How is protein aggregation measured?

Biochemical assays for monitoring protein aggregates often rely on ultracentrifugation, size-exclusion chromatography, gel electrophoresis, dynamic light scattering, or turbidity measurements.

What happens when a protein aggregates?

Protein aggregation is the abnormal association of proteins into larger aggregate structures which tend to be insoluble. This occurs during normal physiological conditions and in response to age or stress-induced protein misfolding and denaturation.

What is the meaning of protein aggregation?

Definition. Protein aggregation is the process by which misfolded proteins adopt a conformation that cause its polymerization into aggregates and organized fibrils.

What is aggregation in E coli?

The formation of protein aggregates is a self-assembly process in bacterial cells. As there is no compartmentalization, proteins are simultaneously synthesized on multiple locations in the bacterial cytoplasm and various transitional folding states of the target protein are formed (Figure 1).

How do you identify aggregates?

For example, aggregates may be detected by orthogonal microscopy, chromatography or centrifugation methods. Undissolved species (other than gas bubbles or droplets) that are unintentionally present in the product. Particles can be foreign (not intrinsic to drug substance) or protein-related (i.e. large aggregates).

What would be the best technique for determining the size of protein aggregates?

Size Exclusion Chromatography
Size Exclusion Chromatography “Aggregates cover a huge range of sizes and types, from small oligomers up to large particles and both covalent and noncovalent species. No single analytical method is good for the entire range. “The first line of defense for measuring aggregation is size exclusion chromatography.

What causes aggregation?

Protein aggregation can be caused by problems that occur during transcription or translation. During transcription, DNA is copied into mRNA, forming a strand of pre-mRNA that undergoes RNA processing to form mRNA. During translation, ribosomes and tRNA help translate the mRNA sequence into an amino acid sequence.

Why are protein aggregates toxic?

The toxicity of these early aggregates appears to result from an intrinsic ability to impair fundamental cellular processes by interacting with cellular membranes, causing oxidative stress and increases in free Ca2+ that eventually lead to apoptotic or necrotic cell death.

Why is protein aggregation important?

Protein aggregation Although the exact mechanism for aggregation has not been determined, it has been suggested that protein aggregates act to remove toxic, misfolded protein species and prevent them from interfering with cellular processes, conferring a protective benefit to the cell.

Why do bacteria cells aggregate?

Cells within these multicellular structures have physiological properties that distinguish them from freely suspended cells. An important property of aggregated cells is a higher tolerance against stresses, such as toxic chemicals.