1
|
Hu Z, Chin Y, Yuan C, Ge Y, Hang Y, Wang D, Yao Q, Hu Y. The luxS deletion reduces the spoilage ability of Shewanella putrefaciens: An analysis focusing on quorum sensing and activated methyl cycle. Food Microbiol 2024; 120:104467. [PMID: 38431319 DOI: 10.1016/j.fm.2024.104467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/02/2024] [Accepted: 01/08/2024] [Indexed: 03/05/2024]
Abstract
The luxS mutant strains of Shewanella putrefaciens (SHP) were constructed to investigate the regulations of gene luxS in spoilage ability. The potential regulations of AI-2 quorum sensing (QS) system and activated methyl cycle (AMC) were studied by analyzing the supplementation roles of key circulating substances mediated via luxS, including S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), methionine (Met), homocysteine (Hcy) and 4,5-dihydroxy-2,3-pentanedione (DPD). Growth experiments revealed that the luxS deletion led to certain growth limitations of SHP, which were associated with culture medium and exogenous additives. Meanwhile, the decreased biofilm formation and diminished hydrogen sulfide (H2S) production capacity of SHP were observed after luxS deletion. The relatively lower total volatile base nitrogen (TVB-N) contents and higher sensory scores of fish homogenate with luxS mutant strain inoculation also indicated the weaker spoilage-inducing effects after luxS deletion. However, these deficiencies could be offset with the exogenous supply of circulating substances mentioned above. Our findings suggested that the luxS deletion would reduce the spoilage ability of SHP, which was potentially attributed to the disorder of AMC and AI-2 QS system.
Collapse
Affiliation(s)
- Zhiheng Hu
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China; United Graduate School of Agricultural Sciences, Ueda 3-8-18, Morioka, Iwate 020-8550, Japan
| | - Yaoxian Chin
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China
| | - Chunhong Yuan
- Faculty of Agriculture, Iwate University, Ueda 3-8-18, Morioka, Iwate 020-8550, Japan; Agri-Innovation Center, Iwate University, Ueda 3-8-18, Morioka, Iwate 020-8550, Japan
| | - Yingliang Ge
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China
| | - Yuyu Hang
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China
| | - Dongxue Wang
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China
| | - Qian Yao
- Key Laboratory of Medicinal and Edible Plants Resources Development of Sichuan Education Department, Sichuan Industrial Institute of Antibiotics, School of Pharmacy, Chengdu University, Chengdu 610106, China
| | - Yaqin Hu
- College of Food Science and Engineering, Hainan Tropical Ocean University, Yazhou Bay Innovation Institute, Marine Food Engineering Technology Research Center of Hainan Province, Collaborative Innovation Center of Marine Food Deep Processing, Sanya 572022, China.
| |
Collapse
|
2
|
Lou Y, Chang W, Huang L, Chen X, Hao X, Qian H, Zhang D. Influence of marine Shewanella putrefaciens and mediated calcium deposition on Q235 carbon steel corrosion. Bioelectrochemistry 2024; 157:108657. [PMID: 38335713 DOI: 10.1016/j.bioelechem.2024.108657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 01/11/2024] [Accepted: 01/24/2024] [Indexed: 02/12/2024]
Abstract
The microbiologically influenced corrosion inhibition (MICI) of Q235 carbon steel by Shewanella putrefaciens and mediated calcium deposition were investigated by regulating microbial mineralization. In a calcium-rich medium, S. putrefaciens rapidly created a protective calcium carbonate layer on the steel surface, which blocked Cl- diffusion. Without calcium, the biofilm and rust layer mitigated pitting corrosion but did not prevent Cl- penetration. Potentiodynamic polarization results indicated that the current densities (icorr values) of the corrosion produced in the S. putrefaciens-inoculated media with and without calcium were 0.4 μA/cm2 and 0.6 μA/cm2, respectively. Similarly, compared with those under sterile conditions, the corrosion inhibition rates were 92.2% and 87.4% higher, respectively. Electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SECM) confirmed that the MICI was caused by the combination of microbial aerobic respiration and the deposited layers. Even under nonbiological conditions, S. putrefaciens-induced calcium carbonate deposition inhibited corrosion.
Collapse
Affiliation(s)
- Yuntian Lou
- Beijing Advanced Innovation Center for Materials Genome Engineering, Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China; National Materials Corrosion and Protection Data Center, University of Science and Technology Beijing, Beijing 100083, China; BRI Southeast Asia Network for Corrosion and Protection (MOE), Shunde Innovation School, University of Science and Technology Beijing, Foshan 528399, China
| | - Weiwei Chang
- Beijing Advanced Innovation Center for Materials Genome Engineering, Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China; National Materials Corrosion and Protection Data Center, University of Science and Technology Beijing, Beijing 100083, China
| | - Luyao Huang
- State Key Laboratory of Advanced Power Transmission Technology, State Grid Smart Grid Research Institute Co., Ltd., Beijing 102209, China
| | - Xudong Chen
- School of Materials Science and Hydrogen Energy, Foshan University, Foshan 528000, China
| | - Xiangping Hao
- Beijing Advanced Innovation Center for Materials Genome Engineering, Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China; National Materials Corrosion and Protection Data Center, University of Science and Technology Beijing, Beijing 100083, China
| | - Hongchang Qian
- Beijing Advanced Innovation Center for Materials Genome Engineering, Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China; National Materials Corrosion and Protection Data Center, University of Science and Technology Beijing, Beijing 100083, China; BRI Southeast Asia Network for Corrosion and Protection (MOE), Shunde Innovation School, University of Science and Technology Beijing, Foshan 528399, China
| | - Dawei Zhang
- Beijing Advanced Innovation Center for Materials Genome Engineering, Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China; National Materials Corrosion and Protection Data Center, University of Science and Technology Beijing, Beijing 100083, China; BRI Southeast Asia Network for Corrosion and Protection (MOE), Shunde Innovation School, University of Science and Technology Beijing, Foshan 528399, China.
| |
Collapse
|
3
|
Cao H, Zheng X, Teng C, Xu L, Wang Y, Gai C, Ye H. Rhodobacter sphaeroides supplementation improves defense ability of Chinese mitten crab Eriocheir sinensis against Shewanella putrefaciens infection via intestinal flora and metabolism regulation. J Invertebr Pathol 2024; 204:108120. [PMID: 38679366 DOI: 10.1016/j.jip.2024.108120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 03/27/2024] [Accepted: 04/25/2024] [Indexed: 05/01/2024]
Abstract
Shewanella putrefaciens is a vital bacterial pathogen implicated in serious diseases in Chinese mitten crab Eriocheir sinensis. Yet the use of probiotics to improve the defense ability of E. sinensis against S. putrefaciens infection remains poorly understood. In the present study, the protective effect of dietary R. sphaeroides against S. putrefaciens infection in E. sinensis was evaluated through antioxidant capability, immune response, and survival under bacterial challenge assays, and its protective mechanism was further explored using a combination of intestinal flora and metabolome assays. Our results indicated that dietary R. sphaeroides could significantly improve immunity and antioxidant ability of Chinese mitten crabs, thereby strengthening their disease resistance with the relative percentage survival of 81.09% against S. putrefaciens. In addition, dietary R. sphaeroides could significantly alter the intestinal microbial composition and intestinal metabolism of crabs, causing not only the reduction of potential threatening pathogen load but also the increase of differential metabolites in tryptophan metabolism, pyrimidine metabolism, and glycerophospholipid metabolism. Furthermore, the regulation of differential metabolites such as N-Acetylserotonin positively correlated with beneficial Rhodobacter could be a potential protection strategy for Shewanella infection. To the best of our knowledge, this is the first study to illustrate the protective effect and mechanism of R. sphaeroides supplementation to protect E. sinensis against S. putrefaciens infection.
Collapse
Affiliation(s)
- Haipeng Cao
- National Pathogen Collection Center for Aquatic Animals, Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai 201306, China.
| | - Xurui Zheng
- National Pathogen Collection Center for Aquatic Animals, Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai 201306, China
| | - Chenhao Teng
- National Pathogen Collection Center for Aquatic Animals, Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai 201306, China
| | - La Xu
- Marine Science Research Institute of Shandong Province (National Oceanographic Center), Qingdao, Shandong 266104, China
| | - Youhong Wang
- Marine Science Research Institute of Shandong Province (National Oceanographic Center), Qingdao, Shandong 266104, China
| | - Chunlei Gai
- Marine Science Research Institute of Shandong Province (National Oceanographic Center), Qingdao, Shandong 266104, China.
| | - Haibin Ye
- Marine Science Research Institute of Shandong Province (National Oceanographic Center), Qingdao, Shandong 266104, China.
| |
Collapse
|
4
|
Wang XY, Yan J, Xie J. Coculture of Acinetobacter johnsonii and Shewanella putrefaciens Contributes to the ABC Transporter that Impacts Cold Adaption in the Aquatic Food Storage Environment. J Agric Food Chem 2024. [PMID: 38647030 DOI: 10.1021/acs.jafc.4c00885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Acinetobacter johnsonii and Shewanella putrefaciens were identified as specific spoilage organisms in aquatic food. The interactions among specific spoilage organisms under cold stress have a significant impact on the assembly of microbial communities, which play crucial roles in the spoilage and cold adaptation processes. The limited understanding of A. johnsonii and S. putrefaciens interactions in the cold adaptation mechanism hinders the elucidation of their roles in protein and metabolism levels. 4D quantitative proteomic analysis showed that the coculture of A. johnsonii and S. putrefaciens responds to low temperatures through ABC transporter proteins, resulting in phospholipid transport and inner membrane components. SapA and FtsX proteins were significantly upregulated, while LolC, LolD, LolE, PotD, PotA, PotB, and PotC proteins were significantly downregulated. Metabolome assays revealed that metabolites of glutathione and spermidine/putrescin were significantly upregulated, while metabolites of arginine/lysine/ornithine were significantly downregulated and involved in the ABC transporter metabolism. The results of ultramicroscopic analyses showed that the coculture of A. johnsonii and S. putrefaciens surface combined with the presence of the leakage of intracellular contents, suggesting that the bacteria were severely damaged and wrinkled to absorb metabolic nutrients and adapt to cold temperatures.
