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Zhao W, Poncet-Legrand C, Staunton S, Quiquampoix H. pH-Dependent Changes in Structural Stabilities of Bt Cry1Ac Toxin and Contrasting Model Proteins following Adsorption on Montmorillonite. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:5693-5702. [PMID: 36989144 DOI: 10.1021/acs.est.2c09310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The environmental fate of insecticidal Cry proteins, including time-dependent conservation of biological properties, results from their structural stability in soils. The complex cascade of reactions involved in biological action requires Cry proteins to be in solution. However, the pH-dependent changes in conformational stability and the adsorption-desorption mechanisms of Cry protein on soil minerals remain unclear. We used Derjaguin-Landau-Verwey-Overbeek (DLVO) calculation and differential scanning calorimetry to interpret the driving forces and structural stabilities of Cry1Ac and two contrasting model proteins adsorbed by montmorillonite. The structural stability of Cry1Ac is closer to that of the "hard" protein, α-chymotrypsin, than that of the "soft" bovine serum albumin (BSA). The pH-dependent adsorption of Cry1Ac and α-chymotrypsin could be explained by DLVO theory, whereas the BSA adsorption deviated from it. Patch-controlled electrostatic attraction, hydrophobic effects, and entropy changes following protein unfolding on a mineral surface could contribute to Cry1Ac adsorption. Cry1Ac, like chymotrypsin, was partly denatured on montmorillonite, and its structural stability decreased with an increase in pH. Moreover, small changes in the conformational heterogeneity of both Cry1Ac and chymotrypsin were observed following adsorption. Conversely, adsorbed BSA was completely denatured regardless of the solution pH. The moderate conformational rearrangement of adsorbed Cry1Ac may partially explain why the insecticidal activity of Bt toxin appears to be conserved in soils, albeit for a relatively short time period.
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Affiliation(s)
- Wenqiang Zhao
- Eco&Sols, INRAE, IRD, Cirad, Institut Agro, Univ Montpellier, 34090 Montpellier, France
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
| | | | - Siobhan Staunton
- Eco&Sols, INRAE, IRD, Cirad, Institut Agro, Univ Montpellier, 34090 Montpellier, France
| | - Hervé Quiquampoix
- Eco&Sols, INRAE, IRD, Cirad, Institut Agro, Univ Montpellier, 34090 Montpellier, France
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Wang Y, Zhou X, Zhang F, Zhang L, Yang P, Maimaitiniyazi R. Effects of Pb(II) and Zn(II) Contamination on Adsorption, Desorption and Degradation of Cry1Ac Toxin Identical to Bt Transgenic Poplar in Black Soil. TOXICS 2023; 11:89. [PMID: 36850965 PMCID: PMC9959839 DOI: 10.3390/toxics11020089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 01/09/2023] [Accepted: 01/13/2023] [Indexed: 06/18/2023]
Abstract
Bt transgenic white poplar has been commercially planted in China since 2002, and it showed obvious insect resistance in the field. However, the ecological risk of planting Bt transgenic poplar in a field contaminated with heavy metals has received little attention. The effects of Pb(II) and Zn(II) contamination on the adsorption, desorption and degradation of Bt toxin identical to Bt transgenic poplar in black soil were studied. The results showed that the adsorption of Bt toxin was enhanced and the desorption of Bt toxin was inhibited in black soil by Pb(II) and Zn(II) at concentrations between 0 and 1 mmol/L, and the effect of Pb(II) on Bt toxin was greater than that of Zn(II). In the presence of heavy metal ions, the Cry1Ac toxin molecules are oriented with domain I toward soil particles through the metal ion bridge. The promoting mechanism of Bt toxin adsorption by heavy metal ions in black soil is mainly attributed to cation-controlled electrostatic attraction (CCEA), which is different from patch-controlled electrostatic attraction (PCEA). With the increase in soil concentration from 1 to 4 mg/mL, the adsorption amount of Bt toxin showed a downward trend, and both Pb(II) and Zn(II) had the maximal promotion effect when the soil concentration was 2 mg/mL. The promoting effect of Zn(II) on the adsorption of Bt toxin increased with the increased temperature (5-45 °C), but the promoting effect of Pb(II) was maximal at 25 °C. Both Pb(II) and Zn(II) affected the degradation characteristics of Bt toxin in black soil. For the lead-contaminated black soil, the residual amount of Bt toxin increased in the early stage but decreased in the later stage compared to the control soil. For the zinc-contaminated black soil, the residual amount of Bt toxin decreased compared to the control soil except between the second and tenth days. In this study, it was observed that Bt toxin was degraded rapidly in the early stage, followed by a large amount of released Bt toxin and slow degradation in the middle and late stages.
