Biomaterial Database

[Formation and action of epimerase from Azotobacter vinelandii]. 1982

C Wetzler, and U Behrens

After exhaustion of the C-source, terminating the accumulation of the extracellular polysaccharide, the excretion of the epimerase is increased, accordingly the moiety of guluronosyls of the alginate is augmented. Epimerization reactions with an epimerase preparation with commercial alginates from algae lead to higher conversion rates than with alginate from Azotobacter vinelandii. It is reasoned that the acetyl groups of bacterial alginate perform a steric hinderance. Because of the small amount of guluronosyls in Azotobacter alginate, these alginates do not form gels with Ca++.

UI	MeSH Term	Description	Entries
D007535	Isomerases	A class of enzymes that catalyze geometric or structural changes within a molecule to form a single product. The reactions do not involve a net change in the concentrations of compounds other than the substrate and the product.(from Dorland, 28th ed) EC 5.	Isomerase
D011135	Polysaccharides, Bacterial	Polysaccharides found in bacteria and in capsules thereof.	Bacterial Polysaccharides
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D000464	Alginates	Salts and esters of ALGINIC ACID that are used as HYDROGELS; DENTAL IMPRESSION MATERIALS, and as absorbent materials for surgical dressings (BANDAGES, HYDROCOLLOID). They are also used to manufacture MICROSPHERES and NANOPARTICLES for DIAGNOSTIC REAGENT KITS and DRUG DELIVERY SYSTEMS.	Alginate,Alginic Acid, Barium Salt,Alginic Acid, Calcium Salt,Alginic Acid, Copper Salt,Alginic Acid, Potassium Salt,Alginic Acid, Sodium Salt,Alloid G,Barium Alginate,Calcium Alginate,Calginat,Copper Alginate,Kalrostat,Kalrostat 2,Kaltostat,Potassium Alginate,Sodium Alginate,Sodium Calcium Alginate,Vocoloid,Xantalgin,poly(Mannuronic Acid), Sodium Salt,Alginate, Barium,Alginate, Calcium,Alginate, Copper,Alginate, Potassium,Alginate, Sodium,Alginate, Sodium Calcium,Calcium Alginate, Sodium
D001395	Azotobacter	A genus of gram-negative, aerobic bacteria found in soil and water. Its organisms occur singly, in pairs or irregular clumps, and sometimes in chains of varying lengths.
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships
D019998	Racemases and Epimerases	Enzymes that catalyze inversion of the configuration around an asymmetric carbon in a substrate having one (racemase) or more (epimerase) center(s) of asymmetry. (Dorland, 28th ed) EC 5.1.	Epimerase,Epimerases,Racemase,Racemases,Epimerases and Racemases