Vt. Marteinsson et al., FIRST ISOLATION OF THERMOPHILIC AEROBIC NON-SPORULATING HETEROTROPHICBACTERIA FROM DEEP-SEA HYDROTHERMAL VENTS, FEMS microbiology, ecology, 18(3), 1995, pp. 163-174
Thermophilic aerobic non-sporulating heterotrophic bacteria were isola
ted for the first time from deep-sea hydrothermal vents, Samples were
taken at Snakepit (Mid-Atlantic Ridge) and Guaymas Basin (Gulf of Cali
fornia). Isolates consisting of pleomorphic rods, single cells or pair
s, formed filaments of variable length, and grew at 70 degrees C or so
me up to 80 degrees C. They were halotolerant and unable to grow anaer
obically, except some strains in the presence of nitrate. A numerical
classification based on phenotypic features was performed on the isola
tes, including three reference strains Rhodothermus marinus (R-10), Th
ermus aquaticus (YT-1) and Thermus scotoductus (X-1) and one yellow pi
gmented Thermus strain. Results from unweighted average linkage (UPGMA
) clustering applied to a similarity matrix derived from the simple ma
tching (S-SM) coefficient showed the formation of five main clusters w
hich were defined for at least 80% similarity, whereas only three isol
ates remained outside of the clusters. One reference strain (X-1) clus
tered with one isolate at a level of 83% and between 76-78% with other
clusters. The other reference strains showed less than 55% similarity
with the deep-sea isolates.