title: IMPROVED METHODS FOR THE PREPARATION OF THE SPECIFIC POLYSACCHARIDES OF PNEUMOCOCCUS.
abstract: The specific polysaccharides of Types I and V pneumococcus give sharp equivalence zones and show maximal precipitation with homologous rabbit antisera only when carefully prepared from cultures which have not been neutralized with alkali. The precipitating power of S V toward homologous rabbit antiserum falls off in 0.1 N NaOH even more rapidly than that of S I, dropping to 7 per cent of the original value in 6 days at room temperature. The alkaline solution develops a large absorption peak at 270 mmicro. Directions are given for the preparation of S VII and S XII.
authors.affiliation: Department of Medicine, College of Physicians and Surgeons, Columbia University, the Presbyterian Hospital, and the Department of Microbiology, New York University College of Medicine, New York.
authors.forename: M
authors.initials: M
authors.lastname: Heidelberger
authors.forename: C M
authors.initials: CM
authors.lastname: Macleod
authors.forename: H
authors.initials: H
authors.lastname: Markowitz
authors.forename: A S
authors.initials: AS
authors.lastname: Roe