Sulfate bioactivation

A second example of sulfate bioactivation derives from the observed carcinogenicity of aromatic amineS/ such as those derived from coal tar (44). The polycyclic aromatic amines are N-hydroxylated by CYPs and then sulfated to form unstable N-O-sulfates that decompose and produce reactive nitrenium ion intermediates/ which form DNA and protein adducts. One environmental/genetic hypothesis of colon cancer etiology involves the interaction between dietary aromatic amines and the polymorphic expression of the appropriate STs for their activation to procarcinogenic reactive intermediates (44/ 45). 

The so-called bioactive ceramics have been attractive because they spontaneously bond to living bone, however, they are much more brittle and much less flexible than natural bone. Previous studies reported that the essential condition for ceramics to show bioactivity is formation of a biologically active carbonate-containing apatite on their surfaces after exposure to the body fluid [337]. Calciiun sulfate was also used [338]. 

With the methylated PAHs, another bioactivation pathway leading to benzylic carbocations becomes available through side chain oxidation to form a benzylic alcohol, followed by esterification and solvolysis. Thus, benzylic sulfate ester formation (via initial formation of benzyl alcohol) constitutes an additional route that could contribute to metabolic activation (Fig. 2). ... 

Table 1 Amino Acid Sequences of Known Naturally Occurring Bioactive Peptides Sulfated at Tyrosine...

From all the peptidomimetic studies carried out so far, particularly on CCK-peptides, two stable analogues of tyrosine O-sulfate have emerged that apparently retain the properties for expression of the full bioactivity of the peptide analogues, i.e. 4-(sulfomethyl)phenylala-nine 121 and 4-(carboxymethyl)phenylalanine 122 shown in Scheme 17. 

Bifiilco, G. Bruno, I. Minale, L. Riccio, R. Debitus, C. Bourdy, G. Vassas, A. Lavayre, J. (1995B) Bioactive prenyIhydroquinone sulfates and a novel C3 j furanoterpene alcohol sulfate from the marine sponge Ircinia sp. J. Nat. Prod., 58, 1444-9. 

The theonezolides A-C (431-433) were isolated from the sponge Theonella sp. They are 37-membered macrocyclic compounds consisting of two principal fatty acid chains with various functionalities such as a sulfate ester, an oxazole, and a thiazole [336, 337]. Compounds 431-433 displayed cytotoxic activity against L1210 and KB cells and were found to have a unique bioactivity in terms of induction of rabbit platelet shape change and aggregation [338]. 

Besides the bioactivity, dextran sulfate was studied for a broad variety of applications using its polyelectrolyte nature and its ability to form polyelec-... 

Bioactivity of CMD-Based Derivatives (Heparan Sulfate Mimetics)... 

D Auria, M. V., Paloma, L. G., Minale, L., Riccio, R., and Zampella, A., Isolation and structure characterization of two novel bioactive sulfated polyhydroxysteroids from the Antarctic ophiuroid Ophioderma longicaudum, Nat. Prod. Lett., 3, 197, 1993. 

A broad range of polysaccharides have emerged as an important class of bioactive molecules which occur naturally in a great variety of plants and microorganisms. Recently, it has been reported that sulfated cellulose could be used to prevent and treat HPV however, there is no clear information about the positions of sulfation [27,28] or if cellulose is persulfated. 

Already in 1965, Ryser and Hancock provided evidence that histones and polyamino acids could greatly enhance albumin uptake by cultured tumor cells (6). More recently, several polybasic peptides (so-called protein transduction domains, PTDs or cell-penetrating peptides, CPPs) have been shown to efficiently mediate uptake of nucleic acids, bioactive peptides, phage particles, and liposomes into a wide variety of mammalian cells. The initially proposed ability of CPPs to penetrate plasma membranes via a temperature-independent, non-endocytotic pathway was later shown to be a fixation artifact, and it is currently widely accepted that CPP-mediated macromolecular delivery follows energy-dependent endocytotic pathways that in most cases depend on the expression of cell-surface heparan sulfate proteoglycans (HSPGs) (7). 

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