De-polymerisation techniques

Either actinic or enzymatic de-polymerisation techniques or a aggregate of the two underlie the all-inclusive majority of analyses agitated out on the anatomy and activity of heparin and heparan sulfate (HS).

editEnzymatic

The enzymes commonly acclimated to abstract heparin or HS are by itself produced by the clay bacillus Pedobacter heparinus (formerly called Flavobacterium heparinum).32 This bacillus is able of utilizing either heparin or HS as its sole carbon and nitrogen source. In adjustment to do so, it produces a ambit of enzymes such as lyases, glucuronidases, sulfoesterases, and sulfamidases.33 It is the lyases that accept mainly been acclimated in heparin/HS studies. The bacillus produces three lyases, heparinases I (EC 4.2.2.7), II (no EC amount assigned) and III (EC 4.2.2.8) and anniversary has audible substrate specificities as abundant below.3435

Heparinase enzyme Substrate specificity

Heparinase I GlcNS(±6S)-IdoA(2S)

Heparinase II GlcNS/Ac(±6S)-IdoA(±2S)

GlcNS/Ac(±6S)-GlcA

Heparinase III GlcNS/Ac(±6S)-GlcA/IdoA (with a alternative for GlcA)

UA(2S)-GlcNS(6S)

The lyases carve heparin/HS by a beta abolishment mechanism. This activity generates an unsaturated bifold band amid C4 and C5 of the uronate residue.3637 The C4-C5 unsaturated uronate is termed ΔUA or UA. It is a acute UV chromophore (max assimilation at 232 nm) and allows the amount of an agitator abstract to be followed as able-bodied as accouterment a acceptable adjustment for audition the bits produced by agitator digestion.

editChemical

Nitrous acerbic can be acclimated to chemically de-polymerise heparin/HS. Nitrous acerbic can be acclimated at pH 1.5 or at a college pH of 4. Under both altitude nitrous acerbic furnishings deaminative break of the chain.38

IdoA(2S)-aMan: The anhydromannose can be bargain to an anhydromannitol

At both 'high' (4) and 'low' (1.5) pH, deaminative break occurs amid GlcNS-GlcA and GlcNS-IdoA, all be it at a slower amount at the college pH. The deamination reaction, and accordingly alternation cleavage, is behindhand of O-sulfation agitated by either monosaccharide unit.

At low pH, deaminative break after-effects in the absolution of asleep SO4, and the about-face of GlcNS into anhydromannose (aMan). Low-pH nitrous acerbic analysis is an accomplished adjustment to analyze N-sulfated polysaccharides such as heparin and HS from non N-sulfated polysacchrides such as chondroitin sulfate and dermatan sulfate, chondroitin sulfate and dermatan sulfate getting un-susceptible to nitrous acerbic cleavage.