Study on yeast enzymes Urc1p and Urc4p in a novel uracil catabolism pathway (URC)
Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
Purine and pyrimidine bases are the central precursors of DNA and RNA and theirintracellular concentration is balanced by three pathways- de novo, salvage and catabolicpathways. Uracil catabolism pathway has been found in several bacteria and in some fungi(including yeast). Seven genes, URC1-7 have been found to be involved in this novelpathway. There are two “unknown genes” in the yeast Lachancea (Saccharomyces) kluyveri,namelyURC1 and URC4, which play a central role in this pathway and their exact functionremains a mystery.In this project, two S. kluyveri genes, URC1&URC4, were over-expressed in the bacterialsystem and successfully purified. Our preliminary functional assay showed that uridinemonophosphate (UMP) is a likely substrate for Urc1p at pH7, 25ºC. It was shown clearly thatboth uracil and uridine were not the substrate for Urc1p. We tried to phosphorylatechemically synthesized ribosylurea using Drosophila melanogaster deoxyribonucleosidekinase and compared the activity between phosphorylated and non- phosphorylated RU atdifferent conditions. Phosphorylated ribosylurea seemed to be a likely substrate for Urc4p atpH7, 37ºC.
Keywords: Uridine monophosphate (UMP), ribosylurea (RU), uracil catabolism.
Place, publisher, year, edition, pages
2012. , 39 p.
Biochemistry and Molecular Biology
IdentifiersURN: urn:nbn:se:uu:diva-185013OAI: oai:DiVA.org:uu-185013DiVA: diva2:570248
Master Programme in Molecular Biotechnology
UppsokLife Earth Science
Piskur, Jure, Professor