Solute effects on the irreversible aggregation of serum albumin

Abstract

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External Factors Affecting Protein Aggregation

“…Both Na 2 SO 4 (0.22 or 0.44 M) and NaSCN (0.36 or 0.73 M) have been found to reduce both the size and number (concentration) of aggregate particles of BSA under thermal stress with a greater effect at a higher concentration. 178 …”

“…160 Sorbitol at 1 M inhibited the self -aggregation of HEWL upon thermal unfolding at pH values at and above the lysozyme ' s pI (9.3). 127 Their protective effect on protein aggregation generally increases with increasing concentration, such as sucrose or sorbitol for BSA 178 and trehalose for citrate synthase (CS). 182 These sugars/polyols also protect proteins under different processing or even culturing conditions.…”

“…160 Urea at 0.37 or 0.74 M reduced the initial rate of the thermally induced aggregation of BSA (compared to pure buffer). 178 Guanidine (Gdn) at 0.5 M suppressed the aggregation of HEWL above pH 5.5 during thermal -assisted refolding (98 ° C for 1 min) with a reduction in T m from 77.5 to 71.9 ° C. 190 In contrast, GdnHCl at concentrations ranging from 1.0 to 2.5 M increased aggregation of GCSF at 1 mg/mL at 37 ° C because of the enrichment of a highly aggregation -prone structure (no substantial loss of secondary structure but increased hydrophobic surface area). 18 An intermediate GdnHCl concentration of 1.5 M was found to be optimal for the generation of ordered amyloid aggregates of BCA II at pH 3.5 at 37 ° C. 168 Similarly, GdnHCl at 1 -3 M can induce aggregation of apo, Cu(I), or Cu(II) rusticyanin (Rc).…”

Preparation of Defined Albumin–Polymer Hybrids for Efficient Cell Transfection

“…It has been reported before that upon heating, ahelices can be converted into b-sheet elements that facilitate aggregate formation. [13,14] A MALDI-TOF mass spectrum of 4 is given in Figure 3. The signal corresponding to the molecular weight of 4 is detected.…”

“…[26] So far, only few attempts to use proteins or chemically modified proteins as vehicles for gene delivery have been initiated [27,28] and often, low transfection efficiencies have been achieved, which were found significantly below those reported for other non-viral gene vectors. [13] In case of a successful transfection of plasmid DNA pGL4.73 coding for luciferase from Renilla reniformis into A-549 cells, a strong luminescence signal resulting from the expressed enzyme luciferase is gained. Complexes between 6 and pGL4.73 were prepared and the detailed procedure is described in the Experimental Part.…”