Fig. 1.

Deletion of spyA. (A) Chromosomal location of spyA. The white bar indicates deleted region. Arrows below chromosome show locations of primers used for PCR analysis. (B) SpyA protein. Conserved residues required for ADP-ribosyltransferase activity are shown. The gray bar shows protein; the white area represents the deleted region. Numbers above protein indicate residues retained in the deletion construct. (C) PCR using primers shown in panel A. Size standards are shown on the left; sizes of PCR fragments are shown on the right. (D) Western blots to detect SpeA, streptokinase, and Mac in GAS supernatants. Lanes 1 and 2 are mid-log; lanes 3 and 4 are stationary phase. Lanes 1 and 3 are supernatants from the wild type, and lanes 2 and 4 are from the mutant.