Shorthorn sculpin

Bohn, A. and B.W. Fallis. 1978. Metal concentrations (As, Cd, Cu, Pb and Zn) in shorthorn sculpins, Myoxocephalus scorpius (Linnaeus), and Arctic char, Salvelinus alpinus (Linnaeus), from the vicinity of Strathcona Sound, Northwest Territories. Water Res. 12 659-663. 

Proteins with specific antifreeze properties were first characterized in winter flounder (Pseiidopleiironectes americanus) and shorthorn sculpin (Yang et al., 1988). The simplest of these proteins, Type I from the winter flounder, are alanine-rich, amphiphilic, a-helices about 3-5 kD in size (Davies and Hew, 1990). 

C/N] rSS3, type I shorthorn sculpin antifreeze protein 33 23 ... 

Figure 4. (a. Top) Schematic top view of shorthorn sculpin antifreeze protein minimized along [122] direction on (2-10). showing binding surface residues and the backbone helix. 

Figure 5. Structural fit of winter flounder antifreeze protein to (201). background structure, and shorthorn sculpin antifreeze protein to (2-10), foreground structure. Both proteins are van der Waals representations of their protein backbones and () carbons. The (201) and (2-10) surfaces arc matched along the symmetry equivalent oxygen positions on both surfaces. Viewed down the c axes of the surfaces.

Figure 12. Snapshot from an 85 ps molecular dynamics simulation of Shorthorn sculpin in a periodic box of waters.

Figure 13. Time averaged RMS fluctuations of C atoms for each of the shorthorn sculpin residues.

Table 2 summarizes parameters in the four simulations performed on the a-helical shorthorn sculpin Type I antifreeze protein. 

Table 2. Summary of the four different simulations performed on the shorthorn sculpin. PBC Periodic Boundary Conditions, LDPB Langevin dynamics Poisson - Boltzmann.

Figure 16. Summary of the results for three different simulations on the Type 1 antifreeze protein, shorthorn sculpin. The PB results are for the simulation that was run at 273 K, Tlie upper left figure compares the average number of hydrogen bonds for each residue ovei the simulations time. The upper right figure and lower left figure compares the ( )/ v dihedral angle RMS fluctuations, respectively. The bottom right figure show s the potential energy as a function of time for the three simulations.

Figure 17. Stereoview of the average structures of the shorthorn sculpin helix from a 120 ps explicit water simulation (darker helix) and a 120 ps implicit water simulation (lighter helix).

Sikes, Analysis of shorthorn sculpin antifreeze protein stereospecific binding to (2 -1 0) faces of ice, Biophys. J., 71 (1996) 8. 

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