Recombinant Vibrio cholerae serotype O1 GTPase Obg/CgtA (cgtA)

Depletion experiments lead to gene down regulation and a dramatic increase in ppGpp levels, like those seen in the stringent response. There is no change in cell morphology in depletion experiments, but cells are very sensitive to the DNA-damaging agent hydroxyurea and are very elongated. Overexpression reduces growth and leads to elongated cells. Overexpression of proteins with C-terminal deletions of 29 or 62 amino acids showed fewer elongated cells.; An essential GTPase which binds GTP, GDP and possibly (p)ppGpp with moderate affinity, with high nucleotide exchange rates and a fairly low GTP hydrolysis rate. It may play a role in control of the cell cycle, stress response, ribosome biogenesis and in those bacteria that undergo differentiation, in morphogenesis control. GTPase activity is stimulated by 50S ribosomal subunits.