Purification of glyoxalase I from onion bulbs and molecular cloning of its cDNA.
Biosci Biotechnol Biochem 2009;
73:2007-13. [PMID:
19734676 DOI:
10.1271/bbb.90194]
[Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Glyoxalase I was highly purified from onion bulbs by DEAE-cellulose, hydroxyapatite, and S-hexylglutathione-agarose column chromatography. With 356 micromol min(-1) mg(-1) protein, the specific enzymatic activity of the purified enzyme is the highest reported to date in plants. The purified enzyme showed a single major band with a relative molecular mass of approximately 25,000 on SDS-PAGE. A cDNA encoding glyoxalase I was cloned and sequenced. Sequence comparison suggested that it is to be classified as a short-type glyoxalase I. The expression pattern of glyoxalase I in healthy onion plants and responses to various stresses were examined by Western blotting. Glyoxalase I exists at high concentration in roots, young bulbs, mature bulbs, and mature leaves, the highest concentration being in mature bulbs. Up-regulation of glyoxalase I and glyoxalase II enzyme activities were observed in response to various stresses, and an increase in Gly I protein was also seen by immunoblotting. Our results suggest an important role of the glyoxalase I gene in the plant abiotic stress response.
Collapse