Abstract
This protocol was developed in a study aimed to determine the cellular localization of the lysin of pneumococcal phage SV1 (Frias et al., 2013). We obtained proteins from the surface of Streptococcus pneumoniae by elution with choline or those secreted to the medium. The analysis by Western blot of these fractions allowed us to demonstrate that the phage lysin localizes to the cell wall, associating with choline residues in the teichoic acids. Hence, protein extracts can be used to determine the localization of uncharacterized proteins and can also be useful for other biochemical analyses such as protein identification. This protocol can be easily adapted to different pneumococcal strains and growth conditions and it is well suited to isolate other proteins of interest.
Materials and Reagents
Equipment
Procedure
I. Extraction of choline-binding proteins by choline wash
II. Preparation of culture medium fractions in the presence of 2% choline
Recipes
References
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