Molecular biology and evolution of the bacterial intranuclear parasite Ca. Endonucleobacter

Few bacteria are able to colonize eukaryotic host cells, and even fewer can
invade organelles. Among the latter, those which colonize the nucleus
(intranuclear bacteria) are a majority. The nucleus is considered as a
replication niche that offers bacteria shelter, the opportunity to manipulate
nuclear processes and nutrients in form of chromatin. Previous studies have
suggested that intranuclear bacteria consume host chromatin, but this would
inevitably lead to a collapse of their replication niche. Nuclear colonization
has intrinsic risks for bacteria, as eukaryotic cells are able to sense nuclear
deformation and respond to it activating apoptosis. Therefore, intranuclear
bacteria must count on molecular mechanisms to prevent their host cells to
shut down. Although many intranuclear bacteria have been visually
characterized, little is known about how they colonize the nucleus, how they
thrive within, and which effects they have on their host cells. [...] My findings
challenge previous hypotheses about nutritional and survival strategies of
intranuclear bacteria, and point out the genomic innovations that might
define intranuclear lifestyle in bacteria.