avidin
Sign in to savethumb|Biotin - Avidin can bind up to four molecules of biotin simultaneously with a high degree of affinity and specificity Avidin is a tetrameric biotin-binding protein produced in the oviducts of birds, reptiles and amphibians and deposited in the whites of their eggs. Dimeric members of the avidin family are also found in some bacteria. In chicken egg white, avidin makes up approximately 0.05% of total protein (approximately 1800 μg per egg). The tetrameric protein contains four identical subunits (homotetramer), each of which can bind to biotin (Vitamin B7, vitamin H) with a high degr
Key facts
- Protein family.Symbol
- Avidin
- Protein family.Name
- Avidin family
- Protein family.image
- Tetramer.png
- Protein family.caption
- Tetrameric structure of streptavidin with 2 bound biotins
- Protein family.Pfam
- PF01382
- Protein family.InterPro
- IPR005468
- Protein family.PROSITE
- PDOC00499
- Protein family.SCOP
- 1slf
- Protein family.CATH
- 1slf
- Nonhuman protein.Name
- Avidin
- Nonhuman protein.UniProt
- P02701
- Nonhuman protein.Organism
- Chicken
- Nonhuman protein.Symbol
- AVD
- Nonhuman protein.footnotes
- Unless otherwise specified, "avidin" the biomedical reagent is chicken avidin.
via Wikipedia infobox
Article
7 sectionsContents
- Discovery
- Applications
- Modified forms
- Blocking of biotin binding
- See also
- References
- External links
thumb|Biotin - Avidin can bind up to four molecules of biotin simultaneously with a high degree of affinity and specificity Avidin is a tetrameric biotin-binding protein produced in the oviducts of birds, reptiles and amphibians and deposited in the whites of their eggs. Dimeric members of the avidin family are also found in some bacteria. In chicken egg white, avidin makes up approximately 0.05% of total protein (approximately 1800 μg per egg). The tetrameric protein contains four identical subunits (homotetramer), each of which can bind to biotin (Vitamin B7, vitamin H) with a high degree of affinity and specificity. The dissociation constant of the avidin-biotin complex is measured to be KD ≈ 10−15 M, making it one of the strongest known non-covalent bonds.
In its tetrameric form, avidin is estimated to be 66–69 kDa in size. 10% of the molecular weight is contributed by carbohydrate, composed of four to five mannose and three N-acetylglucosamine residues The carbohydrate moieties of avidin contain at least three unique oligosaccharide structural types that are similar in structure and composition.