Alkaliphile-specific motif analysis of Stenotrophomonas species DL18 F1Fo-ATP synthase c-subunit isolated from Indian alkaline Soda Lake, Lonar

The membrane-associated F1Fo-ATP synthase of bacteria plays a vital role in the production of energy molecule, i.e. adenosine triphosphate (ATP). However, under alkaline conditions, ATP synthesis in bacteria is not thermodynamically feasible due to external high pH. Various studies reported motifs in ATP synthase c-subunit as alkaliphile-specific features for adaptation under alkaline condition. Some conserved residues in alkaliphiles were observed in Stenotrophomonas species DL18 isolated from Indian alkaline Soda Lake, Lonar, which has pH 10.5. The above-mentioned specific amino acid features in the studied alkaliphile may involve proton translocating mechanism for ATP synthesis. The studied motifs of F1Fo-ATP synthase c-subunit of Stenotrophomonas species DL18 have GXGXGXA in the inner helix and GXXDXXF in the outer helix. The overall interacting residues of the c-subunit structure may be responsible for the ATP synthesis in particular pH conditions.