1
|
González Álvarez Á, Martinez I Quer A, Ellegaard-Jensen L, Sapkota R, Carvalho PN, Johansen A. Fungal removal of cyanotoxins in constructed wetlands: The forgotten degraders. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 929:172590. [PMID: 38642746 DOI: 10.1016/j.scitotenv.2024.172590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/14/2024] [Accepted: 04/17/2024] [Indexed: 04/22/2024]
Abstract
Harmful cyanobacterial blooms have increased globally, releasing hazardous cyanotoxins that threaten the safety of water resources. Constructed wetlands (CWs) are a nature-based and low-cost solution to purify and remove cyanotoxins from water. However, bio-mechanistic understanding of the biotransformation processes expected to drive cyanotoxin removal in such systems is poor, and primarily focused on bacteria. Thus, the present study aimed at exploring the fungal contribution to microcystin-LR and cylindrospermopsin biodegradation in CWs. Based on CW mesocosms, two experimental approaches were taken: a) amplicon sequencing studies were conducted to investigate the involvement of the fungal community; and b) CW fungal isolates were tested for their microcystin-LR and cylindrospermopsin degradation capabilities. The data uncovered effects of seasonality (spring or summer), cyanotoxin exposure, vegetation (unplanted, Juncus effusus or Phragmites australis) and substratum (sand or gravel) on the fungal community structure. Additionally, the arbuscular mycorrhizal fungus Rhizophagus and the endophyte Myrmecridium showed positive correlations with cyanotoxin removal. Fungal isolates revealed microcystin-LR-removal potentials of approximately 25 % in in vitro biodegradation experiments, while the extracellular chemical fingerprint of the cultures suggested a potential intracellular metabolization. The results from this study may help us understand the fungal contribution to cyanotoxin removal, as well as their ecology in CWs.
Collapse
Affiliation(s)
- Ángela González Álvarez
- Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark
| | - Alba Martinez I Quer
- Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark
| | - Lea Ellegaard-Jensen
- Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark; WATEC, Centre for Water Technology, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
| | - Rumakanta Sapkota
- Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark
| | - Pedro N Carvalho
- Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark; WATEC, Centre for Water Technology, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark.
| | - Anders Johansen
- Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark; WATEC, Centre for Water Technology, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
| |
Collapse
|
2
|
Yang J, Liang K, Ke H, Zhang Y, Meng Q, Gao L, Fan J, Li G, Zhou H, Xiao J, Lei X. Enzymatic Degradation of Deoxynivalenol with the Engineered Detoxification Enzyme Fhb7. JACS AU 2024; 4:619-634. [PMID: 38425922 PMCID: PMC10900206 DOI: 10.1021/jacsau.3c00696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/19/2024] [Accepted: 01/23/2024] [Indexed: 03/02/2024]
Abstract
In the era of global climate change, the increasingly severe Fusarium head blight (FHB) and deoxynivalenol (DON) contamination have caused economic losses and brought food and feed safety concerns. Recently, an FHB resistance gene Fhb7 coding a glutathione-S transferase (GST) to degrade DON by opening the critical toxic epoxide moiety was identified and opened a new window for wheat breeding and DON detoxification. However, the poor stability of Fhb7 and the elusiveness of the catalytic mechanism hinder its practical application. Herein, we report the first structure of Fhb7 at 2.41 Å and reveal a unique catalytic mechanism of epoxide opening transformation in GST family proteins. Furthermore, variants V29P and M10 showed that 5.5-fold and 266.7-fold longer half-life time than wild-type, respectively, were identified. These variants offer broad substrate scope, and the engineered biosafe Bacillus subtilis overexpressing the variants shows excellent DON degradation performance, exhibiting potential at bacterium engineering to achieve DON detoxification in the feed and biomedicine industry. This work provides a profound mechanistic insight into the enzymatic activities of Fhb7 and paves the way for further utilizing Fhb7-related enzymes in crop breeding and DON detoxification by synthetic biology.
Collapse
Affiliation(s)
- Jun Yang
- Beijing
National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic
Chemistry and Molecular Engineering of Ministry of Education, Department
of Chemical Biology, College of Chemistry and Molecular Engineering,
and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
- Academy
for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Kai Liang
- School
of Life Sciences, Peking University, Beijing 100871, China
| | - Han Ke
- Beijing
National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic
Chemistry and Molecular Engineering of Ministry of Education, Department
of Chemical Biology, College of Chemistry and Molecular Engineering,
and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Yuebin Zhang
- Laboratory
of Molecular Modeling and Design, State Key Laboratory of Molecular
Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Qian Meng
- Analytical
Research Center for Organic and Biological Molecules, State Key Laboratory
of Drug Research, Shanghai Institute of
Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Lei Gao
- Beijing
National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic
Chemistry and Molecular Engineering of Ministry of Education, Department
of Chemical Biology, College of Chemistry and Molecular Engineering,
and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Junping Fan
- Beijing
National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic
Chemistry and Molecular Engineering of Ministry of Education, Department
of Chemical Biology, College of Chemistry and Molecular Engineering,
and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Guohui Li
- Laboratory
of Molecular Modeling and Design, State Key Laboratory of Molecular
Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Hu Zhou
- Analytical
Research Center for Organic and Biological Molecules, State Key Laboratory
of Drug Research, Shanghai Institute of
Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
- University
of Chinese Academy of Sciences, Number 19A Yuquan Road, Beijing 100049, China
| | - Junyu Xiao
- School
of Life Sciences, Peking University, Beijing 100871, China
- Academy
for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Xiaoguang Lei
- Beijing
National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic
Chemistry and Molecular Engineering of Ministry of Education, Department
of Chemical Biology, College of Chemistry and Molecular Engineering,
