FIG. 1.

Dendrogram obtained for several oxacillinases by parsimony analysis (35). Branch lengths are drawn to scale and are proportional to the number of amino acid changes. The number of changes is indicated above each branch, and the percent values at branching points (underlined) refer to the number of times that a particular node was found in 100 bootstrap replications. The distance along the vertical axis has no significance. Numbers in parentheses indicate percentages of amino acid identity with the β-lactamase OXA-69. Bacterial species names are for those oxacillinases that are naturally occurring.