Collapse
Affiliation(s)
- Xin-Yun Wang
- International Peace Maternity & Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200300, China
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing & Preservation, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai Ocean University, Shanghai 201306, China
| | - Jun Yan
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing & Preservation, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai Ocean University, Shanghai 201306, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering Shanghai Ocean University, Shanghai 201306, China
| | - Jing Xie
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing & Preservation, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai Ocean University, Shanghai 201306, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering Shanghai Ocean University, Shanghai 201306, China
| |
Collapse
|
5
|
Wang X, Shi Z, Wang Z, Wu X. Electromagnetic Field Drives the Bioelectrocatalysis of γ-Fe 2O 3-Coated Shewanella putrefaciens CN32 to Boost Extracellular Electron Transfer. Materials (Basel) 2024; 17:1501. [PMID: 38612017 PMCID: PMC11012369 DOI: 10.3390/ma17071501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 03/22/2024] [Accepted: 03/23/2024] [Indexed: 04/14/2024]
Abstract
The microbial hybrid system modified by magnetic nanomaterials can enhance the interfacial electron transfer and energy conversion under the stimulation of a magnetic field. However, the bioelectrocatalytic performance of a hybrid system still needs to be improved, and the mechanism of magnetic field-induced bioelectrocatalytic enhancements is still unclear. In this work, γ-Fe2O3 magnetic nanoparticles were coated on a Shewanella putrefaciens CN32 cell surface and followed by placing in an electromagnetic field. The results showed that the electromagnetic field can greatly boost the extracellular electron transfer, and the oxidation peak current of CN32@γ-Fe2O3 increased to 2.24 times under an electromagnetic field. The enhancement mechanism is mainly due to the fact that the surface modified microorganism provides an elevated contact area for the high microbial catalytic activity of the outer cell membrane's cytochrome, while the magnetic nanoparticles provide a networked interface between the cytoplasm and the outer membrane for boosting the fast multidimensional electron transport path in the magnetic field. This work sheds fresh scientific light on the rational design of magnetic-field-coupled electroactive microorganisms and the fundamentals of an optimal interfacial structure for a fast electron transfer process toward an efficient bioenergy conversion.
Collapse
Affiliation(s)
| | - Zhuanzhuan Shi
- Institute of Materials Science and Devices, School of Materials Science and Engineering, Suzhou University of Science and Technology, Suzhou 215011, China; (X.W.); (Z.W.)
| | | | - Xiaoshuai Wu
- Institute of Materials Science and Devices, School of Materials Science and Engineering, Suzhou University of Science and Technology, Suzhou 215011, China; (X.W.); (Z.W.)
| |
Collapse
|
6
|
Lu X, Zhang YY, Cheng W, Liu Y, Li Q, Li X, Dong F, Li J, Nie X. Chelating Effect of Siderophore Desferrioxamine-B on Uranyl Biomineralization Mediated by Shewanella putrefaciens. Environ Sci Technol 2024; 58:3974-3984. [PMID: 38306233 DOI: 10.1021/acs.est.3c05753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2024]
Abstract
In contaminated water and soil, little is known about the role and mechanism of the biometabolic molecule siderophore desferrioxamine-B (DFO) in the biogeochemical cycle of uranium due to complicated coordination and reaction networks. Here, a joint experimental and quantum chemical investigation is carried out to probe the biomineralization of uranyl (UO22+, referred to as U(VI) hereafter) induced by Shewanella putrefaciens (abbreviated as S. putrefaciens) in the presence of DFO and Fe3+ ion. The results show that the production of mineralized solids {hydrogen-uranium mica [H2(UO2)2(PO4)2·8H2O]} via S. putrefaciens binding with UO22+ is inhibited by DFO, which can both chelate preferentially UO22+ to form a U(VI)-DFO complex in solution and seize it from U(VI)-biominerals upon solvation. However, with Fe3+ ion introduced, the strong specificity of DFO binding with Fe3+ causes re-emergence of biomineralization of UO22+ {bassetite [Fe(UO2)2(PO4)2·8(H2O)]} by S. putrefaciens, owing to competitive complexation between Fe3+ and UO22+ for DFO. As DFO possesses three hydroxamic functional groups, it forms hexadentate coordination with Fe3+ and UO22+ ions via these functional groups. The stability of the Fe3+-DFO complex is much higher than that of U(VI)-DFO, resulting in some DFO-released UO22+ to be remobilized by S. putrefaciens. Our finding not only adds to the understanding of the fate of toxic U(VI)-containing substances in the environment and biogeochemical cycles in the future but also suggests the promising potential of utilizing functionalized DFO ligands for uranium processing.
Collapse
Affiliation(s)
- Xiaojing Lu
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang621000, China
- School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China
| | - Yang-Yang Zhang
- Department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Wencai Cheng
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang621000, China
| | - Yingzhangyang Liu
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang621000, China
| | - Qingrong Li
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang621000, China
| | - Xiaoan Li
- Mianyang Central Hospital, NHC Key Laboratory of Nuclear Technology Medical Transformation, Mianyang 621000, China
| | - Faqin Dong
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang621000, China
- Key Laboratory of Solid Waste Treatment and Resource Recycle of Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, China
| | - Jun Li
- Department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
- Department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education, Tsinghua University, Beijing 100084, China
| | - Xiaoqin Nie
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang621000, China
- Key Laboratory of Solid Waste Treatment and Resource Recycle of Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, China
| |
Collapse
|
7
|
Tenea GN, Reyes P. Bacterial community changes in strawberry fruits ( Fragaria × ananassa variety "Monterey") from farm field to retail market stands, an indicator of postharvest contamination. Front Microbiol 2024; 15:1348316. [PMID: 38435684 PMCID: PMC10904649 DOI: 10.3389/fmicb.2024.1348316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Accepted: 01/29/2024] [Indexed: 03/05/2024] Open
Abstract
Background Strawberry (Fragaria × ananassa) fruits are vulnerable to bacterial contamination; some species are pathogenic and can affect human health. Comprehending the bacterial composition and diversity at different ripe stages is a key determinant of the fruit health, productivity, and quality. Methodology An amplicon metagenomic approach on the 16S rRNA region was used to identify the bacterial diversity in exocarp of fruits collected from a farm field at two ripe stages: breaking (white, phase two) and ripe (red, phase four) and purchased from different retail market stands at ripe (red, phase four, ready-to-eat) stage. Besides, the fruit quality was assessed. Results Strawberries carries a high microorganisms diversity, with Pseudomonaceae, Yearsiniaceae, and Hafniaceae being the most abundant families across the samples. Among the groups, Pseudomonaceae and Clostridiaceae were the most abundant families at breaking (phase two) and ripe (phase four), whereas Yearsiniaceae, Hafniaceae, Aeromonadaceae, and Streptococcaceae were the most abundant families in the market group. Although samples from group four-field and market were at the same ripe stage, the bacterial species composition was divergent. Serratia spp. were prevalent (above 60%) in samples collected from the market group, and Pseudomonas (above 70%) species were mostly found in the samples collected from the field settings regardless of the phase. Besides, Escherichia coli and Salmonella enterica were detected in the ready-to-eat samples from both the field and the market, while Enterococcus gallinarum was detected in the samples that originated from the market. Interestingly, Shewanella putrefaciens and Shewanella profunda, two human opportunistic pathogens, were detected in the fruits from the market only. According to alpha and beta diversity analyses, strawberry fruits displayed significant differences (P < 0.05) in bacterial communities within the ripe group, with the samples from the market showing the most bacterial diversity. Although we do not directly correlate the quality attributes with bacterial diversity, the results indicated a clear separation between groups according with their ripe stage and origin. Conclusion This study provides a comprehensive framework of the bacterial diversity throughout the transition from unripe to ripe strawberries which may aid in the development of preventative measures to manage the postharvest contamination.