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Li Y, Koopal LK, Tan W, Chai Y, Chen Y, Wu C, Tang X. Effect of humic acid on lysozyme interaction with montmorillonite and kaolinite. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 834:155370. [PMID: 35460783 DOI: 10.1016/j.scitotenv.2022.155370] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 04/11/2022] [Accepted: 04/14/2022] [Indexed: 06/14/2023]
Abstract
Humic acid (HA) as a soil natural organic matter (NOM) can participate in the interaction between proteins and clay minerals, depending on clay type, HA and protein content, and solution conditions. The effect of HA on the interaction of lysozyme (LSZ) with kaolinite (Kao) and montmorillonite (Mont) was investigated at (initial) pHi 5 and 8. In the solutions containing both HA and LSZ, HA/LSZ complexes were formed with a net charge density depending on pH and HA/LSZ mass ratio f. LSZ adsorption on clays in the presence of HA is dominated by adsorption of HA/LSZ complexes. The HA/LSZ mass ratio (fIEP,pHi) at the isoelectric point (IEP) is pH dependent. At f <fIEP,pHi the HA/LSZ complexes are positively charged and adsorb well to the negatively charged Mont and Kao surface fractions. The adsorption levels on Mont are considerably larger than on Kao, which is mainly due to the much larger area fraction of modestly hydrophobic basal plates of Mont. The presence of HA increased the plateau adsorption of LSZ on Kao and Mont for both pHi values, and the LSZ adsorption increased with increasing HA content and pHi values due to a decreasing mutual repulsion of the bound HA/LSZ complexes. At pHi 8 complications arose for low initial LSZ concentrations, for f <fIEP,pHi the HA/LSZ complexes were only weakly positive and formed dispersed aggregates and for f >fIEP,pHi the HA/LSZ complexes were negative, both conditions caused relatively high equilibrium concentrations of LSZ in solution that decreased with increasing initial LSZ concentration. The present results enhance our insight in protein soil interactions for the case that clay particles are brought in contact with aqueous solutions that contain modest amounts of both NOM and protein and stress the importance of the NOM/protein mass ratio and solution pH.
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Affiliation(s)
- Yan Li
- Institute of Environment Resource and Soil Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; National Agricultural Experimental Station for Soil Quality, Jiaxing 314000, China.
