Direct common gram-negative bacterial identification from positive blood culture bottles by SELDI-TOF MS

A protein database was constructed and validated with identification rate over 90% for the 4 most common Gram-negative bacteria on agar plates. By protein masses comparison, 120 bacteria of the 4 species from blood culture bottles were identified. The concordance was high (Kappa=0.906) between our method and conventional approach. •We constructed a protein database including the 4 most common gram-negative bacteria.•The database was validated by 327 clinical isolates.•The identification rate was over 90% for the 4 bacteria on agar plates.•By protein masses comparison, we identified bacteria from blood culture bottles.•The concordance was high (K=0.906) between our method and conventional approach.