OBJECTIVETo establish a domestic database of Enterobacteria cloacae (E. cloacae), and improve the identification efficiency using peptide mass fingerprinting.

METHODSPeptide mass fingerprinting was used for the identification and subtyping of E. cloacae. Eighty-seven strains, identified based on hsp60 genotyping, were used to construct and evaluate a new reference database.

RESULTSCompared with the original reference database, the identification efficiency and accuracy of the new reference database was greatly improved at the species level. The first super reference database for E. cloacae identification was also constructed and evaluated. Based on the super reference database and the main spectra projection dendrogram, E. cloacae strains were divided into two clades.

CONCLUSIONPeptide mass fingerprinting is a powerful method to identify and subtype E. cloacae, and the use of this method will allow us to obtain more information to understand the heterogeneous organism E. cloacae.