Biomacromolecules Subject

Based on these observations, Wang and Caruso [237] have described an effective method for the fabrication of robust zeolitic membranes with three-dimensional interconnected macroporous (1.2 pm in diameter) stmctures from mesoporous silica spheres previously seeded with silicalite-1 nanoparticles subjected to a conventional hydrothermal treatment. Subsequently, the zeolite membrane modification via the layer-by-layer electrostatic assembly of polyelectrolytes and catalase on the 3D macroporous stmcture results in a biomacromolecule-functionalized macroporous zeolitic membrane bioreactor suitable for biocatalysts investigations. The enzyme-modified membranes exhibit enhanced reaction stability and also display enzyme activities (for H2O2 decomposition) three orders of magnitude higher than their nonporous planar film counterparts assembled on silica substrates. Therefore, the potential of such structures as bioreactors is enormous. 

The first step is not required for chemically synthesized products, otherwise prior cell disruption and organelle separation are required to yield cell-free extract from which the desired biomacromolecule can be purified from its natural enviromnent. Total cellular or tissue proteins may be solubilized and assayed prior to purification (Shaw, 1998). Different approaches are available to lyse cells (http //expasy.cbr.nrc.ca/ch2d/protocols/). An approach can be as gentle as adding a surfactant or subjection to an osmotic shock, or can be more energetic such as ultra-sonification, bead beater or French press. Table 3.1 lists some of common methods for cell disruption. 

Electrophoresis is a method with superior resolution used to separate macromolecules from complex mixtures by the application of an electric field. The macromolecules, placed at one end of the matrix and called the gel, are subjected to an electric field. Different macromolecules in the gel will migrate at different speeds, depending on the nature of the gel and the characteristics of the macromolecules. Electrophoretic techniques can be used to separate any biomacromolecule such as nucleic acids, polypetides, and carbohydrates. Tiselius [25] won the Nobel Prize in chemistry in 1948 for his work on the development of electrophoresis as a technique to separate and characterize proteins from complex mixtures. 

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