ABSTRACT
To have a better understanding on the evolution of Metallosphaera sedula-mediated precipitation and the properties of the precipitate synthesized by this species，a newly identified extremely thermophilic strain (YN23) of Metallosphaera sedula was cultured in the medium containing Fe2+ as energy resouTce under optimal condidons (pH1.5，65℃,0.2g·1-1 yeast extract,30g·1-1 Fe2SO4·7H2O and 170rpm)．XRD，EDS，ETIR and SEM reveal the precipitate obtained from YN23-inoculated flasks to be a mixture of potassium jarosite and ammoniojarosite，with morphological features similar to the latter．Precipitation Was first detected once over 90％ of Fe2+ was oxidized at hour 25 with a peak pH value of 1.92，and was ended when precipitate reached the highest point of 7.9g·1-1 at hour 95 with the lowest pH value of 1.32 in solution．Microbial density underwent a rapid increase along with Fe2+ oxidation and a gradual decrease with precipitate piling up.
ABSTRACT
To have a better understanding on the evolution of Metallosphaera sedula-mediated precipitation and the properties of the precipitate synthesized by this species，a newly identified extremely thermophilic strain (YN23) of Metallosphaera sedula was cultured in the medium containing Fe2+ as energy resouTce under optimal condidons (pH1.5，65℃,0.2g·1-1 yeast extract,30g·1-1 Fe2SO4·7H2O and 170rpm)．XRD，EDS，ETIR and SEM reveal the precipitate obtained from YN23-inoculated flasks to be a mixture of potassium jarosite and ammoniojarosite，with morphological features similar to the latter．Precipitation Was first detected once over 90％ of Fe2+ was oxidized at hour 25 with a peak pH value of 1.92，and was ended when precipitate reached the highest point of 7.9g·1-1 at hour 95 with the lowest pH value of 1.32 in solution．Microbial density underwent a rapid increase along with Fe2+ oxidation and a gradual decrease with precipitate piling up.