In recent years, people usually associate a term “virus” with either a computer bug or with flu. What do you think of viruses? Will you be surprised to know that bacteriophages, viruses that specifically infect bacteria, are the most abundant biological entities in the biosphere? That the global estimation of phages encounters more than trillion of trillions individuals everywhere around us? It is astonishing, isn’t it?
My research is focused on one of tailed phages—enterobacteria phage phi-80—which belongs to the Siphoviridae family of double-stranded DNA viruses. Phages are mostly obligate itracellular parasites. Phi-80 takes over copy machinery of Escherichia coli bacteria, the most studied organism in the World, in order to reproduce itself. To attach and infect an E. coli cell, it specifically binds to the outer membrane (OM) TonB-dependent transporter (TBDT) protein FhuA (see Fig. 1), responsible for iron uptake inside the cell.
Fig. 1. TonB-gated outer membrane receptor transporter protein FhuA. The figure illustrates ExbB/D—TonB—FhuA iron transport system of E. coli. FhuA represents a betta-barrel outer membrane transport protein, which is driven by proton motive force harvested by the inner membrane ExbB/D protein complex and transduced by TonB protein to FhuA.