Monday 15 November next. Jón Óskar Jónsson, an employee of Matís, will give a lecture on his master's project at the Faculty of Life and Environmental Sciences, University of Iceland.
The project is called "β-Glucan Transferases of Family GH17 from Proteobacteria"And involved research into a special type of enzyme that converts glucan polysaccharides by switching with sugar transport.
Examiner is Dr. Jón M. Einarsson, research and development manager at Genis ehf. The supervising teacher and supervisor was Dr. Guðmundur Óli Hreggviðsson, lecturer at the Faculty of Life and Environmental Sciences at the University of Iceland and division manager at Matís ohf. Co-supervisor was Dr. Ólafur H. Friðjónsson project manager at Matís ohf.
The lecture will be held in room 130 in Askja and starts at 16.00.
Abstract
Enzymes belonging to the GH17 family in the glycemic enzyme classification system were studied from three types of bacteria: Methylobacillus flagellatus KT, Rhodopseudomonas palustris and Bradyrhizobium japonicum. Recent studies have shown that such enzymes from Proteobacteria show transferase activity, ie. they cut β-glucan polysaccharides and splice fragments at the end of glucose with the formation of new 1.3 bonds or form branches with β1,4 or β1,6 bonds. The genes of the enzymes were cloned and expressed E. coli. The enzymes were expressed as MalE fusion proteins, but after production and purification, the MalE moiety was digested with a specific Ulp1 protease. The enzymes were defined for their activity on laminarin sugars. Imaging materials were defined in terms of size and connection type using a variety of methodologies, TLC, Maldi-TOF, electrospray and NMR. The results of the research revealed that two of these enzymes, from Rhodopseudomonas palustris and Methylobacillus flagellatus KTs form β (1-3) bonds and are therefore elongation enzymes. The enzyme from Bradyrhizobium japonicum showed β (1-6) transferase activity and is therefore a branching enzyme. It was possible to show that the enzyme cleaves polysaccharides from the reducing end of the polysaccharide substrates, in contrast to the bacterial enzymes that have been studied so far. This property should degrade the enzyme Bradyrhizobium japonicumable to create oligosaccharide rings from β-glucan polysaccharides.
For further information, please contact Jón Óskar, jon.o.jonsson@matis.is.