The research aims at finding out the distinctive lines of energetics in
natronophilic microorganisms started to be described (Banciu & Muntyan,
2015). Among used methods were analyses of respiratory characteristics,
electrical potential generation, pH changes in cells/vesicle
...
The research aims at finding out the distinctive lines of energetics in
natronophilic microorganisms started to be described (Banciu & Muntyan,
2015). Among used methods were analyses of respiratory characteristics,
electrical potential generation, pH changes in cells/vesicles suspension upon
light/oxygen impulses, effects of ionophores and uncouplers, visualization of
sodium transport using radioisotope 22Na, phylogenetics. Summary of results:
So far, a novel type of primary energy transformer, Na+‐motive cytochrome
oxidase, which has been proven to operate in natronophilic strains of the
genus Thioalkalivibrio (Muntyan et al., 2015), has been discovered, and then
found in several other extremophiles. It has been demonstrated that in these
same strains, cell motility is provided by Na+‐motive flagella. In addition, it
was shown that the rhodopsin‐like pigment, proteorhodopsin, in the new
natronophilic strain of a novel deep‐lineage of the phylum Balneolaeota,
Cyclonatronum proteinivorum, pumps Na+ from cells (Sorokin et al., 2018). The
screening of Na+‐motive energy mechanisms revealed the sodium energy
cycle, consisting of (i) primary mechanisms for generating Na+‐potential and
(ii) Na+‐potential consumers, represented by flagella and FoF1‐ATPase.
Conclusion: Along the way, we first discovered that several species of bacteria
simultaneously have in their genomes: (i) oxygen‐consuming generators of
Na+‐potential (Na+‐pumping cbb3 oxidases) and (ii) consumers of Na+‐
potential such as Na+‐ATPase of F0F1‐type and flagella. Thus, for the first time,
it became possible to establish the presence of a complete Na+‐cycle in
energetics of oxygen‐respiring bacteria.@en
