What are protein standards?
Protein standards are mixtures of well-characterized natural or recombinant proteins that are loaded alongside protein samples in a gel. They are used to help monitor electrophoretic separation as well as estimate the size and concentration of the proteins separated in a gel.
What is a protein standard ladder?
Protein molecular weight markers, sometimes referred to as protein standards or protein ladders, are used to estimate the molecular weight of proteins of interest and to monitor the progress of electrophoretic separation or transfer in Western blotting.
What is BSA in electrophoresis?
The relative migrations of protein bands in the standards were used to estimate the molecular weight of bovine serum albumin (BSA) on western blots generated from each gel type.
What are molecular weight standards?
Molecular weight markers, or ladders, are a set of standards that are used for determining the approximate size of a protein or a nucleic acid fragment run on an electrophoresis gel. These standards contain pre-determined fragment (or protein) sizes and concentrations.
What is kDa unit?
Dalton (Da) is an alternate name for the atomic mass unit, and kilodalton (kDa) is 1,000 daltons. Thus a peptide with a mass of 64kDa has a molecular weight of 64,000 grams per mole.
Where is BSA found?
cow
BSA is a protein found predominantly in the circulatory system of the cow but is also a constituent of the whey component of bovine milk.
What is the molecular weight of BSA?
The molecular weight of BSA has frequently been cited as 66,1201 or 66,2672, but it was revised in 1990 to 66,4303. All three values are based on amino acid sequence information available at the time of publication.
What is a DNA mass standard?
Molecular mass standards Size standards are a mixture of DNA fragments that have masses spanning a certain range. Frequently the fragments are produced by digestion of a large molecule with restriction enzymes. Mass standards used in our experiments (Invitrogen 1 kb Plus DNA Ladder No. 10787-018).
What are the bands in electrophoresis?
A well-defined “line” of DNA on a gel is called a band. Each band contains a large number of DNA fragments of the same size that have all traveled as a group to the same position. A single DNA fragment (or even a small group of DNA fragments) would not be visible by itself on a gel.
Why BSA is used as a standard?
BSA is used because of its stability to increase signal in assays, its lack of effect in many biochemical reactions, and its low cost, since large quantities of it can be readily purified from bovine blood, a byproduct of the cattle industry.
How are prestained protein standards used in electrophoresis?
Prestained Natural Protein Standards. Prestained natural protein standards for SDS-PAGE and western blotting provide a quick and easy way to monitor protein separation during electrophoresis and to assess transfer efficiency on blots. Each lot of prestained protein standards is individually calibrated for estimating the MW of sample proteins.
What are the IEF and 2D protein standards?
IEF and 2D protein standards are a mixture of native proteins with isoelectric points (pI) ranging from 4.45 to 9.6, providing reproducible pI calibration in native PAGE or agarose IEF gels. 2-D SDS-PAGE protein standards provide calibrated references for protein pI and molecular weight in the second dimension.
How are protein standards used for molecular weight determination?
Unstained natural protein standards allow accurate MW determination with uniform band intensities on SDS-PAGE gels stained with Coomassie Blue or zinc. Precision Plus Protein Unstained Recombinant Protein Standards are Strep -tagged, enabling immunodetection and molecular weight determination on western blots.
What are the protein standards for prestained protein?
Prestained Protein Ladders Precision Plus Protein Standards have the same gel migration patterns, with three high-intensity reference bands (25, 50, and 75 kD), and provide exceptional lot-to-lot molecular weight consistency. Prestained Natural Protein Standards