| | - Luuk K Koopal
- Physical Chemistry and Soft Matter, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, the Netherlands
| | - Wenfeng Tan
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Yanjun Chai
- Key Laboratory of Recycling and Ecological Treatment of Waste Biomass of Zhejiang Province, School of Environment and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, China
| | - Yi Chen
- Institute of Environment Resource and Soil Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; National Agricultural Experimental Station for Soil Quality, Jiaxing 314000, China
| | - Chunyan Wu
- Institute of Environment Resource and Soil Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; National Agricultural Experimental Station for Soil Quality, Jiaxing 314000, China
| | - Xu Tang
- Institute of Environment Resource and Soil Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; National Agricultural Experimental Station for Soil Quality, Jiaxing 314000, China
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Liu J, Liang YS, Hu T, Zeng H, Gao R, Wang L, Xiao YH. Environmental fate of Bt proteins in soil: Transport, adsorption/desorption and degradation. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 226:112805. [PMID: 34592526 DOI: 10.1016/j.ecoenv.2021.112805] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 09/05/2021] [Accepted: 09/16/2021] [Indexed: 05/26/2023]
Abstract
During the production and application of Bacillus thuringiensis (Bt) transgenic crops, large doses of insecticidal Bt toxic proteins are expressed continuously. The multi-interfacial behaviors of Bt proteins entering the environment in multi-media affects their states of existence transformation, transport and fate as well as biological and ecological impacts. Because both soil matrix and organisms will be exposed to Bt proteins to a certain extent, knowledge of the multi-interfacial behaviors and affecting factors of Bt proteins are vital not only for understanding the source-sink distribution mechanisms, predicting their bio-availability, but also for exploring the soil safety and environmental problems caused by the interaction between Bt proteins and soil matrix. This review summarized and analyzed various internal and external factors that affect the adsorption/ desorption and degradation of Bt proteins in the environment, so as to understand the multi-interfacial behaviors of Bt proteins. In addition, the reasons of concentration changes of Bt proteins in soil are discussed. This review will also discuss the existing knowledge of the combined effects of Bt proteins and other pollutants in environment. Finally, discussing the factors that should be considered when assessing the environmental risk of Bt proteins, thus to further improve the understanding of the environmental fate of Bt proteins.
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Affiliation(s)
- Jiao Liu
- College of Resources and Environment, Hunan Agricultural University and Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Changsha 410128, PR China
| | - Yun-Shan Liang
- College of Resources and Environment, Hunan Agricultural University and Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Changsha 410128, PR China; College of Bioscience and Biotechnology, Hunan Agricultural University and Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production, Changsha 410128, PR China.
| | - Teng Hu
- College of Resources and Environment, Hunan Agricultural University and Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Changsha 410128, PR China
| | - Hong Zeng
- College of Resources and Environment, Hunan Agricultural University and Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Changsha 410128, PR China
| | - Rong Gao
- College of Resources and Environment, Hunan Agricultural University and Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Changsha 410128, PR China; College of Bioscience and Biotechnology, Hunan Agricultural University and Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production, Changsha 410128, PR China
| | - Li Wang
- College of Resources and Environment, Hunan Agricultural University and Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Changsha 410128, PR China
| | - Yun-Hua Xiao
- College of Bioscience and Biotechnology, Hunan Agricultural University and Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production, Changsha 410128, PR China
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Miao S, Yuan X, Liang Y, Wang H, Leng L, Wu Z, Jiang L, Li Y, Mo D, Zeng G. In situ surface transfer process of Cry1Ac protein on SiO 2: The effect of biosurfactants for desorption. JOURNAL OF HAZARDOUS MATERIALS 2018; 341:150-158. [PMID: 28777960 DOI: 10.1016/j.jhazmat.2017.07.058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 07/09/2017] [Accepted: 07/22/2017] [Indexed: 06/07/2023]
Abstract
Genetically modified Bacillus thuringiensis (Bt) crops, which have been widely used in agricultural transgenic plants, express insecticidal Cry proteins and release the toxin into soils. Taking into consideration the environmental risk of Cry proteins, biosurfactant-rhamnolipids were applied to desorb Cry proteins from soil environment, which has not been elucidated before. Quartz crystal microbalance with dissipation (QCM-D) was used in this article to investigate the adsorption and desorption behaviors of Cry1Ac on SiO2 surface (model soil). Results showed that patch-controlled electrostatic attraction (PCEA) governed Cry1Ac adsorption to SiO2, and the solution pH or ionic strength can affect PCEA. The adsorption kinetics could be fitted by the pseudo-second-order model, and the adsorption isotherm was fitted to Langmuir model with correlation coefficients higher than 0.999. The desorption characteristics of Cry1Ac from SiO2 were assessed in the presence of mono-rhamnolipid, di-rhamnolipid or complex-rhamnolipid. Mono-rhamnolipid exhibited the most significant positive effect on desorption performance. With a complete removal of Cry1Ac reached when mono-rhamnolipid concentration was up to 50mgL-1. Additionally, the desorption was enhanced at alkaline pH range, and Cry1Ac can be completely and rapidly desorbed by rhamnolipids from SiO2 at ionic strength of 5×10-2M.
