Kup and KimA: two secondary transporters involved in the homeostasis of K+ in Enterococcus faecalis

ACCIARRI, GIULIANA; ESPARIZ, MARTIN; BLANCATO, VÍCTOR S.; MAGNI, CHRISTIAN

Paraná

Congreso; LIV Reunión Anual de SAIB; 2018

SAIB

The E. faecalis species challenges the boundary between commensal and pathogen. Despite its controversial profile, they are part of food products. Besides, ion homeostasis is a key factor for all living cells. Potassium (K+) is important for several basic physiological functions. A search for genes present in E. faecalis genome coding for proteins with high homology for K+ transporters and a subsequent topology analysis, revealed the presence of a Kup as well as a KimA homologue. These proteins are regulated by the secondary messenger c-di-AMP in L. lactis and B. subtilis, respectively. To study the functional properties of the proteins encoded by both genes we used E. coli LB650, a triple mutant for the main K+ transporter systems. E. faecalis JH2-2 kup gene was individually cloned in plasmid pWH844 using E. coli LB650 as host, to check if its expression could restore growth in minimal salt media when no KCl is added. Kup evidence growth with or without K+ supplementation. These results suggest that Kup and KimA are involved in the K+ transport in E. faecalis.