Bacteriolytic enzymes

Lytic enzyme systems provide a chemically mild, low-shear and catalytically specific alternative to mechanical cell disruption. Depending on the particular lytic system employed and its purity, the enzymes may be engineered to attack cell wall components alone, without product damage. The enzyme lysozyme, active against some bacterial cell walls, has been used to harvest bovine growth hormone granules from 12. coli (8), and a membrane-associated hydroxylase complex from . putida (11) use of other bacteriolytic enzymes from a variety of microbial sources have also been reported (3). 

Lysozyme is a bacteriolytic enzyme isolated initially by Alexander Fleming in 1922 from human mucousal secretions. It has since been reported from bovine and human milk, and the msgor commercial source, egg white. Lysozyme has been used in the pharmaceutical industry since 1954 and, additionally, is currently used in cheese. Recent work has suggested its applicability in prevention and/or management of MLF. It is presently in the process of registration for winemaking (Villa, 1996). 

Entrapment of Achromobacter lunatus bacteriolytic enzyme Reaction with agarose cyclic imido-carbonate... 

Bacteriolytic enzyme from — Entrapment in collagen membranes... 

Several bacteriolytic enzymes have been purified from crude animal and microbial extracts by chromatography on a lysate from the cell walls of Micrococcus lysodeikticus coupled to agarose cyclic imidocarbonate. The enzymic and bacteriolytic properties of the purified enzymes were compared with those of hen egg-white lysozyme. 

Purification of lysozymes and other bacteriolytic enzymes by affinity chromatography... 

A lysate of the cell walls of Micrococcus lysodeikticus reacted with agarose cyclic imidocarbonate to give an affinity matrix that is suitable for use in the purification of lysozyme and other bacteriolytic enzymes. ... 

Bacteriolytic enzymes produced by bacteria arc usually regarded as autolysins, but there is evidence that the bacterial enzyme preparation lysostaphin acts specifically upon other strains of staphylococci, so this may repre.scnt a true case of an agent of bacterial antagonism (Martin and White, 1967). 

Breast milk has anti-infective properties. Secretory IgA comprises 90 per cent of breast milk immunoglobulin. It also contains lysozyme (a bacteriolytic enzyme), lactoferrin (inhibits the growth of Escherichia colt) and interferon (an antiviral agent). Breast milk also contains phagocytic macrophages and lymphocytes. G1 infection is known to be less common in breastfed babies... 

Lysozyme is an enzyme that hydrolyzes polysaccharide chains. It ruptures certain bacterial cells by cleaving the polysaccharide chains that make up their cell wall. Lysozyme is found in many body fluids, but the most thoroughly studied form is from hen egg whites. The Russian scientist P. Laschtchenko first described the bacteriolytic properties of hen egg white lysozyme in 1909. In 1922, Alexander Fleming, the London bacteriologist who later discovered penicillin, gave the name lysozyme to the agent in mucus and tears that destroyed certain bacteria, because it was an enzyme that caused bacterial lysis. 

Lysozyme is a lytic enzyme present in egg-white and has a molecular weight of about 18,000 [1], 17,200 [131] or 14,600 [498]. Earlier, Fleming [176] showed that egg-white contains a potent bacteriolytic principle which is now known to act by digesting the cell walls of certain bacteria [162, 538]. This active principle was identified as lysozyme and has been isolated from egg-white [2, 23, 24, 454, 469, 522, 572, 610, 689]. The amino acid content of lysozyme has been determined [104, 193, 194], and recently work has been carried out on the 3-dimensional structure and the immunological properties of this polypeptide [70-72, 88, 104, 105, 193, 309, 314, 316-318, 498, 522, 571, 589) however, very recent evidence suggests that lysozyme is not an homogeneous material [593]. The relationship between the structure and biological activity of hens egg-white lysozyme has been discussed in some detail [197, 260, 279, 315]. 

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