title: Towards Raman-based epidemiological typing of Pseudomonas aeruginosa.
abstract: Raman spectra of bacteria can be used as highly specific fingerprints, enabling discrimination at strain level. Pseudomonas aeruginosa strains can be strongly pigmented, making it difficult to obtain high quality spectra of such isolates due to high fluorescent spectral backgrounds. Furthermore, the spectra that could be measured with acceptable quality often showed large spectral variations limiting the reproducibility required for strain level discrimination. P. aeruginosa produces a characteristic yellowish green fluorescent pigment, called pyoverdin. Applying a washing procedure to reduce the amount of fluorescent pigment, enabled the highly pigmented isolates to be measured with sufficient spectral quality. Isolation of the pigment/pyoverdin spectral features, together with spectral scaling methods improved reproducibility. It will be important to analyze the range of the spectral variations that can occur and ensure the correction of all of these factors to obtain the highest reproducibility required for strain level typing.
authors.affiliation: Department of Medical Microbiology and Infectious Diseases, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Diana F M
authors.initials: DF
authors.lastname: Willemse-Erix
authors.forename: Jan-willem
authors.initials: JW
authors.lastname: Jachtenberg
authors.forename: Tom Bakker
authors.initials: TB
authors.lastname: Schut
authors.forename: Willem
authors.initials: W
authors.lastname: van Leeuwen
authors.forename: Alex
authors.initials: A
authors.lastname: van Belkum
authors.forename: Gerwin
authors.initials: G
authors.lastname: Puppels
authors.forename: Kees
authors.initials: K
authors.lastname: Maquelin
mesh_terms: D000465:Algorithms; D015373:Bacterial Typing Techniques / Q000379:methods*; D004784:Environmental Monitoring / Q000379:methods*; D009842:Oligopeptides / Q000032:analysis*; D011550:Pseudomonas aeruginosa / Q000145:classification* / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D009842:Oligopeptides; C042453:pyoverdin