The study of the adductor muscle-shell interface structure in three Mollusc species

The adductor muscle scar（AMS） is the fixation point of adductor muscle to the shell. It is an important organicinorganic interface and stress distribution area. Despite recent advances, our understanding of the structure and composition of the AMS remain limited. Here, we report study on the AMS of three bivalves： Mytilus coruscus,Chlamys farreri and Ruditapes philippinarum. Results showed that there were significant differences among their AMS structures. Both M. coruscus and C. farreri were found to have a columnar layer above the nacreous platelet shell structure at the AMS and this layer was more organized in M. coruscus. There was no distinguishable twolayer structure in R. philippinarum. Atomic force microscopy（AFM） and Fourier transform infrared spectroscopy（FT-IR） results showed that the AMS was much smoother than the nacreous inner shell in all the three species and the AMS had minor different compositions from the nacreous shell layer. SDS-PAGE（sodium dodecyl-sulfate polyacrylamide gel electophoresis） study of the proteins isolated from the interface indicated that there was a 70 k Da protein which seemed to be specifically located to the highly organized columnar AMS structure in Mytilus coruscus. Further analysis of this protein showed it contained high level of Asx（Asp＋Asn）, Glx（Glu＋Gln） and Gly.The special structure and composition of the AMS might play important roles in the stability, adhesion and function at this stress distribution site.

Analytical methods for nano-bio interface interactions

Knowledge on the interactions between engineered nanomaterials(ENMs) and biological systems is critical both for the assessment of biological effects of ENMs and for the rational design of ENM-based products. However, probing the events that occur at the nano-bio interface remains extremely challenging due to their complex and dynamic nature. So far, the understanding of mechanisms underlying nano-bio interactions has been mainly limited by the lack of proper analytical techniques with sufficient sensitivity, selectivity and resolution for characterization of nano-bio interface events. Moreover, many classic bioanalytical methods are not suitable for direct measurement of nano-bio interface interactions. These have made establishing analytical methodologies for systematic and comprehensive study of nano-bio interface one of the most focused areas in nanobiology. In this review we have discussed some representative developments regarding analytical techniques for nano-bio interface characterization, including the improvements of traditional methods and the emergence of powerful new technologies. These developments have allowed ultrasensitive, real-time analysis of interactions between ENMs and biomolecules, transformations of ENMs in biological environment, and impacts of ENMs on living systems on molecular or cellular level.