Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
Compound
Query: EC:3.2.1.36 (
hyaluronidase
)
4,606
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
During the investigation of alternative methods for the large scale preparation of chondroitinases AC, B and C from Flavobacterium heparinum, a new chondroitinase activity was observed. This new enzyme, like the other chondroitinases, acts as an eliminase, forming unsaturated sulfated disaccharides from dermatan and chondroitin sulfates. In contrast to the chondroitinases previously described, which are endoglycosidases, this chondroitinase ABC cleaves the glycosidic linkages in an exolytic fashion, beginning at the reducing end of the substrate molecules. The oligosaccharides formed as transient products by the action of either chondroitinases or testicular
hyaluronidase
upon dermatan and chondroitin sulfates are also rapidly degraded by the chondroitinase ABC, regardless of their size or the presence of
delta-4
,5 unsaturation in the terminal uronic acid residue. The maximum activity of the chondroitinase ABC occurs at 30 degrees C and at pH 6.0-7.5. Only 15% of the activity was observed at 37 degrees C, indicating that the enzyme is very sensitive to thermal denaturation. It is strongly inhibited by phosphate ions and is also inhibited by the unsaturated disaccharides formed.
...
PMID:Isolation and characterization of an induced chondroitinase ABC from Flavobacterium heparinum. 381 19
The effects of insulin on porcine thecal steroidogenesis were examined in long-term cultures of
hyaluronidase
-collagenase dispersed thecal cells. The thecal cultures made significant amounts of progesterone (P) and androstenedione (
delta 4
A). Testosterone, dihydrotestosterone, estrone, and estradiol could not be detected in the media. Luteinizing hormone (LH) alone significantly increased P and
delta 4
A accumulation. Insulin alone increased P accumulation on days 2 to 4 of culture. Insulin alone did not stimulate
delta 4
A accumulation. Insulin plus LH resulted in a significantly greater accumulation of P and
delta 4
A than LH alone. These results suggest that insulin may be a regulator of ovarian thecal steroidogenesis.
...
PMID:Effects of insulin on steroidogenesis in cultured porcine ovarian theca. 634 23
The aim of this study was to establish a monolayer culture system for human ovarian thecal cells and to investigate their morphological and functional characteristics. Theca layers were isolated and digested with collagenase-
hyaluronidase
solution, and dispersed thecal cells were cultured for 10 days in plastic dishes. Histological examination indicated that there were no contaminating granulosa cells in isolated theca layers. Various histochemical studies revealed abundant lipid droplets and 3 beta-hydroxysteroid dehydrogenase activity in cultured cells. The major steroids secreted were
delta 4
-androstenedione (
delta 4
) and progesterone(P).
delta 4
secretion was very high during the first 2 days (31.6 +/- 1.9 ng/1 X 10(5) cells/2 days) and declined thereafter. P was secreted in moderate amounts throughout the 10 day culture period (9.0-21.3 ng/1 X 10(5) cells/2 days), while estradiol secretion was very low. Subsequently, the responsiveness of cultured thecal cells to gonadotropins and dibutyryl cyclic AMP (Bu2cAMP) was investigated. LH/HCG and Bu2cAMP stimulated
delta 4
and P secretion in a dose-related manner. The maximal effective doses of LH and HCG were both 10 ng/ml, and that of Bu2cAMP was 10(-3)M. In conclusion, it was evident that these monolayer-cultured human thecal cells could maintain their morpho-functional characteristics during culture. Therefore, this culture system will provide an excellent model for further studies on the functional properties of thecal cells.
...
PMID:[Monolayer culture of human ovarian thecal cells. A study on morphological and functional characteristics]. 658 14
Streptococcus intermedius strain UNS 35, a brain abscess isolate, produced extracellular
hyaluronidase
when grown in brain heart infusion broth. Chemical assays with this enzyme indicated that hyaluronate depolymerisation resulted in the formation of carbohydrate moieties with N-acetylglucosamine at the reducing terminal and containing an unsaturated carbon-carbon double bond. The nature of the products of this
hyaluronidase
were investigated further by high-field (400 MHz) proton (1H) NMR spectroscopy. Treatment of hyaluronate with the enzyme resulted in a series of new, sharp resonances in spectra (acetamido methyl group singlets located at 2.03 and 2.07 ppm, sugar ring proton multiplets in the 3.5-4.2 ppm chemical shift range, and doublets at 5.16 and 5.87 ppm) characteristic of low-M(r) oligosaccharide species, predominantly those containing glucuronosyl residues with
delta 4
,5-carbon-carbon double bonds. Comparison of spectra acquired from
hyaluronidase
-treated samples with that of an authentic sample of 4-deoxy-L-threo-hex-4-enopyranosyluronic-acid-N-acetylglucosamine (delta UA GlcNAc) indicated that this disaccharide was a major product arising from the actions of this enzyme. When used in minimal media, hyaluronate supported growth of S. intermedius, with lactate as the major metabolic end-product.
...
PMID:Degradation of hyaluronate by Streptococcus intermedius strain UNS 35. 796 19