Cry Protein Crystal-Immobilized Metallothioneins for Bioremediation of Heavy Metals from Water
Cry proteins have been the subject of intense research due to their ability to form crystals naturally in <i>Bacillus thuringiensis (Bt)</i>. In this research we developed a new strategy that allows for the removal of cadmium and chromium from wastewater by using one Cry protein, Cry3Aa,...
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| Format: | Article |
| Language: | English |
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MDPI AG
2019-06-01
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| Series: | Crystals |
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| Online Access: | https://www.mdpi.com/2073-4352/9/6/287 |
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| author | Qian Sun Sze Wan Cheng Kelton Cheung Marianne M. Lee Michael K. Chan |
| author_facet | Qian Sun Sze Wan Cheng Kelton Cheung Marianne M. Lee Michael K. Chan |
| author_sort | Qian Sun |
| collection | DOAJ |
| description | Cry proteins have been the subject of intense research due to their ability to form crystals naturally in <i>Bacillus thuringiensis (Bt)</i>. In this research we developed a new strategy that allows for the removal of cadmium and chromium from wastewater by using one Cry protein, Cry3Aa, as a framework to immobilize tandem repeats of the cyanobacterial metallothionein SmtA from <i>Synechococcus elongatus</i> (strain PCC 7942). SmtA is a low molecular weight cysteine-rich protein known to bind heavy metals. A series of Cry3Aa-SmtA constructs were produced by the fusion of one, three, or six tandem repeats of SmtA to Cry3Aa. Overexpression of these constructs in <i>Bt</i> resulted in the production of pure Cry3Aa-SmtA fusion crystals that exhibited similar size, crystallinity, and morphology to that of native Cry3Aa protein crystals. All three Cry3Aa-SmtA constructs exhibited efficient binding to cadmium and chromium, with the binding capacity correlated with increasing SmtA copy number. These results suggest the potential use of Cry3Aa-SmtA crystals as a novel biodegradable and cost-effective approach to the removal of toxic heavy metals from the environment. |
| first_indexed | 2024-04-11T12:38:57Z |
| format | Article |
| id | doaj.art-75938d12502e4857b51bf7b45caf8cd5 |
| institution | Directory Open Access Journal |
| issn | 2073-4352 |
| language | English |
| last_indexed | 2024-04-11T12:38:57Z |
| publishDate | 2019-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Crystals |
| spelling | doaj.art-75938d12502e4857b51bf7b45caf8cd52022-12-22T04:23:33ZengMDPI AGCrystals2073-43522019-06-019628710.3390/cryst9060287cryst9060287Cry Protein Crystal-Immobilized Metallothioneins for Bioremediation of Heavy Metals from WaterQian Sun0Sze Wan Cheng1Kelton Cheung2Marianne M. Lee3Michael K. Chan4School of Life Sciences and Center of Novel Biomaterials, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, ChinaSchool of Life Sciences and Center of Novel Biomaterials, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, ChinaSchool of Life Sciences and Center of Novel Biomaterials, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, ChinaSchool of Life Sciences and Center of Novel Biomaterials, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, ChinaSchool of Life Sciences and Center of Novel Biomaterials, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, ChinaCry proteins have been the subject of intense research due to their ability to form crystals naturally in <i>Bacillus thuringiensis (Bt)</i>. In this research we developed a new strategy that allows for the removal of cadmium and chromium from wastewater by using one Cry protein, Cry3Aa, as a framework to immobilize tandem repeats of the cyanobacterial metallothionein SmtA from <i>Synechococcus elongatus</i> (strain PCC 7942). SmtA is a low molecular weight cysteine-rich protein known to bind heavy metals. A series of Cry3Aa-SmtA constructs were produced by the fusion of one, three, or six tandem repeats of SmtA to Cry3Aa. Overexpression of these constructs in <i>Bt</i> resulted in the production of pure Cry3Aa-SmtA fusion crystals that exhibited similar size, crystallinity, and morphology to that of native Cry3Aa protein crystals. All three Cry3Aa-SmtA constructs exhibited efficient binding to cadmium and chromium, with the binding capacity correlated with increasing SmtA copy number. These results suggest the potential use of Cry3Aa-SmtA crystals as a novel biodegradable and cost-effective approach to the removal of toxic heavy metals from the environment.https://www.mdpi.com/2073-4352/9/6/287Cry protein crystalsmetallothioneinsbioremediationheavy metal contamination |
| spellingShingle | Qian Sun Sze Wan Cheng Kelton Cheung Marianne M. Lee Michael K. Chan Cry Protein Crystal-Immobilized Metallothioneins for Bioremediation of Heavy Metals from Water Crystals Cry protein crystals metallothioneins bioremediation heavy metal contamination |
| title | Cry Protein Crystal-Immobilized Metallothioneins for Bioremediation of Heavy Metals from Water |
| title_full | Cry Protein Crystal-Immobilized Metallothioneins for Bioremediation of Heavy Metals from Water |
| title_fullStr | Cry Protein Crystal-Immobilized Metallothioneins for Bioremediation of Heavy Metals from Water |
| title_full_unstemmed | Cry Protein Crystal-Immobilized Metallothioneins for Bioremediation of Heavy Metals from Water |
| title_short | Cry Protein Crystal-Immobilized Metallothioneins for Bioremediation of Heavy Metals from Water |
| title_sort | cry protein crystal immobilized metallothioneins for bioremediation of heavy metals from water |
| topic | Cry protein crystals metallothioneins bioremediation heavy metal contamination |
| url | https://www.mdpi.com/2073-4352/9/6/287 |
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