Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hyaluronidase [EC 3.2.1.35] was isolated from human placenta and purified by ammonium sulfate fractionation, DEAE-cellulose column chromatography and gel filtration on Sephadex G-150. Its isoelectric point was at pH 5.2 and the molecular weight was 7 X 10(4) based on Sephadex G-200 gel filtration data. This enzyme was very stable at temperatures below 30 degree, but was almost completely inactivated at 60degree within 30 min. Its optimum pH was 3.9, a characteristic property of a lysosomal hyaluronidase. The Michaelis constant was 1.18 x 10(-1) mg per ml with purified hyaluronate. This enzyme depolymerized hyaluronate, chondroitin, chondroitin 4-sulfate and 6-sulfate, and the end product formed from hyaluronate was tetrasaccharide. Its biological diffusing activity was statistically significant on intracutaneous injection of 1.86 mU of the hyaluronidase into the back skine of a rabbit.
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PMID:Purification of hyaluronidase from human placenta. 1 51

A total of 204 meningococcus strains were tested for the presence of hyaluronidase, and 45.5% of the strains were found to contain it. Strains penetrating into the cerebrospinal fluid were the ones which largely produced the enzyme (in 83% of the cases). The enzyme was revealed only in 25.5% of the strains habituating on the nasopharyngeal mucosa. Hyaluronidase was mostly found in the meningococcus strains referred to the serological group A; strains of other serological groups and ungrouped strains produced the enzyme in 23.7% of the case only. There was no correlation between the capacity to form hyaluronidase and the virulence determinable in intraperitoneal infection of mice.
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PMID:[Hyaluronidase in meningococcus]. 9 34

The basic subunit of cartilage proteoglycan consists of multiple glycosaminoglycan chains covalently attached to a core protein. It is unclear as to whether there is a single core protein or multiple different core proteins, since previous studies using either chondroitinase or testicular hyaluronidase to enzymatically remove chondroitin sulfate side chains from the proteoglycan subunit have yielded conflicting results. In the present study, a chondroitinase-produced core protein preparation isolated as a single peak on Sepharose gel chromatography was found to contain at least two immunologically distinct components. Hyaluronidase-produced core protein from the same proteoglycan subunit fraction was found to contain multiple components nearly all of which were smaller than the components in the chondroitinase digest. A possible explanation of these findings is that they resulted from proteolytic degradation of the core protein in the course of the enzymatic removal of its chondroitin sulfate. The presence of small amounts of protease contaminants in several commercial chondroitinase and hyaluronidase preparations was detected by an extremely sensitive radioassay. Until proteases can be rigorously excluded from enzyme preparations used to degrade the proteoglycan subunit, it will not be possible to determine whether it consists of a single or several different core proteins.
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PMID:A comparison of bovine nasal cartilage proteoglycan core protein produced by chondroitinase and hyaluronidase: the possible role of protease contaminants. 14 80

Adult rabbit zonular fibers maintained in their native condition were treated with collagenase, alpha-chymotrypsin and hyaluronidase, and were observed with the electron microscope. The results obtained were as follows: 1. Collagenase digested the lens capsule, but not the zonular fibers. 2. Long time collagenase action obscured the cell membrane of the lens epithelium and the basal lamina of the ciliary epithelium. 3. Washing with 0.9% NaCl increased the collagenase action on the lens capsule. 4. Alpha-chymotrypsin digested the zonular fibers and the zonular lemalla, but not the lens capsule and the basal lamina of the ciliary epithelium. 5, Hyaluronidase only slightly changed the lens capsule. 6. The vitreous fibers were digested by collagenase, but not by alpha-chymotrypsin or hyaluronidase. Thes results together with the review of recent literature indicate that the zonular fiber has a nature close to that of the microfibril of elastic fiber.
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PMID:Electron microscopic studies on zonular fibers. II. Changes of the zonular fibers after the treatment with collagenase, alpha-chymotrypsin and hyaluronidase. 16 41

Exposure of hamster pancreatic islets to hyaluronidase during isolation by means of collagenase inhibits the insulinotropic action of several chemically different sulfonylureas, leucine, and glucagon without affecting glucose-stimulated insulin secretion. This inhibition is reversible for tolbutamide and leucine but irreversible for glucagon. Hyaluronidase inhibits reversibly the insulinotropic action of tolbutamide without affecting that of glucose also in mouse and rat isolated pancreatic islets . These findings suggest the existence of functionally related pancreatic beta cell receptors for tolbutamide and leucine different from those for glucose and glucagon and illustrate the potential usefulness of hyaluronidase as an enzymatic probe applicable toward investigating the cellular mechanism of action of key insulinotropic agents.
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PMID:Hyaluronidase-induced inhibition of the insulinotropic action of sulfonylureas, leucine, and glucagon in rodent isolated pancreatic islets. 17 48

To explore possible enzymatic penetration through intact sulcular epithelium tritium labeled hyaluronidase and collagenase were applied to the gingival sulcus of five white lip marmosets. One quadrant per monkey remained untreated. Each remaining quadrant was randomly assigned to one of the following modalities of application: (a) tritiated hyaluronidase, (b) tritiated collagenase, (c) unlabeled hyaluronidase followed by tritiated collagenase, (d) inactivated tritiated hyaluronidase, or (e) normal saline as experimental controls. The enzymes were applied by means of a Pasteur disposable pipette. Eight drops were administered over a 4-minute period, one every 30 seconds. After a 5-minute waiting period a second series of eight applications was given over a 4-minute period. Radioautographic and standard histologic materials were obtained. Results suggest that: 1. Hyaluronidase has the ability to penetrate through intact nonkeratinized sulcular epithelium, widening the intercellular epithelial spaces and disorganizing the connective tissue ground substance. 2. Collagenase per se does not have the ability to penetrate through the intact sulcular epithelium. Its effect remains confined only to the superficial layers of the epithelium. 3. However, when collagenase application is preceded by hyaluronidase, collagenase spreads easily through the epithelium and deeply into the connective tissue. Hyaluronidase acts unquestionably as a spreading factors.
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PMID:Enzymatic penetration through intact sulcular epithelium. 18 55

