The sulfur utilization and speciation transformation of two elemental sulfur species (orthorhombic alpha-S-8 and amorphous mu-S) by thermoacidophilic Archaea strain Acidianus manzaensis YN-25 was comparatively studied. The results of cell growth and sulfur oxidation behavior showed that A. manzaensis cultured on mu-S grew faster (about 24h earlier to reach stationary phase than that on alpha-S-8) and produced more H+ and SO42-. Results of scanning electron microscopy indicated that the surfaces of mu-S and alpha-S-8 were differently bio-corroded by A. manzaensis into loose porosities and pits, respectively. Fourier transform-infrared spectroscopy analysis indicated both mu-S and alpha-S-8 were adsorbed by the cells. X-ray diffraction and Raman spectra analysis indicated that mu-S was mostly converted into alpha-S-8 after A. manzaensis cell growth while alpha-S-8 was not transformed into a different allotrope. The fitted result of sulfur K edge XANES spectra further showed that the mu-S after growth of A. manzaensis were composed of 92.1% alpha-S-8 and 7.9% mu-S, while no change in composition for alpha-S-8 was found. (C) 2013 Elsevier Ltd. All rights reserved.