The isolation, identification and characteristics of a sulfur-oxidizing bacterium, Acidithiobacillus thiooxidans
一株嗜酸硫氧化细菌的分离鉴定及生长特性

Acidithiobacillus thiooxidans QH-1 was isolated and purified from sludge which was collected from the Qinghe River in Beijing. A preliminary study of the strain's tolerance to several heavy metal ions was made. QH-1 was a Gram-negative, short rod, facultative aerobe. The strain could oxidize reduced sulfur compounds to obtain energy. The strain had a high acid production capacity, was resistant to acid, and showed a long logarithmic growth phase of probably 15 days. The strain grew well in a pH environment between 6.0 and 0.6 and could survive in a low pH environment. Using the 16S rRNA sequence and homology analysis, a phylogenetic tree of the strain with related species was constructed. The results showed that QH-1 is a strain of Acidithiobacillus thiooxidans. QH-1 has a high tolerance to Zn2+ and Cu2+ and a poor tolerance to Mo2+.