The lipopolysaccharide (LPS) of the Salmonella cell surface serves as the receptor for a very large number of bacterial viruses, The tailspike protein from these viruses recognizes the LPS as its initial receptor. It is proposed that the study of the P22 and epsilon(34) tailspike proteins could serve as a model for the study of the interaction of proteins with LPS. Toward this end, the tailspike protein of the epsilon(34) phage has been identified. The data suggest similarities between the epsilon(34) tailspike protein and the P22 tailspike protein. Some properties related to the interaction of the phage tailspike with its receptor are reported. (C) 1995 Academic Press, Inc.