Molecular identification and functional delineation of a glutathione reductase homolog from disk abalone (Haliotis discus discus): Insights as a potent player in host antioxidant defense.

Autor: Herath HMLPB; Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea., Wickramasinghe PDSU; Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea., Bathige SDNK; Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea., Jayasooriya RGPT; Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea., Kim GY; Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea., Park MA; Southeast Sea Fisheries Research Institute, National Institutie of Fisheries Science, Tongyeong-si, Gyoengsangnam-do, 53085, Republic of Korea., Kim C; Informatics Development & Management Group, Korea Institute of Oriental Medicine, 1672 Yuseongdae-ro, Yuseong-gu, Daejeon, 34054, Republic of Korea. Electronic address: chulnice@kiom.re.kr., Lee J; Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province, 63243, Republic of Korea. Electronic address: jehee@jejunu.ac.kr.
Jazyk: angličtina
Zdroj: Fish & shellfish immunology [Fish Shellfish Immunol] 2017 Jan; Vol. 60, pp. 355-367. Date of Electronic Publication: 2016 Dec 03.
DOI: 10.1016/j.fsi.2016.12.002
Abstrakt: Glutathione reductase (GSR) is an enzyme that catalyzes the biochemical conversion of oxidized glutathione (GSSG) into the reduced form (GSH). Since the ratio between the two forms of glutathione (GSH/GSSG) is important for the optimal function of GSH to act as an antioxidant against H 2 O 2 , the contribution of GSR as an enzymatic regulatory agent to maintain the proper ratio is essential. Abalones are marine mollusks that frequently encounter environmental factors that can trigger the overproduction of reactive oxygen species (ROS) such as H 2 O 2 . Therefore, we conducted the current study to reveal the molecular and functional properties of a GSR homolog in the disk abalone, Haliotis discus discus. The identified cDNA sequence (2325 bp) has a 1356 bp long open reading frame (ORF), coding for a 909 bp long amino acid sequence, which harbors a pyridine nucleotide-disulfide oxidoreductase domain (171-246 aa), a pyridine nucleotide-disulfide oxidoreductase dimerization domain, and a NAD(P)(+)-binding Rossmann fold superfamily signature domain. Four functional residues: the FAD binding site, glutathione binding site, NADPH binding motif, and assembly domain were identified to be conserved among the other species. The recombinant abalone GSR (rAbGSR) exhibited detectable activity in a standard glutathione reductase activity assay. The optimum pH and optimal temperature for the reaction were found to be 7.0 and 50 °C, respectively, while the ionic strength of the medium had no effect. The enzymatic reaction was vastly inhibited by Cu +2 and Cd +2 ions. A considerable effect of cellular protection was detected with a disk diffusion assay conducted with rAbGSR. Moreover, an MTT assay and flow cytometry confirmed the significance of the protective role of rAbGSR in cell function. Furthermore, AbGSR was found to be ubiquitously distributed in different types of abalone tissues. AbGSR mRNA expression was significantly upregulated in response to three immune challenges: Vibrio parahaemolyticus, Listeria monocytogenes, and lipopolysaccharide (LPS), thus indicating its possible involvement in host defense mechanisms during pathogenic infections. Taken together, the results of the current study suggest that AbGSR plays an important role in antioxidant-mediated host defense mechanisms and also provide insights into the immunological contribution of AbGSR.
(Copyright © 2016 Elsevier Ltd. All rights reserved.)
Databáze: MEDLINE
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