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Affiliation(s)
- Shuzhou Miao
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Xingzhong Yuan
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
| | - Yunshan Liang
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, 410128, PR China; Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Changsha, 410128, PR China
| | - Hou Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Lijian Leng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Zhibin Wu
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Longbo Jiang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Yifu Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Dan Mo
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
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Kolman K, Makowski MM, Golriz AA, Kappl M, Pigłowski J, Butt HJ, Kiersnowski A. Adsorption, aggregation, and desorption of proteins on smectite particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:11650-11659. [PMID: 25216210 DOI: 10.1021/la502840s] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report on adsorption of lysozyme (LYS), ovalbumin (OVA), or ovotransferrin (OVT) on particles of a synthetic smectite (synthetic layered aluminosilicate). In our approach we used atomic force microscopy (AFM) and quartz crystal microbalance (QCM) to study the protein-smectite systems in water solutions at pH ranging from 4 to 9. The AFM provided insights into the adhesion forces of protein molecules to the smectite particles, while the QCM measurements yielded information about the amounts of the adsorbed proteins, changes in their structure, and conditions of desorption. The binding of the proteins to the smectite surface was driven mainly by electrostatic interactions, and hence properties of the adsorbed layers were controlled by pH. At high pH values a change in orientation of the adsorbed LYS molecules and a collapse or desorption of OVA layer were observed. Lowering pH to the value ≤ 4 caused LYS to desorb and swelling the adsorbed OVA. The stability of OVT-smectite complexes was found the lowest. OVT revealed a tendency to desorb from the smectite surface at all investigated pH. The minimum desorption rate was observed at pH close to the isoelectric point of the protein, which suggests that nonspecific interactions between OVT and smectite particles significantly contribute to the stability of these complexes.
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Affiliation(s)
- Krzysztof Kolman
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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Assifaoui A, Huault L, Maissiat C, Roullier-Gall C, Jeandet P, Hirschinger J, Raya J, Jaber M, Lambert JF, Cayot P, Gougeon RD, Loupiac C. Structural studies of adsorbed protein (betalactoglobulin) on natural clay (montmorillonite). RSC Adv 2014. [DOI: 10.1039/c4ra11607k] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Adsorption of betalactoglobulin on montmorillonite leads to structural changes of the protein accompanied by a partial exfoliation of clay.
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Affiliation(s)
- Ali Assifaoui
- UMR PAM Université de Bourgogne/AgroSup Dijon
- PAPC Team
- 21000 Dijon, France
| | - Lucie Huault
- UMR PAM Université de Bourgogne/AgroSup Dijon
- PAPC Team
- 21000 Dijon, France
| | - Cyrielle Maissiat
- UMR PAM Université de Bourgogne/AgroSup Dijon
- PAPC Team
- 21000 Dijon, France
| | | | - Philippe Jeandet
- Laboratoire de Stress
- Défenses et Reproduction des Plantes
- Université de Reims Champagne-Ardenne
- UFR Sciences Exactes et Naturelles
- Unité de Recherche Vigne et Vins de Champagne – EA 4707
| | - Jérôme Hirschinger
- Institut de Chimie
- UMR 7177 CNRS
- Université de Strasbourg
- 67008 Strasbourg, France
| | - Jésus Raya
- Institut de Chimie
- UMR 7177 CNRS
- Université de Strasbourg
- 67008 Strasbourg, France
| | - Maguy Jaber
- Laboratoire d'Archéologie Moléculaire et Structurale (UMR 8220 CNRS)
- UPMC Université Paris 6
- Paris, France
| | - Jean-François Lambert
- Laboratoire de Réactivité de Surface (UMR 7197 CNRS)
- UPMC Université Paris 6
- 94200 Ivry-sur-Seine, France
| | - Philippe Cayot
- UMR PAM Université de Bourgogne/AgroSup Dijon
- PAPC Team
- 21000 Dijon, France
| | - Régis D. Gougeon
- UMR PAM Université de Bourgogne/AgroSup Dijon
- PAPC Team
