Partial characterization of Mφ-secreted germinants in Hanks with B. anthracis Sterne (black bars) and gerH-null endospores (grey bars). (A) Hanks was used alone or was supplemented with 1 mM Ala, 100 mM His, or 100 mM Ino. (B) Hanks was conditioned with 2 × 106 Mφ/ml for 60 min and then passed through a sterile filter as described in the text. Ala, His, or Ino was added to conditioned Hanks at the concentrations listed above. Radiolabeled endospores were added to a final concentration of 106 endospores/ml and were incubated at room temperature for 60 min. After 60 min, the percentage of endospore germination was calculated as described in the text. Each experiment was performed in triplicate with at least two separate preparations of labeled endospores, and the results are reported with an error of ±1 standard deviation of the mean.