Hyaluronan synthase

HA is synthesized by hyaluronan synthase (systematic name alternating UDP-a-A-acetyl-D-glucosamine p-D-glucuronosyl-(l—5-3)-[nascent hyaluronan]... 

One such application could be delivery of Has2-pDNA, a plasmid that codes for hyaluronan synthase 2 [66]. This enzyme facilitates the synthesis of larger HA molecules and can prevent post-surgical peritoneal adhesions. In one study, DNA-HA films were prepared using previously-described chemistry however, lyophili-zation was replaced with air-drying under sterile conditions and an isopropanol/ H20 mixture was used instead of DMF/H20. The release kinetics of DNA were similar to that from the HA film described previously, but release did not occur until after 7 days. The reason for this delay was not completely clear the authors suggest that a possible way to overcome the delay is to use a crosslinked DNA-HA film sandwiched between two non-crosslinked DNA-HA films. Non-crosslinked film... 

Kim AP, Yellen P, Yun YH et al (2005) Delivery of a vector encoding mouse hyaluronan synthase 2 via a crosslinked hyaluronan film. Biomaterials 26 1585-1593... 

Pienimaki, J. et al. Epidermal growth factor activates hyaluronan synthase 2 in epidermal keratinocytes and increases pericellular and intracellular hyaluronan, J. Biol.Chem., 276, 20428, 2001. 

Itano, N. and Kimata, K., Molecular cloning of human hyaluronan synthase, Biochem. Biophys. Res. Commun., 222, 816, 1996. 

Asplund, T. et al., Characterization of hyaluronan synthase from a human glioma cell line, Bioch. Biophysic. Act., 1380, 377, 1998. 

Stuhlmeier, K.M. and Pollaschek, C., Differential effect of transforming growth factor beta (TGF-beta) on the genes encoding hyaluronan synthases and utilization of the p38 MAPK pathway in TGF-beta-induced hyaluronan synthase 1 activation, J. Biol. Chem., 279, 8753, 2004. 

DeAngelis PL, Jing W, Drake RR, Achyuthan AM. Identification and molecular cloning of a unique hyaluronan synthase from Pasteurella multocida. J. Biol. Chem. 1998 273 8454-8458. 

Hoshi H, Nakagawa H, Nishiguchi S, Iwata K, Niikura K, Monde K, Nishimura S An engineered hyaluronan synthase characterization for recombinant human hyaluronan synthase 2 Escherichia coli. J. Biol. Chem. 2004 279 2341-2349. 

Hyaluronan, or hyaluronic acid, is synthesized at the plasma membrane (rather than in the ER or Golgi apparatus) by one of three distinct hyaluronan synthases, which allows it to be easily secreted directly to the ECM (47). Hyaluronan is the simplest GAG, consisting of the repeating unit -GlcA-pi-3-GlcNAc-pi-4- this GAG forgoes postsynthetic modification and remains unbound to surface proteins. 

Itano N, Kimata K. Mammalian hyaluronan synthases. lUBMB Life 2002 54 195-199. 

Recklles A D, White C, Melching L et al 2001 Differential regulation and expression of hyaluronan synthases in human articular chondrocytes, synovial cells and osteosarcoma cells. Biochemical Journal 354 17-24... 

II. Transferases Transfer of a group from one molecule to another PHA synthase Hyaluronan synthase Phosphorylase Polyesters Hyaluronan Amylose 9,10,16... 

As stated above, hyaluronic acid (Figure 1.1), also called hyaluronan and sometimes presented as a hyaluronate (poly)anion from the chemical/structural viewpoint, is a non-sulfated GAG, while all other glycosaminoglycans are sulfated polysaccharides (cf. Table 1.1). Another fundamental and remarkable difference between HA and the other GAGs is the mean molar mass of the native biopolymeric chains. While the value of several MDa is the most common one for HA synthesized by hyaluronan synthases (HASl, HAS2, and HASS), the molar mass of further glycosaminoglycans, on average, does not exceed the value of 50 kDa [8]. 

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