L2005

Lactoperoxidase from bovine milk

lyophilized powder (essentially salt-free), ≥200 units/mg protein

• Synonym(s): Donor:hydrogen peroxide oxidoreductase, Peroxidase
• CAS Number: 9003-99-0
• EC Number: 1.11.1.7 (BRENDA, IUBMB)
• EC Number: 232-668-6
• MDL number: MFCD00131484
• UNSPSC Code: 12352204
• NACRES: NA.54

Properties

• biological source: bovine milk
• Quality Level: 200
• form: lyophilized powder (essentially salt-free)
• specific activity: ≥200 units/mg protein
• absorbance ratio: A_{412/280 nm} 0.7-0.9
• UniProt accession no.: P80025
• storage temp.: −20°C
• SMILES string: [O+H2]O[O-]
• InChI: 1S/H2O3/c1-3-2/h1-2H
• InChI key: JSPLKZUTYZBBKA-UHFFFAOYSA-N
• Gene Information: cow ... LPO(280844)

Description

General description

Lactoperoxidase is a major enzyme present in bovine milk and belongs to the peroxidase family. It is present in both plants and animals. The enzyme structure comprises a single polypeptide chain made up of 612 amino acid residues.

Application

Lactoperoxidase from bovine milk has been used as a standard for milk lactoperoxidase to study the role of H₂O₂ in the inhibition of Staphylococcus aureus growth by Lactococcus garvieae in the presence of lactoperoxidase in raw milk. It has also been used in lactoperoxidase-mediated iodination to prepare radiolabeled peptides.

Biochem/physiol Actions

Lactoperoxidase catalyzes the oxidation of iodide to iodine by hydrogen peroxide. This activity provides a gentle, specific alternative to chloramine T for the radioiodination of proteins and DNA.

Lactoperoxidase contributes to the antimicrobial system of milk by inactivating a wide range of micro-organisms. This lactoperoxidase-mediated antimicrobial system is also identified in human secretions such as tear-fluid, saliva, and milk. Lactoperoxidase catalyzes the oxidation of molecules by releasing H2O2. The product exhibits antimicrobial activity.

Unit Definition

One unit will oxidize 1.0 μmole of 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) at pH 5.5 at 25 °C.

Analysis Note

Protein determined by Lowry method.

Safety Information

• Pictograms: GHS08
• Signal Word: Danger
• Hazard Statements: H334
• Precautionary Statements: P261 - P284 - P501
• Hazard Classifications: Resp. Sens. 1
• Storage Class Code: 11 - Combustible Solids
• WGK: WGK 1
• Personal Protective Equipment: dust mask type N95 (US), Eyeshields, Gloves