The text discusses two methods for extracting bacterial components using phenol/water emulsions. The first method, performed at low temperatures, results in the release of glycoproteins (primarily O-antigens) into the aqueous phase, while the phenolic phase contains denatured proteins. The second method, using heated homogeneous phenol/water mixtures, yields protein-free polysaccharides and nucleic acids in the aqueous phase. Both methods allow for the separation of bacterial components, with the first method being particularly effective for isolating glycoproteins and the second for polysaccharides. The text also describes the purification of these components and their antigenic properties. Additionally, it references studies on the binding of phages to bacterial mutants, highlighting the role of surface charge patterns and the distinction between reversible and irreversible binding. The methods described are crucial for understanding bacterial structure and function, as well as for vaccine development. The text emphasizes the importance of temperature and pH in the extraction process and the potential applications of the extracted components in immunology and microbiology.The text discusses two methods for extracting bacterial components using phenol/water emulsions. The first method, performed at low temperatures, results in the release of glycoproteins (primarily O-antigens) into the aqueous phase, while the phenolic phase contains denatured proteins. The second method, using heated homogeneous phenol/water mixtures, yields protein-free polysaccharides and nucleic acids in the aqueous phase. Both methods allow for the separation of bacterial components, with the first method being particularly effective for isolating glycoproteins and the second for polysaccharides. The text also describes the purification of these components and their antigenic properties. Additionally, it references studies on the binding of phages to bacterial mutants, highlighting the role of surface charge patterns and the distinction between reversible and irreversible binding. The methods described are crucial for understanding bacterial structure and function, as well as for vaccine development. The text emphasizes the importance of temperature and pH in the extraction process and the potential applications of the extracted components in immunology and microbiology.