and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
- Academy
for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- Institute
for Cancer Research, Shenzhen Bay Laboratory, Shenzhen 518107, China
| |
Collapse
|
3
|
Diversity of Omega Glutathione Transferases in mushroom-forming fungi revealed by phylogenetic, transcriptomic, biochemical and structural approaches. Fungal Genet Biol 2021; 148:103506. [PMID: 33450403 DOI: 10.1016/j.fgb.2020.103506] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 12/20/2020] [Accepted: 12/22/2020] [Indexed: 01/20/2023]
Abstract
The Omega class of glutathione transferases (GSTs) forms a distinct class within the cytosolic GST superfamily because most of them possess a catalytic cysteine residue. The human GST Omega 1 isoform was first characterized twenty years ago, but it took years of work to clarify the roles of the human isoforms. Concerning the kingdom of fungi, little is known about the cellular functions of Omega glutathione transferases (GSTOs), although they are widely represented in some of these organisms. In this study, we re-assess the phylogeny and the classification of GSTOs based on 240 genomes of mushroom-forming fungi (Agaricomycetes). We observe that the number of GSTOs is not only extended in the order of Polyporales but also in other orders such as Boletales. Our analysis leads to a new classification in which the fungal GSTOs are divided into two Types A and B. The catalytic residue of Type-A is either cysteine or serine, while that of Type-B is cysteine. The present study focuses on Trametes versicolor GSTO isoforms that possess a catalytic cysteine residue. Transcriptomic data show that Type-A GSTOs are constitutive enzymes while Type-B are inducible ones. The crystallographic analysis reveals substantial structural differences between the two types while they have similar biochemical profiles in the tested conditions. Additionally, these enzymes have the ability to bind antioxidant molecules such as wood polyphenols in two possible binding sites as observed from X-ray structures. The multiplication of GSTOs could allow fungal organisms to adapt more easily to new environments.
Collapse
|
4
|
Osman WHW, Mikami B, Saka N, Kondo K, Lin MI, Nagata T, Katahira M. Identification of key residues for activities of atypical glutathione S-transferase of Ceriporiopsis subvermispora, a selective degrader of lignin in woody biomass, by crystallography and functional mutagenesis. Int J Biol Macromol 2019; 132:222-229. [PMID: 30928378 DOI: 10.1016/j.ijbiomac.2019.03.199] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 03/26/2019] [Indexed: 01/05/2023]
Abstract
Ceriporiopsis subvermispora (C. subvermispora) is a selective degrader of lignin in the woody biomass. Glutathione S-transferases (GSTs) are multifunctional enzymes that play important roles in cellular detoxification and metabolism. The crystal structures of a GST of C. subvermispora, CsGST83044, in GSH-free and -bound forms were solved at 1.95 and 2.19 Å resolution, respectively. The structure of the GSH-bound form revealed that CsGST83044 can be categorized as an atypical-type of GST. In the GSH-bound form of CsGST83044, Asn22, Asn24, and Tyr46 are located closest to the sulfur atom and form hydrogen bonds with the thiol group. The functional mutagenesis indicated that they are critical for the enzymatic activities of CsGST83044. The critical residues of an atypical-type GST belonging to the GSTFuA class were revealed for the first time. A previous study indicated that CsGST83044 and another GST, CsGST63524, differ in substrate preference; CsGST83044 prefers smaller substrates than CsGST63524 for its esterase activity. The GSH-bound pocket of CsGST83044 turns out to be small, which may explain the preference for smaller substrates. Protein engineering of GSTs of C. subvermispora in the light of the obtained insight may pave a path in the future for utilization of the woody biomass.
Collapse
Affiliation(s)
- Wan Hasnidah Wan Osman
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan; Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Bunzo Mikami
- Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Naoki Saka
- Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Keiko Kondo
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Meng-I Lin
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan; Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Takashi Nagata
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan; Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.
| | - Masato Katahira
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan; Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.
| |
Collapse
|
5
|
Wan Osman WH, Mikami B, Saka N, Kondo K, Nagata T, Katahira M. Structure of a serine-type glutathione S-transferase of Ceriporiopsis subvermispora and identification of the enzymatically important non-canonical residues by functional mutagenesis. Biochem Biophys Res Commun 2019; 510:177-183. [PMID: 30683313 DOI: 10.1016/j.bbrc.2019.01.076] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 01/16/2019] [Indexed: 11/30/2022]
Abstract
Ceriporiopsis subvermispora (C. subvermispora), one of the white-rot fungi, is known as a selective lignin degrader of the woody biomass. Glutathione S-transferases (GSTs) are multifunctional enzymes that are capable of catalyzing the reactions involved in detoxification and metabolic pathways. In this study, a GST of C. subvermispora, named CsGST63524, was overexpressed in E. coli, and then purified by affinity, anion exchange, and size exclusion column chromatography. The crystal structures of the CsGST63524 in ligand-free and complex with GSH were refined at 2.45 and 2.50 Å resolutions, respectively. The sulfur atom of glutathione forms a hydrogen bond with Ser21 of CsGST63524, indicating it is a serine-type GST. Mutagenesis of Ser21 unexpectedly indicated that this serine residue is not essential for the enzymatic activity of CsGST63524. Comparative sequence and structural analyses, together with functional mutagenesis, newly identified the enzymatically important non-canonical amino acid residues, Asn23 and Tyr45, other than the serine residue.
Collapse
Affiliation(s)
- Wan Hasnidah Wan Osman
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan; Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Bunzo Mikami
- Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Naoki Saka
- Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Keiko Kondo
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Takashi Nagata
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan; Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan.
| | - Masato Katahira
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan; Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan.
| |
Collapse
|