- 21000 Dijon, France
| | - Camille Loupiac
- UMR PAM Université de Bourgogne/AgroSup Dijon
- PAPC Team
- 21000 Dijon, France
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Fate of Bacillus thuringiensis subsp. israelensis in the field: evidence for spore recycling and differential persistence of toxins in leaf litter. Appl Environ Microbiol 2012; 78:8362-7. [PMID: 23001669 DOI: 10.1128/aem.02088-12] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus thuringiensis subsp. israelensis is a bioinsecticide increasingly used worldwide for mosquito control. Despite its apparent low level of persistence in the field due to the rapid loss of its insecticidal activity, an increasing number of studies suggested that the recycling of B. thuringiensis subsp. israelensis can occur under specific, unknown conditions. Decaying leaf litters sampled in mosquito breeding sites in the French Rhône-Alpes region several months after a treatment were shown to exhibit a high level of larval toxicity and contained large amounts of spores. In the present article, we show that the high concentration of toxins found in these litters is consistent with spore recycling in the field, which gave rise to the production of new crystal toxins. Furthermore, in these toxic leaf litter samples, Cry4Aa and Cry4Ba toxins became the major toxins instead of Cyt1Aa in the commercial mixture. In a microcosm experiment performed in the laboratory, we also demonstrated that the toxins, when added in their crystal form to nontoxic leaf litter, exhibited patterns of differential persistence consistent with the proportions of toxins observed in the field-collected toxic leaf litter samples (Cry4 > Cry11 > Cyt). These results give strong evidence that B. thuringiensis subsp. israelensis recycled in specific breeding sites containing leaf litters, and one would be justified in asking whether mosquitoes can become resistant when exposed to field-persistent B. thuringiensis subsp. israelensis for several generations.
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Sander M, Tomaszewski JE, Madliger M, Schwarzenbach RP. Adsorption of insecticidal Cry1Ab protein to humic substances. 1. Experimental approach and mechanistic aspects. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:9923-9931. [PMID: 22862304 DOI: 10.1021/es3022478] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Adsorption is a key process affecting the fate of insecticidal Cry proteins (Bt toxins), produced by genetically modified Bt crops, in soils. However, the mechanisms of adsorption to soil organic matter (SOM) remain poorly understood. This work assesses the forces driving the adsorption of Cry1Ab to Leonardite humic acid (LHA), used as a model for SOM. We studied the effects of solution pH and ionic strength (I) on adsorption using a quartz crystal microbalance with dissipation monitoring and optical waveguide lightmode spectroscopy. Initial Cry1Ab adsorption rates were close to diffusion-limited and resulted in extensive adsorption, even at pH >6, at which LHA and Cry1Ab carry negative net charges. Adsorption increased with decreasing I at pH >6, indicating Cry1Ab-LHA patch-controlled electrostatic attraction via positively charged domains of Cry1Ab. Upon rinsing, only a fraction of Cry1Ab desorbed, suggesting a range of interaction energies of Cry1Ab with LHA. Different interaction energies likely resulted from nonuniformity in the LHA surface polarity, with higher Cry1Ab affinities to more apolar LHA regions due to the hydrophobic effect. Contributions from the hydrophobic effect were substantiated by comparison of the adsorption of Cry1Ab and the reference proteins albumin and lysozyme to LHA and to apolar and polar model surfaces.
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Affiliation(s)
- Michael Sander
- Institute of Biogeochemistry and Pollutant Dynamics (IBP), Swiss Federal Institute of Technology, ETH Zurich, Zurich, Switzerland.
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Kolman K, Steffen W, Bugla-Płoskońska G, Skwara A, Pigłowski J, Butt HJ, Kiersnowski A. Exfoliation of montmorillonite in protein solutions. J Colloid Interface Sci 2012; 374:135-40. [DOI: 10.1016/j.jcis.2012.02.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 02/05/2012] [Accepted: 02/06/2012] [Indexed: 11/25/2022]
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