METALLOSPHAERA PRUNAE, SP-NOV, A NOVEL METAL-MOBILIZING, THERMOACIDOPHILIC ARCHAEUM, ISOLATED FROM A URANIUM-MINE IN GERMANY

A novel coccoid thermoacidophilic metal-mobilizing archaeum has been i solated from a smoldering slag heap of a uranium mine in Thuringen, Ge rmany. The new strain grows between 55 degrees C and 80 degrees C by o xidation of S degrees, pyrite, sphalerite, chalcopyrite or molecular h ydrogen. Alternatively yeast extract, peptone, and beef extract are us ed as energy sources during organotrophic growth. The GC-content of it s DNA is 46 mol%. The cell wall is composed of S-layer protein complex es with P3 symmetry, and, depending on the growth conditions, of an ad ditional fibrillar surface coat. On the basis of the 16S rRNA sequence the new isolate is a member of the genus Metallosphaera, No significa nt DNA homology is detectable with the type strain of Metallosphaera s edula. Therefore, we describe the new isolate as the second species of this genus, which we name Metallosphaera prunae (type strain: Ron 12/ II; DSM 10039).