A cDNA library was constructed from poly(A) + RNA from suspension-cultured cells of Lupinus polyphyllus [ 1 ], which derived from stem tissue [2] and transferred to fresh medium weekly [3]. The cDNA synthesis was carded out using a RNase H approach and Eco RI adaptor strategy [ 1 ]. The cDNA-adaptor construction was cloned in the Eco RI sites of the expression vector pUC 19 and the cDNA library was established by transforming competent Escherichia coli DH5~ according to the method of the manufacturer to get 2.5 x 105 transformants/pg poly(A) + RNA. The library was screened immunologically with polyclonal antibodies against horse radish peroxidase. 17 positive clones with inserts between 500 and 1500 basepairs were isolated and sequenced by the chain termination and/or chemical method. The clone pPLZ12 consists of 790 bp with an open reading frame starting at position 115 and terminating at position 666 (Fig. 1). The deduced polypeptide contains 184 amino acids with a calculated molecular weight of 20 566. A search in the protein and gene databases (EMBL, GenBank, NBRF, Swissprot) did not reveal significant homologies to peroxidases or other known sequences. RNA was isolated from plants and suspension-cultured cells of L. polyphyllus and hybridized with pPLZ 12. We observed a high