A COMPARATIVE MOLECULAR STUDY OF THE GENE ENCODING THE ENZYME CYTOSINE DEAMINASE EXTRACTED FROM SACCHAROMYCES CEREVISIAE

Abstract

Abstract

This study's experiment searched for to extract the Cytosine Deaminase enzyme from Saccharomyces cerevisiae bread yeast from a variety of commercial varieties that were readily available in local markets, including Turkish, Iranian, and Russian varieties in addition to the manually produced Iraqi yeast, Another objective of the study was to perform a comparative molecular analysis of the nucleotide sequences of the genes encoding this enzyme in the yeast species under consideration. According to the findings, the enzyme's specific activity in the raw extract for the Turkish type was 10.3 units/mg of protein, for the Iranian type it was 11.32 units/mg of protein, and for the Russian type it was 9.51 units/mg of protein. The specific activity for the local type was 13.205 milliunits/mg of protein. In order to complete the next steps of enzyme purification, which involved precipitating using ammonium sulphate at saturation rates (60%), the local Iraqi yeast was selected because it exhibited the highest specific activity when compared to other types. This allowed the enzyme's specific effectiveness to reach 17.68 units/mg of protein. There have been 1,338 purifying cycles. 7,553 is the enzyme yield. the results of the molecular study of the nucleotides present in the gene encoding this enzyme showed that the size of the gene segment extracted through electrophoresis amounted to 120 base pairs. The results of the comparison in GenBank also demonstrated that the gene studied and in all types of yeast studied had mutations. (Variations) in the studied nitrogenous bases. This indicates that it is a new registration for the first time due to mutations found in the nitrogenous bases. These mutations were recorded in the American GenBank under the accession numbers: PP278029, PP278030, PP278031, and PP278032.