In-depth proteomic analysis of the byssus from marine mussel Mytilus coruscus.

Mussels attach to various submerged surfaces by using the byssus, which contains different proteins and is a promising source of water-resistant bio-adhesives for potential use in biotechnological and medical applications. The protein composition of the byssus has not yet been fully understood although at least eleven byssal proteins were characterized previously. In order to increase genomic resources and identify new byssal proteins from mussel Mytilus coruscus, high-throughput Illumina sequencing was undertaken on the foot, and 79,997,776 paired-ends reads were generated, yielding a library containing 88,825ft unigenes. The M. coruscus byssus was divided into three parts, the proximal thread, the distal thread, and the plaque. Byssal proteins from each part of the byssus were analyzed by shotgun-LTQ analysis. The MS/MS spectra were searched against the foot unigenes dataset and 48 byssal proteins were identified from the M. coruscus byssus. From the whole set, 17, 5, and 11 proteins were exclusive to the proximal thread, the distal thread, and the plaque, respectively. These data can be used as a resource for further studies on the roles of byssal proteins in the deposition of different byssus parts (thread vs. plaque) or in the different mechanical properties (tenacity vs. adhesion).