Bacteriophage Tail Components: I. Pteroyl Polyglutamates in T-Even Bacteriophages

A pteroylpolyglutamate has been found to be a constituent of all Escherichia coli T-even bacteriophages and has been characterized with regard to its oxidation state, molecular weight, origin, and location on the phage particle. The phage compound has been shown to be a dihydropteroyl penta- or hexaglutamate on the basis of its chemical and physical properties. Analyses of extracts of uninfected and T2L-infected E. coli have indicated that the phage dihydropteroyl polyglutamate was present only in infected cells. Its synthesis was sensitive to the addition of chloramphenicol before infection, and the compound appeared to be specifically induced by phage infection. Analyses of isolated phage ghosts and tail substructures have shown that each phage particle contains between two and six phage-specific pteroyl derivatives and that the juncture of the phage tail plate with the tail tube is the most likely site of binding of the phage-induced pteroyl compound.