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Che S, Xu Y, Qin X, Tian S, Wang J, Zhou X, Cao Z, Wang D, Wu M, Wu Z, Yang M, Wu L, Yang X. Building microbial consortia to enhance straw degradation, phosphorus solubilization, and soil fertility for rice growth. Microb Cell Fact 2024; 23:232. [PMID: 39169403 PMCID: PMC11337586 DOI: 10.1186/s12934-024-02503-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2024] [Accepted: 08/07/2024] [Indexed: 08/23/2024] Open
Abstract
Straw pollution and the increasing scarcity of phosphorus resources in many regions of China have had severe impacts on the growing conditions for crop plants. Using microbial methods to enhance straw decomposition rate and phosphorus utilization offers effective solutions to address these problems. In this study, a microbial consortium 6 + 1 (consisting of a straw-degrading bacterium and a phosphate-solubilizing bacterium) was formulated based on their performance in straw degradation and phosphorus solubilization. The degradation rate of straw by 6 + 1 microbial consortium reached 48.3% within 7 days (The degradation ability was 7% higher than that of single bacteria), and the phosphorus dissolution rate of insoluble phosphorus reached 117.54 mg·L- 1 (The phosphorus solubilization ability was 29.81% higher than that of single bacteria). In addition, the activity of lignocellulosic degrading enzyme system was significantly increased, the activities of endoglucanase, β-glucosidase and xylanase in the microbial consortium were significantly higher than those in the single strain (23.16%, 28.02% and 28.86%, respectively). Then the microbial consortium was processed into microbial agents and tested in rice pots. The results showed that the microbial agent significantly increased the content of organic matter, available phosphorus and available nitrogen in the soil. Ongoing research focuses on the determination of the effects and mechanisms of a functional hybrid system of straw degradation and phosphorus removal. The characteristics of the two strains are as follows: Straw-degrading bacteria can efficiently degrade straw to produce glucose-based carbon sources when only straw is used as a carbon source. Phosphate-solubilizing bacteria can efficiently use glucose as a carbon source, produce organic acids to dissolve insoluble phosphorus and consume glucose at an extremely fast rate. The analysis suggests that the microbial consortium 6 + 1 outperformed individual strains in terms of both performance and application effects. The two strains within the microbial consortium promote each other during their growth processes, resulting in a significantly higher rate of carbon source consumption compared to the individual strains in isolation. This increased demand for carbon sources within the growth system facilitates the degradation of straw by the strains. At the same time, the substantial carbon consumption during the metabolic process generated a large number of organic acids, leading to the solubilization of insoluble phosphorus. It also provides a basis for the construction of this type of microbial consortium.
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Affiliation(s)
- Songhao Che
- College of Life Science, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Yufeng Xu
- College of Life Science, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Xueting Qin
- College of Life Science, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Shiqi Tian
- College of Life Science, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Jianing Wang
- College of Life Science, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Xueying Zhou
- College of Life Science, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Zhenning Cao
- College of Life Science, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Dongchao Wang
- Faculty of Agronomy, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Meikang Wu
- Faculty of Agronomy, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Zhihai Wu
- Faculty of Agronomy, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Meiying Yang
- College of Life Science, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Lei Wu
- College of Life Science, Jilin Agricultural University, Changchun, 130118, Jilin, China.
| | - Xue Yang
- College of Life Science, Jilin Agricultural University, Changchun, 130118, Jilin, China.
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Yue J, Li T, Tian J, Ge F, Li F, Liu Y, Zhang D, Li J. Penicillium oxalicum induced phosphate precipitation enhanced cadmium (Cd) immobilization by simultaneously accelerating Cd biosorption and biomineralization. JOURNAL OF HAZARDOUS MATERIALS 2024; 470:134306. [PMID: 38626684 DOI: 10.1016/j.jhazmat.2024.134306] [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: 01/10/2024] [Revised: 03/21/2024] [Accepted: 04/11/2024] [Indexed: 04/18/2024]
Abstract
Soil cadmium (Cd) is immobilized by the progressing biomineralization process as microbial induced phosphate precipitation (MIPP), which is regulated by phosphate (P) solubilizing microorganisms and P sources. However, little attention has been paid to the implications of Cd biosorption during MIPP. In this study, the newly isolated Penicillium oxalicum could immobilize 5.4-12.6 % of Cd2+, while the presence of hydroxyapatite (HAP) considerably enhanced Cd2+ immobilization in P. oxalicum and reached over 99 % Cd2+ immobilization efficiency within 7 days. Compared to P. oxalicum mono inoculation, MIPP dramatically boosted Cd biosorption and biomineralization efficiency by 71 % and 16 % after 96 h cultivation, respectively. P. oxalicum preferred to absorbing Cd2+ and reaching maximum Cd2+ biosorption efficiency of 87.8 % in the presence of HAP. More surface groups in P. oxalicum and HAP mineral involved adsorption which resulted in the formation of Cd-apatite [Ca8Cd2(PO4)6(OH)2] via ion exchange. Intracellular S2-, secreted organic acids and soluble P via HAP solubilization complexed with Cd2+, progressively mineralized into Cd5(PO4)3OH, Cd(H2PO4)2, C4H6CdO4 and CdS. These results suggested that Cd2+ immobilization was enhanced simultaneously by the accelerated biosorption and biomineralization during P. oxalicum induced P precipitation. Our findings revealed new mechanisms of Cd immobilization in MIPP process and offered clues for remediation practices at metal contaminated sites.
