A moderately halotolerant, Gram-positive, aerobic, motile, spore-forming bacterium, designated as strain YAS1, was isolated from an olive-brine fermentation rich in aromatic compounds, after enrichment on tyrosol. Strain YAS1 grew between 25 and 45 degrees C and optimally at 37 degrees C. It grew in the presence of 0-15% (v/w) NaCl, with an optimum of 3-6% (v/w) NaCl. The DNA G+C content was found to be 49.9 mol%. Phylogenetic analysis of the 16S rRNA gene revealed that this isolate was a member of the genus Bacillus. The newly isolated strain YAS1 represents the first moderately halotolerant bacterium transforming tyrosol to p-hydroxyphenylacetic acid (PHPA) in the presence of yeast extract.