Reference Work Entry

The Prokaryotes

pp 951-964

The Family Heliobacteriaceae

  • Michael T. Madigan


The family Heliobacteriaceae consists of phototrophic bacteria that contain bacteriochlorophyll (Bchl) g (Fig. 1). This unique Bchl, found only in the heliobacteria, distinguishes them from all other anoxygenic phototrophic bacteria (Madigan, 2001; Madigan and Ormerod, 1995b). The heliobacteria were discovered in a very serendipitous fashion by Howard Gest and Jeff Favinger in the early 1980s; a fascinating account of this discovery can be found in Gest (1994). The unique characteristics of heliobacteria were first revealed a few years later with publication of the description of Heliobacterium chlorum (Gest and Favinger, 1983) and the structure of Bchl g (Brockmann and Lipinski, 1983). Subsequent research in the Gest laboratory led to the discovery of Heliobacillus, and with this, the establishment of the family Heliobacteriaceae (Beer-Romero and Gest, 1987). Four genera of heliobacteria are currently recognized: Heliobacterium, Heliobacillus, Heliophilum and Heliorestis (

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