1
|
Schniete JK, Brüser T, Horn MA, Tschowri N. Specialized biopolymers: versatile tools for microbial resilience. Curr Opin Microbiol 2024; 77:102405. [PMID: 38070462 DOI: 10.1016/j.mib.2023.102405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 11/07/2023] [Accepted: 11/09/2023] [Indexed: 02/12/2024]
Abstract
Bacteria produce a wide range of specialized biopolymers that can be classified into polysaccharides, polyamides, and polyesters and are considered to fulfill storage functions. In this review, we highlight recent developments in the field linking metabolism of biopolymers to stress and signaling physiology of the producers and demonstrating that biopolymers contribute to bacterial stress resistance and shape structure and composition of microenvironments. While specialized biopolymers are currently the focus of much attention in biotechnology as innovative and biodegradable materials, our understanding about the regulation and functions of these valuable compounds for the producers, microbial communities, and our environment is still very limited. Addressing open questions about signals, mechanisms, and functions in the area of biopolymers harbors potential for exciting discoveries with high relevance for biotechnology and fundamental research.
Collapse
Affiliation(s)
- Jana K Schniete
- Institute of Microbiology, Leibniz Universität Hannover, 30419 Hannover, Germany.
| | - Thomas Brüser
- Institute of Microbiology, Leibniz Universität Hannover, 30419 Hannover, Germany
| | - Marcus A Horn
- Institute of Microbiology, Leibniz Universität Hannover, 30419 Hannover, Germany
| | - Natalia Tschowri
- Institute of Microbiology, Leibniz Universität Hannover, 30419 Hannover, Germany
| |
Collapse
|
2
|
Zhang YX, Li YX, Zhang W, Niu Y, Zeng RJ. Enrichment of biofertilizer-type hydrogen-oxidizing bacteria on urea containing Cu(II). ENVIRONMENTAL RESEARCH 2023; 236:116831. [PMID: 37543126 DOI: 10.1016/j.envres.2023.116831] [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: 05/31/2023] [Revised: 07/27/2023] [Accepted: 08/03/2023] [Indexed: 08/07/2023]
Abstract
With the utilization of pesticides and fertilizers (e.g. urea), the presence of nitrogen and heavy metals (e.g. copper) can enter and pollute the environment. Biofertilizers can be used to replace chemical fertilizers to increase crop yields and reduce environmental stress. The utilization of hydrogen-oxidizing bacteria (HOB) to be biofertilizers has recently attracted more attention. However, the enrichment of HOB on urea and the effect of copper are undetermined. HOB were successfully enriched using urea in this investigation. The average urea conversion rate (AUCR) was 180.08 mgN/L/d with a hydraulic retention time of 10 h. Microbial community (R1) was dominated by Hydrogenophaga (83.92%), a biofertilizer-type HOB. After addition of 5.47 mg/L Cu2+, the AUCR was decreased by 16%-151.18 mgN/L/d, and the growth of HOB was inhibited by 48%. Meanwhile, inhibition was also reflected by the increase of polysaccharide content (20.27 ± 0.57 to 33.45 ± 2.53 mg/gVSS) and protein content (106.19 ± 19.39 to 125.14 ± 24.73 mg/gVSS) of extracellular polymeric substances in the HOB. The resulting microbial community (R2) was changed to Azospiralium-dominated flora (91.33%). Both enriched microbial communities (R1 and R2) exhibited the abilities of ACC degradation and phosphate solubilization. This study demonstrates that employing urea can directly enrich biofertilizer-type HOB and copper-tolerant HOB can be obtained in a 5.47 mg/L Cu2+ environment. The results provide potential methods to obtain biofertilizer from copper-containing urea wastewater via HOB.
Collapse
Affiliation(s)
- Yi-Xin Zhang
- Centre of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Yong-Xin Li
- Centre of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Wei Zhang
- Centre of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; College of Resources and Environment, Anhui Agricultural University, Hefei, China
| | - Yun Niu
- Centre of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Raymond Jianxiong Zeng
- Centre of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
| |
Collapse
|
3
|
Xu Z, Huang J, Chu Z, Meng F, Liu J, Li K, Chen X, Jiang Y, Ban Y. Plant and microbial communities responded to copper and/or tetracyclines in mycorrhizal enhanced vertical flow constructed wetlands microcosms with Canna indica L. JOURNAL OF HAZARDOUS MATERIALS 2023; 451:131114. [PMID: 36870129 DOI: 10.1016/j.jhazmat.2023.131114] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 02/17/2023] [Accepted: 02/27/2023] [Indexed: 06/18/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) play a significant role in pollutants removal in constructed wetlands (CWs). However, the purification effects of AMF on combined copper (Cu) and tetracycline (TC) pollution in CWs remains unknown. This study investigated the growth, physiological characteristics and AMF colonization of Canna indica L. living in vertical flow CWs (VFCWs) treated for Cu and/or TC pollution, the purification effects of AMF enhanced VFCWs on Cu and TC, and the microbial community structures. The results showed that (1) Cu and TC inhibited plant growth and decreased AMF colonization; (2) the removal rates of TC and Cu by VFCWs were 99.13-99.80% and 93.17-99.64%, respectively; (3) the growth, Cu and TC uptakes of C. indica and Cu removal rates were enhanced by AMF inoculation; (4) TC and Cu stresses reduced and AMF inoculation increased bacterial operational taxonomic units (OTUs) in the VFCWs, Proteobacteria, Bacteroidetes, Firmicutes and Acidobacteria were the dominant bacteria, and AMF inoculation decreased the relative abundance of Novosphingobium and Cupriavidus. Therefore, AMF could enhance the pollutants purification in VFCWs by promoting plant growth and altering the microbial community structures.
