Purification and Molecular Analysis of an Extracellular γ-Glutamyl Hydrolase Present in Young Tissues of the Soybean Plant

• Published in: Biochemical and biophysical research communications Vol. 228; no. 1; pp. 1 - 6
• Main Authors: Huangpu, J., Pak, J.H., Graham, M.C., Rickle, S.A., Graham, J.S.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.11.1996
• Subjects: Blotting, Western; Cell Wall - enzymology; Cross Reactions; DNA, Complementary - genetics; FEUILLE; gamma-Glutamyl Hydrolase - chemistry; gamma-Glutamyl Hydrolase - genetics; gamma-Glutamyl Hydrolase - isolation & purification; gamma-Glutamyl Hydrolase - metabolism; Gene Expression; GENETICA MOLECULAR; GENETIQUE MOLECULAIRE; GLYCINE MAX; Glycine max - enzymology; HIDROLASAS; HOJAS; HYDROLASE; Metalloendopeptidases - immunology; Molecular Sequence Data; PARED CELULAR; PAROI CELLULAIRE; PEPTIDASAS; PEPTIDASE; PEPTIDE; PEPTIDOS; Plant Leaves - enzymology; PURIFICACION; PURIFICATION; RACINE; RAICES; RNA, Messenger - genetics; RNA, Messenger - metabolism; RNA, Plant - genetics; RNA, Plant - metabolism; TALLO; TIGE
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1006/bbrc.1996.1608

A polypeptide present in intercellular wash fluids of young leaves ofGlycine maxhas been purified to electrophoretic homogeneity. The protein has been identified as γ-glutamyl hydrolase (GGH) based on the shared homology with a recently cloned cDNA from rat. The enzyme is present within the extracellular space of young leaves and a portion is bound to the cell wall. Northern and Western analysis confirm that this polypeptide is expressed only in young (1-15 d old) leaf, stem and root tissue and is therefore expressed under a strict developmental program. The primary sequence of γ-glutamyl hydrolase shares amino acid identity with a cDNA clone from rat and two partially sequenced cDNAs fromArabidopsis.Although the completein vivofunction of γ-glutamyl hydrolase in plants is unclear, it is known that the protein plays a critical role in folate metabolism and therefore likely in meeting the physiological demands of growing plant tissues.