Recombinant Entamoeba histolytica Pyruvate, phosphate dikinase (PPDK), partial

CUSABIO transfected the expression vector which inserted the recombinant DNA into the E.coli, cultured the cells, and then induced the transcription and translation of the cloned vector. The N-terminal 6xHis-SUMO tag sequence was appended to the gene coding for the E.coli of the Entamoeba histolytica PPDK protein to form the recombinant DNA. The recombinant Entamoeba histolytica PPDK was expressed as N-terminal 6xHis-SUMO-tagged fusion. The purity of the protein is greater than 90% assayed by SDS-PAGE. It has an apparent molecular weight of approximately 55 kDa.

PPDK is known for its role in C4 photosynthesis but has no established function in C3 plants. Cytosolic PPDK isoforms are generally expressed in non-photosynthetic organs of C3 and C4 plants. Some studies have shown that cyto-solic PPDK isinvolved in a metabolic response to water deficit and low-oxygen stress in rice,an anoxia-tolerant species. As a critical enzyme for C4 photosynthesis, PPDK provides the primary acceptor for fixation of bicarbonate in mesophyll cells. Although first isolated in C4 plants, it is also present in C3 species. Studies suggested that PPDK may be important in supplying PEP to gluconeogenesis, and in ageing leaves it allows remobilisation of nitrogen to supply reproductive tissue.