(beg-ee-a-toe-a) is a colourless sulphur bacterium which occurs as filaments of various widths. Beggiatoa
is found in sediments above the reduced zone. It oxidizes hydrogen sulphide, producing elemental sulphur which is deposited within the bacterial cell as sulphur granules. In this delicate filament, the individual sulphur grains can be seen as pink refractile inclusions. Phase contrast.