Relation between wall teichoic acid content of Bacillus subtilis and efficiency of adsorption of bacteriophages SP 50 and phi 25.

Efficient adsorption of bacteriophages SP 50 and phi 25 occurred only to bacilli that contained wall teichoic acid and neither phage bound to phosphate limited bacilli that contained teichuronic acid instead of teichoic acid. Though both phages require the presence of teichoic acid, their receptors are not identical. Efficient binding of phage phi 25 required the presence of greater proportions of teichoic acid in the wall and the receptor for this phage was destroyed when bacteria or isolated walls were heated at pH 4 whereas the ability of these samples to bind phage SP 50 was unaffected by such treatment. Efficient binding of phage SP 50 was not highly dependent on the presence of glucosyl substituents on the teichoic acid. Such substituents were required for phage phi 25 binding though their anomeric configuration appeared to be unimportant since the phages bound well to both strains W23 and 168, the wall teichoic acids of which carry glucosyl substituents of opposite anomeric configuration. The differences in the nature of the receptors may be of value in the use of the phages as probes for the location and distribution of teichoic acid in the wall.