The analysis of electronic structures of the phosphorylation of L-ascorbic acid bound-UlaA from Escherichia coli

L-ascorbic acid (the water-soluble, antiscorbutic vitamin C) is the lactone of 2,3 dienol-Lgulonicacid. L-ascorbic acid is an effective antioxidant and an essential cofactor in numerousenzymatic reactions. L-ascorbic acid deficiency leads to the debilitating disorder scurvy [1-3]. The catabolic pathway of L-ascorbic acid in Escherichia coli (E. coli) was identified viathe utilization of L-ascorbate (Ula) operon [3]. Numerous scientists are concerned with theinvestigation of UlaA, because they are key to many problems in functional biochemistry andclinical research. In recent years, such efforts have been made to understand the structure andstabilities of phosphohistidine and its interactions with L-ascorbic acid by experimentalworks [4]. Phosphohistidine plays an important role as an intermediate in the formation ofphosphoaspartic acid in E. coli [5]. The histidine containing phosphor carrier protein transfersa phosphate group between E. coli and L-ascorbic acid [4,5].In this work, the interaction of L-ascorbic acid and UlaA from E. coli was examined using abinito calculations.