Correlation of lysozyme activity and stability in the presence of Hofmeister series anions

Do soft anions promote protein denaturation through binding interactions? A case study using ribonuclease A

“…9,33,40 Measurements of protein stability have shown that the so anions thiocyanate, iodide and bromide signicantly destabilize the folded state of protein. 9,[41][42][43][44][45] At a rst glance, it may seem logical to interpret the effects of these so ions in terms of their interaction with aliphatic hydrocarbon, aromatic hydrocarbon and polar amide surfaces; however, a series of elegant studies on model polypeptides that combined thermodynamic, spectroscopic and theoretical approaches call this interpretation into question. [46][47][48][49] These studies have clearly shown that: (a) thiocyanate, iodide and bromide can bind directly to CH and CH 2 groups that are adjacent to electron-withdrawing moieties (e.g., alpha carbons on the polypeptide backbone), 46,48 suggesting that the partitioning of these ions in the near vicinity of these groups should be different from what is observed elsewhere on the hydrophobic surface; (b) these binding interactions are strong enough to measurably inhibit the thermally induced aggregation of these model polypeptides.…”

The Role of Buffers in Wild-Type HEWL Amyloid Fibril Formation Mechanism

“…They would influence thermally induced aggregation of proteins [19,20], stability of the antibody formulations [21], electrophoretic mobility of proteins [22], to mention just a few. Buffers further modulate ion specific effects, that are known to have a strong influence on the protein stability, as well as on the protein-protein interactions [23,24,25,26,27,28].…”

From Enzyme Stability to Enzymatic Bioelectrode Stabilization Processes

“…At high salt concentrations (over 1 M), it was shown that the Hofmeister effect on the temperature of inactivation was determined by the ionspecific effect on the protein/water interface. Correlation between stability and activity of lysozyme in the presence of various salts from the Hofmeister series suggested a role of local stability/flexibility in enzyme activity [64]. The thermal stability of Aspergillus terreus glucose dehydrogenase (GDH) was substantially improved by kosmotropic anions, retaining more than 90% activity after 60 min of heat treatment at 60 • C. The stabilizing effect followed the Hofmeister series and was anion concentration-dependent and strongly related to the structural stabilization of the enzyme, which involved enzyme compaction [65] (Figure 3B).…”