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Affiliation(s)
- Jiaru Yue
- Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan, China; Hunan Provincial University Key Laboratory for Environmental and Ecological Health, Xiangtan University, Xiangtan, China
| | - Ting Li
- Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan, China; Hunan Provincial University Key Laboratory for Environmental and Ecological Health, Xiangtan University, Xiangtan, China
| | - Jiang Tian
- Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan, China; Hunan Provincial University Key Laboratory for Environmental and Ecological Health, Xiangtan University, Xiangtan, China.
| | - Fei Ge
- Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan, China; Hunan Provincial University Key Laboratory for Environmental and Ecological Health, Xiangtan University, Xiangtan, China
| | - Feng Li
- Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan, China; Hunan Provincial University Key Laboratory for Environmental and Ecological Health, Xiangtan University, Xiangtan, China
| | - Yun Liu
- Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan, China; Hunan Provincial University Key Laboratory for Environmental and Ecological Health, Xiangtan University, Xiangtan, China
| | - Dayi Zhang
- College of New Energy and Environment, Jilin University, Changchun 130021, China; Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun 130021, China
| | - Jingwei Li
- Vegetable Industry Research Institute, Guizhou University, Guiyang 550000, Guizhou, China.
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Huang H, Wang K, Li S, Liang K, Dai J, Jian J, Li Y, Liu H, Xu H. Different survival strategies of the phosphate-mineralizing bacterium Enterobacter sp. PMB-5 in response to cadmium stress: Biomineralization, biosorption, and bioaccumulation. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133284. [PMID: 38134699 DOI: 10.1016/j.jhazmat.2023.133284] [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: 09/19/2023] [Revised: 11/24/2023] [Accepted: 12/13/2023] [Indexed: 12/24/2023]
Abstract
The phosphate-mineralizing bacteria (PMBs) has shown great potential as a sustainable solution to support pollution remediation through its induced mineralization capacity. However, few studies have been conducted on the mechanism of cadmium (Cd) tolerance in PMBs. In this study, a PMB strain, Enterobacter sp. PMB-5, screened from Cd-contaminated rhizosphere soil, has high resistance to Cd (540 - 1220 mg/L) and solubilized phosphate (232.08 mg/L). The removal experiments showed that the strain PMB-5 removed 71.69-98.24% and 34.83-76.36% of Cd with and without biomineralization, respectively. The characterization result of SEM, EDS, TEM, XPS and XRD revealed that PMB-5 induced Cd to form amorphous phosphate precipitation through biomineralization and adopted different survival strategies, including biomineralization, bioaccumulation, and biosorption to resistance Cd in the microbial induced phosphate precipitation (MIPP) system and the non-MIPP system, respectively. Moreover, the results of whole genome sequencing and qRT-PCR indicated that phosphorus metabolism genes such as pst, pit, phn, ugp, ppk, etc. and heavy metal tolerance genes (including ion transport, ion efflux, redox, antioxidant stress), such as czcD, zntA, mgtA, mgtC, katE, SOD2, dsbA, cysM, etc. were molecular for the PMB-5 mineralization and Cd tolerance of PMB-5. Together, our findings suggested Enterobacter sp. PMB-5 is a potential target for developing more effective bioinoculants for Cd contamination remediation.
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Affiliation(s)
- Huayan Huang
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Keke Wang
- Sichuan Academy of Eco-Environmental Sciences, Chengdu 610066, PR China
| | - Shiyao Li
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Ke Liang
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Jingtong Dai
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Jiannan Jian
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Yongyun Li
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Huakang Liu
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China; Key Laboratory of Environment Protection, Soil ecological protection and pollution control, Sichuan University & Department of Ecology and Environment of Sichuan, Chengdu 610065, Sichuan, PR China.
| | - Heng Xu
- Key Laboratory of Bio-resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China; Key Laboratory of Environment Protection, Soil ecological protection and pollution control, Sichuan University & Department of Ecology and Environment of Sichuan, Chengdu 610065, Sichuan, PR China.
