The microbial ecology of a high-temperature near-neutral spring situated in Rotorua, New Zealand

A combination of both culture and culture-independent techniques were used to investigate the microbial ecology of a near-neutral, high-temperature hot spring (designated AQ1) in Rotorua, New Zealand. The active microbial members of the community were targeted by analyzing biofilms that developed on surfaces incubated in situ in AQ1. Colonization of surfaces was rapid as indicated by ATP assay and microscopic observation. DNA-based analysis of both colonized surfaces and pool water from AQ1 revealed an exclusively archaeal community. Different colonization patterns were observed on glass slides incubated near the pool surface or at depth. Slides incubated at the surface were colonized exclusively by Pyrobaculum species, while at greater depth a novel coccus was also observed and detected by DGGE. Sequence analysis revealed the coccus was related to Aeropyrum pernix. Two microorganisms were isolated from AQ1 pool water, namely Ignisphaera aggregans AQ1.S1 T and a species of Pyrobaculum, isolate AQ1.S2.