Class D beta-lactamase OXA-57 was identified in a range of isolates of Burkholderia pseudomallei and Burkholderia thailandensis. Comparative kinetic analyses of wild-type and mutant forms of B. pseudomallei OXA-57 are reported. Implications of these data for beta-lactam resistance and the proposed role of Ser-104 in beta-lactam hydrolysis are discussed.