Collapse
Affiliation(s)
- Gabriela N. Tenea
- Biofood and Nutraceutics Research and Development Group, Faculty of Engineering in Agricultural and Environmental Sciences, Universidad Técnica del Norte, Ibarra, Ecuador
| | | |
Collapse
|
8
|
Cai Y, Chen X, Qi H, Bu F, Shaaban M, Peng QA. Genome analysis of Shewanella putrefaciens 4H revealing the potential mechanisms for the chromium remediation. BMC Genomics 2024; 25:136. [PMID: 38308218 PMCID: PMC10837877 DOI: 10.1186/s12864-024-10031-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 01/19/2024] [Indexed: 02/04/2024] Open
Abstract
Microbial remediation of heavy metal polluted environment is ecofriendly and cost effective. Therefore, in the present study, Shewanella putrefaciens stain 4H was previously isolated by our group from the activated sludge of secondary sedimentation tank in a dyeing wastewater treatment plant. The bacterium was able to reduce chromate effectively. The strains showed significant ability to reduce Cr(VI) in the pH range of 8.0 to 10.0 (optimum pH 9.0) and 25-42 ℃ (optimum 30 ℃) and were able to reduce 300 mg/L of Cr(VI) in 72 h under parthenogenetic anaerobic conditions. In this paper, the complete genome sequence was obtained by Nanopore sequencing technology and analyzed chromium metabolism-related genes by comparative genomics The genomic sequence of S. putrefaciens 4H has a length of 4,631,110 bp with a G + C content of 44.66% and contains 4015 protein-coding genes and 3223, 2414, 2343 genes were correspondingly annotated into the COG, KEGG, and GO databases. The qRT-PCR analysis showed that the expression of chrA, mtrC, and undA genes was up-regulated under Cr(VI) stress. This study explores the Chromium Metabolism-Related Genes of S. putrefaciens 4H and will help to deepen our understanding of the mechanisms of Cr(VI) tolerance and reduction in this strain, thus contributing to the better application of S. putrefaciens 4H in the field of remediation of chromium-contaminated environments.
Collapse
Affiliation(s)
- Yajun Cai
- College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China
- Clean Production of Textile Printing and Dyeing Engineering Research Center of Ministry of Education, Wuhan, 430200, China
| | - Xu Chen
- College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China
| | - Hanghang Qi
- College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China
| | - Fantong Bu
- College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China
| | - Muhammad Shaaban
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
| | - Qi-An Peng
- College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China.
- Clean Production of Textile Printing and Dyeing Engineering Research Center of Ministry of Education, Wuhan, 430200, China.
| |
Collapse
|
9
|
Xie J, Li D, Wang Y. The bioreduction of U(VI) and Pu(IV): Experimental and thermodynamic studies. J Environ Radioact 2024; 272:107356. [PMID: 38113757 DOI: 10.1016/j.jenvrad.2023.107356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/16/2023] [Accepted: 12/09/2023] [Indexed: 12/21/2023]
Abstract
The experimental and thermodynamic bioreduction of U(VI)aq and Pu(IV)am was studied in order to more accurately predict their transport velocities in groundwater and assess the contamination risks to the associated environments. The results obtained in this study emphasize the impact of carbonate-calcium and humic acids at 7.1 and anoxic solutions on the rate and extent of U(VI)aq and Pu(IV)am bioreduction by Shewanella putrefaciens. We found that the bioreduction rate of U(VI)aq became slow in the presence of NaHCO3/CaCl2. The more negative standard redox potentials of the ternary complexes of U(VI)-Ca2+-CO32- accounted for the decreased rate of bioreduction, e.g., [Formula: see text] = -0.6797 V ≪ [Formula: see text] = 0.3862 V. The bioreduction of Pu(IV)am seemed feasible, while humic acids accepted the adequate extracellular electrons secreted by S. putrefaciens, and the redox potential of Eh(HAox/HAred) was lower than Eh(PuO2(am)/Pu3+), e.g., Eh(HAox/HAred) ≦ Eh(PuO2(am)/Pu3+) if humic acids accepted ≧ 7.952 × 10-7 mol of electrons. The standard redox potentials, Eho(PuO2(am)/Pu3+) = 0.9295 V ≫ [Formula: see text] = -0.6797 V, cannot explain the reduction extent of Pu(IV)am (8.9%), which is notably smaller than that of U(VI)aq (74.9%). In fact, the redox potential of Pu(IV)am was distinctly negative under the experimental conditions of trace-level Pu(IV)am (∼2.8 × 10-9 mol/L Pu(IV) if Pu(IV)am was completely dissolved), e.g., Eh(PuO2(am)/Pu3+) = -0.1590 V (α(Pu3+) = 10-10 mol/L, pH = 7.1). Therefore, the chemical factor of Pu3+ activity, leading to a rapid drop in Eh(PuO2(am)/Pu3+) at trace-level Pu(IV)am, was responsible for the relatively small reduction extent of Pu(IV)am.
Collapse
Affiliation(s)
- Jinchuan Xie
- Institute of Military-Civilian Integration Technology, Northwest University of Political Science and Law, Xi'an, Shaanxi, 710122, China.
| | - Dongyan Li
- Institute of Military-Civilian Integration Technology, Northwest University of Political Science and Law, Xi'an, Shaanxi, 710122, China
| | - Yu Wang
- Northwest Institute of Nuclear Technology, P.O. Box 69-14, Xi'an, Shaanxi, 710024, China
| |
Collapse
|
10
|
Kumar A, Pandit S, Sharma K, Mathuriya AS, Prasad R. Evaluation of bamboo derived biochar as anode catalyst in microbial fuel cell for xylan degradation utilizing microbial co-culture. Bioresour Technol 2023; 390:129857. [PMID: 37852505 DOI: 10.1016/j.biortech.2023.129857] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/04/2023] [Accepted: 10/07/2023] [Indexed: 10/20/2023]
Abstract
This study aimed to examine the microbial degradation of xylan through Bacillus sp. isolated from wastewater. Co-culture of Bacillus licheniformis strain and MTCC-8104 strain of Shewanella putrefaciens were employed in a microbial fuel cell (MFC) to facilitate energy production simultaneous xylan degradation under optimum conditions. Electrochemical properties of MFC and degradation analysis were used to validate xylan degradation throughout various experimental parameters. Degradation of the optimal xylan concentration using co-culture, resulting in a power density of 7.8 W/m3, the anode surface was modified with bamboo-derived biochar in order to increase power density under the same operational condition. Under optimum circumstances, increasing the anode's surface area boosted electron transport and electro-active biofilm growth, resulting in a higher power density of 12.9 W/m3. Co-culture of hydrolyzing and electro-active bacteria was found beneficial for xylan degradation and anode modifications enhance power output while microbial degradation.
Collapse
Affiliation(s)
- Ankit Kumar
- Department of Life Sciences, School of Basic Science and Research, Sharda University, Greater Noida 201310, India
| | - Soumya Pandit
- Department of Life Sciences, School of Basic Science and Research, Sharda University, Greater Noida 201310, India
| | - Kalpana Sharma
- Department of Life Sciences, School of Basic Science and Research, Sharda University, Greater Noida 201310, India
| | - Abhilasha Singh Mathuriya
- Ministry of Environment, Forest and Climate Change, Indira Paryavaran Bhawan, Jor Bagh, New Delhi 110003, India
| | - Ram Prasad
- Department of Botany, Mahatma Gandhi Central University, Motihari 845401, Bihar, India.
| |
Collapse
|
11
|
Peng J, Feng F, Zhang G, Zou L. Transcriptome Analysis Reveals the Inhibitory Effect of Cu 2+ on Polyferric Sulfate Floc Reduction by Shewanella putrefaciens CN32. Appl Biochem Biotechnol 2023:10.1007/s12010-023-04787-1. [PMID: 37979084 DOI: 10.1007/s12010-023-04787-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2023] [Indexed: 11/19/2023]
Abstract
Polyferric sulfate (PFS), an economical coagulant widely used for removing heavy metal contaminants from water, is susceptible to reduction and transformation by iron-reducing bacteria prevalent in sediments. However, the effect of heavy metal ions adsorbed in PFS flocs on this biological process remains unclear. According to our results, compared with other heavy metal cations (e.g., Cu2+, Cd2+, Zn2+, Ni2+, Pb2+, and Co2+), Cu2+ had a stronger inhibitory effect on PFS floc reduction by Shewanella putrefaciens CN32, a typical dissimilatory iron-reducing bacterium. The presence of Cu2+ remarkably influenced the global transcription of CN32, resulting in 782 upregulated genes and 713 downregulated genes that are mainly annotated in energy production, amino acid metabolism, protein biosynthesis, and oxidation‒reduction processes. The anaerobic TCA cycle for energy (electron) production was significantly activated in the presence of Cu2+, while the transcription of many genes related to the extracellular electron transfer pathway was downregulated, which is responsible for the decreased Fe3+ reduction. Moreover, the pathways of assimilatory sulfate reduction and subsequent cysteine biosynthesis were significantly enriched, which is hypothesized to result in the consumption of abundant energy produced from the enhanced anaerobic TCA cycle, revealing a strategy to address the oxidative stress caused by Cu2+. This work elucidates the unusual suppressive effects of Cu2+ on the microbial reduction of PFS flocs, which reveals the high resistance of PFS flocs to microbial destruction when used to treat Cu2+ pollution in water, thus demonstrating their tremendous practical prospects.
