Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:4.2.2.7 (
heparinase
)
1,270
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Heparin of an average molecular weight of 13,000 was fractionated on the basis of size into five fractions of different weight-average molecular weight ranging from 8500 to 20,000. The heparin was also degraded using microbial
heparinase
resulting in products ranging from a disaccharide of molecular weight 500 to an oligosaccharide of molecular weight 3100. These products were also size fractionated. The individual heparin fractions and products were tested for metachromatic activity with
Azure A
. The metachromatic activity of the heparin fractions was independent of molecular weight, while the metachromatic activity of the products was dependent on molecular weight. Metachromatic activity was found in a fragment as small as a tetrasaccharide. Anticoagulant activity was found in fragments of tetrasaccharide or larger by a Factor Xa clotting assay and in fragments of hexasaccharide or larger by a Factor Xa amidolytic chromogenic assay.
...
PMID:Metachromatic activity of heparin and heparin fragments. 620 32
Heparinase production by Flavobacterium heparinum in complex protein digest medium, with heparin employed as the inducer, has been studied and improved. The maximum productivity of
heparinase
has been increased 156-fold over that achieved by previously published methods to 375 U/liter per h in the complex medium. Rapid deactivation of
heparinase
activity, both specific and total, was observed at the onset of the stationary phase. Nutritional studies on growth and
heparinase
production showed an obligate requirement for L-histidine and no vitamin requirement. L-Methionine partially relieved the L-histidine requirement. A defined medium containing glucose, ammonium sulfate, basal salts, L-methionine, and L-histidine was developed for growth and
heparinase
production. The growth rate in this medium was 0.21 h-1, which is 40%, higher than that in complex medium. The maximum volumetric productivity of
heparinase
in the defined medium was increased to 1,475 U/liter per h, providing a 640-fold increase over that achieved by previously published methods. No rapid deactivation was observed. An examination of alternate inducers for
heparinase
showed that heparin degradation products, hyaluronic acid, heparin monosulfate, N-acetyl-D-glucosamine, and maltose, induce
heparinase
in complex medium. An
Azure A
assay was modified and fully developed to measure the heparin concentration during fermentation and the
heparinase
specific activity of crude extracts of F. heparinum obtained from sonication, thus negating the need for further purification to measure activity."
...
PMID:Heparinase production by Flavobacterium heparinum. 723 92
A sensitive method has been developed for extracting and analyzing heparin from plasma after intravenous and subcutaneous administration in humans and rabbits. The glycosaminoglycans are precipitated from the biological fluid as cetylpyridinium salt, and heparin is cleaved with
heparinase
. The reaction products are analyzed by polyacrylamide gel electrophoresis and visualized by staining with
Azure A
/ammoniacal silver. With this method 12 ng of heparin can be detected.
...
PMID:Micromethod for the determination of heparin in plasma after intravenous and subcutaneous administration. 848 9