Structure And Function Of Special Proteins From Mytilus Cornscus

Marine mussels attach securely to solid surfaces in the presence of moisture through aholdfast known as the byssus formed by variant kinds of foot proteins secreted from its footglander, which makes Mytilus foot proteins (mfp) increasingly popular in marine adhesiveprotein researches. Possessing important economic value, Hard-shell mussel Mytiluscoruscus, with strong byssul and excellent adhesion, widely spreads all through the littoralextent of Zhejiang, China, while its foot proteins had rarely been studied. In this study, aproteomic approach was developed for screening new byssal proteins from Mytiluscoruscus. The byssus was divided into two parts and byssal proteins were extracted byacid-urea/acid-guanidine-chloride for shotgun-LC-MS/MS analyzing. MS/MS spectra weresearched against the expressed sequence tag (EST) sequences available in public databasefor Mytilus. Using this approach, we were able to identify partial or full-length sequence oftranscripts that encode14novel byssal proteins. Our observations make obvious the valueof EST libraries when used in conjunction with proteomic approach for the investigation ofbyssal proteins. Based on the sequences and domain analysis, we are able to makehypotheses about the potential contribution of these novel byssal proteins to theconstruction and adhesion of byssus.The researches on antibacterial peptides from Mytilus coruscus, an important mytiluson aquiculture, have significant value that helping people to understand the mechanism ofinnate immune system of this mussel. Using multi-dimensional reverse phase highperformance liquid chromatography (RP-HPLC), a novel antimicrobial peptide namedmytichitin-1was isolated from Mytilus coruscus serum. This peptide consists55aminoacids and has a6621.55Da with6Cysteines presented in its sequence forming3disulfidebonds. Using RACE technique, the full-length (1558bp) of cDNA of mytichitin-1wascloned. A chitin-biding domain was detected by domain analysis and the peptide wasnamed mytichitin-1therefore. The mRNA transcripts of mytichitin-1are mainly detected ingonad, which indicates that mytichitin-1are specifically synthesized and stored in genitalsystem. These results indicated that mytichitin-1was involved in the host immune responseagainst bacterial infection and might contribute to the clearance of invading bacteria.