Dechlorination of polychlorobiphenyl degradation metabolites by a recombinant glutathione S-transferase from Acidovorax sp. KKS102

A glutathione S-transferase (GST) with a potential dehalogenation function against various organochlorine substrates was identified from a polychlorobiphenyl (PCB)-degrading organism, Acidovorax sp. KKS102. A homolog of the gene BphK (biphenyl upper pathway K), named BphK-KKS, was cloned, purified a...

Full description

Bibliographic Details
Main Authors: Shehu, Dayyabu, Alias, Zazali
Format: Article
Published: Wiley Open Access 2019
Subjects:
_version_ 1825722064437248000
author Shehu, Dayyabu
Alias, Zazali
author_facet Shehu, Dayyabu
Alias, Zazali
author_sort Shehu, Dayyabu
collection UM
description A glutathione S-transferase (GST) with a potential dehalogenation function against various organochlorine substrates was identified from a polychlorobiphenyl (PCB)-degrading organism, Acidovorax sp. KKS102. A homolog of the gene BphK (biphenyl upper pathway K), named BphK-KKS, was cloned, purified and biochemically characterized. Bioinformatic analysis indicated several conserved amino acids that participated in the catalytic activity of the enzyme, and site-directed mutagenesis of these conserved amino acids revealed their importance in the enzyme's catalytic activity. The wild-type and mutant (C10F, K107T and A180P) recombinant proteins displayed wider substrate specificity. The wild-type recombinant GST reacted towards 1-chloro-2,4-dinitrobenzene (CDNB), ethacrynic acid, hydrogen peroxide and cumene hydroperoxide. The mutated recombinant proteins, however, showed significant variation in specific activities towards the substrates. A combination of a molecular docking study and a chloride ion detection assay showed potential interaction with and a dechlorination function against 2-, 3- and 4-chlorobenzoates (metabolites generated during PCB biodegradation) in addition to some organochlorine pesticides (dichlorodiphenyltrichloroethane, endosulfan and permethrin). It was demonstrated that the behavior of the dechlorinating activities varied among the wild-type and mutant recombinant proteins. Kinetic studies (using CDNB and glutathione) showed that the kinetic parameters K m , V max , K cat and K m /K cat were all affected by the mutations. While C10F and A180P mutants displayed an increase in GST activity and the dechlorination function of the enzyme, the K107T mutant displayed variable results, suggesting a functional role of Lys107 in determining substrate specificity of the enzyme. These results demonstrated that the enzyme should be valuable in the bioremediation of metabolites generated during PCB biodegradation. © 2018 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.
first_indexed 2024-03-06T05:59:56Z
format Article
id um.eprints-23465
institution Universiti Malaya
last_indexed 2024-03-06T05:59:56Z
publishDate 2019
publisher Wiley Open Access
record_format dspace
spelling um.eprints-234652020-01-16T07:07:26Z http://eprints.um.edu.my/23465/ Dechlorination of polychlorobiphenyl degradation metabolites by a recombinant glutathione S-transferase from Acidovorax sp. KKS102 Shehu, Dayyabu Alias, Zazali Q Science (General) QH Natural history QR Microbiology A glutathione S-transferase (GST) with a potential dehalogenation function against various organochlorine substrates was identified from a polychlorobiphenyl (PCB)-degrading organism, Acidovorax sp. KKS102. A homolog of the gene BphK (biphenyl upper pathway K), named BphK-KKS, was cloned, purified and biochemically characterized. Bioinformatic analysis indicated several conserved amino acids that participated in the catalytic activity of the enzyme, and site-directed mutagenesis of these conserved amino acids revealed their importance in the enzyme's catalytic activity. The wild-type and mutant (C10F, K107T and A180P) recombinant proteins displayed wider substrate specificity. The wild-type recombinant GST reacted towards 1-chloro-2,4-dinitrobenzene (CDNB), ethacrynic acid, hydrogen peroxide and cumene hydroperoxide. The mutated recombinant proteins, however, showed significant variation in specific activities towards the substrates. A combination of a molecular docking study and a chloride ion detection assay showed potential interaction with and a dechlorination function against 2-, 3- and 4-chlorobenzoates (metabolites generated during PCB biodegradation) in addition to some organochlorine pesticides (dichlorodiphenyltrichloroethane, endosulfan and permethrin). It was demonstrated that the behavior of the dechlorinating activities varied among the wild-type and mutant recombinant proteins. Kinetic studies (using CDNB and glutathione) showed that the kinetic parameters K m , V max , K cat and K m /K cat were all affected by the mutations. While C10F and A180P mutants displayed an increase in GST activity and the dechlorination function of the enzyme, the K107T mutant displayed variable results, suggesting a functional role of Lys107 in determining substrate specificity of the enzyme. These results demonstrated that the enzyme should be valuable in the bioremediation of metabolites generated during PCB biodegradation. © 2018 The Authors. Published by FEBS Press and John Wiley & Sons Ltd. Wiley Open Access 2019 Article PeerReviewed Shehu, Dayyabu and Alias, Zazali (2019) Dechlorination of polychlorobiphenyl degradation metabolites by a recombinant glutathione S-transferase from Acidovorax sp. KKS102. FEBS Open Bio, 9 (3). pp. 408-419. ISSN 2211-5463, DOI https://doi.org/10.1002/2211-5463.12405 <https://doi.org/10.1002/2211-5463.12405>. https://doi.org/10.1002/2211-5463.12405 doi:10.1002/2211-5463.12405
spellingShingle Q Science (General)
QH Natural history
QR Microbiology
Shehu, Dayyabu
Alias, Zazali
Dechlorination of polychlorobiphenyl degradation metabolites by a recombinant glutathione S-transferase from Acidovorax sp. KKS102
title Dechlorination of polychlorobiphenyl degradation metabolites by a recombinant glutathione S-transferase from Acidovorax sp. KKS102
title_full Dechlorination of polychlorobiphenyl degradation metabolites by a recombinant glutathione S-transferase from Acidovorax sp. KKS102
title_fullStr Dechlorination of polychlorobiphenyl degradation metabolites by a recombinant glutathione S-transferase from Acidovorax sp. KKS102
title_full_unstemmed Dechlorination of polychlorobiphenyl degradation metabolites by a recombinant glutathione S-transferase from Acidovorax sp. KKS102
title_short Dechlorination of polychlorobiphenyl degradation metabolites by a recombinant glutathione S-transferase from Acidovorax sp. KKS102
title_sort dechlorination of polychlorobiphenyl degradation metabolites by a recombinant glutathione s transferase from acidovorax sp kks102
topic Q Science (General)
QH Natural history
QR Microbiology
work_keys_str_mv AT shehudayyabu dechlorinationofpolychlorobiphenyldegradationmetabolitesbyarecombinantglutathionestransferasefromacidovoraxspkks102
AT aliaszazali dechlorinationofpolychlorobiphenyldegradationmetabolitesbyarecombinantglutathionestransferasefromacidovoraxspkks102