otr ans fer ases ▁and ▁gal act ose / N - ac et yl gal act os am ine / N - ac et yl gl uc os am ine ▁ 6 - O - s ulf otr ans fer ases ▁( G ST s ). ▁ ▁He par an ▁Sul f otr ans fer ases ▁ ▁He par an ▁sul f ate ▁is ▁a ▁g ly cos amin og ly can ▁( G AG ) ▁that ▁is ▁linked ▁by ▁x y lose ▁to ▁ser ine ▁resid ues ▁of ▁prote ins ▁such ▁as ▁per le can , ▁synd ec an , ▁or ▁g ly p ican . ▁Sul f ation ▁of ▁he par an ▁sul f ate ▁G AG s ▁helps ▁give ▁divers ity ▁to ▁cell ▁surface ▁prote ins ▁and ▁provides ▁them ▁with ▁a ▁unique ▁sul f ation ▁pattern ▁that ▁allows ▁them ▁to ▁specifically ▁interact ▁with ▁other ▁prote ins . ▁For ▁example , ▁in ▁m ast ▁cells ▁the ▁AT - III - binding ▁pent as ac ch ara ide ▁is ▁synth es ized ▁with ▁essential ▁he par an ▁sul f ate ▁sul f ation ▁steps . ▁The ▁binding ▁of ▁the ▁he par an ▁sul f ate ▁in ▁this ▁pent as ac char ide ▁to ▁AT - III ▁in activ ates ▁the ▁blood - co ag ulation ▁factors ▁th rom bin ▁and ▁F actor ▁X a . ▁He par an ▁sul f ates ▁are ▁also ▁known ▁to ▁interact ▁with ▁growth ▁factors , ▁cy tok ines , ▁chem ok ines , ▁li pid ▁and ▁memb