New DNA fragment encoding mutant O6-antigen polymerase, useful for identifying Escherichia coli DSM 6601 and for attenuating other O6 serotype strains

摘要

A DNA fragment (I) having a 1444 nucleotide sequence (1) given in the specification, is new. Independent claims are also included for: (1) identifying Escherichia coli DSM 6601 by conventional detection of (I); and (2) attenuating E. coli strains of the O6 serotype by replacing the native wzy gene with (I), using standard methods.