The lytA Gene and the DNA Region Located Downstream of This Gene Are Not Involved in the Formation of the Type 3 Capsular Polysaccharide of Streptococcus pneumoniae

Streptococcus pneumoniae strain M31, an unencapsulated, serotype 2 (S2⁻) mutant having a deletion of at least 5.5 kb containing the gene lytA that encodes the main pneumococcal autolysin, was transformed to the encapsulated serotype 3 (S3⁺) with DNA from the clinical pneumococcal strain 406. Hybridization analysis revealed that the S3⁺ transformants also have the deletion demonstrating that lytA and the DNA region located downstream of this gene are not involved in the encapsulation of S. pneumoniae. Received: 29 February 1996 / Accepted: 1 March 1996