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Abstract：
Monomolecular arrays of protein subunits forming surface layers (S-layers) are the most common outermost cell envelope components of prokaryotic organisms (bacteria and archaea). Since S-layers are periodic structures, they exhibit identical physicochemical properties for each constituent molecular unit down to the sub-nanometer level. Pores passing through S-layers show identical size and morphology and are in the range of ultrafiltration membranes. The functional groups on the surface and in the pores of the S-layer protein lattice are accessible for chemical modifications and for binding functional molecules in very precise fashion. S-layer ultrafiltration membranes (SUMs) can be produced by depositing S-layer fragments as a coherent (multi)layer on microfiltration membranes. After inter- and intramolecular crosslinking of the composite structure, the chemical and thermal resistance of these membranes was shown to be comparable to polyamide membranes. Chemical modification and/or specific binding of differently sized molecules allow the tuning of the surface properties and molecular sieving characteristics of SUMs. SUMs can be utilized as matrices for the controlled immobilization of functional biomolecules (e.g., ligands, enzymes, antibodies, and antigens) as required for many applications (e.g., biosensors, diagnostics, enzyme- and affinity-membranes). Finally, SUM represent unique supporting structures for stabilizing functional lipid membranes at meso- and macroscopic scale.
摘要：
形成表面层（S层）的蛋白质亚基的单分子阵列是原核生物（细菌和古细菌）最常见的最外层细胞包膜成分。由于S层是周期性结构，它们对于每个组成分子单元表现出相同的物理化学性质，直到亚纳米级。穿过S层的孔显示出相同的尺寸和形态，并且在超滤膜的范围内。S层蛋白质晶格的表面上和孔中的官能团可用于化学修饰和以非常精确的方式结合功能分子。S层超滤膜(SUM)可以通过将S层片段作为连贯(多)层沉积在微滤膜上来生产。在复合结构的分子间和分子内交联后，这些膜的耐化学性和耐热性与聚酰胺膜相当。不同大小的分子的化学修饰和/或特异性结合允许调整SUM的表面性质和分子筛筛选特性。SUM可以用作用于功能性生物分子的受控固定的基质（例如，配体，酶，抗体，和抗原)，如许多应用所需(例如，生物传感器，诊断,酶膜和亲和膜)。最后,SUM代表用于在中观和宏观尺度上稳定功能性脂质膜的独特支持结构。
