1985 Volume 31 Issue 1 Pages 17-28
The occurrence of vast amounts of streamers was observed widely in acid mine drainage water from the abandoned Matsuo sulfur and iron sulfide mine area. The acid streamers were commonly white or cream colored and gelatinous, and were composed of many fine fibers. The streamers showed strong oxidizing activity of ferrous iron, sulfur and thiosulfate in an inorganic acid environment. Microscopic examinations of the streamers indicated that morphologically-similar bacterial rods multiplied in a long oriented cell chain and that a great number of the bacterial cell chains were combined in a zoogleal big conglomeration. The acid streamers were a mass of acidophilic, obligately chemolithotrophic iron-oxidizing bacteria, proved to be Thiobacillus ferrooxidans, which were embedded in a gelatinous matrix.