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Zeolites with pores of different dimensions within the same structure can present specific catalytic properties derived from the possibilities of performing molecular traffic control 1 when reactants and/or products of different molecular dimensions could react and diffuse. Some examples of zeolites with pores of different sizes within the same structure are SSZ-51, 2 MCM-68, 3 ITQ-22, 4 IM-12, 5 ITQ-15, 6 and ITQ-33. 7 Special mention requires the zeolite ITQ-13 (ITH), whose structure was solved from single crystal diffraction data, and presents a system of pores by 9 × 10 × 10 rings, with pore diameters of 4.0 Å × 4.9 Å 2 , 4.8 Å × 5.7 Å 2 , and 4.7 Å × 5.1 Å 2 , respectively. 8 Because of its peculiar pore system it presents excellent catalytic properties for producing propylene when used as a FCC additive 9 as well as for toluene disproportionation. 10 ITQ-13 zeolite was synthesized 11 with hexamethonium [hexane-1,6-bis(trimethylammonium)] as structure directing agent (SDA). We have seen that the ITH structure can have at least one hypothetical polymorph (polymorph B, now on named ITQ-34) that can also be described as a stacking of zeolitic sheets connected forming double four-rings (D4R). However, while in the case of ITQ-13 (polymorph A), these sheets extend in the bc plane and stack along the a direction with a stacking sequence AAA...; in the case of ITQ-34 the stacking sequence is ABAB..., where B corresponds to the A sheet of ITQ-13 after applying a 180°rotation around the b axis and a translation of 1 / 2 along the c axis. Then, the cell axis of both polymorphs will be closely related, the b and c axis being identical because of the common basic sheet. The a axis of ITQ-34 will be double of that in ITQ-13 because of the different stacking sequence (ABAB... vs AAA...). However, to adopt a standard setting for the space group expected for ITQ-34 (Cmcm), the cell axis of ITQ-34 will need to be defined as a (ITQ-34) ) b (ITQ-13) , b (ITQ-34) ) c (ITQ-13) , and c (ITQ-34) ) 2a (ITQ-13) (Figure 1). Also, both structures will have an identical framework density of 17.4 T atoms per 1000 Å 3 .If one simulates the structure of ITQ-34 it can be seen by simple docking that hexamethonium could, in principle, be an adequate SDA for the synthesis of this material. More specifically, when a computational approach (see Supporting Information) has been applied to calculate the short-range Van der Waals (E1) and the electrostatic (E2) interactions between the optimized zeolite-SDA system for ITQ-13 and ITQ-34 and hexamethonium, it is possible to see (Table S1 in Supporting Information) that this SDA orientates slightly better toward ITQ-13 than to ITQ-34. Then, when exploring the experimental synthesis conditions in a wide range of gel compositions using hexamethonium as SDA we found that in no case was the pure ITQ-34 obtained, but mixtures of ITQ-13 and

SUMMARYPurified foot-and-mouth disease virus (FMDV) of type OIK was treated with several endopeptidases of differing specificity. The immunizing protein VPTh r was cleaved into two detectable fragments by all enzymes except for glutamic acid-specific Staphylococcus aureus V8 protease. The longest fragments were generated by mouse submaxillary gland protease and the shortest by trypsin treatment of the intact virion. Several fragments, including the peptides resulting from the cyanogen bromide (CNBr) cleavage of the isolated protein VPTh r, were characterized in terms of their molecular weights, N-and C-terminal amino acids, and ability to induce virus-specific antibodies. The order of the fragments along the protein was determined, and then located on the amino acid sequence of the protein. Two enzyme-sensitive areas of the protein were found on the surface of the virion: between sequence positions 138 and 154 and between portion 200 and the C terminus. Peptides containing these sections were able to induce neutralizing antibodies against the homologous FMDV. When the virus was treated with trypsin or with chymotrypsin, several amino acids between the detectable fragments were lost and the infectivity of the virus was reduced. The infectivity was retained, however, when the enzyme treatment resulted in cleavage of protein with no loss of amino acids or only the cutting away of the C-terminal section. These results suggest that the property of cell attachment is restricted to small regions of the surface of the virus particle.

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