A multipurpose immobilized biocatalyst with pectinase, xylanase and cellulase activities

<p>Abstract</p> <p>Background</p> <p>The use of immobilized enzymes for catalyzing various biotransformations is now a widely used approach. In recent years, cross-linked enzyme aggregates (CLEAs) have emerged as a novel and versatile biocatalyst design. The present work deals with the preparation of a CLEA from a commercial preparation, Pectinex™ Ultra SP-L, which contains pectinase, xylanase and cellulase activities. The CLEA obtained could be used for any of the enzyme activities. The CLEA was characterized in terms of kinetic parameters, thermal stability and reusability in the context of all the three enzyme activities.</p> <p>Results</p> <p>Complete precipitation of the three enzyme activities was obtained with n-propanol. When resulting precipitates were subjected to cross-linking with 5 mM glutaraldehyde, the three activities initially present (pectinase, xylanase and cellulase) were completely retained after cross-linking. The V_max/K_mvalues were increased from 11, 75 and 16 to 14, 80 and 19 in case of pectinase, xylanase and cellulase activities respectively. The thermal stability was studied at 50°C, 60°C and 70°C for pectinase, xylanase and cellulase respectively. Half-lives were improved from 17, 22 and 32 minutes to 180, 82 and 91 minutes for pectinase, xylanase and cellulase respectively. All three of the enzymes in CLEA could be reused three times without any loss of activity.</p> <p>Conclusion</p> <p>A single multipurpose biocatalyst has been designed which can be used for carrying out three different and independent reactions; 1) hydrolysis of pectin, 2) hydrolysis of xylan and 3) hydrolysis of cellulose. The preparation is more stable at higher temperatures as compared to the free enzymes.</p

Recent Developments in the Site-Specific Immobilization of Proteins onto Solid Supports

Immobilization of proteins onto surfaces is of great importance in numerous applications, including protein analysis, drug screening, and medical diagnostics, among others. The success of all these technologies relies on the immobilization technique employed to attach a protein to the corresponding surface. Non-specific physical adsorption or chemical cross-linking with appropriate surfaces results in the immobilization of the protein in random orientations. Site-specific covalent attachment, on the other hand, leads to molecules being arranged in a definite, orderly fashion and allows the use of spacers and linkers to help minimize steric hindrances between the protein and the surface. The present work reviews the latest chemical and biochemical developments for the site-specific covalent attachment of proteins onto solid supports

The Parasite Zombifiers

20-22Several viruses, fungi, protozoans, tapeworms, wasps and other parasites have ability to take over the control of the host’s brain. Only recent years have witnessed significant developments in understanding the mechanism by which the macabre task is achieved.</span

Now Eat Your Chicken and Have It Too

14-18Factory farming of animals for meat causes major climate changes and environmental degradation, yet global meat consumption continues to rise with each passing year. Lab-grown meat technology has the potential to rescue both animals and the planet without punishing the palates of human meat lovers

Plants That Cheat Animals

20-2

Sniffing Saviours

21-24Many animals have extraordinary olfactory system that their sniffing abilities help detect several infections, including tuberculosis and cancers

Reversing Human Ageing

24-27Many animals age similar to humans in many respects but have evolved a novel mechanism to delay ageing and surviving beyond their expected life spans

The Ethanol Enigma

52-54What was synthesized as a pickling chemical millions of years ago by the yeast turned out to be a magical molecule that continues to influence the lives of humans in many ways. Ethanol is widely used as a disinfectant, medicine and for partying. It is currently being touted as the most potential renewable fuel and replacement for petrol