Lysin binding (depletion) assay
Ammonium sulfate precipitated (70%) lysin (sample 2) was dissolved in DW (low salt to minimize activity). Aliquots of concentrated (~108 cells/ml) NC64a cells were added to 25ul aliquots of lysin. Suspensions were incubated 5 min at RT, cells were pelleted and supernatants were analyzed by SDS gel electrophoresis - low (left) concentrations and high (right) concentrations. Cell pellets from the 10ul cell sample were also analyzed by SDS gel electrophoresis
In no case did binding to cells deplete a protein component from the lysin prep. Proteins were released from cells (lysin activity presumably) in proportion to cell concentration. Rubisco large subunit is apparent among Chlorella cell components. The "bound material" is obviously obscured by proteins released from cells.
Binding is at best weak. Future experiments should employ cell ghosts and incubations should be on ice.
