Evaluation of Surface Structure of Escherichia coli Using Polypyrrole Matrix

We propose a method to evaluate the surface structure of Escherichia coli focusing on the doping state of bacterial cells into polypyrrole (PPy) matrix. We found that the orientation of doping states of E. coli O rough was different from those of other serotypes of E. coli cells, which had O-antigen on their outer membrane. The results indicated that more than seventy percent of E. coli cells having O-antigen was horizontally doped into PPy matrix based on the chemical structure and the placement of O-antigen. On the other hand, the percentage for horizontal doping state of E. coli O rough cells was only approximately fifty percent. Moreover, the cells of each E. coli serotypes were specifically bound to their own shape-complementary cavities on the microspheres, but the binding affinity of E. coli O rough was a bit lower than that of other serotypes.