Figure 1.

Alignment of PBP2 sequences from N. gonorrhoeae (aligned and clustered with CLUSTALW). The Roman numeral nomenclature and the Uniprot accession number are given on the left. Only positions where at least one sequence differs from the reference sequence from the susceptible strain LM306 [31] (Uniprot accession number #P08149) are shown. Substitutions or insertion shown experimentally to contribute to resistance are highlighted in color: blue [32,33]; pink [34,35]; violet [22]; yellow [34,36,37,38]; and green [39]. Yellow substitutions are specific to resistance to third generation cephalosporins. Green substitutions are responsible for high-level resistance, including to third-generation cephalosporins. This representation allows to clearly distinguish two types of sequences from resistant strains, either with the D346a insertion and few substitution clustered in the C-terminal part, or without the D346a insertion with over 50 substitutions spanning the whole protein.