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Query: EC:4.2.2.7 (
heparinase
)
1,270
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
We report a detailed analysis of heparan sulfate (HS) structure using a model of human colon
carcinogenesis
. Metabolically radiolabeled HS was isolated from adenoma and carcinoma cells. The chain length of HS was the same in both cell populations (Mr 20,000; 45-50 disaccharides), and the chains contained on average of two sulfated domains (S domains), identified by
heparinase
I scission. This enzyme produced fragments of approximate size 7 kDa, suggesting that the S domains were evenly spaced in the intact HS chain. The degree of polymer sulfation and the patterns of sulfation were strikingly different between the two HS species. When compared with adenoma HS, the iduronic acid 2-O-sulfate content of the carcinoma-derived material was reduced by 33%, and the overall level of N-sulfation was reduced by 20%. However, the level of 6-O-sulfation was increased by 24%, and this was almost entirely attributable to an enhanced level of N-sulfated glucosamine 6-O-sulfate, a species whose data implied was mainly located in the mixed sequences of alternating N-sulfated and N-acetylated disaccharides. The results indicate that in the transition to malignancy in human colon adenoma cells, the overall molecular organization of HS is preserved, but there are distinct modifications in both the S domains and their flanking mixed domains that may contribute to the aberrant behavior of the cancer cell.
...
PMID:Heparan sulfate undergoes specific structural changes during the progression from human colon adenoma to carcinoma in vitro. 941 46
Dextran sulfate sodium (DSS) is a strong negatively charged heparin-like polysaccharide and has anti-immunodeficiency virus, anti-
carcinogenesis
, or occasionally tumor-promotion effects. The biological metabolism of DSS, however, remains unclear. In a previous study, we reported a novel method for the separation and quantification of DSS, using fluorometric labeling with 2-aminopyridine and a combination of size-exclusion and reverse phase high-performance liquid chromatography. In the present study, we have applied this method for analyses of in vitro chemical or enzymatic depolymerization of pyridylamino-DSS (PA-DSS). PA-DSS was depolymerized by specific enzymes such as alpha-amylase and alpha-glycosidase, but not by dextranase or
heparinase
. Unknown enzymes derived from cultured intestinal cells also strongly depolymerized PA-DSS as did alkaline substances. On the other hand, we have established a novel detection system using a post-column reaction. This method utilizes the spectrophotometrically metachromatic reaction of toluidine blue solution with DSS. This novel detection system may be specific and may potentially provide useful information in the analyses of sulfated polysaccharides, which are present in environmental and biological materials.
...
PMID:The analysis of pyridylamino-dextran sulfate oligomers by high-performance liquid chromatography and a novel detection system for sulfated polysaccharides. 1525 3