Acetyl xylan esterases and variants thereof having perhydrolytic activity are provided for producing peroxycarboxylic acids from carboxylic acid esters and a source of peroxygen. Multi-component peracid generation systems comprising an enzyme catalyst having perhydrolytic activity are also provided, as are methods of using the present enzyme catalyst to produce peroxycarboxylic acids. The polypeptide having perhydrolytic activity may be used to produce peroxycarboxylic acids suitable for use in a variety of applications such as cleaning, disinfecting, sanitizing, bleaching, wood pulp processing, paper pulp processing, and personal care applications.