Fig. 2
From: Identification of the minimal cytolytic unit for streptolysin S and an expansion of the toxin family
Assessment of the hemolytic activity of truncated SLS precursor peptides expressed in S. pyogenes ΔsagA. a Residues of the SagA core peptide are numbered. Potentially modified residues of SLS are blue, while those known to be heterocyclized when SagA is modified with purified SagBCD are purple. The predicted leader cleavage site is indicated with a caret. The positions of stop codons introduced in SagA are marked with asterisks (yields truncation mutants listed in panel B). The minimal core region required for hemolytic activity of SLS in S. pyogenes ΔsagA (SagA24–34) is underlined (see panel B). b The labels correspond to the SagA truncation mutants described in panel A. A representative colony on blood agar of GAS M1 ΔsagA expressing each precursor from pDCerm is shown. The colony labeled “Empty” was a negative control containing pDCerm vector