Practice question

Thiomargarita namibiensis discovered on Namibian continental shelf is recognized as largest known bacterium, individual spherical cells reaching 0.3 to 0.75 mm diameter visible to naked eye as pearly sulfur pearls. This Gammaproteobacterium stores intracellular sulfur granules and nitrate within a massive central vacuole occupying 98 percent of cell volume, performing lithotrophic sulfide oxidation as electron donor. Polyploidy with thousands of genome copies distributed peripherally sustains metabolism despite diffusion limits. Size challenges canonical notion of bacteria as strictly microscopic, unlike Escherichia coli or Mycoplasma.