Phylogenetic Evidence for the Existence of Thermophilic Bact

The hot spring sulfur-turf microbial mats of Japan have long been of interest because of their conspicuous appearance. However, the community structure of the mats has yet to be investigated in detail mainly because of the difficulty in cultivating mat-building thermophilic prokaryotes. Microbial mats in thermal habitats have been studied extensively as a peculiar microbial community of the ecosystem, in relation to the phylogeny and evolution of thermophilic prokaryotes, or as a source of new …

…microscopic observation by DAPI staining showed that the sulfur-turf mat of the Nakanoyu hot spring stream at 53° C consists of several morphotypes. In the same microscopic field, the large sausage-shaped bacteria emitted fluorescence only with the rhodamine of the probe specific for sequences of the NAK and GANI phylotypes. The population diversity of the sulfur-turf mats seems to be affected by environmental factors of hot springs, e.g., water temperature, sulfide concentration, and human alteration.