Related Experiment Video
Updated: May 16, 2025
Identification of Rare Bacterial Pathogens by 16S rRNA Gene Sequencing and MALDI-TOF MS
Published on: July 11, 2016
Comparative analysis of MALDI-TOF MS and RAPD for grouping Streptococcus agalactiae isolated from subclinical
Ligia Beatriz Rizzanti Pereira1, Breno Luis Nery Garcia1, Carlos Eduardo Fidelis1
1Department of Animal Nutrition and Production, School of Veterinary Medicine and Animal Sciences, University of São Paulo, Pirassununga, 13653-900, SP, Brazil.
Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) effectively grouped Streptococcus agalactiae isolates from mastitis. This method correlated well with antimicrobial susceptibility, offering a rapid diagnostic tool for dairy herds.
Area of Science:
- Veterinary Microbiology
- Bacteriology
- Diagnostic Technology
Background:
- Streptococcus agalactiae is a contagious pathogen causing subclinical mastitis in dairy animals.
- Accurate identification and characterization are crucial for managing S. agalactiae outbreaks.
- Antimicrobial susceptibility profiling aids in treatment decisions for mastitis.
Purpose of the Study:
- To evaluate Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) for grouping S. agalactiae isolates.
- To associate antimicrobial susceptibility profiles with MALDI-TOF MS groupings.
- To compare MALDI-TOF MS grouping with Random Amplified Polymorphic DNA (RAPD) clustering.
Main Methods:
- Collected 198 milk samples from cows and buffaloes across three farms.
- Performed antimicrobial susceptibility testing for 10 antimicrobials using Minimum Inhibitory Concentration (MIC).
- Grouped S. agalactiae isolates using MALDI-TOF MS and RAPD analysis.
Main Results:
- MALDI-TOF MS identified 8 distinct groups, successfully grouping all isolates.
- RAPD identified 33 clusters, grouping only 100 isolates.
- Both methods showed isolates from the same herd had similar susceptibility profiles.
- High sensitivity (>90%) observed for ceftiofur, penicillin, oxacillin, amoxicillin, cefquinome, gentamicin, and cefoxitin.
Conclusions:
- MALDI-TOF MS is a valuable tool for rapid grouping of S. agalactiae.
- MALDI-TOF MS grouping aligns with antimicrobial susceptibility patterns.
- MALDI-TOF MS offers a reliable alternative to RAPD for pathogen grouping in mastitis studies.
More Related Videos
Related Concept Videos
01:33Peptide Identification Using Tandem Mass Spectrometry
This technique helps gather information regarding the protein from which the peptide was obtained and to study the peptides’ amino acid sequence. Identifying peptides from a complex mixture is an important component of the growing field of...
01:08Matrix-Assisted Laser Desorption Ionization (MALDI)
The analyte of interest, a biomolecule or a mixture of biomolecules, is mixed with a suitable matrix material. The...