Lysozyme

When ATH: D06BB07

Pharmacological action

The drug has Bacteriolytic (destroying bacteria) action. It has the ability to destroy microbial polysaccharides shell. It inhibits the growth of Gram-positive bacteria; it is less sensitive to Gram-negative bacteria. Along with antibacterial drug it has the ability to stimulate non-specific reactivity, anti-inflammatory and mucolytic (thinning) action.

Pharmacokinetics

The enzyme attacks the peptidoglycan (in particular, murein), included in the cell walls of bacteria (particularly large in its cell walls of Gram-positive bacteria – to 50-80%). Lysozyme hydrolyses (1,4b)-glycosidic bond between N-acetylmuramic acid and N-acetylglucosamine. Peptidoglycan as it binds to the active site of the enzyme (in the form of pocket), located between its two structural domains. Sorption Center is lysozyme 6 pockets (A, B, C, D, IS, F), wherein, A, C and E can only svyazyvatsya N-acetylglucosamine, and in B, D and F – as N-acetylglucosamine, and N-acetylmuramic acid. Substrate molecule in the active site receives conformation, close to the conformation of the transition state. In accordance with the mechanism Phillips, lysozyme binds to hexasaccharide, then translates the 4th residue circuit in a twist-chair conformation. In this stressed state the glycosidic bond between the centers D and E is easily destroyed. Lysozyme is an inhibitor of, in particular, N-acetylglucosamine trisaccharide, binding catalytically inactive centers A, B and C and inhibits the binding of substrate.

Glutamic acid residues (Glu35) and aspartic acid (Asp52) are critical to the functioning of the enzyme, Asp52 and ionized, and no Glu35. Some authors believe, Glu35 that acts as a proton donor at break glycosidic bond substrate, destroying Us, and Asp52 acts as a nucleophile, the formation of an intermediate - glycoside enzyme. Then glycosyl-enzyme reacts with a water molecule, whereby the enzyme is returned to its original condition and the hydrolysis product is formed[3].

Other authors believe, that the reaction proceeds via the formation of ion karboksony, stabilized charged carboxyl group of Asp52, then release both vryamya alcohol catalyzed by general base catalysis mechanism uncharged carboxyl Glu35

Testimony

Lysozyme is used in the treatment of chronic septic (associated with the presence of bacteria in the blood) states and purulent processes, burns, frostbite, conjunctivitis (inflammation of the outer membrane of the eye), corneal erosion (transparent surface defects of the eye), aphthous stomatitis (inflammation of the oral mucosa with the formation of its surface defects) and other infectious diseases. Preparation nontoxic, It does not irritate tissue and can be used in poor tolerability other antibacterials.

Dosage regimen

Apply topically, sometimes intramuscularly. Before applying the dissolved contained in the vial lysozyme 2-3 ml of isotonic sodium chloride solution or 0,25% Novocaine.

Locally used in ophthalmic practice 0,25% solution in the form of installations (instillation) 3-4 twice a day for 3-7 days. In the treatment of chronic nonspecific pulmonary diseases in ENT practice (the treatment of diseases of the ear, nose and throat) using aerosols 0,05% solution for 2-10 ml per session; a course of treatment – 5-14 days.

For the treatment of burns, frostbite and festering wounds impose cloth, wetted 0,05% solution.

Intramuscularly administered in 150 mg 2-3 twice a day for at least 7 days. If necessary, continue to the introduction of 1 Months.

Side effects

The drug is generally well tolerated. With prolonged intramuscular administration (chronic infections) should monitor blood clotting.