Functional characterization of the cell division protein ftsa of Streptococcus pneumoniae

NUBIA YANDAR; NICOLAS REINOSO; PAULO CORTES; JOSE ECHENIQUE

Cordoba

Encuentro; LII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2016

SAIB

FtsA is a divisome protein that connects the master coordinator of cell division, FtsZ, to the cell membrane for tethering the Z-ring andseptal formation. Previous reports have showed that FtsA forms a ring-like structure at the division site of streptococcal cells. Inaddition, some authors reported that ftsA is an essential gene. In this work, we could obtain the ftsA mutant by insertion mutagenesisdemonstrating that ftsA is dispensable for cell viability. However, the ftsA mutant displayed fitness and morphological alterations. Byfluorescence microscopy, we also found a delocalization of FtsZ-GFP in the ftsA mutant, phenotype that is compatible with the knownFtsA function. The wild-type shape, cell cycle and FtsZ localization were recovered when the ftsA cells were complemented byexpression of gfp-ftsA. By confocal microscopy, we detected the reported localization of GFP-FtsA at the midcell in the wild-typestrain, but we also observed an unexpected localization during cell cycle progression. This pattern was confirmed by expression ofFtsA fused to HA (human influenza hemagglutinin tag) and revealed with an anti-HA monoclonal antibody. These results revealednew features of FtsA and confirmed that it is an essential piece of the cell division mechanism of S. pneumoniae.