Pinna nobilis

E. Abderhalden. Die Monoaminosduren des Byssus von Pinna nobilis L, Zeit. physiol. Chem., 1908, 55, 236-240. 

The helical reference conformation in synthetic polypeptides fortunately has a counterpart in a group of fibrous muscle proteins, for one of which. Pinna nobilis tropomyosin, hydrodynamic and light-scattering evidence indicate a helical form. This protein is classified as a globulin by virtue of its insolubility in pure water and yet Kay (1958) has shown that its structure is most consistently interpreted as a rigid rod 1400 A in length with... 

Pinna nobilis tropomyosin contains no proline (Bailey, 1957), which is consistent with a helical molecule. As might be expected from the study of a 5% copolymer of L-tyrosine with L-glutamic acid (see Section III, F), the presence of small amounts of tyrosine and histidine in this protein has no appreciable rotatory effect. This protein contains relatively large amounts of amino acids that do form standard helical polypeptides—glutamic acid, 21 % lysine, 8% alanine, 12% and leucine, 12.5 %—but it also has 4 % valine, 6 % serine, and 13 % aspartic acid. If these residues behaved as they and their analogues appear to do in synthetic polypeptides, either pre-... 

A value of be = —630 is well established for synthetic polypeptides and fibrous proteins. The considerations leading to the reasonable approximation that be of the disordered chain is zero, together with the implied equality of Xo and for this state, have been discussed in Section III, C, 1, and incorporated into the pattern of analysis for partial helical content as set out in Section III, G, 2. A value of ao = 4-650 has been obtained for poly-L-glutamic acid, poly-L-lysine, and Pinna nobilis tropomyosin under the appropriate conditions. As has been stressed, these constants have conformational significance only when a value of 212 nm is used for Xo. 

Marin, F. Luquet, G. 2005. Molluscan biomineralization the proteinaceous constituents of Pinna nobilis L. Material Science and Engineering, C25, 105-111. 

Caspartin, a novel member of the shell cal-dtic prisms of the Mediterranean fan mussel Pinna nobilis. Caspartin (Mr 17 kDa) is acidic due to the high Asp content, and soluble in acetic acid. It selfaggregates spontaneously into multimers. It has been suggested that caspartin may play a central role in calcite prism formation [F. Matin et al., J. Biol. Chem. 2005, 280, 33895],... 

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