PMC

Examples of GV18 locus amplicons from 18 Geobacillus isolates separated in a 2% agarose gel. Lane 1, DNA ladder; lanes 2 to 19, Geobacillus isolates; lane 20, negative control.

HRMA difference curves for the four separate VNTR loci GV4 (A), GV10 (B), GV12 (C), and GV18 (D). Different colors in each series of curves represent different MHTs. The same five isolates were used as a reference control for every locus.

(A and B) Examples of RAPD-PCR banding profiles of 15 isolates from two separate DNA extractions. Lanes 1 and 17, DNA ladder; lanes 2 to 15, isolates; lane 16, negative control. Two major banding patterns can be seen, with the first pattern in lanes 2 to 6 and the second pattern in lanes 7 to 15.

(A) HRMA difference curve for the locus GV12, displaying the difference between MHTs 1 (solid gray line), 3 (solid black line), and 13 (dashed line). Each line of the same shading represents a replicate. (B) The nucleotide sequence alignment of these three genotypes. Note that MHT 3 lacks one repeat unit (42 nucleotides) compared to MHTs 1 and 13.

Minimum spanning tree of 16 MLV-HRMA genotypes obtained from 46 isolates of Geobacillus spp. Each node in a tree represents a different MHT, and the genotype number is indicated by the number in the node itself. Clonal groups are encased in a thin black line. Single-locus-variant genotypes are linked by a solid black line, while double- and triple-locus-variant genotypes are linked by solid gray and dashed lines, respectively. Node size represents the number of isolates associated with each genotype. Black shading indicates powders with high spore counts (>10⁴ CFU ml⁻¹), dark gray shading indicates powders with medium spore counts (10² to 10⁴ CFU ml⁻¹), and light gray shading indicates powders with low spore counts (<10² CFU ml⁻¹).