abstract |
Disclosed and claimed are mutants of gram negative bacteria; The bacterium is SEQ ID NO: 2, 6, 9, 12, 16, 19, 22, 25, 28, 31, 34, 37, 40, 43, 46, 49, 52, 55, 58, 61, 64, 67, 70 70%, 75%, 80%, 85%, 90%, 95% of the amino acid sequence encoded by a nucleotide sequence selected from the group consisting of nucleotide sequences identified as: 75, 78, 81, 84, 87, 90 or 93 At least one mutation of a nucleotide sequence encoding a polypeptide having at least 96%, 97%, 98% or 99% homology; The mutation attenuates the pathogenesis of the bacteria. Immunogenic compositions and vaccines containing such mutants are also disclosed and claimed. |