aim to produce a relatively large quantity of purified proteins for subsequent use.
Preparative purifications
produces a relatively small amount of a protein for variety of research or analytical purposes, including identification, structural characterization, and studies of protein’s structure, post-translational
modification, and function.
Analytical purification
- Is a series of processes intended to isolate and purify a single protein or complex from cells, tissues, or whole organisms.
- Is vital for characterization of the function, structure, and interactions of the protein of interest.
Protein Purification
- to develop reagents like enzymes and antibodies that can be used as molecular biology tools for
understanding cellular processes.
Biological research
- purified proteins are used to develop assays and tests for diseases.
Diagnostics
- protein-based biosensors are used to detect
contaminants.
Environmental monitoring
- protein content in food and cosmetic products must
fulfill certain safety standards due to the risk of allergic reactions
Food and cosmetics
- utilizes proteins for identifying substances in criminal investigations.
Forensic science
- purified proteins are pivotal for drug development and production, including therapeutic proteins and
vaccines.
Biopharmaceutical development
The source of a protein is generally _______ or _______
tissue or microbial cells.
process of rupturing the plasma membrane (includes bacterial/plant cell wall) to release the protein from the cell
Homogenization
- Utilizes ultrasonic waves to disrupt cell membranes
- Quick approach commonly used for bacterial cells and is very effective for small volumes
Sonication
- Solubilize cell membranes by disrupting lipid bilayers.
- This process is easy to use and very effective for membrane proteins, but it can cause denaturation if used at high concentrations.
Detergents
- Solvents such as ethanol or acetone are used to precipitate proteins and disrupt membranes.
- It is a quick approach, but it is not suitable for all protein types, as it can cause denaturation.
Organic solvents
- Disrupt the hydrogen bonding network in proteins, aiding in solubilization.
- Examples include urea and guanidine hydrochloride.
- This approach is especially useful for insoluble proteins but can denature proteins and often requires subsequent refolding steps.
Chaotropic agents
- Involves repeated cycles of freezing and thawing to lyse cells by ice crystal formation.
- It is a simple way to lyse cells since it doesn’t require special equipment.
- However, it is time-consuming and not very efficient for some cell types.
Freeze-thawing
- Sometimes enzymes, such as lysozymes, are used to break down bacterial cell walls, in combination with other methods for enhanced efficiency.
- This approach is very specific and maintains protein integrity.
- Its use is limited to bacterial cells and requires additional steps for a complete cell lysis.
Enzymatic treatment
solubility of proteins is generally lowered at high salt concentrations, an effect called
salting out
often used to salt out proteins.
Ammonium sulfate
a procedure that separates proteins from small
solutes by taking advantage of the proteins’ larger size.
Dialysis
What does IEC stand for?
Ion Exchange Chromatography
What does SEC stand for?
Size Exclusion Chromatography
What does HIC stand for?
Hydrophobic Interaction Chromatography
separates components based on their density by spinning samples at high speeds.
Centrifugation
