feeding structures. The Drs Baum suggest that, in the case of the ancestral eukaryote, the blebs grew bigger and bigger, pinning proto-mitochondria (and, on a subsequent occasion, proto-chloroplasts), into the intervening spaces. “}}