Collapse
Affiliation(s)
- Jiaxin Peng
- Nanchang Key Laboratory of Microbial Resources Exploitation & Utilization from Poyang Lake Wetland, College of Life Sciences, Jiangxi Normal University, Nanchang, 330022, China
| | - Fei Feng
- Nanchang Key Laboratory of Microbial Resources Exploitation & Utilization from Poyang Lake Wetland, College of Life Sciences, Jiangxi Normal University, Nanchang, 330022, China
| | - Gang Zhang
- Nanchang Key Laboratory of Microbial Resources Exploitation & Utilization from Poyang Lake Wetland, College of Life Sciences, Jiangxi Normal University, Nanchang, 330022, China
| | - Long Zou
- Nanchang Key Laboratory of Microbial Resources Exploitation & Utilization from Poyang Lake Wetland, College of Life Sciences, Jiangxi Normal University, Nanchang, 330022, China.
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, 430062, China.
| |
Collapse
|
12
|
Dabadé DS, Yessoufou N, Adido L, Azokpota P, Hounhouigan DJ. Quality changes, potential spoilage organisms, and shelf-life prediction of brackish river prawn (Macrobrachium macrobrachion) at different storage temperatures. Int J Food Microbiol 2023; 405:110344. [PMID: 37544194 DOI: 10.1016/j.ijfoodmicro.2023.110344] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/24/2023] [Accepted: 07/27/2023] [Indexed: 08/08/2023]
Abstract
The brackish river prawn (Macrobrachium macrobrachion) is a species of commercial importance in West Africa. However, like other fishery products, it is prone to deterioration due mainly to microbial activities. The present study aimed at evaluating the spoilage characteristics of M. macrobrachion and predicting the growth of the main spoilage bacteria as well as the shelf-life of the product as a function of storage temperature. Freshly caught brackish river prawn samples from Lake Aheme were aerobically stored at 0, 7, 15, and 28 °C and, at pre-determined times during storage, they were taken for microbiological, chemical, and sensory analysis. At sensory rejection times, the spoilage potential of 185 isolates from specific groups of organisms enumerated was assessed in prawn of which the endogenous microbiota was heat inactivated. Isolates capable of producing strong off-odor were identified using 16S rRNA sequencing. Models predicting the maximum growth rate of Pseudomonas spp. and H2S-producing bacteria in the brackish river prawn as well as the shelf-life of the product were developed. These models were validated using an independent experiment during which prawn was stored at 0, 4, 10, and 25 °C. Results showed that Pseudomonas spp. at 0 °C, Pseudomonas spp. and H2S-producing bacteria at 7 °C, and H2S-producing bacteria at 15 °C and 28 °C were the dominant groups of microorganisms during storage. As expected, total volatile basic nitrogen, trimethylamine, and pH with initial values of 21.2 ± 3.0 mg-N/100 g, 4.1 ± 0.8 mg-N/100 g, and 7.46 ± 0.15 increased during storage reaching approximately 35 mg-N/100 g, 10 mg/ 100 g and 8, respectively at sensory rejection times which were 7 h at 28 °C, 1.2 d at 15 °C, 4.6 d at 7 °C, and 11.7 d at 0 °C. The main spoilage organisms were Citrobacter braakii at 28 °C, Citrobacter braakii, Pseudomonas kurunegalensis, and Shewanella bicestrii at 15 °C, Shewanella putrefaciens, Shewanella baltica, and Pseudomonas bubulae at 7 °C, and Pseudomonas versuta at 0 °C. The validation of the developed models showed an adequate agreement between the predicted and observed values. This study highlights the specific spoilage characteristics of the brackish river prawn and reveals that Gram-negative rod bacteria are the main spoilage organisms even at high storage temperatures, contrary to many earlier reports on the spoilage of tropical fishery products.
Collapse
Affiliation(s)
- D Sylvain Dabadé
- Laboratory of Food Science and Technology, University of Abomey-Calavi, 03 B.P. 2819 Jericho-Cotonou, Benin.
| | - Nadiath Yessoufou
- Laboratory of Food Science and Technology, University of Abomey-Calavi, 03 B.P. 2819 Jericho-Cotonou, Benin
| | - Lionel Adido
- Laboratory of Food Science and Technology, University of Abomey-Calavi, 03 B.P. 2819 Jericho-Cotonou, Benin
| | - Paulin Azokpota
- Laboratory of Food Science and Technology, University of Abomey-Calavi, 03 B.P. 2819 Jericho-Cotonou, Benin
| | - D Joseph Hounhouigan
- Laboratory of Food Science and Technology, University of Abomey-Calavi, 03 B.P. 2819 Jericho-Cotonou, Benin
| |
Collapse
|
13
|
Xie Y, Zhang C, Mei J, Xie J. Antimicrobial Effect of Ocimum gratissimum L. Essential Oil on Shewanella putrefaciens: Insights Based on the Cell Membrane and External Structure. Int J Mol Sci 2023; 24:11066. [PMID: 37446243 DOI: 10.3390/ijms241311066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/28/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
The main objective of this study was to assess the in vitro antibacterial effectiveness of Ocimum gratissimum L. essential oil (OGEO) against Shewanella putrefaciens. The minimum inhibitory concentration and minimum bactericidal concentration of OGEO acting on S. putrefaciens were both 0.1% and OGEO could inhibit the growth of S. putrefaciens in a dose-dependent manner. The restraint of the biofilm growth of S. putrefaciens was found in the crystal violet attachment assay and confocal laser scanning microscopy. The disruption of cell membranes and exudation of contents in S. putrefaciens with OGEO treatment were observed by scanning electron microscopy, hemolysis and ATPase activity. The results demonstrated that OGEO had a positive inhibitory effect on the growth of S. putrefaciens, which primarily developed its antibacterial function against S. putrefaciens by disrupting the formation of biofilms and cell membranes. This study could provide a new method of inhibiting the spoilage of food in which the dominant spoilage bacteria are S. putrefaciens.
Collapse
Affiliation(s)
- Yao Xie
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Chi Zhang
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Jun Mei
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China
- Key Laboratory of Aquatic Products High Quality Utilization, Storage and Transportation (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Shanghai 201306, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai 201306, China
| | - Jing Xie
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China
- Key Laboratory of Aquatic Products High Quality Utilization, Storage and Transportation (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Shanghai 201306, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai 201306, China
| |
Collapse
|
14
|
Wang XY, Yan J, Xie J. Applications of Genomics, Metabolomics, Fourier Transform Infrared in the Evaluation of Spoilage Targets of Shewanella putrefaciens from Spoiled Bigeye Tuna. J Agric Food Chem 2023. [PMID: 37306251 DOI: 10.1021/acs.jafc.3c02113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Shewanella putrefaciens is a typical spoiler that is commonly found in seafood and has high spoilage potential. However, the spoilage mechanism against Shewanella putrefaciens at the gene and metabolism levels has not been well elucidated. This work determined the spoilage targets on Shewanella putrefaciens XY07 from spoiled bigeye tuna by genome sequencing, metabolomics, and Fourier transform infrared (FTIR) analysis. Shewanella putrefaciens XY07 contained some genes on spoilage regulating of cys genes, his genes, spe genes and rpoS gene involved in sulfur metabolism, histidine metabolism, arginine and proline degradation, and biofilm formation at the genome level, respectively. Some spoilage genes like speC, cysM, trxB genes were identified. In addition, ABC transporters, arginine and proline metabolism; beta-alanine metabolism; glycine, serine, and threonine metabolism; histidine metabolism; sulfur metabolism; and lipid metabolism were identified as important pathways related to aquatic food during spoilage, which indicated the functions of amino acid degradation in S. putrefaciens XY 07 by metabolomics analysis. The metabolites of l-ornithine, 5-aminopentanoate, and 4-aminobutyraldehyde could be further metabolized to spermidine and spermine, producing a spoilage odor, and were involved in arginine and proline metabolism serving as key spoilage regulating metabolisms. Therefore, Shewanella putrefaciens XY07 was applied to genomics, metabolomics analysis, and FTIR to provide comprehensive insight into the investigation of spoilage targets.
