title: Identification of a new phospholipase D in Carica papaya latex.
abstract: Phospholipase D (PLD) is a lipolytic enzyme involved in signal transduction, vesicle trafficking and membrane metabolism. It catalyzes the hydrolysis and transphosphatidylation of glycerophospholipids at the terminal phosphodiester bond. The presence of a PLD in the latex of Carica papaya (CpPLD1) was demonstrated by transphosphatidylation of phosphatidylcholine (PtdCho) in the presence of 2% ethanol. Although the protein could not be purified to homogeneity due to its presence in high molecular mass aggregates, a protein band was separated by SDS-PAGE after SDS/chloroform-methanol/TCA-acetone extraction of the latex insoluble fraction. This material was digested with trypsin and the amino acid sequences of the tryptic peptides were determined by micro-LC/ESI/MS/MS. These sequences were used to identify a partial cDNA (723 bp) from expressed sequence tags (ESTs) of C. papaya. Based upon EST sequences, a full-length gene was identified in the genome of C. papaya, with an open reading frame of 2424 bp encoding a protein of 808 amino acid residues, with a theoretical molecular mass of 92.05 kDa. From sequence analysis, CpPLD1 was identified as a PLD belonging to the plant phosphatidylcholine phosphatidohydrolase family.
authors.affiliation: CNRS, Aix-Marseille Université, Enzymologie Interfaciale et Physiologie de la Lipolyse, Marseille, France. slim.abdelkafi@enis.rnu.tn
authors.forename: Slim
authors.initials: S
authors.lastname: Abdelkafi
authors.forename: Abdelkarim
authors.initials: A
authors.lastname: Abousalham
authors.forename: Imen
authors.initials: I
authors.lastname: Fendri
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ogata
authors.forename: Nathalie
authors.initials: N
authors.lastname: Barouh
authors.forename: Benjamin
authors.initials: B
authors.lastname: Fouquet
authors.forename: Frantz
authors.initials: F
authors.lastname: Scheirlinckx
authors.forename: Pierre
authors.initials: P
authors.lastname: Villeneuve
authors.forename: Frédéric
authors.initials: F
authors.lastname: Carrière
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D029441:Carica / Q000201:enzymology* / Q000378:metabolism; D007840:Latex / Q000378:metabolism; D008969:Molecular Sequence Data; D010739:Phospholipase D / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D010802:Phylogeny; D010944:Plants / Q000201:enzymology / Q000378:metabolism
chemical_list: D007840:Latex; D010739:Phospholipase D