Phage Receptor Material in Lactobacillus casei Cell Wall

A trichloroacetic acid (TCA)‐soluble fraction, extracted using cold TCA, was derived from the cell wall of Lactobacillus casei strain S‐1. It not only inhibited the adsorption of phage J‐l but also desorbed these phages, in their active form, which had previously been adsorbed onto the cell walls. l‐Rhamnose, one of the components of this TCA‐soluble fraction, had an identical activity to this TCA‐soluble fraction, on phage adsorption. This suggested that l‐rhamnose is a part of phage receptor material in the cell wall of L. casei strain S‐l; and the binding of the phage to the cell wall is reversible, even at 37 C.