title: Presence of unique glyoxalase III proteins in plants indicates the existence of shorter route for methylglyoxal detoxification.
abstract: Glyoxalase pathway, comprising glyoxalase I (GLY I) and glyoxalase II (GLY II) enzymes, is the major pathway for detoxification of methylglyoxal (MG) into D-lactate involving reduced glutathione (GSH). However, in bacteria, glyoxalase III (GLY III) with DJ-1/PfpI domain(s) can do the same conversion in a single step without GSH. Our investigations for the presence of DJ-1/PfpI domain containing proteins in plants have indicated the existence of GLY III-like proteins in monocots, dicots, lycopods, gymnosperm and bryophytes. A deeper in silico analysis of rice genome identified twelve DJ-1 proteins encoded by six genes. Detailed analysis has been carried out including their chromosomal distribution, genomic architecture and localization. Transcript profiling under multiple stress conditions indicated strong induction of OsDJ-1 in response to exogenous MG. A member of OsDJ-1 family, OsDJ-1C, showed high constitutive expression at all developmental stages and tissues of rice. MG depletion study complemented by simultaneous formation of D-lactate proved OsDJ-1C to be a GLY III enzyme that converts MG directly into D-lactate in a GSH-independent manner. Site directed mutagenesis of Cys-119 to Alanine significantly reduces its GLY III activity indicating towards the existence of functional GLY III enzyme in rice-a shorter route for MG detoxification.
authors.affiliation: Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi-110067, India.|Present address: Department of Biochemistry and Molecular Biology, Shahjalal University of Science and Technology, Sylhet-3114, Bangladesh.
authors.forename: Ajit
authors.initials: A
authors.lastname: Ghosh
authors.affiliation: Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi-110067, India.
authors.forename: Hemant R
authors.initials: HR
authors.lastname: Kushwaha
authors.affiliation: Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi-110067, India.
authors.forename: Mohammad R
authors.initials: MR
authors.lastname: Hasan
authors.affiliation: Stress Physiology and Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi-110067, India.
authors.forename: Ashwani
authors.initials: A
authors.lastname: Pareek
authors.affiliation: Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi-110067, India.
authors.forename: Sudhir K
authors.initials: SK
authors.lastname: Sopory
authors.affiliation: Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi-110067, India.
authors.forename: Sneh L
authors.initials: SL
authors.lastname: Singla-Pareek
mesh_terms: D000445:Aldehyde Oxidoreductases / Q000737:chemistry / Q000378:metabolism*; D000595:Amino Acid Sequence; D020134:Catalytic Domain; D002874:Chromosome Mapping; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D018745:Genome, Plant; D008658:Inactivation, Metabolic; D053858:Metabolic Networks and Pathways; D009154:Mutation; D009928:Organ Specificity / Q000235:genetics; D012275:Oryza / Q000145:classification / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism; D010944:Plants / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D054730:Protein Interaction Domains and Motifs; D011765:Pyruvaldehyde / Q000378:metabolism*; D020218:Response Elements; D013312:Stress, Physiological
chemical_list: D010940:Plant Proteins; D011765:Pyruvaldehyde; D000445:Aldehyde Oxidoreductases; C091855:glyoxalase III