FIG 1.

Phylogenetic analysis of selected calcite-precipitating isolates and their closest relatives. Yellow boxes, nonureolytic isolates; orange boxes, isolates with inducible ureolytic activity; pink boxes, isolates that utilize urea as a primary nitrogen source; unfilled boxes, unknown ureolytic ability. The ureolytic potential of closest relatives is not shown. GenBank accession numbers are indicated in parentheses. The percentages of trees in which associated taxa clustered together are shown next to the branches (1,000 bootstraps).