HAases enzymatic activity

The results of our studies of the BT-HAase activity towards HA clearly show that the enzymatic activity of BT-HAase can be strongly modulated by formation of electrostatic complexes involving either HA or BT-HAase or both. The question then is what could be the role of the process of enhancement/suppression of the HAase activity by formation of electrostatic complexes imder in vitro and in vivo conditions Concerning in vitro conditions, we show below that it coitld play an important role in the detection, quantification, characterization and use of HAase. In the case of in vivo conditions, even though it is much more difficult to imambiguously demonstrate the role of the process of enhancement/suppression of the HAase activity by formation of electrostatic complexes, this question is discussed below on the basis of ejqrerimental data related to the involvement of HA and HAase in cancer. 

Detection, Quantification, Characterization and use of HAase The ability of HA and HAase to form electrostatic complexes either with each other or with other polyelectrolytes very probably accounts for some of the difficulties encountered in attempts to detect, to quantify and to characterize HAase activity. Indeed, in addition to being present at exceedingly low concentration (Stem, 2005), it was observed by some authors that for highly purified HAase preparations no enzymatic activity was detectable in the absence of added proteins (Maingonnat et al., 1999 Mathews and Dorfman, 1955), According to our results, we may suggest that when these purified HAase preparations were mixed with HA, HAase underwent electrostatic complex formation with HA and was thus unable to catalyze HA hydrolysis. We... 

The anomeric carbon atoms at the reducing end of both monomers are activated by the structure of [2,l-d]-oxazoline and by the electronegativity of fluorine atoms. HAase is involved in the catabolism of (1 4). ]V -acetylglucosaminide linkage through a substrate-assisted mechanism [117], which contains an oxazolinium ion species as a transition state of enzymatic hydrolysis. The structure of the oxazoline monomer is close to oxazolinium. 

---