Collapse
Affiliation(s)
- Xin-Yun Wang
- College of Food Science & Technology, Shanghai Ocean University, Shanghai, 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing & Preservation, Shanghai Ocean University, Shanghai, 201306, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai Ocean University, Shanghai, 201306, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai, 201306, China
| | - Jun Yan
- College of Food Science & Technology, Shanghai Ocean University, Shanghai, 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing & Preservation, Shanghai Ocean University, Shanghai, 201306, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai Ocean University, Shanghai, 201306, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai, 201306, China
| | - Jing Xie
- College of Food Science & Technology, Shanghai Ocean University, Shanghai, 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing & Preservation, Shanghai Ocean University, Shanghai, 201306, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai Ocean University, Shanghai, 201306, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai, 201306, China
| |
Collapse
|
15
|
Hu J, Huang W, Wang Y, Jin J, Li Y, Chen J, Zheng Y, Deng S. Atmospheric cold plasma: A potential technology to control Shewanella putrefaciens in stored shrimp. Int J Food Microbiol 2023; 390:110127. [PMID: 36806858 DOI: 10.1016/j.ijfoodmicro.2023.110127] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 02/04/2023] [Accepted: 02/07/2023] [Indexed: 02/12/2023]
Abstract
This work aimed to investigate the inactivation mechanism of atmospheric cold plasma (ACP) against Shewanella putrefaciens both in PBS and sterile shrimp juice (SSJ). Reductions in cell density, cell viability, and biofilm formation activity were observed after ACP treatment. ACP cyclical treatment (1 min, 5 times) was more efficient than a one-time treatment (5 min, 1 time). After ACP cyclical treatment, the cell counts and cell viability of S. putrefaciens in PBS were decreased by 3.41 log CFU/mL and 85.30 %, respectively. As for SSJ group, the antibacterial efficiency of ACP declined, but the antibacterial effect of ACP cyclical treatment was still stronger than that of ACP one-time treatment. The biofilm formation activity of S. putrefaciens in PBS was almost completely inhibited, while it gradually returned to normal level with the prolonged of storage time for the SSJ counterpart. The rapid decrease in AKP activity after ACP treatment indicated the damage to cell wall integrity, which was also demonstrated by TEM. In addition, cell membrane and DNA damage of the strain also occurred after ACP treatment. The ROS fluorescence intensity in PBS was higher for the one-time treatment group, while the cyclical treatment group exhibited higher and more stable ozone levels. It was also detected that the total nitric oxide concentration in bacterial suspension depended on the dose of ACP treatment time. ACP treatment (35 kV) for 5 min, especially cyclical treatment, displayed its antibacterial properties on packaged shrimp contaminated with high concentration of S. putrefaciens. ACP cyclical treatment reduced surface bacterial counts of whole shrimps by 0.52 log CFU/mL, while ACP one-time treatment only achieved a decrease of 0.18 log CFU/mL. Therefore, ACP treatment could be considered as a potential alternative to enhance microbial control in food processing.
Collapse
Affiliation(s)
- Jiajie Hu
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China
| | - Weijiao Huang
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China
| | - Yihong Wang
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China
| | - Jing Jin
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China
| | - Yuwei Li
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China
| | - Jing Chen
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China; Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province, 316022 Zhoushan, China.
| | - Yan Zheng
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China; Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province, 316022 Zhoushan, China
| | - Shanggui Deng
- School of Food and Pharmacy, Zhejiang Ocean University, 316022 Zhoushan, China; Key Laboratory of Health Risk Factors for Seafood of Zhejiang Province, 316022 Zhoushan, China
| |
Collapse
|
16
|
Ding J, Dwibedi V, Huang H, Ge Y, Li Y, Li Q, Sun T. Preparation and antibacterial mechanism of cinnamaldehyde/tea polyphenol/polylactic acid coaxial nanofiber films with zinc oxide sol to Shewanella putrefaciens. Int J Biol Macromol 2023; 237:123932. [PMID: 36894058 DOI: 10.1016/j.ijbiomac.2023.123932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 02/19/2023] [Accepted: 03/01/2023] [Indexed: 03/09/2023]
Abstract
In this study, the coaxial nanofiber films were prepared by coaxial electrospinning technique with cinnamaldehyde (CMA) and tea polyphenol (TP) as core material and polylactic acid (PLA) as shell material, and to obtain food packaging materials with great physicochemical and antibacterial properties, zinc oxide (ZnO) sol were added into PLA, and ZnO/CMA/TP-PLA coaxial nanofiber films were prepared. Meanwhile, the microstructure and physicochemical properties were determined, and the antibacterial properties and mechanism were investigated with Shewanella putrefaciens (S. putrefaciens) as target. The results show that the ZnO sol makes the physicochemical properties and antibacterial properties of the coaxial nanofiber films improve. Among them, the 1.0 % ZnO/CMA/TP-PLA coaxial nanofibers have smooth and continuous uniform surfaces, and their encapsulation effect on CMA/TP and antibacterial properties are the optimal. The synergistic action of CMA/TP and ZnO sol cause severe depression and folding of the cell membrane of S. putrefaciens, makes cell membrane permeability increase and of intracellular materials spillage, interference the bacteriophage protein expression, and makes macromolecular protein degraded. In this study, the introduction of oxide sols into polymeric shell materials by in-situ synthesis technique can provide theoretical support and methodological guidance for the application of electrospinning technology in the field of food packaging.
Collapse
Affiliation(s)
- Jie Ding
- College of Food Science and Engineering, Bohai University, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Key Laboratory of Food Safety of Liaoning Province, Jinzhou 121013, China; Shanghai Syntheall Pharmaceutical Co., Ltd., 201200, China
| | - Vagish Dwibedi
- University Institute of Biotechnology, Chandigarh University Mohali, Punjab 140413, India
| | - Haitao Huang
- College of Food Science and Engineering, Bohai University, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Key Laboratory of Food Safety of Liaoning Province, Jinzhou 121013, China
| | - Yonghong Ge
- College of Food Science and Engineering, Bohai University, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Key Laboratory of Food Safety of Liaoning Province, Jinzhou 121013, China
| | - Yingchang Li
- College of Food Science and Engineering, Bohai University, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Key Laboratory of Food Safety of Liaoning Province, Jinzhou 121013, China.
| | - Qiuying Li
- College of Food Science and Engineering, Bohai University, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Key Laboratory of Food Safety of Liaoning Province, Jinzhou 121013, China
| | - Tong Sun
- College of Food Science and Engineering, Bohai University, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Key Laboratory of Food Safety of Liaoning Province, Jinzhou 121013, China.
| |
Collapse
|
17
|
Müller S, von Bonin S, Schneider R, Krüger M, Quick S, Schröttner P. Shewanella putrefaciens, a rare human pathogen: A review from a clinical perspective. Front Cell Infect Microbiol 2023; 12:1033639. [PMID: 36817694 PMCID: PMC9933709 DOI: 10.3389/fcimb.2022.1033639] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 10/04/2022] [Indexed: 02/05/2023] Open
Abstract
Shewanella putrefaciens is a gramnegative, facultatively anaerobic, rod shaped bacterium. It belongs to the class of the Gammaproteobacteria and was first described in 1931. S. putrefaciens is part of the marine microflora and especially present in moderate and warm climates. The bacterium is a rare oppurtonistic human pathogen associated mainly with intra-abdominal as well as skin and soft tissue infections. However, it has also been reported in association with more severe diseases such as pneumonia, intracerebral and ocular infections and endocarditis. In these cases the clinical courses are often associated with underlying, predisposing diseases and risk factors. For successful treatment of S. putrefaciens, a combination of appropriate local therapy, e.g. surgical treatment or drainage, and antibiotic therapy should be performed. Since multiple resistances to antibiotics are described, the results of the antimicrobial susceptibility testing must be considered for effective therapy as well. Furthermore, a main challenge in clinical practice is the accurate microbiological identification, and especially the correct differentiation between S. putrefaciens and S. algae. Under certain circumstances, Shewanella-infections can have severe, sometimes even fatal consequences. Therefore, we decided to present the current state of knowledge as well as further aspects with regard to future diagnostics, therapy and research.
Collapse
Affiliation(s)
- Stephanie Müller
- Department of Medicine I, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany,*Correspondence: Stephanie Müller,
| | - Simone von Bonin
- Department of Medicine I, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Ralph Schneider
- Department of Medicine I, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Martin Krüger
- Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Susanne Quick
- Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Percy Schröttner
- Institute for Medical Microbiology and Virology, University Hospital Carl Gustav Carus, Dresden, Germany
| |
Collapse
|
18
|
Domínguez-Maqueda M, Pérez-Gómez O, Grande-Pérez A, Esteve C, Seoane P, Tapia-Paniagua ST, Balebona MC, Moriñigo MA. Pathogenic strains of Shewanella putrefaciens contain plasmids that are absent in the probiotic strain Pdp11. PeerJ 2022; 10:e14248. [PMID: 36312754 PMCID: PMC9610664 DOI: 10.7717/peerj.14248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 09/26/2022] [Indexed: 01/24/2023] Open
Abstract
Shewanella putrefaciens Pdp11 is a strain described as a probiotic for use in aquaculture. However, S. putrefaciens includes strains reported to be pathogenic or saprophytic to fish. Although the probiotic trait has been related to the presence of a group of genes in its genome, the existence of plasmids that could determine the probiotic or pathogenic character of this bacterium is unknown. In the present work, we searched for plasmids in several strains of S. putrefaciens that differ in their pathogenic and probiotic character. Under the different conditions tested, plasmids were only found in two of the five pathogenic strains, but not in the probiotic strain nor in the two saprophytic strains tested. Using a workflow integrating Sanger and Illumina reads, the complete consensus sequences of the plasmids were obtained. Plasmids differed in one ORF and encoded a putative replication initiator protein of the repB family, as well as proteins related to plasmid stability and a toxin-antitoxin system. Phylogenetic analysis showed some similarity to functional repB proteins of other Shewanella species. The implication of these plasmids in the probiotic or pathogenic nature of S. putrefaciens is discussed.
