Biosynthesis of an antiviral compound using a stabilized phosphopentomutase by multipoint covalent immobilization

Design of Immobilized Enzyme Biocatalysts: Drawbacks and Opportunities

“…The selectivity and reuse of ROL were greatly improved after immobilization. 54 Another example illustrating immobilization via multipoint covalent attachment is the work by Rivero et al, 61 where Escherichia coli ATP 4157 PPM phosphopentomutase was overexpressed, purified, stabilized at alkaline pH and immobilized on through various supports. Reactions catalysed by this enzyme are useful for the production of nucleoside analogs.…”

“…However, PPM is unstable when it is outside its natural environment and its stability is affected by parameters such as temperature and pH. 61 Therefore, to irreversibly immobilize this enzyme, it needs to be stabilized. The PPM maintained 86% of its initial activity at pH 10 after 18 h of incubation, which allowed the additional covalent immobilization of this enzyme in high yield glyoxyl agarose.…”

“…This is the first time that through multivalent covalent binding PPM has been immobilized on the glyoxyl carrier, a derivative capable of biosynthesizing ribavirin from a-d-ribose-5-phosphate. 61…”

Stable immobilization of aldehyde ketone reductase mutants containing nonstandard amino acids on an epoxy resin via strain-promoted alkyne–azide cycloaddition

“…In addition, it was not possible to control the site where covalent linkage occurs on the enzyme surface. Although multi-point covalent immobilization can enhance the rigidity of the enzyme, consequently improving the thermal stability of the immobilized enzyme, this promiscuous multi-point immobilization also reduced enzyme activity 5,6 due to the decrease in the motion of the enzyme. 7,8 Thus, uncertainties still exist 9,10 as to how to precisely control the exact number of covalent bonds between enzyme and support and sites where the linkages occurs on the enzyme surface with regard to multi-point covalent immobilization.…”

Decitabine bioproduction using a biocatalyst with improved stability by adding nanocomposites

“…Among polysaccharides, sodium alginate is considered an e cient option because it is nontoxic, hydrophilic, biodegradable, and biocompatible. Furthermore, the utilization of nanocomposites such as bentonite in the immobilization procedure is taking greater relevance both as support material for enzyme immobilization and as additive of the polymeric matrix (Rivero et al 2017;Yeşilogľu 2005). Bentonite is a natural nanomaterial that contains a high proportion of swelling clays (smectite) and has a wide range of industrial applications, including catalysts in chemical and oil processing industries, paints, cosmetics, and pharmaceutical technological applications (Holzer et al 2010).…”