title: Synthesis and release of polyribophosphate by Haemophilus influenzae type b in vitro.
abstract: Polyribophosphate, the capsular polysaccharide antigen of Haemophilus influenzae type b, can be assayed in crude bacterial extracts by a combination of immunoprecipitation, hot-acid extraction, and colorimetry. In vitro, the antigen is synthesized during growth and, in well-buffered media, in early stationary phase as well. It is shed from the cell throughout the course of synthesis, and at 37 C almost all the extractable antigen has been released spontaneously within several hours after synthesis. Various strains are similar in extent of synthesis and gross composition of the antigen; however, strains differ in the rate of release during exponential phase. The antigen is released as (or as part of) a very large structure, although under certain culture conditions much smaller antigenic units are found.
mesh_terms: D000942:Antigens, Bacterial / Q000032:analysis; D003470:Culture Media; D006193:Haemophilus influenzae / Q000254:growth & development / Q000378:metabolism*; D066298:In Vitro Techniques; D008970:Molecular Weight; D010428:Pentosephosphates / Q000096:biosynthesis*; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis* / Q000378:metabolism
chemical_list: D000942:Antigens, Bacterial; D003470:Culture Media; D010428:Pentosephosphates; D011135:Polysaccharides, Bacterial; C003191:polyribose phosphate