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Zhang H, Zhang K, Duan Y, Sun X, Lin L, An Q, Altaf MM, Zhu Z, Liu F, Jiao Y, Yin J, Xie C, Wang B, Feng H, Zhang X, Li D. Effect of EDDS on the rhizosphere ecology and microbial regulation of the Cd-Cr contaminated soil remediation using king grass combined with Piriformospora indica. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133266. [PMID: 38118201 DOI: 10.1016/j.jhazmat.2023.133266] [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: 08/24/2023] [Revised: 12/08/2023] [Accepted: 12/12/2023] [Indexed: 12/22/2023]
Abstract
The negative impacts of soil heavy metals composite pollution on agricultural production and human health are becoming increasingly prevalent. The applications of green chelating agents and microorganisms have emerged as promising alternate methods for enhancing phytoremediation. The regulatory effects of root secretion composition, microbial carbon source utilization, key gene expression, and soil microbial community structure were comprehensively analyzed through a combination of HPLC, Biolog EcoPlates, qPCR, and high-throughput screening techniques. The application of EDDS resulted in a favorable rhizosphere ecological environment for the king grass Piriformospora indica, characterized by a decrease in soil pH by 0.41 units, stimulation of succinic acid and fumaric acid secretion, and an increase in carbon source metabolic activity of amino acids and carbohydrates. Consequently, this improvement enhanced the bioavailability of Cd/Cr and increased the biomass of king grass by 25.7%. The expression of dissimilatory iron-reducing bacteria was significantly upregulated by 99.2%, while there was no significant difference in Clostridium abundance. Furthermore, the richness of the soil rhizosphere fungal community (Ascomycota: 45.8%, Rozellomycota: 16.7%) significantly increased to regulate the proportion of tolerant microbial dominant groups, promoting the improvement of Cd/Cr removal efficiency (Cd: 23.4%, Cr: 18.7%). These findings provide a theoretical basis for the sustainable development of chelating agent-assisted plants-microorganisms combined remediation of heavy metals in soil.
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Affiliation(s)
- Haixiang Zhang
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Kailu Zhang
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Yali Duan
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Xiaoyan Sun
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Li Lin
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi) / Guangxi Key Laboratory of Sugarcane Genetic Improvement, Ministry of Agriculture and Rural Affairs, Nanning 530007, China
| | - Qianli An
- State Key Laboratory of Rice Biology and Breeding, Key Laboratory of Molecular Biology of Crop Pathogens and Insects Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310000, China
| | - Muhammad Mohsin Altaf
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Zhiqiang Zhu
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China.
| | - Fan Liu
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Yangqiu Jiao
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Jing Yin
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Can Xie
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Baijie Wang
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Huiping Feng
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
| | - Xin Zhang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Dong Li
- School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China; Key Laboratory for Environmental Toxicology of Haikou / Center for Eco-Environmental Restoration aboratory of Marine Resource Utilization in South China Sea / Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, Hainan University, Haikou 570228, China.
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5
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Fang Y, Yang G, Wu X, Qin B, Xie Y, Zhuang L. Sub-MIC antibiotics affect microbial ferrihydrite reduction by extracellular membrane vesicles. JOURNAL OF HAZARDOUS MATERIALS 2023; 458:131876. [PMID: 37379597 DOI: 10.1016/j.jhazmat.2023.131876] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 06/08/2023] [Accepted: 06/14/2023] [Indexed: 06/30/2023]
Abstract
Environmental concentrations of antibiotics, usually below MIC, have significant biological effects on bacterial cells. Sub-MIC antibiotics exposure induces bacteria to produce outer membrane vesicles (OMVs). Recently, OMVs is discovered as a novel pathway for dissimilatory iron reducing bacteria (DIRB) to mediate extracellular electron transfer (EET). Whether and how the antibiotic-induced OMVs modulate iron oxides reduction by DIRB have not been studied. This study showed the sub-MIC antibiotics (ampicillin or ciprofloxacin) increased OMVs secretion in Geobacter sulfurreducens, and the antibiotic-induced OMVs contained more redox active cytochromes facilitating iron oxides reduction, especially for the ciprofloxacin-induced OMVs. Deduced from a combination of electron microscopy and proteomic analysis, the influence of ciprofloxacin on SOS response triggered prophage induction and led to the formation of outer-inner membrane vesicles (OIMVs) in, which was a first report in Geobacter species. While ampicillin disrupting cell membrane integrity resulted in more formation of classic OMVs from outer membrane blebbing. The results indicated that the different structure and composition of vesicles were responsible for the antibiotic-dependent regulation on iron oxides reduction. This newly identified regulation on EET-mediated redox reactions by sub-MIC antibiotics expands our knowledge about the impact of antibiotics on microbial processes or "non-target" organisms.