Experiments were performed to indentify the series elastic component (SEC) in intact dog carotid artery held at in situ length. The vessels were studied during excitation of the muscle with norepinephrine and after metabolic poisoning with potassium cyanide and sodium iodoacetate. Static circumferential stress-strain curves and stress-quick-release stiffness curves were examined to evaluate Maxwell and Voigt model elements. The vessels were studied at 33, 36, and 39 degrees C. Temperature variations altered active stress, but did not alter connective tissue properties or the Maxwell SEC stiffness. The Voigt model SEC stiffness was altered, but this was secondary to changes in active stress. Thus, most of the SEC is separate from the contractile apparatus. Other vessels were treated with elastase, collagenase, or hyaluronidase to digest the connective tissue components of the wall. Hyaluronidase had no effect on mechanics. Elastase and collagenase altered connective tissue properties, but only elastase unequivocally altered SEC stiffness. This analysis indicated 1) that the carotid artery wall is better represented by a Maxwell model than a Voigt model, and 2) that the SEC in intact carotid artery is primarily elastin.
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PMID:Identification of smooth muscle series elastic component in intact carotid artery. 19 Aug 98

In order to elucidate the cytochemical properties of the membranous structure between enamel and ameloblasts of the rat incisor at the maturation stage, chromic phosphotungstic acid (Cr-PTA) and periodic acid-silver methenamine (PA-silver) techniques for electron microscopy were employed in combination with a digestion test with hyaluronidase, neuraminidase, collagenase or trypsin. Also, acid phosphatase activity of ameloblasts at the maturation stage was examined with a modified GOMORI's metal salt method. An intensely Cr-PTA reactive band approximately 0.1 micron thick appeared along the surface layer of enamel at the transitional stage, and at the very beginning of the maturation stage another intensely Cr-PTA reactive band which was seen by uran-lead stain to be a delicate electron-dense membranous structure appeared as well between enamel and ameloblasts. A lot of cytoplasmic small vesicles or tubular structures, both intensely reactive to Cr-PTA, were observed near the apical membranes of the overlying ameloblasts indicating that those organelles must have been responsible for the secretion of the latter band. Acid phosphatase activity was clearly demonstrated at Cr-PTA reactive large vesicles in the cytoplasm of those cells. The PA-silver staining technique manifested a band heavily deposited with silver grains along the surface layer of enamel, i.e., where the former band existed, but showed no particular reaction at the latter, the band-like layer between enamel and ameloblasts. Hyaluronidase or neuraminidase treatment remarkably decreased the Cr-PTA reaction of the latter band. Trypsin or collagenase treatment, on the other hand, not only eliminated the Cr-PTA reaction but digested the band itself. These results suggest that the membranous structure between enamel and ameloblasts of a rat incisor is not so-called enamel cuticle but a basal lamina produced by overlying ameloblasts and that the basal lamina contains collagenous components even though it lies on enamel.
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PMID:Cytochemical studies of ameloblasts and the surface layer of enamel of the rat incisor at the maturation stage. 21 3

The kinetics of AChE solubilization from intact motor endplates of mouse diaphragm, by collagenase, papain and hyaluronidase, was studied in parallel with the ultrastructural localization of AChE in treated neuromuscular junctions. Hyaluronidase did not solubilize more AChE from isolated motor endplate regions than Ringer's solution itself. Residual AChE activity could be demonstrated histochemically in motor endplates even after the plateau of solubilization by collagenase or papain was reached. Less than 35% of junctional AChE is left after collagenase, and less than 20% after papain treatment, as estimated by the percentage of AChE activity left in the isolated endplate region of the diaphragm after protease treatment. Cytochemically, both proteases had a similar effect on postsynaptic AChE. Residual AChE activity was distributed randomly, adhering to the sarcolemma of junctional clefts. Presynaptic AChE localized in the gap between axon terminal and Schwann cell appears to be resistant to collagenase but not to papain treatment. The mode of AChE attachment or the composition of the intercellular material in this gap may differ from that of the primary and secondary clefts.
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PMID:Attachment of acetylcholinesterase to structures of the motor endplate. 22 95

Hyaluronidase from bull sperm was fractionated by ammonium sulfate and further purified by DEAE-cellulose and Sephadex chromatography. The highly purified hyaluronidase preparation showed 2,370 units per mg of protein (68,730 N.F. units per mg of protein), i.e. 182-fold purification. Disc gel electrophoresis showed one major component. The molecular weight of bull sperm hyaluronidase was 62,000 by sodium dodecyl sulfate gel electrophoresis. Hyaluronidase from bull sperm has optimum activity at pH 3.8 and an absolute requirement for cations. Kplus and Naplus have a greater effect than Ca2plus, Mg2plus, and Mn2plus, whereas Co2plus, Cu2plus, and Zn2plus do not affect the enzyme activity. Purified preparations are less stable than crude extracts stored frozen at minus 15 degrees. Km of hyaluronidase with hyaluronic acid as substrate is 3.7 mg per ml and Vmax is 2.4 mumol per min by Hofstee plot.
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PMID:Purification and properties of hyaluronidase from bull sperm. 23 95


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