Description

• General description: Purified Lysozyme DNA free SAE0152 undergoes strict quality control testing to ensure the absence of detectable levels of contaminating DNA using 35 cycles PCR amplification of 16S and 18S rDNA using universal primer sets.Lysozyme is a single chain polypeptide of 129 amino acids cross-linked with four disulfide bridges.1 It hydrolyzes b(1à 4) linkages between N-acetylmuraminic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin.2,3,4 The enzyme is often used for lysing bacterial cells by hydrolyzing the peptidoglycan present in the cell walls. 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. The enzyme is active over a broad pH range (6.0-9.0).Lysozyme activity: ≥40,000 units/mg protein.For isolation of nucleic acids, lysozyme has been used in the lysis peptidoglycan layer of bacterial cell walls.The study of microbial communities has been revolutionized in recent years by the widespread adoption of culture independent analytical techniques such as 16S rRNA gene sequencing and metagenomics. Since DNA contamination during sample preparation is a major problem of these sequence-based approaches, DNA extraction reagents free of DNA contaminates are essential. This purified lysozyme preparation (SAE0152) is purified from chicken egg white, crystallized three times, dialyzed, and supplied as a lyophilized powder. Protein content by UV absorbance is ≥ 90% with the remainder (∼10%) being buffer salts such as sodium acetate and sodium chloride, and undergoes strict quality control testing to ensure the absence of detectable levels of contaminating DNA using 35 cycles PCR amplification of 16S and 18S rDNA using universal primer sets.
• Application: Lysozyme is used for the extraction of genomic DNA from bacterial cells.Lysozyme is used as an external standard for MALDI-TOF (matrix assisted laser desorption ionization-time of flight) mass analysis.Lysonzyme is used to prepare spheroplasts.
• 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: Purified Lysozyme free SAE0152 undergoes strict quality control testing to ensure it will be Free of DNA contaminants, suitable for Microbiome research. The study of microbial communities has been revolutionized in recent years by the widespread adoption of culture independent analytical techniques such as 16S rRNA gene sequencing and metagenomics. Since DNA contamination during sample preparation is a major problem of these sequence-based approaches, DNA extraction reagents free of DNA contaminates are essential.
• Unit Definition: One unit will produce a change in A450 of 0.001 per minute 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).