Isolation and characterisation of a wheat phosphoenolpyruvate carboxylase gene.: Modelling of the encoded protein

A phosphoenolpyruvate carboxylase gene (referred to as Ppc1) was isolated from a wheat genomic library and sequenced in both strands. The deduced protein sequence is encoded by 10 exons and shows extensive similarities to that of other plant PEPCs sequenced so far, with respect to the predicted motives involved in the structure (beta-strands and alpha-helices) and function (active site, inhibitor site, N- and C-terminus) of the enzyme. Modelling of the 3D-structure of the wheat PEPC monomer using the Swiss-Model programme and the Escherichia coli PEPC monomer 3D-structure as a reference revealed that these motives and corresponding key residues share very similar positions in the folded plant and bacterial polypeptides. Interestingly, the 5'-flanking sequence of Ppc1 gene contains various putative regulatory cis-elements including an ABRE box. Relative RT-PCR analysis showed a ubiquitous expression of Ppc1 gene in developing and germinating wheat seeds as well as in developing seedlings. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.