False-colour scanning electron micrograph (SEM) of a colony of ^IKlebsiella pneumoniae^i, a species of Gram-negative, rod-like bacterium that causes pneumonia in humans. Species of ^IKlebsiella ^ipossess polysaccharide capsules by means of which they may be divided into various types – types 1-3 contain the more pathogenic organisms and type 3 includes ^IK. pneumoniae^i. Other species are widely distributed in nature, commonly exist in the human intestine, and are occasionally responsible for urinary tract, wound or other infections. Magnification: x8800 at 6×7 cm size.