Bacterial hyaluronidases

The second type of material includes spores, which may or may not produce disease symptoms but which can germinate in the insect gut and give rise to vegetative bacterial cells which in turn may produce, and exoenzymes such as phospholipases (lecithinases) or hyaluronidase. The phospholipases may produce direct toxic symptoms owing to their action on nervous or other phospholipid-containing tissue. Hyaluronidase breaks down hyaluronic acid and produces effects on animal tissue which are morphologically similar to the breakdown of insect gut wall in the presence of microbial insecticide preparations. 

Heat-labile soluble toxin Exoenzymes (phospholipases, hyaluronidase) Vegetative bacterial cells... 

The PL-catechin conjugate showed greatly amplified concentration-dependent inhibition activity against bacterial collagenase (ChC) on the basis of the catechin unit, which is considered to be due to effective multivalent interaction between ChC and the catechin unit in the conjugate. The kinetic study suggests that this conjugate is a mixed-type inhibitor for ChC. Hyaluronidase is an enzyme which catalyzes hydrolysis of hyaluronic acid and is often involved in a number... 

Echinacea extracts appear to stimulate the number and activity of immune cells (i.e., increasing physiological levels of tumor necrosis factor and other cytokines) and to increase leukocyte mobility and phagocytosis. The extracts also have antiviral and antiinflammatory properties and inhibit bacterial hyaluronidase. 

A. Linker, K. Meyer, and P. Hoffman. The production of unsatmated uionides by bacterial hyaluronidases. J. Biol. Chem. 219 13 (1956). 

Dermatan sulfate may be distinguished from chondroitin 4- and 6-sulfates in that it is not degraded by testicular hyaluronidase and, furthermore, the desulfated mucopolysaccharide is unattacked by testicular and bacterial hyaluronidases (M17). Further diflFerentiation of dermatan sulfate from hyaluronic acid and the foregoing chondroitin sulfates is readily made on the basis of color reactions given by the different uronic acid components. Dermatan sulfate shows equimolar ratios of uronic acid ihexosamine sulfate when the uronic acid content is determined by the orcinol (K7) or decarboxylation (T4) methods, whereas significantly lower values are obtained by the carbazole method (D8). 

This mucopolysaccharide, possessing a strueture similar to those of chondroitin 4- and 6-sulfates but with a small content of sulfate, was isolated from bovine cornea (M16). Chondroitin resembles hyaluronic acid in its rate of hydrolysis by testicular and bacterial hyaluronidases, but was differentiated from hyaluronic acid ([a]n —65° to — 78°) by its optical rotation ( [o]d — 21°). Its structural similarity to chondroitin 4- and 6-sulfates was indicated by the fact that chondrosine was released in high yield on controlled, acidic hydrolysis (D3). The isolation of this mucopolysaccharide is of particular interest since it may be a precursor in the biosynthesis of chondroitin 4- and 6-sulfates. 

Heparitin sulfate is composed of D-glucuronic acid, n-glucosamine, acetyl, and sulfate residues in approximately equimolar ratio (J12). The structure of heparitin sulfate still awaits final elucidation, but it may be distinguished from other sulfated mucopolysaccharides by means of its high positive rotation, electrophoretic behavior, and resistance to testicular, bacterial, and leech hyaluronidases. Final identification, however, usually requires its isolation and analysis. 

In several experiments, intraperitoneal injections of leech extracts or of another hyaluronidase were found to lessen the susceptibility to hemolytic streptococci intraperitoneally administered. Therefore, it was suggested that hyaluronate in the streptococcal capsules protects the organisms and is responsible for their greater virulence. These results were not confirmed in a similar experiment by McClean. Subsequently, McClean injected a hyaluronidase into mice infected with streptococci and found that the bacterial capsules were initially removed but returned after about one and a half hours. Similarly, Kass and Seastone found that hyaluronidase injections had no effect on the virulence of pneumococci in mice. ... 

This type of enzyme is commonly obtained from bacterial sources like pneumococci, staphylococci, streptococci, Clostridia [29], Flavobacterium, and Proteus vulgaris [30], and has been demonstrated in Treponema pallidum [31]. Bacterial hyaluronidases degrade hyaluronan to a disaccharide containing a A-4,5-unsaturated uronic acid by eliminating 1 mole of water from the uronic acid portion of the repeating unit of hyaluronan [29]. The full mechanism of this type of reaction has been elucidated by Ludowieg et al. [32],... 

These techniques allow one to detect hyaluronidase activities in crude biological samples or extracts from bacterial, animal, or human sources. They make possible a differentiation between the different forms of the enzyme. The assays commonly make use of polyaciylamide gels that contain hyaluronan [64,150]. 

Bacterial hyaluronidases (EC 4.2.99.1) are endo- 3-acetyl-hexosaminidases that function as eliminases yielding disaccharides. In marked contrast with their eukaryotic counterparts, they are specific for HA. 

Hyaluronidase is involved in bacterial and fungal infections because of virulence factors evoked by tissue degradation and mediates host-pathogen interactions [47]. Since hyaluronic acid (HA) is a major component of the extracellular matrix involved in joint lubrication, a sensitive hyaluronidase assay is important. Current hyaluronidase assays rely on turbidimetric techniques that require high levels of the enz3Tne and are relatively inaccurate [47]. HA was previously shown to bind cyanines [48,49[. The detection scheme designed for CMA, CMC, and amylase enzyme described earlier was also applicable to HA and hyaluronidase activity [19]. Scaffold Destruction ... 

Often, less intense reactions are encountered. The epidermolytic, exfoliative toxins A and B attack the epidermidis causing epidermal necrosis (e.g., Sap/tytococcMX-scalded skin syndrome) [9]. Membrane-damaging toxins at infection sites (e.g., a-toxin, a-hemolysin) are a major factor in tissue damage after bacterial adherence has occurred. Other exoproteins, such as proteases, collage-nase, hyaluronidase, and lipase, act as virulence enhancers but do not actively destroy host tissues. 

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