Collapse
Affiliation(s)
| | | | - Ana Grande-Pérez
- Área de Genética, Universidad de Málaga, Málaga, Spain,Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”-Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Universidad de Málaga, Málaga, Spain
| | - Consuelo Esteve
- Departmento de Microbiología y Ecología, Universidad de Valencia, Valencia, Spain
| | - Pedro Seoane
- Centro de Investigación Biomédica en Red de Enfermedades Raras, CIBERER, Madrid, Spain,Departmento de Biología Molecular y Bioquímica, Universidad de Málaga, Málaga, Spain
| | | | | | | |
Collapse
|
19
|
Mateos G, Bonilla AM, de Francisco de Polanco S, Martínez JM, Escudero C, Rodríguez N, Sánchez-Andrea I, Amils R. Shewanella sp. T2.3D-1.1 a Novel Microorganism Sustaining the Iron Cycle in the Deep Subsurface of the Iberian Pyrite Belt. Microorganisms 2022; 10:1585. [PMID: 36014003 DOI: 10.3390/microorganisms10081585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 07/29/2022] [Accepted: 08/03/2022] [Indexed: 11/16/2022] Open
Abstract
The Iberian Pyrite Belt (IPB) is one of the largest deposits of sulphidic minerals on Earth. Río Tinto raises from its core, presenting low a pH and high metal concentration. Several drilling cores were extracted from the IPB’s subsurface, and strain T2.3D-1.1 was isolated from a core at 121.8 m depth. We aimed to characterize this subterranean microorganism, revealing its phylogenomic affiliation (Average Nucleotide Identity, digital DNA-DNA Hybridization) and inferring its physiology through genome annotation, backed with physiological experiments to explore its relationship with the Fe biogeochemical cycle. Results determined that the isolate belongs to the Shewanella putrefaciens (with ANI 99.25 with S. putrefaciens CN-32). Its genome harbours the necessary genes, including omcA mtrCAB, to perform the Extracellular Electron Transfer (EET) and reduce acceptors such as Fe3+, napAB to reduce NO3− to NO2−, hydAB to produce H2 and genes sirA, phsABC and ttrABC to reduce SO32−, S2O32− and S4O62−, respectively. A full CRISPR-Cas 1F type system was found as well. S. putrefaciens T2.3D-1.1 can reduce Fe3+ and promote the oxidation of Fe2+ in the presence of NO3− under anaerobic conditions. Production of H2 has been observed under anaerobic conditions with lactate or pyruvate as the electron donor and fumarate as the electron acceptor. Besides Fe3+ and NO3−, the isolate also grows with Dimethyl Sulfoxide and Trimethyl N-oxide, S4O62− and S2O32− as electron acceptors. It tolerates different concentrations of heavy metals such as 7.5 mM of Pb, 5 mM of Cr and Cu and 1 mM of Cd, Co, Ni and Zn. This array of traits suggests that S. putrefaciens T2.3D-1.1 could have an important role within the Iberian Pyrite Belt subsurface participating in the iron cycle, through the dissolution of iron minerals and therefore contributing to generate the extreme conditions detected in the Río Tinto basin.
Collapse
|
20
|
Nie X, Lin Q, Dong F, Cheng W, Ding C, Wang J, Liu M, Chen G, Zhou Y, Li X, Boyanov MI, Kemner KM. Surface biomineralization of uranium onto Shewanella putrefaciens with or without extracellular polymeric substances. Ecotoxicol Environ Saf 2022; 241:113719. [PMID: 35691198 DOI: 10.1016/j.ecoenv.2022.113719] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/16/2022] [Accepted: 05/28/2022] [Indexed: 06/15/2023]
Abstract
The influence of extracellular polymeric substances (EPS) on the interaction between uranium [U(VI)] and Shewanella putrefaciens (S. putrefaciens), especially the U(VI) biomineralization process occurring on whole cells and cell components of S. putrefaciens was investigated in this study. The removal efficiency of U(VI) by S. putrefaciens was decreased by 22% after extraction of EPS. Proteins were identified as the main components of EPS by EEM analysis and were determined to play a major role in the biosorption of uranium. SEM-EDS results showed that U(VI) was distributed around the whole cell as 500-nanometer schistose structures, which consisted primarily of U and P. However, similar uranium lamellar crystal were wrapped only on the surface of EPS-free S. putrefaciens cells. FTIR and XPS analysis indicated that phosphorus- and nitrogen-containing groups played important roles in complexing U (VI). XRD and U LIII-edge EXAFS analyses demonstrated that the schistose structure consisted of hydrogen uranyl phosphate [H2(UO2)2(PO4)2•8H2O]. Our study provides new insight into the mechanisms of induced uranium crystallization by EPS and cell wall membranes of living bacterial cells under aerobic conditions.
Collapse
Affiliation(s)
- Xiaoqin Nie
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, China; Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang 621010, China; Mianyang Central Hospital, NHC Key Laboratory of Nuclear Technology Medical Transformation,Mianyang 621000, China.
| | - Qiaoya Lin
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, China; Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China
| | - Faqin Dong
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, China; Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, China
| | - Wencai Cheng
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, China
| | - Congcong Ding
- Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang 621010, China
| | - Junling Wang
- Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang 621010, China
| | - Mingxue Liu
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, China
| | - Guozheng Chen
- Mianyang Central Hospital, NHC Key Laboratory of Nuclear Technology Medical Transformation,Mianyang 621000, China
| | - Yan Zhou
- Mianyang Central Hospital, NHC Key Laboratory of Nuclear Technology Medical Transformation,Mianyang 621000, China
| | - Xiaoan Li
- Mianyang Central Hospital, NHC Key Laboratory of Nuclear Technology Medical Transformation,Mianyang 621000, China.
| | - Maxim I Boyanov
- Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA; Bulgarian Academy of Sciences, Institute of Chemical Engineering, Sofia 1113, Bulgaria
| | - Kenneth M Kemner
- Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA
| |
Collapse
|
21
|
Zhang J, Wei S, Liu Z, Tang H, Meng X, Zhu W. Release of Pb adsorbed on graphene oxide surfaces under conditions of Shewanella putrefaciens metabolism. J Environ Sci (China) 2022; 118:67-75. [PMID: 35305774 DOI: 10.1016/j.jes.2021.08.041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 08/21/2021] [Accepted: 08/22/2021] [Indexed: 06/14/2023]
Abstract
In this study, Pb(II) was used as a target heavy metal pollutant, and the metabolism of Shewanella putrefaciens (S. putrefaciens) was applied to achieve reducing conditions to study the effect of microbial reduction on lead that was preadsorbed on graphene oxide (GO) surfaces. The results showed that GO was transformed to its reduced form (r-GO) by bacteria, and this process induced the release of Pb(II) adsorbed on the GO surfaces. After 72 hr of exposure in an S. putrefaciens system, 5.76% of the total adsorbed Pb(II) was stably dispersed in solution in the form of a Pb(II)-extracellular polymer substance (EPS) complex, while another portion of Pb(II) released from GO-Pb(II) was observed as lead phosphate hydroxide (Pb10(PO4)6(OH)2) precipitates or adsorbed species on the surface of the cell. Additionally, increasing pH induced the stripping of oxidative debris (OD) and elevated the content of dispersible Pb(II) in aqueous solution under the conditions of S. putrefaciens metabolism. These research results provide valuable information regarding the migration of heavy metals adsorbed on GO under reducing conditions due to microbial metabolism.
Collapse
Affiliation(s)
- Jianfeng Zhang
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Shichang Wei
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Zhenxing Liu
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Huang Tang
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xiaoguang Meng
- Center for Environmental Systems, Stevens Institute of Technology, NJ 07030, USA
| | - Weihuang Zhu
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China
| |
Collapse
|
22
|
Li P, Mei J, Tan M, Xie J. Effect of CO 2 on the spoilage potential of Shewanella putrefaciens target to flavour compounds. Food Chem 2022; 397:133748. [PMID: 35905618 DOI: 10.1016/j.foodchem.2022.133748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 06/23/2022] [Accepted: 07/18/2022] [Indexed: 11/20/2022]
Abstract
To investigate the regulation mechanism of CO2 (0% CO2, 20% CO2, 60% CO2, and 100% CO2) on the spoilage potential of S. putrefaciens target to flavour compounds, the metabolic activity of S. putrefaciens and the changes in flavour compounds extracted from inoculated large yellow croakers were evaluated. Results showed that CO2 significantly reduced biofilm formation capacity and suppressed synthesis of intracellular adenosine triphosphate (ATP). The production of unpleasant flavour compounds, such as total volatile basic nitrogen (TVB-N), trimethylamine (TMA), inosine (HxR), hypoxanthine (Hx), histidine, lysine, histamine, putrescine, 1-octen-3-ol, hexanal and benzaldehyde, was inhibited by CO2. The hydrolysis and oxidation of lipid in CO2-treated samples were alleviated and unsaturated fatty acids (UFAs) were in a higher percentage. In summary, CO2 efficiently reduced the spoilage potential of S. putrefaciens and contributed to better flavour quality of samples during 4 °C storage. A more effective inhibition by 100% CO2 was observed.
