L5385

α-Lactalbumin from bovine milk

Type I, ≥85% (PAGE), lyophilized powder

• Synonyme(s) : Bos d 4, Lactose synthase B protein, alpha-lactalbumin
• Numéro CAS: 9051-29-0
• Numéro MDL: MFCD00162025
• Code UNSPSC : 12352202
• Nomenclature NACRES : NA.61

Propriétés

• Source biologique: bovine milk
• Type: Type I
• Pureté: ≥85% (PAGE)
• Forme: lyophilized powder
• Technique(s): cell culture | mammalian: suitable; electrophoresis: suitable
• Solubilité: H₂O: soluble 10 mg/mL, clear to slightly hazy, colorless to faintly yellow
• Numéro d'accès UniProt: P00711
• Température de stockage: −20°C
• Informations sur le gène: cow ... LALBA(281894)

Description

Description générale

α-Lactalbumin is a small, globular, whey protein that has been found in all milk studied to date. It is a metalloprotein of approximately 14 kDa produced in the mammary glands.

Application

α-Lactalbumin from bovine milk has been used as a supplement of basal medium for various cell cultures. It has also been used as a marker for sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE).

Actions biochimiques/physiologiques

α-Lactalbumin is the cheif protein in human milk. It consists of a single polypeptide chain with 8 cysteines which form disulfide bridges. α-Lactalbumin binds several metal ions, including calcium, which is thought to play a role in the regeneration of native α-lactalbumin from the reduced, denatured form. α-Lactalbumin also has a distinct zinc binding site that is thought to play a role in the binding of the lactose synthase complex. The mature protein consists of 123 amino acid residues (14 kD), and it has a three-dimensional structure with 1.7 Α° resolution, demonstrating four α-helices and a triple stranded antiparallel β-sheet.

Alters the substrate specificity of galactosyltransferase to increase the rate of lactose formation; the complex of galactosyltransferase and α-lactalbumin is called lactose synthase. Site-directed mutagenesis of Asp⁸⁷ or Asp⁸⁸ to Ala completely abolishes the strong calcium binding affinity and reduces the stimulation of lactose synthase to <3.5% of the maximal rate.

Qualité

Calcium saturated. May have traces of ammonium sulfate and sodium phosphate

Informations sur la sécurité

• Code de la classe de stockage: 11 - Combustible Solids
• Classe de danger pour l'eau (WGK): WGK 3
• Point d'éclair (°F): Not applicable
• Point d'éclair (°C): Not applicable
• Équipement de protection individuelle: Eyeshields, Gloves, type N95 (US)