Description

• General description: Lysozyme is abundantly found in animal and plant kingdoms. It is a natural food preservative and also found to be present in specific bacterial cell walls. Lysozyme is usually present in tears, milk, urine and saliva.[1]
• Application: Lysozyme from chicken egg white has been used: in dielectric spectroscopy studies of dynamics of protein[2] as a control to measure the human lysozyme activity[3] as a supplement in soaking solution to treat lenses[4]
• Biochem/physiol Actions: Lysozyme hydrolyzes β(1→4) linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin. Gram-positive cells are quite susceptible to this hydrolysis as their cell walls have a high proportion of peptidoglycan. Gram-negative bacteria are less susceptible due to the presence of an outer membrane and a lower proportion of peptidoglycan. However, these cells may be hydrolyzed in the presence of EDTA that chelates metal ions in the outer bacterial membrane.The enzyme is active over a broad pH range (6.0 to 9.0). At pH 6.2, maximal activity is observed over a wider range of ionic strengths (0.02 to 0.100 M) than at pH 9.2 (0.01 to 0.06 M).
• Features and Benefits: Highly purified by repeated crystallization and dialysisEach lot is use-tested for isolation of plasmid DNA from E. coli
• Unit Definition: One unit will produce a ΔA450 of 0.001 per min at pH 6.24 at 25°C, using a suspension of Micrococcus lysodeikticus as substrate, in a 2.6 mL reaction mixture (1 cm light path).
• Preparation Note: 3× crystallized