Collapse
|
23
|
Yi Z, Xie J. Genomic Analysis of Two Representative Strains of Shewanella putrefaciens Isolated from Bigeye Tuna: Biofilm and Spoilage-Associated Behavior. Foods 2022; 11:foods11091261. [PMID: 35563985 PMCID: PMC9100107 DOI: 10.3390/foods11091261] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 04/22/2022] [Accepted: 04/26/2022] [Indexed: 01/27/2023] Open
Abstract
Shewanella putrefaciens can cause the spoilage of seafood and shorten its shelf life. In this study, both strains of S. putrefaciens (YZ08 and YZ-J) isolated from spoiled bigeye tuna were subjected to in-depth phenotypic and genotypic characterization to better understand their roles in seafood spoilage. The complete genome sequences of strains YZ08 and YZ-J were reported. Unique genes of the two S. putrefaciens strains were identified by pan-genomic analysis. In vitro experiments revealed that YZ08 and YZ-J could adapt to various environmental stresses, including cold-shock temperature, pH, NaCl, and nutrient stresses. YZ08 was better at adapting to NaCl stress, and its genome possessed more NaCl stress-related genes compared with the YZ-J strain. YZ-J was a higher biofilm and exopolysaccharide producer than YZ08 at 4 and 30 °C, while YZ08 showed greater motility and enhanced capacity for biogenic amine metabolism, trimethylamine metabolism, and sulfur metabolism compared with YZ-J at both temperatures. That YZ08 produced low biofilm and exopolysaccharide contents and displayed high motility may be associated with the presence of more a greater number of genes encoding chemotaxis-related proteins (cheX) and low expression of the bpfA operon. This study provided novel molecular targets for the development of new antiseptic antisepsis strategies.
Collapse
Affiliation(s)
- Zhengkai Yi
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China;
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai 201306, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai 201306, China
| | - Jing Xie
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China;
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai 201306, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing & Preservation, Shanghai 201306, China
- Correspondence: ; Tel.: +86-02161900391
| |
Collapse
|
24
|
Shyam Mohan AH, Rao SN, D S, Rajeswari N. In silico structural, phylogenetic and drug target analysis of putrescine monooxygenase from Shewanella putrefaciens-95. J Genet Eng Biotechnol 2022; 20:57. [PMID: 35412199 PMCID: PMC9005580 DOI: 10.1186/s43141-022-00338-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 03/22/2022] [Indexed: 11/10/2022]
Abstract
BACKGROUND The enormous and irresponsible use of antibiotics has led to the emergence of resistant strains of bacteria globally. A new approach to combat this crisis has been nutritional immunity limiting the availability of nutrients to pathogens. Targeting the siderophore biosynthetic pathway that helps in iron acquisition, an essential microelement in the bacterial system has been the topic of interest in recent days that backs the concept of nutritional immunity. Supporting this view, we have chosen to study a key enzyme in the biosynthetic pathway of putrebactin called putrescine monooxygenase (SpPMO) from Shewanella putrefaciens. In our previous study, we co-expressed putrescine monooxygenase recombinantly in Escherichia coli BL21 Star (DE3). The bioinformatic analysis and screening of inhibitors will broaden the scope of SpPMO as a drug target. RESULTS In the present study, we have analysed the physicochemical properties of the target enzyme and other N-hydroxylating monooxygenases (NMOs) using ExPASy server. The target enzyme SpPMO and most of the selected NMOs have a slightly acidic isoelectric point and are medially thermostable and generally insoluble. The multiple sequence alignment identified the GXGXX(N/A), DXXXFATGYXXXXP motives and conserved amino acids involved in FAD binding, NADP binding, secondary structure formation and substrate binding. The phylogenetic analysis indicated the distribution of the monooxygenases into different clades according to their substrate specificity. Further, a 3D model of SpPMO was predicted using I-TASSER online tool with DfoA from Erwinia amylovora as a template. The model was validated using the SAVES server and deposited to the Protein Model Database with the accession number PM0082222. The molecular docking analysis with different substrates revealed the presence of a putrescine binding pocket made of conserved amino acids and another binding pocket present on the surface of the protein wherein all other ligands interact with high binding affinity. The molecular docking of naturally occurring inhibitor molecules with SpPMO 3D model identified curcumin and niazirin with 1.83 and 2.81 μM inhibition constants as two promising inhibitors. Further studies on kinetic parameters of curcumin and niazirin inhibitors in vitro determined the Ki to be 2.6±0.0036 μM and 18.38±0.008 μM respectively. CONCLUSION This analysis will help us understand the structural, phylogenetic and drug target aspects of putrescine monooxygenase from Shewanella putrefaciens-95 in detail. It sheds light on the precautionary measures that can be developed to inhibit the enzyme and thereby the secondary infections caused by them.
Collapse
Affiliation(s)
- Anil H Shyam Mohan
- Department of Biotechnology, Dayananda Sagar College of Engineering, Kumaraswamy Layout, Shavige Malleswara Hills, Bengaluru-78, Karnataka, India
| | - Saroja Narsing Rao
- Pesticide Residue and Food Quality Analysis Laboratory, University of Agricultural Sciences, Raichur, Karnataka, 584104, India.
| | - Srividya D
- Department of Biotechnology, Davangere University, Shivagangothri, Davangere, Karnataka, 577007, India
| | - N Rajeswari
- Department of Biotechnology, Dayananda Sagar College of Engineering, Kumaraswamy Layout, Shavige Malleswara Hills, Bengaluru-78, Karnataka, India
| |
Collapse
|
25
|
Zhao Y, Wang W, Yao J, Wang X, Liu D, Wang P. The HipAB Toxin-Antitoxin System Stabilizes a Composite Genomic Island in Shewanella putrefaciens CN-32. Front Microbiol 2022; 13:858857. [PMID: 35387082 PMCID: PMC8978831 DOI: 10.3389/fmicb.2022.858857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 02/24/2022] [Indexed: 11/25/2022] Open
Abstract
Composite genomic islands (GIs) are useful models for studying GI evolution if they can revert into the previous components. In this study, CGI48—a 48,135-bp native composite GI that carries GI21, whose homologies specifically integrated in the conserved yicC gene—were identified in Shewanella putrefaciens CN-32. CGI48 was integrated into the tRNATrp gene, which is a conserved gene locus for the integration of genomic islands in Shewanella. Upon expressing integrase and excisionase, CGI48 and GI21 are excised from chromosomes via site-specific recombination. The shorter attachment sites of GI21 facilitated the capture of GI21 into CGI48. Moreover, GI21 encodes a functional HipAB toxin–antitoxin system, thus contributing to the maintenance of CGI48 in the host bacteria. This study provides new insights into GI evolution by performing the excision process of the inserting GI and improves our understanding of the maintenance mechanisms of composite GI.
Collapse
Affiliation(s)
- Yi Zhao
- College of Life Sciences, Hebei Normal University, Shijiazhuang, China
| | - Weiquan Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jianyun Yao
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Xiaoxue Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Dong Liu
- College of Life Sciences, Hebei Normal University, Shijiazhuang, China
| | - Pengxia Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.,University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
26
|
Benaissa E, Maleb A, Elouennass M. Shewanella putrefaciens: a rare cause of purulent otorrhoea. Access Microbiol 2022; 4:000469.v3. [PMID: 36910504 PMCID: PMC9996131 DOI: 10.1099/acmi.0.000469.v3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 09/01/2022] [Indexed: 12/12/2022] Open
Abstract
Shewanella putrefaciens is a Gram-negative, non-fermenting, motile and oxidase-positive bacillus. Its incrimination in human pathology is very rare, although there has been a resurgence in Shewanella infections in recent years. We report the first case in Morocco of a purulent otorrhoea caused by S. putrefaciens , resistant to conventional treatment, occurring in a 25-year-old female, afebrile, without deterioration of the general state and possibly acquired during sea bathing. We also describe the bacteriological characteristics of and antibiotic susceptibility results for the isolate.
