You are here:
MATRIX ASSISTED LASER DESORPTION/IONIZATION TIME OF FLIGHT MASS SPECTROMETRY BASED ANALYSIS OF GIARDIA LAMBLIA
Citation:
VILLEGAS, E., S. GLASSMEYER, M. W. WARE, S. L. HAYES, AND F. W. SCHAEFER. MATRIX ASSISTED LASER DESORPTION/IONIZATION TIME OF FLIGHT MASS SPECTROMETRY BASED ANALYSIS OF GIARDIA LAMBLIA. Presented at IX International Workshop on Opportunistic Protists, Lisbon, PRINCIPLE, June 20 - 24, 2006.
Impact/Purpose:
1) Refine new, practical methods for the detection of CCL-related and emerging waterborne human protozoa.
2) Perform field tests of devices or methods that have been developed under this task.
3) Evaluate these methods or devices in a variety of water matrices and parasite concentrations.
This work in this task supports CCL2 and 3 and is expected to be completed by 9/07.
Description:
Giardia lamblia is a zoonotic protozoan parasite that is a leading cause of drinking water related gastro-intestinal disease outbreaks worldwide. Due to the genotypic complexity and high prevalence of this parasite in the environment, numerous research studies are being done to genotype the different Giardia species present in clinical and environmental samples. One approach used to genotype these pathogens is nested PCR in combination with restriction fragment length polymorphism (RFLP) analysis. However, this approach can be labor intensive, expensive, and prone to PCR contamination. In this study, we evaluated the utility of matrix assisted desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) as an alternative method to identify different Giardia species. MALDI-TOF MS analyses of G. lamblia and G. muris reveal mass spectral fingerprints that contain genus and species specific peaks. Further analysis of flow cytometry sorted G. lamblia trophozoites identified trophozoite specific peaks that constituted a part of the total mass spectral fingerprint detected from live G. lamblia cysts. In addition, to determine the stability of these G. lamblia mass spectral profiles, live cysts and cysts killed by physical and/or chemical disinfection were also analyzed by MALDI-TOF MS. Results reveal the loss of specific peaks in killed cysts as compared to live cysts. These results suggest that a MALDI-TOF MS based proteomics approach is effective at identifying unique mass spectral fingerprints from two different Giardia species and differentiating viable from non-viable cysts. This study presents an alternative approach for identifying various clinical and/or environmental Giardia isolates as well as a method to evaluate various drinking water treatment and disinfection efficacies.