Collapse
Affiliation(s)
- Zhouying Xu
- School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, Hubei, China
| | - Jun Huang
- School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, Hubei, China
| | - Zhenya Chu
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, Hubei, China
| | - Fake Meng
- School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, Hubei, China
| | - Jianjun Liu
- POWERCHINA Huadong Engineering Corporation Limited, Hangzhou 311122, Zhejiang, China
| | - Kaiguo Li
- School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, Hubei, China
| | - Xi Chen
- School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, Hubei, China
| | - Yinghe Jiang
- School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, Hubei, China
| | - Yihui Ban
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, Hubei, China.
| |
Collapse
|
4
|
Mrazova K, Bacovsky J, Sedrlova Z, Slaninova E, Obruca S, Fritz I, Krzyzanek V. Urany-Less Low Voltage Transmission Electron Microscopy: A Powerful Tool for Ultrastructural Studying of Cyanobacterial Cells. Microorganisms 2023; 11:888. [PMID: 37110311 PMCID: PMC10146862 DOI: 10.3390/microorganisms11040888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 03/27/2023] [Accepted: 03/28/2023] [Indexed: 03/31/2023] Open
Abstract
Sample preparation protocols for conventional high voltage transmission electron microscopy (TEM) heavily rely on the usage of staining agents containing various heavy metals, most commonly uranyl acetate and lead citrate. However high toxicity, rising legal regulations, and problematic waste disposal of uranyl acetate have increased calls for the reduction or even complete replacement of this staining agent. One of the strategies for uranyless imaging is the employment of low-voltage transmission electron microscopy. To investigate the influence of different imaging and staining strategies on the final image of cyanobacterial cells, samples stained by uranyl acetate with lead citrate, as well as unstained samples, were observed using TEM and accelerating voltages of 200 kV or 25 kV. Moreover, to examine the possibilities of reducing chromatic aberration, which often causes issues when imaging using electrons of lower energies, samples were also imaged using a scanning transmission electron microscopy at 15 kV accelerating voltages. The results of this study demonstrate that low-voltage electron microscopy offers great potential for uranyless electron microscopy.
Collapse
Affiliation(s)
- Katerina Mrazova
- Institute of Scientific Instruments of the Czech Academy of Sciences, v.v.i., Kralovopolska 147, 612 64 Brno, Czech Republic;
| | - Jaromir Bacovsky
- Delong Instruments a.s., Palackeho Trida 3019/153 b, 612 00 Brno, Czech Republic;
| | - Zuzana Sedrlova
- Department of Food Chemistry and Biotechnology, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic; (Z.S.); (E.S.); (S.O.)
| | - Eva Slaninova
- Department of Food Chemistry and Biotechnology, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic; (Z.S.); (E.S.); (S.O.)
| | - Stanislav Obruca
- Department of Food Chemistry and Biotechnology, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic; (Z.S.); (E.S.); (S.O.)
| | - Ines Fritz
- Institute of Environmental Biotechnology, Department of Agrobiotechnology, IFA-Tulln, University of Natural Resources and Life Sciences, Konrad-Lorenz-Strase 20, 3430 Tulln an der Donau, Austria;
| | - Vladislav Krzyzanek
- Institute of Scientific Instruments of the Czech Academy of Sciences, v.v.i., Kralovopolska 147, 612 64 Brno, Czech Republic;
| |
Collapse
|
5
|
Optimization of Growth Conditions to Enhance PHA Production by Cupriavidus necator. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation8090451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The accumulation of polyhydroxyalkanoates (PHAs) by microorganisms usually occurs in response to environmental stress conditions. Therefore, it is advantageous to choose two-step cultivation. The first phase is aimed at maximizing biomass production, and only in the second phase, after setting the suitable conditions, PHA production starts. The aim of this work was to optimize the composition of the minimal propagation medium used for biomass production of Cupriavidus necator DSM 545 using the response surface methodology (RSM). Based on the results from the search for optimization limits, the glucose concentration, the ammonium sulfate concentration and the phosphate buffer molarity were chosen as independent variables. The optimal values were found as follows: the glucose concentration 10.8 g/L; the ammonium sulfate concentration 0.95 g/L; and the phosphate buffer molarity 60.2 mmol/L. The predicted biomass concentration was 4.54 g/L, and the verified value was at 4.84 g/L. Although this work was primarily focused on determining the optimal composition of the propagation medium, we also evaluated the optimal composition of the production medium and found that the optimal glucose concentration was 6.7 g/L; the ammonium sulfate concentration 0.60 g/L; and the phosphate buffer molarity 20 mmol/L. The predicted PHB yield was 54.7% (w/w) of dry biomass, and the verified value was 49.1%.
Collapse
|