Extracting cloned A215L
Earlier experiments showed that sonication was unnecessary to extract lysin activity.
E. coli pellets were suspended in pH 4.5 KAc (25mM) buffer with or without 1M LiCl, pH 5 KAc (30mM) buffer with 1M LiCl or in pH 7 KMOPS (25mM) buffer, incubated for 15 min at 37C. Cells were pelleted (2 min at 14K) and 10ul aliquots of supernatants were assayed (15 min at 37C)
Salt facilitates lysin extraction. Lysin is stable and soluble at acid pH.
