Extraction, purification and characterization of green mussel Perna viridis foot protein-3 (pvfp-3)

• Main Author: Kwan, Kerby Cheuk Hay
• Other Authors: School of Materials Science and Engineering
• Format: Final Year Project
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering::Materials::Biomaterials
• Online Access: http://hdl.handle.net/10356/46452
• Institution: Nanyang Technological University

Green mussel (Perna viridis) are known to secrete precursor adhesive proteins that enable them to stick tenaciously to submerged surfaces. A total of eight proteins have been discovered upon the analysis of the adhesive plaque from other mussel species. The aim of this project is to examine a specific protein from the green mussel, named Pvfp-3, as MALDI-based molecular weight analysis previously indicated a significant amount of this particular protein at the adhesive plaque/surface interface. Post-translational modified tyrosine L-dihydroxyphenylalanine (DOPA) protein is believed to play a major role in the adhesion and rapid cross-linking that enables the plaque to adhere to the substrate viciously. As not much research on the protein composition of Perna viridis species has been done to date, the main objective of this project is to improve the extraction and purification protocol of the Pvfp-3 such that the increased yield will allow further biophysical characterization processes to be conducted. Extraction by means of homogenization and centrifugation provides an initial crude protein separation that is then followed by purification through reverse-phase HPLC to yield superior results compared to the previous protocols. Molecular weight measurement using MALDI-TOF indicated distinct 5.3kDa peaks in the purified sample suggesting successful techniques were utilized. Positive DOPA indicators through Arnow staining and gel electrophoresis suggest the presence of DOPA which corresponds to the suggestion that the recovered sample is indeed Pvfp-3. Results suggest that previous extraction and purification model, based on the Mytilus edulis species, are not completely compatible with the Perna viridis species and modifications are required to optimize the extraction yield of similar proteins.