Rates of germination of wild-type and ΔgerD spores prepared in RM. Wild-type (PS832) and ΔgerD (FB62) spores prepared in RM were spotted on agar slides with kanamycin and either l-alanine or AGFK, and spore germination was assessed by examining ∼100 spores under phase-contrast microscopy as described in Materials and Methods. ○, wild-type spores with l-alanine; ▵, wild-type spores with AGFK; •, ΔgerD spores with l-alanine; ▴, ΔgerD spores with AGFK.