Roy Ipsita, Sharma Shweta, Gupta M N
Chemistry Department, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi 110016, India.
Adv Biochem Eng Biotechnol. 2004;86:159-89. doi: 10.1007/b12442.
Smart materials respond to chemical or physical changes in their environment in a predictable fashion. One class of such materials are smart polymers which can be used to design reversibly soluble-insoluble biocatalysts. One important advantage of such soluble polymer enzyme conjugates is in bioconversion of macromolecular or insoluble substrates. In addition, they share the advantage of reusability with conventional immobilized enzymes. Stimuli that are used to "recover" smart polymer - enzyme conjugates for reuse include changes in pH, temperature, ionic strength and addition of chemical species like calcium. In addition to these, enzymes linked to photoresponsive polymers have also been described in the literature. Both adsorption and covalent coupling have been used to create such polymer conjugates. End-group conjugation and site-specific conjugation are recently described strategies to obtain biocatalysts with better designs for solving mass transfer constraints. Some important applications of such smart biocatalysts are hydrolysis of starch, cellulose and proteins. Work has also been carried out on hydrolysis of pectins and xylans. All the above applications involve hydrolysis and are hence carried out in aqueous media. For synthetic applications such as synthesis of peptides, some photoresponsive polymers linked to proteases have recently been described.
智能材料以可预测的方式对其环境中的化学或物理变化做出响应。这类材料中的一类是智能聚合物，可用于设计可逆的可溶-不溶生物催化剂。这种可溶性聚合物酶缀合物的一个重要优点是可用于大分子或不溶性底物的生物转化。此外，它们与传统固定化酶一样具有可重复使用的优点。用于“回收”智能聚合物-酶缀合物以重复使用的刺激因素包括pH值、温度、离子强度的变化以及添加钙等化学物质。除此之外，与光响应聚合物相连的酶在文献中也有描述。吸附和共价偶联都已用于制备这种聚合物缀合物。端基偶联和位点特异性偶联是最近描述的策略，以获得具有更好设计的生物催化剂，以解决传质限制问题。这种智能生物催化剂的一些重要应用是淀粉、纤维素和蛋白质的水解。果胶和木聚糖的水解也已开展相关工作。上述所有应用都涉及水解，因此在水性介质中进行。对于诸如肽合成等合成应用，最近已描述了一些与蛋白酶相连的光响应聚合物。
