title: Typing of Ochrobactrum anthropi clinical isolates using automated repetitive extragenic palindromic-polymerase chain reaction DNA fingerprinting and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry.
abstract: BACKGROUND
  Ochrobactrum anthropi (O. anthropi), is a non-fermenting gram-negative bacillus usually found in the environment. Nevertheless, during the past decade it has been identified as pathogenic to immunocompromised patients. In this study, we assessed the usefulness of the automated repetitive extragenic palindromic-polymerase chain reaction (rep-PCR-based DiversiLab™ system, bioMèrieux, France) and of matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF MS) for typing of twentythree O. anthropi clinical isolates that we found over a four-months period (from April 2011 to August 2011) in bacteriemic patients admitted in the same operative unit of our hospital. Pulsed-field gel electrophoresis (PFGE), commonly accepted as the gold standard technique for typing, was also used. Analysis was carried out using the Pearson correlation coefficient to determine the distance matrice and the unweighted pair group method with arithmetic mean (UPGMA) to generate dendogram.
  
  
  RESULTS
  Rep-PCR analysis identified four different patterns: three that clustered together with 97% or more pattern similarity, and one whose members showed < 95% pattern similarity. Interestingly, strains isolated later (from 11/06/2011 to 24/08/2011) displayed a pattern with 99% similarity. MALDI-TOF MS evaluation clustered the twentythree strains of O. anthropi into a single group containing four distinct subgroups, each comprising the majority of strains clustering below 5 distance levels, indicating a high similarity between the isolates.
  
  
  CONCLUSIONS
  Our results indicate that these isolates are clonally-related and the methods used afforded a valuable contribution to the epidemiology, prevention and control of the infections caused by this pathogen.
authors.forename: Angela
authors.initials: A
authors.lastname: Quirino
authors.forename: Giovanna
authors.initials: G
authors.lastname: Pulcrano
authors.forename: Linda
authors.initials: L
authors.lastname: Rametti
authors.forename: Rossana
authors.initials: R
authors.lastname: Puccio
authors.forename: Nadia
authors.initials: N
authors.lastname: Marascio
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Catania
authors.forename: Giovanni
authors.initials: G
authors.lastname: Matera
authors.affiliation: Institute of Microbiology, Department of Health Sciences, "Magna Graecia" University, Viale Europa, Catanzaro, Italy. mliberto@unicz.it.
authors.forename: Maria Carla
authors.initials: MC
authors.lastname: Liberto
authors.forename: Alfredo
authors.initials: A
authors.lastname: Focà
mesh_terms: D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology; D015373:Bacterial Typing Techniques / Q000379:methods*; D016000:Cluster Analysis; D016172:DNA Fingerprinting / Q000379:methods*; D016521:Electrophoresis, Gel, Pulsed-Field; D005602:France / Q000453:epidemiology; D005838:Genotype; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000382:microbiology*; D006761:Hospitals; D006801:Humans; D017720:Molecular Epidemiology; D020621:Ochrobactrum anthropi / Q000145:classification* / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*