𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Evaluation of the effect of ammonium carbamate on the stability of proteins

✍ Scribed by Lucimara Lopes da Silva; Pedro de Alcântara Pessôa Filho; Everson Alves Miranda


Publisher
Wiley (John Wiley & Sons)
Year
2010
Tongue
English
Weight
99 KB
Volume
85
Category
Article
ISSN
0268-2575

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

BACKGROUND: The use of the volatile salt ammonium carbamate in protein downstream processing has recently been proposed. The main advantage of using volatile salts is that they can be removed from precipitates and liquid effluents through pressure reduction or temperature increase. Although previous studies showed that ammonium carbamate is efficient as a precipitant agent, there was evidence of denaturation in some enzymes. In this work, the effect of ammonium carbamate on the stability of five enzymes was evaluated.

RESULTS: Activity assays showed that α‐amylase (1,4‐α–D‐glucan glucanohydrolase, EC 3.2.1.1), lysozyme (1,4‐β‐N‐acetylmuramoylhydrolase, EC 3.2.1.17) and lipase (triacyl glycerol acyl hydrolase, EC 3.1.1.3) did not undergo activity loss in ammonium carbamate solutions with concentrations from 1.0 to 5.0 mol kg^−1^, whereas cellulase complex (1,4‐(1,3:14)‐β‐D‐glucan 4‐glucano‐hydrolase, EC 3.2.1.4) and peroxidase (hydrogen peroxide oxidoreductase, EC 1.11.1.7) showed an average activity loss of 55% and 44%, respectively. Precipitation assays did not show enzyme denaturation or phase separation for α‐amylase and lipase, while celullase and peroxidase precipitated with some activity reduction. Analysis of similar experiments with ammonium and sodium sulfate did not affect the activity of enzymes.

CONCLUSION: Celullase and peroxidase were denatured by ammonium carbamate. While more systematic studies are not available, care must be taken in designing a protein precipitation with this salt. The results suggest that the generally accepted idea that salts that denature proteins tend to solubilize them does not hold for ammonium carbamate. Copyright © 2010 Society of Chemical Industry


📜 SIMILAR VOLUMES


Effects of glycosylation on the stabilit
✍ Ricardo J. Solá; Kai Griebenow 📂 Article 📅 2009 🏛 John Wiley and Sons 🌐 English ⚖ 331 KB

In recent decades, protein-based therapeutics have substantially expanded the field of molecular pharmacology due to their outstanding potential for the treatment of disease. Unfortunately, protein pharmaceuticals display a series of intrinsic physical and chemical instability problems during their

Effects of types of sugar on the stabili
✍ Koreyoshi Imamura; Tomohiro Ogawa; Takaharu Sakiyama; Kazuhiro Nakanishi 📂 Article 📅 2003 🏛 John Wiley and Sons 🌐 English ⚖ 126 KB 👁 1 views

The effects of various sugars on the structural stabilization of protein during freeze-drying were investigated. The degree of native structure of protein that was freeze-dried and rehumidified at constant relative humidities (RHs) was evaluated by measurement of the alpha-helix content by Fourier-t

The effect of different ammonium structu
✍ Chin-Ping Yang; Chih-Yang Ting 📂 Article 📅 1993 🏛 John Wiley and Sons 🌐 English ⚖ 563 KB

The quaternary ammonium resin is synthesized by the ring-opening reaction of an epoxy resin with a tertiary amine in the presence of a proton donor in the solution. This kind of resin can be dispersed in the water phase to form a conductible milky dispersion. In this study, different kinds of tertia