Abstract:

Prunasin hydrolase (PH) gene was cloned from sweet and bitter apricot (Prunus armeniaca L.) kernels from
the cultivars Luntai Xiaobaixing and Jiamaihuangxing, respectively. The PH gene from Luntai Xiaobaixing was named as
PaLTPh (GenBank accession number: KF888615) with a sequence length of 3 686 bp, and that from Jiamaihuangxing was
named as PaMJPh (GenBank accession number: KF888616) with a sequence length of 3 690 bp. Analysis of the nucleotide
sequences indicated that the homology between the PH gene and the PH691 gene of Prunus dulcis reached up to 94%.
Moreover, the coding sequence (CDS) region was cloned according to the conserved regions of PaLTPh and PaMJPh. The
sequence length of both PaLTPh CDS (KF888617) and PaMJPh CDS (KF888618) was 1 635 bp. Both these CDS regions
were full open reading frame (ORF) sequences, encoding a protein consisting of 544 amino acid (aa) residues. Both proteins
contained an amino-terminal signal peptide with 26 AA residues and the domain of glycosyl hydrolase family Ⅰ for PaLTPH
and PaMJPH, which can catalyze the hydrolysis of prunasin to mandelonitrile and glycosides. This study has demonstrated
that the PH gene from apricot has high homology with the Ph691 of Prunus dulcis.

Key words: Prunus armeniaca L. cultivar Luntai Xiaobaixing, Prunus armeniaca L. cultivar Jiamaihuangxing, prunasin, prunasin hydrolase, gene cloning