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Affiliation(s)
- Yanlun Fang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Guiqin Yang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China.
| | - Xian Wu
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Baoli Qin
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Yiqiao Xie
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Li Zhuang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China.
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Ye J, Mao Y, Meng L, Li J, Li X, Xiao L, Zhang Y, Wang F, Deng H. Polycaprolactone-Modified Biochar Supported Nanoscale Zero-Valent Iron Coupling with Shewanella putrefaciens CN32 for 1,1,1-Trichloroethane Removal from Simulated Groundwater: Synthesis, Optimization, and Mechanism. Molecules 2023; 28:molecules28073145. [PMID: 37049906 PMCID: PMC10095663 DOI: 10.3390/molecules28073145] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/17/2023] [Accepted: 03/28/2023] [Indexed: 04/05/2023] Open
Abstract
1,1,1-Trichloroethane (1,1,1-TCA) is a typical organochloride solvent in groundwater that poses threats to human health and the environment due to its carcinogenesis and bioaccumulation. In this study, a novel composite with nanoscale zero-valent iron (nZVI) supported by polycaprolac-tone (PCL)-modified biochar (nZVI@PBC) was synthesized via solution intercalation and liquid-phase reduction to address the 1,1,1-TCA pollution problem in groundwater. The synergy effect and improvement mechanism of 1,1,1-TCA removal from simulated groundwater in the presence of nZVI@PBC coupling with Shewanella putrefaciens CN32 were investigated. The results were as follows: (1) The composite surface was rough and porous, and PCL and nZVI were loaded uniformly onto the biochar surface as micro-particles and nanoparticles, respectively; (2) the optimal mass ratio of PCL, biochar, and nZVI was 1:7:2, and the optimal composite dosage was 1.0% (w/v); (3) under the optimal conditions, nZVI@PBC + CN32 exhibited excellent removal performance for 1,1,1-TCA, with a removal rate of 82.98% within 360 h, while the maximum removal rate was only 41.44% in the nZVI + CN32 treatment; (4) the abundance of CN32 and the concentration of adsorbed Fe(II) in the nZVI@PBC + CN32 treatment were significantly higher than that in control treatments, while the total organic carbon (TOC) concentration first increased and then decreased during the culture process; (5) the major improvement mechanisms include the nZVI-mediated chemical reductive dechlorination and the CN32-mediated microbial dissimilatory iron reduction. In conclusion, the nZVI@PBC composite coupling with CN32 can be a potential technique to apply for 1,1,1-TCA removal in groundwater.
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Affiliation(s)
- Jing Ye
- School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai 201418, China
| | - Yacen Mao
- School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai 201418, China
| | - Liang Meng
- Key Lab of Eco-Restoration of Regional Contaminated Environment, Ministry of Education, Shenyang University, Shenyang 110044, China
- School of Environmental and Geographical Sciences, Shanghai Normal University, Shanghai 200234, China
- Yangtze River Delta Urban Wetland Ecosystem National Field Scientific Observation and Research Station, Shanghai 201722, China
- State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, Chengdu University of Technology, Chengdu 610059, China
| | - Junjie Li
- School of Environmental and Geographical Sciences, Shanghai Normal University, Shanghai 200234, China
- Yangtze River Delta Urban Wetland Ecosystem National Field Scientific Observation and Research Station, Shanghai 201722, China
| | - Xilin Li
- School of Environmental and Geographical Sciences, Shanghai Normal University, Shanghai 200234, China
- Yangtze River Delta Urban Wetland Ecosystem National Field Scientific Observation and Research Station, Shanghai 201722, China
| | - Lishan Xiao
- School of Environmental and Geographical Sciences, Shanghai Normal University, Shanghai 200234, China
- Yangtze River Delta Urban Wetland Ecosystem National Field Scientific Observation and Research Station, Shanghai 201722, China
| | - Ying Zhang
- The Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, East China Normal University, Shanghai 200241, China
| | - Fenghua Wang
- School of Geographical Sciences, Hebei Normal University, Shijiazhuang 050024, China
| | - Huan Deng
- School of Environment, Nanjing Normal University, Nanjing 210023, China
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