In the late 1930s American botanist Herbert F. Copeland proposed a separate kingdom for the bacteria (kingdom Monera), based on their unique absence of a clearly defined nucleus.
Although the unique absence of a well-conserved homologue of Omp85 from the OM of Chlorobacteria is strong evidence that they are the most ancient negibacteria, it does not by itself prove that they are the most ancient eubacteria of all.
Though the unique absence of the tritocerebral appendages in insects and myriapods is a long discussed common feature of these two arthropod classes, it was often considered as a mere convergence and not as a synapomorphy (e.g. [ 13, 24- 26]).
The unique absence of CD4+ NKT lymphocytes in sooty mangabeys, combined with their IL-10 cytokine-secreting ability and preservation following SIV infection, raises the possibility that NKT lymphocytes might play a role in downmodulating immune activation in SIV-infected sooty mangabeys.
To verify the unique presence of TCS-18 in S. ratti, the unique absence of TCS-13 in S. ratti, and the unique absence of TCS-9 as well as TCS-3 in S. sobrinus, PCR amplification using original DNA from strains S. mutans UA159, S. ratti DSM20564, and S. sobrinus DSM20742 was performed.
In particular, the unique absence of enzyme classes for plant cell wall degradation and maintenance of enzymes that break down components of pollen tubes and flowers provides a striking example of biotrophic host adaptation.
The unique absence of enzyme classes for plant cell wall degradation and maintenance of enzymes that break down components of pollen tubes and flowers provides a striking example of biotrophic host adaptation.
On the other hand, some other features, such as the presence of duplicated ppgk genes and the unique absence of one type of ppx gene, were specific to the M. phosphovorus genome.
Our analysis also confirms the unique absence of members of the widely conserved STE group, named after sterility phenotypes in yeast, which in other eukaryotes have critical functions, i.e., as upstream activators of mitogen-activated protein (MAP) kinases, two homologs of which are present in Plasmodium (Dorin-Semblat et al., 2007).
Most of the unique absences in UGA10 represented hypothetical and putatively phage-derived genes located in HGIb in the Houston-1 genome.
