FIG 2.

Effect of expression of BxpB and ExsFB on BclA spore surface distribution. (A) Amino acid sequence alignment of BxpB and ExsFB with sequence identities and similarities (denoted by plus sign) indicated. The arrow denotes the position where the chimeric proteins were fused. (B) Microarray-based RNA expression profiles of the exosporium determinants bxpB, cotY, exsY, and exsFB during the in vitro growth and sporulation cycle. Microarray data were from Bergman et al. (43). (C) Representations of the full-length and chimeric bxpB and exsFB determinants expressed from either the bxpB or exsFB promoters. (D) Bright-field and anti-BclA fluorescence of spores of the Sterne parent strain and the ΔbxpB-, ΔexsFB-, and ΔbxpB ΔexsFB-null mutants bearing the plasmid-borne bxpB or exsFB determinants expressed from their native or swapped promoter sequences where indicated. Spores were reacted with anti-BclA polyclonal serum and goat anti-rabbit-Alexa Fluor 568 secondary antibodies.