Balamuthia mandrillaris was isolated from a sample of soil from a plant in the home of a child who died of amebic encephalitis. These free living amoebae can be opportunistic pathogens, and in some cases have been diagnosed as the causative agent of the usually fatal amebic encephalitis. Balamuthia feed by inserting the tips of their pseudopodia into cells. Naegleria and Acanthamoeba, other opportunistic amoeboid pathogens, feed by phagocytosis. The cells were grown in axenic media. Then they were photographed with a Canon Power Shot G3 with a setting at ISO 50 with an optical microlens at 4X and the quality set at RAW. The camera was attached to the phototube of the microscope with a 3X lens and photographed in phase contrast with a 100X oil immersion objective. Live amoebae were placed in a chamber prepared by inverting a coverslip with/or without cultured mammalian cells onto a 3X1 inch microscope slide with a thin rim of Vaseline; melted paraffin was brushed around the edge of the coverslip to seal it to the slide. Such cultures could be maintained for several days at room temperature. Further details are available in the attached publication. Other members of the linked video group are Naegleria and Acanthamoeba.
Biological Process: Pseudopodium organization, Pseudopodium assembly, Pseudopodium retraction
Author: Thelma Dunnebacke
Source: The Cell: An Image Library
