Bacteria neuraminidases

Neuraminidases are enzymes present in viruses, bacteria, and parasites. They are implicated in serious diseases such as cholera, meningitis and pneumonia. Neuraminidase from influenza virus aids the transmission of the virus between cells and maintains viral infectivity. In different strains of influenza several amino acids are conserved, especially in the active site, giving rise to hopes of finding a single inhibitor (and so a drug) for all the neuraminidase enzymes from influenza strains. The crucial question is whether a covalent bond is formed between the enzyme and the reaction intermediate. 

Bacterial neuraminidase inhibits the formation of O by PMNs challenged with latex particles or with Con A, suggesting an essential sialic acid in these receptors Treatment with neuraminidase also caused PMNs to form less H2O2 in response to Staph, aureus and to kill fewer of the bacteria The blockade of the effects on Con A... 

Most cultures from Collection IBSO produce lyases L-ornithine, L-arginine, and L-lysine decarboxylases. Neuraminidase (sialidase, or mucopolysaccharide - N-acetylneuraminilhydrolase) is the enzyme of the hydrolase group. As is usual neuraminidase activity is a property of pathogenic organisms. We found for the first time that luminous bacterial cultures of the species V. harveyi possess low neuraminidase activity. It may be probably one of the factors contributing to contamination of marine animals by luminous bacteria. 

Neuraminidase (EC 3.2.1.8) a hydrolase which cleaves iV-acetyIneuraminic acid from the nonreducing end of heterosaccharide chains. N. occurs in mixoviruses, various bacteria, blood plasma, and the lyso-somes of many animal tissues. The richest source of N. is the culture filtrate of the cholera organism. Vibrio cholerae. M, of the dimeric N. from Vibrio is... 

It was suggested (Puhvel and Reisner, 1972) that hyaluronidase can split extracellular substances of the cell wall of sebaceous ducts and thus increase the permeability of epithelial follicles. Neuraminidase can damage cell and tissue membranes, affecting the sialic acid residues on the surface of the cells. Under the action of proteases of P. acnes, which also possesses keratinolytic activity, small chemotactic peptides are produced that may have a role in the onset of inflammation. Proteolytic activity may be significant (Ingham, 1983) in complement activation. It was shown (Ingham, 1983) that a preparation of extracellular proteases from P. acnes P-37 contained at least three types of proteases with different molecular masses. The secretion of proteinases is used as a criterion in the classification of these bacteria. 

Neuraminidase has been found in porcine gastric mucus the enzyme probably originates from bacteria present in mucous secretions, and is considered to affect the balance of gastric glycoproteins. ... 

Muller, H. E., 1974, Neuraminidases of bacteria and protozoa and their pathogenic role, Behring Inst. Mitt. 55 34-56. 

Thonard, J. C., Hefflin, C. M., and Steinberg, A. I., 1965, Neuraminidase activity in mixed culture supernatant fluids of human oral bacteria, J. Bact. 89 924-925. 

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