The amplification product obtained from the B. Sporpthermodurans CBMAI 148 and CBMAI 155 was purified with PEG 8000 (USB, Cleveland, OH-USA) or with MicroSpin S-400 HR Columns ( Amershan Biosciences, Piscataway, N.J.), and then submitted to nucleotide sequencing in an ABI 3130 XL Genetic Analyzer(Applied Biosystems, Lincoln Centre Drive Foster City, USA) automated DNA sequencer.