Color enhanced transmission electron micrograph of freeze-etch preparation of Nocardia asteroides cells shows ribbonlike structures which appear to be tightly wrapped cells. N. asteroides are a species of gram-positive, aerobic bacteria, pathogenic in humans. Nocardiosis may occur as a pulmonary infection that spreads, resulting in abscesses in the skin, brain, or other areas. May also give rise to tumors that occur most frequently in the lower extremities, esp. the foot, in which case it is called maduromycosis or Madura food. Magnification x4,300 at 70mm