A full-length cDNA encoding phosphoenolpyruvate carboxylase (PEPC) was isolated from tropical epiphytic CAM orchid Mokara Yellow. The cDNA designated as Mpepc1 is 3 450 bp in length with an open reading frame of 2 862 bp encoding 954 amino acids. The deduced amino acid sequence of Mpepc1 shows 83 % identity with pepc2 of sorghum, 82 % with pepc1 and pepc2 of maize and 81 % with pepc of Arabidopsis thaliana. RT-PCR analysis showed that Mpepc1 was expressed in mature leaves, immature leaves, and aerial roots of M. Yellow. No expression was detected in the flower.