PURIFICATION OF COLLAGEN-BINDING PROTEINS OF LACTOBACILLUS-REUTERI NCIB-11951

Collagen type-I-binding proteins of Lactobacillus reuteri NCIB 11951 w ere purified. The cell surface proteins were affinity purified on coll agen Sepharose and eluted with an NaCl gradient. Two protein bands wer e eluted from the column (29 kDa and 31 kDa), and both bound radio-lab eled collagen type I. Rabbit antisera raised against the 29 kDa and 3l kDa protein reacted with the affinity-purified proteins in a Western b lot with whole-cell extract used as antigen. The N-terminal sequence o f the 29-kDa and 31-kDa proteins demonstrated the closest homologies w ith internal sequences from an Escherichia coli trigger factor protein (TIG.ECOLI). Out of nine other lactobacilli, the antisera reacted onl y with the L. reuteri and not with the other species tested.