Chemical extraction versus direct smear for MALDI-TOF mass spectrometry identification of anaerobic bacteria
Details
Serval ID
serval:BIB_C4A9049407D1
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Chemical extraction versus direct smear for MALDI-TOF mass spectrometry identification of anaerobic bacteria
Journal
Anaerobe
ISSN
1075-9964
Publication state
Published
Issued date
06/2012
Volume
18
Number
3
Pages
294-7
Language
english
Abstract
In the present study, two pre-analytic processes for mass spectrometric bacterial identification were compared: the time-consuming reference method, chemical extraction, and the direct smear technique directly using cultured colonies without any further preparation. These pre-analytic processes were compared in the identification of a total of 238 strains of anaerobic bacteria representing 34 species. The results showed that 218/238 strains were identified following chemical extraction, 185 identifications (77.7%) were secured to both genus and species [log(score) > 2.0] whereas 33 identifications (14%) were secured to genus only [log(score) between 1.7 and 2.0]. Following direct smear, 207/238 anaerobic bacteria were identified, 158 identifications (66.4%) were secured to both genus and species [log(score) > 2.0] whereas 49 identifications were secured to genus only [log(score) between 1.7 and 2.0]. Twenty strains were not identified [log(score) < 1.7] by MALDI-TOF MS following chemical extraction whereas 31 strains were not identified with the direct smear technique. Although direct smear led to a significant decrease of the log(score) values for the Clostridium genus and the Gram positive anaerobic bacteria (GPAC) group (p < 0.0001, Wilcoxon test), identification to both species and genus were not changed. However these differences were not statistically significant (p = 0.1, Chi square). Therefore, MALDI-TOF MS identification following the direct smear technique appears to both non-inferior to the reference method and relevant for anaerobic bacteria identification.
Keywords
*Metabolome, *Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Bacteria, Anaerobic/*classification/genetics/metabolism, Bacterial Proteins/metabolism, Molecular Typing, RNA, Ribosomal, 16S/genetics, Sequence Analysis, DNA
Create date
18/07/2019 12:48
Last modification date
21/08/2019 5:33