Measurement of bacteriolytic enzymes.

R. S. Wolfe, J. Bacteriol. 90:395, 1965; J. W. 0.600 Zyskind, P. A. Pattee, and M. Lache, Science E 0.600 10 20 30 40 147:1458, 1965) have been based on the reducpJg PROTEIN tion in turbidity of suspensions of susceptible 0Og PROTEIN bacterial cells. The assay for the Chalaropsis N2 0 acetylhexosaminidase (Hash, Arch. Biochem. < \ Biophys. 102:379, 1963), which was based on the L 0.400 20 reduction in turbidity of suspensions of StaphyloZ coccus aureus cells, was complicated by buffer I 030 effects, and it was difficult to obtain different °C preparations of cells with the same susceptibility m0.05 M, PH 4.8 to lysis. It was observed that isolated cell walls l from different preparations of ctlls were uni15 30 45 60 formly susceptible to lysis. An assay was deSECONDS veloped that was based on reduction in turbidity FIG. 1. Relationship between Chalaropsis B protein of isolated cell walls rather than intact cells. concentration and changes in absorbance of StaphyloThis assay was independent of buffer concentracoccus aureus cell wall suspensions. tion over the range 0.01 to 0.2 M, and different preparations of cell walls showed the' same 0.300 sensitivity. Other bacteriolytic enzymes have z been tested, and the method appears to be apE2 _/ plicable to all enzymes that solubilize the cell z wall murein. In the present study, these enzymes a include: lysozyme, Chalaropsis B enzyme, lysoM 0.-00 staphin (courtesy of Mead Johnson Research °) Center and M. Glenn Koenig), Pseudomonas < enzyme (courtesy of P. A. Pattee), and Myxo0.600 2 4 6 8 10 12 bacter AL-1 enzyme (courtesy of R. S. Wolfe). ug PROTEIN Lysozyme is a p3-1,4-N-acetylmuramidase and E pg PROTEIN Chalaropsis B is a ,B-1 ,4-N, O-diacetylmuramiO 0.500 0