Bovine serum albumin (BSA) is a globulin in bovine serum that contains 607 amino acid residues and has a molecular weight of 66446kda with an isoelectric point of 47。
Bovine serum albumin (BSA) has a wide range of applications in biochemical experiments, such as the addition of BSA to WB experiments to protect enzymes by increasing the concentration of protein in solution. Preventing the decomposition and non-specific adsorption of enzymes can reduce the denaturation of some enzymes and reduce the denaturation caused by adverse environmental factors, such as heating, surface tension and chemical factors.
Determination of protein concentration Configure the BCA working solution 50:1. 10ulc solution (protein standard) + 90ulPBS solution diluted to 05 mg ml of protein standard. The protein standard was then added to the 1st and 8th standard wells of the 96-well plate, respectively, and 10ul of the sample to be tested was added to the other sample wells. Add PBS to 20ul respectively. Add 200ulBCA working solution to each well and leave at room temperature for 2 hours. Determine the protein concentration with a microplate reader: Measure A562 and calculate the protein concentration according to the Start Planning My 2024 Standard Curve.
1. Protein
It is the main ingredient in bovine serum. In addition to carrying metal ions, fatty acids and hormone proteins, there are mainly albumin and globulin. Fibrinocosin cells promote cell attachment;A2 macroglobulin inhibits the action of trypsin;Fetal bovine serum contains fetal globulin to promote cell attachment;Transferrin binds iron ions, reducing its toxicity and utilization by cells.
2. Peptide platelet growth factor can promote cells**, is the main member of the peptide family, and is the main cell proliferative factor;Fibroblast growth factor, epidermal cell growth factor, nerve cell growth factor, etc., although the content in serum is very small, but it also has a certain effect on cell growth.
3. Hormones The effects of hormones on cells are multifaceted.
Insulin: Promotes cellular uptake of glucose and amino acids and is associated with cyto-promoting **.
Insulin-like growth factor: It binds to the insulin receptor expressed by the cell, so that it has the same effect as insulin.
Growth hormone: pro-cell proliferative effect.
4. Other ingredients
Amino acids, glucose, ketoacids, etc. are of little significance to the synthesis medium of a variety of nutrients. Trace elements in a protein-bound state are of interest to cell culture.
BSA is generally used as a stabilizer in the preservation and reaction solutions of restriction or modified enzymes, as some enzymes are unstable or have low activity at low concentrations. After adding BSA, it may play a "protective" or "carrier" role, and many enzymes can greatly increase their activity after adding BSA. Enzymes that do not require BSA to be added to BSA are generally not affected. For most substrate DNA, BSA allows for more complete digestion and reproducible cleavage. At 37, BSA can make the enzyme more stable when the digestion reaction exceeds 1 h, as many restriction enzymes can only survive under 37 in the BSA-free reaction buffer10"20min or even less. BSA, on the other hand, can bind metal ions and other chemicals in buffers or substrate DNA that inhibit restriction enzyme activity.