The cell wall receptor for bacteriophage Mu G(−) in Erwinia and Escherichia coli C

Adsorption of bacteriophage Mu with its invertible DNA segment in the G(−) orientation requires a terminal glucose residue for binding to the core lipopolysaccharide (LPS) of Gram‐negative bacteria. Analysis of a Mu‐resistant mutant shows that the receptor for Mu G(−) in Erwinia B374 is a Glc‐β1,6‐Glc disaccharide. A spontaneously occurring host‐range mutant, Mu G(−)h101, grows on Escherichia coli C. The loss of the terminal β1,3‐linked glucose from the LPS of E. coli C leads to resistance to the phage Mu. These mutants are also resistant to phage P1 and D108 which have largely homologous G segments. This shows that Mu G(+) and G(−) phage particles differ with respect to their cell‐wall receptors in the type of glycosidic linkage of a terminal glucose residue: α1, 2 for G(+) and β1,6 for G(−).