Re ECF Project: 2007-02

Project Title: Easy identification of dinoflagellates: Phase I - Rapid identification of dinoflagellates with protein/peptide mass fingerprints obtained using MALDI-TOF mass spectrometry

Applicant: Professor Samuel CL Lo of the Hong Kong Polytechnic University

Total Approved Grant: $384,000

Duration: 02/07/2008 to 31/12/2009

Project Status/Remarks: Completed

Scope:
The objective is to develop a fast identification method using peptide fingerprints obtained with matrix-assisted-laser-desorption-ionisation mass spectrometry. It will assist to develop an early warning system of the occurrence of harmful algal blooms.

Summary of the Findings/Outcomes:
Verification of the identities of 21 strains of dinoflagellates (which included some of the more important strains) was successfully completed using PCR-based methodology. After growing these dinoflagellates individually to significant numbers (i.e. more than 100,000 cells), protein were extracted from lysates of these dinoflagellates. Protein extracts were cleaned up by adsorption/elution through either C18 or C4 ziptips. Analysed with a MALDI-TOF mass spectrometer, proteins/peptides expression profiles (PEPs) of all 21 dinoflagellates were obtained. Most of these PEPs are unique and suitable for identification purposes. Further, some individual proteins/peptides that are present specifically in a strain were found. These individual peaks can serve as biomarkers for identification purposes. Information for the establishment of a database containing information on the PEPs and biomarkers were obtained. The whole experimental procedure, counting from sample collection to elucidation of PEPs, can be finished within 4 hours. Therefore, a fast identification tool for dinoflagellates is successfully developed. Lastly, the methodology has successfully been tested in a local Karenia digitata algal bloom. It was found that the PEPs and biomarkers can really be used for identification purposes in real life samples.