FIG. 2.

Expression and fractionation of recombinant SA proteins synthesized from pL2SA and pL2SAX in L. lactis MG1820(pILPOL). Proteins were separated by SDS–15% PAGE and revealed by immunoblotting with rabbit anti-SA antiserum. Molecular mass markers were low-range prestained markers (Bio-Rad, Hercules, Calif.). Fractions represent proteins present in the growth medium, proteins released by lysostaphin treatment, and proteins present in the residue after that treatment. Proteins released by boiling of intact cells in Laemmli cracking buffer are presented in the lanes labeled “cracking released.” Arrowhead indicate discrete protein bands of relevant sizes corresponding to SA and SAX derivatives.