title: The Arabidopsis KS-type dehydrin recovers lactate dehydrogenase activity inhibited by copper with the contribution of His residues.
abstract: Dehydrin, which is one of the late embryogenesis abundant (LEA) proteins, is involved in the ability of plants to tolerate the lack of water. Although many reports have indicated that dehydrins bind heavy metals, the physiological role of this metal binding has not been well understood. Here, we report that the Arabidopsis KS-type dehydrin (AtHIRD11) recovered the lactate dehydrogenase (LDH) activity denatured by Cu(2+). The LDH activity was partially inhibited by 0.93 μM Cu(2+) but totally inactivated by 9.3 μM Cu(2+). AtHIRD11 recovered the activity of LDH treated with 9.3 μM Cu(2+) in a dose-dependent manner. The recovery activity of AtHIRD11 was significantly higher than those of serum albumin and lysozyme. The conversion of His residues to Ala in AtHIRD11 resulted in the loss of the Cu(2+) binding of the protein as well as the disappearance of the conformational change induced by Cu(2+) that is observed by circular dichroism spectroscopy. The mutant protein showed lower recovery activity than the original AtHIRD11. These results indicate that AtHIRD11 can reactivate LDH inhibited by Cu(2+) via the His residues. This function may prevent physiological damage to plants due to heavy-metal stress.
authors.affiliation: Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan. Electronic address: hara.masakazu@shizuoka.ac.jp.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Hara
authors.affiliation: Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.
authors.forename: Shuhei
authors.initials: S
authors.lastname: Monna
authors.affiliation: Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.
authors.forename: Takae
authors.initials: T
authors.lastname: Murata
authors.affiliation: Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.
authors.forename: Taiyo
authors.initials: T
authors.lastname: Nakano
authors.affiliation: Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan.
authors.forename: Shono
authors.initials: S
authors.lastname: Amano
authors.affiliation: Institut für Pharmazeutische Chemie, Technische Universität Braunschweig, Beethovenstraße 55, 38106 Braunschweig, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Nachbar
authors.affiliation: Institut für Pharmazeutische Chemie, Technische Universität Braunschweig, Beethovenstraße 55, 38106 Braunschweig, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Wätzig
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017360:Arabidopsis / Q000187:drug effects / Q000378:metabolism*; D002417:Cattle; D003300:Copper / Q000633:toxicity*; D006639:Histidine / Q000378:metabolism*; D045022:Lactate Dehydrogenases / Q000378:metabolism*; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism*; D011487:Protein Conformation; D011817:Rabbits; D013329:Structure-Activity Relationship
chemical_list: D010940:Plant Proteins; C070556:dehydrin proteins, plant; D006639:Histidine; D003300:Copper; D045022:Lactate Dehydrogenases
keywords: Copper; Dehydrin; Heavy metal; His