Collapse
Affiliation(s)
- Elmostafa Benaissa
- Epidemiology and Bacterial Resistance Research Team/BIO-INOVA Centre, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco.,Department of Bacteriology, Mohammed V Military Teaching Hospital, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco
| | - Adil Maleb
- Laboratory of Microbiology, Mohammed VI University Hospital, Faculty of Medicine and Pharmacy, University Mohammed I, Oujda, Morocco
| | - Mostafa Elouennass
- Epidemiology and Bacterial Resistance Research Team/BIO-INOVA Centre, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco.,Department of Bacteriology, Mohammed V Military Teaching Hospital, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco
| |
Collapse
|
27
|
Yi Z, Xie J. Comparative Proteomics Reveals the Spoilage-Related Factors of Shewanella putrefaciens Under Refrigerated Condition. Front Microbiol 2021; 12:740482. [PMID: 34925259 PMCID: PMC8678035 DOI: 10.3389/fmicb.2021.740482] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 11/09/2021] [Indexed: 11/13/2022] Open
Abstract
Shewanella putrefaciens is a microorganism with strong spoilage potential for aquatic products. This study aimed to investigate the potential spoilage factors of S. putrefaciens by comparative proteomic analysis. The spoilage potential of two strains of S. putrefaciens (00A and 00B) isolated from chilled spoiled bigeye tuna was investigated. The results of total volatile basic nitrogen (TVB-N), trimethylamine (TMA) in fish inoculated with S. putrefaciens, extracellular protease activity of S. putrefaciens, and degradation of fish proteins indicated that the spoilage potential of S. putrefaciens 00A was much higher than that of 00B. Fish proteins are usually degraded by spoilage microorganism proteases into small molecular peptides and amino acids, which are subsequently degraded into spoilage metabolites in bacterial cells, leading to deterioration of fish quality. Thus, proteomic analysis of the extracellular and intracellular proteins of 00A vs. 00B was performed. The results indicated that the intracellular differentially expressed protein (IDEP) contained 243 upregulated proteins and 308 downregulated proteins, while 78 upregulated proteins and 4 downregulated proteins were found in the extracellular differentially expressed protein (EDEP). GO annotation revealed that IDEP and EDEP were mainly involved in cellular and metabolic processes. KEGG annotation results showed that the upregulated proteins in IDEP were mainly involved in sulfur metabolism, amino acid metabolism, and aminoacyl-tRNA biosynthesis, while downregulated proteins were related to propanoate metabolism. In contrast, EDEP of KEGG annotation was mainly involved in ribosomes, quorum sensing, and carbohydrate metabolism. Proteins associated with spoilage containing sulfur metabolism (sulfite reductase, sulfate adenylyltransferase, adenylyl-sulfate kinase), amino acid metabolism (biosynthetic arginine decarboxylase, histidine ammonia-lyase), trimethylamine metabolism (trimethylamine-N-oxide reductase), and extracellular proteins (ATP-dependent Clp protease proteolytic subunit) were identified as upregulated. These proteins may play a key role in the spoilage potential of S. putrefaciens. These findings would contribute to the identification of key spoilage factors and understanding of the spoilage mechanism of microorganisms.
Collapse
Affiliation(s)
- Zhengkai Yi
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai Ocean University, Shanghai, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai, China
| | - Jing Xie
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai Ocean University, Shanghai, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai, China
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai Ocean University, Shanghai, China
- Collaborative Innovation Center of Seafood Deep Processing, Ministry of Education, Dalian, China
| |
Collapse
|
28
|
Wang XY, Xie J. Comparison of Physicochemical Changes and Water Migration of Acinetobacter johnsonii, Shewanella putrefaciens, and Cocultures From Spoiled Bigeye Tuna ( Thunnus obesus) During Cold Storage. Front Microbiol 2021; 12:727333. [PMID: 34777276 PMCID: PMC8586447 DOI: 10.3389/fmicb.2021.727333] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 10/11/2021] [Indexed: 11/23/2022] Open
Abstract
This study investigates the physicochemical changes and water migration of Acinetobacter johnsonii (A), Shewanella putrefaciens (S), and cocultured A. johnsonii and S. putrefaciens (AS) inoculated into bigeye tuna during cold storage. The physicochemical indexes [fluorescence ratio (FR), total volatile base nitrogen (TVB-N), thiobarbituric acid (TBA), trimethylamine (TMA), peroxide value (POV), and pH] of bigeye tuna increased cold storage. A significant decrease in trapped water was found in the AS samples, and direct monitoring of the water dynamics was provided by low-field nuclear magnetic resonance. Samples inoculated with A. johnsonii and S. putrefaciens also induced the degradation of myofibrillar proteins and weakness of some Z-lines and M-lines. Higher values of physicochemical indexes and water dynamics were shown in the coculture of S. putrefaciens and A. johnsonii than in the other groups. Therefore, this paper reveals that the coculture of A. johnsonii and S. putrefaciens resulted in a bigeye tuna that was more easily spoiled when compared to the single culture. This study provides insight into the spoilage potential of A. johnsonii and S. putrefaciens during cold storage, which further assists in the application of appropriate technologies to keep the freshness of aquatic foods.
Collapse
Affiliation(s)
- Xin-Yun Wang
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering Shanghai Ocean University, Shanghai, China
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
| | - Jing Xie
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering Shanghai Ocean University, Shanghai, China
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
| |
Collapse
|
29
|
Benaissa E, Abassor T, Oucharqui S, Maleb A, Elouennass M. Shewanella putrefaciens: A cause of bacteremia not to neglect. IDCases 2021; 26:e01294. [PMID: 34621619 DOI: 10.1016/j.idcr.2021.e01294] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/22/2021] [Accepted: 09/22/2021] [Indexed: 12/02/2022] Open
Abstract
Shewanella putrefaciens is a Gram-negative bacillus and marine pathogen that rarely causes disease in humans. We report the first Moroccan case of multidrug-resistant Shewanella putrefaciens bacteremia and describe the bacteriological, clinical, and antibiogram characteristics of this isolate, which was repeatedly isolated from the blood of a 66-year-old hypertensive man who underwent femoral coronary angiography after a myocardial infarction.
Collapse
|
30
|
Yi Z, Xie J. Prediction in the Dynamics and Spoilage of Shewanella putrefaciens in Bigeye Tuna ( Thunnus obesus) by Gas Sensors Stored at Different Refrigeration Temperatures. Foods 2021; 10:foods10092132. [PMID: 34574241 PMCID: PMC8472656 DOI: 10.3390/foods10092132] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/31/2021] [Accepted: 09/07/2021] [Indexed: 12/02/2022] Open
Abstract
Shewanella putrefaciens have a faster growth rate and strong spoilage potential at low temperatures for aquatic products. This study developed a nondestructive method for predicting the kinetic growth and spoilage of S. putrefaciens in bigeye tuna during cold storage at 4, 7 and 10 °C by electronic nose. According to the responses of electronic nose sensor P30/2, the fitted primary kinetic models (Gompertz and logistic models) and secondary model (square root function model) were able to better simulate the dynamic growth of S. putrefaciens, with high R2 and low RMSE values in the range of 0.96–0.99 and 0.021–0.061, respectively. A partial least squares (PLS) regression model based on both electronic nose sensor response values and electrical conductivity (EC) values predicted spoilage of S. putrefaciens in bigeye tuna more accurately than the PLS model based on sensor signal values only. In addition, SPME/GC-MS analysis suggested that 1-octen-3-ol, 2-nonanone, 2-heptanone, dimethyl disulfide and methylamine, N, N-dimethyl- are the key VOCs of tuna inoculated with S. putrefaciens.
Collapse
Affiliation(s)
- Zhengkai Yi
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China;
| | - Jing Xie
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China;
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai 201306, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing & Preservation, Shanghai 201306, China
- Correspondence: ; Tel.: +86-021-6190-0391
| |
Collapse
|
31
|
Han J, Meng X, Shen H, Luo W, Yao S, Yang J, Zhu Q, Tian Y, Wang S. Purification, molecular characterization of Lactocin 63 produced by Lactobacillus coryniformis FZU63 and its antimicrobial mode of action against Shewanella putrefaciens. Appl Microbiol Biotechnol 2021; 105:6921-30. [PMID: 34476515 DOI: 10.1007/s00253-021-11503-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 06/22/2021] [Accepted: 08/05/2021] [Indexed: 10/20/2022]
Abstract
Bacteriocins derived from lactic acid bacteria (LAB) are well recognized as promising food preservative due to high safety and potent antibacterial activity against foodborne pathogens and spoilage bacteria. In this study, an antimicrobial agent-producing strain FZU63 from Chinese sauerkraut was identified as Lactobacillus coryniformis based on physio-biochemical characterization and 16S rDNA sequence analysis. In addition, a bacteriocin was purified from the culture supernatant of L. coryniformis FZU63, and its molecular mass was determined as 1493.709 Da. Moreover, the amino acid sequence of the bacteriocin was predicted to be RQQPMTLDYRW-NH2 using nanoliter/microliter liquid chromatography combined with triple quadrupole-linear ion trap tandem mass spectrometry and was named as Lactocin 63. Furthermore, Lactocin 63 displays potent antimicrobial activity against the tested Gram-positive and negative bacteria based on the results of determining MICs. Subsequently, the action mode of Lactocin 63 against Shewanella putrefaciens was investigated. The results demonstrated that Lactocin 63 targets and is adsorbed onto the bacterial cell wall and membrane and then disrupts cytoplasmic membrane, which is leading to leakage of cytoplasm according to the results of flow cytometry analysis and the observation of cellular ultra-structure using confocal laser microscopy and atomic force microscopy. Collectively, these results are helpful and providing the theoretical base for developing and applying LAB-derived bacteriocins as promising bio-preservatives to combat foodborne pathogens and spoilage bacteria in seafood industries.Key points• A bacteriocin-producing strain Lactobacillus coryniformis was isolated.• A novel bacteriocin produced by Lactobacillus coryniformis FZU63 was characterized.• Action mechanism of the bacteriocin against S. putrefaciens was elucidated in vitro.
Collapse
|
32
|
Mayer B, Schwan M, Oviedo-Bocanegra LM, Bange G, Thormann KM, Graumann PL. Dynamics of Bacterial Signal Recognition Particle at a Single Molecule Level. Front Microbiol 2021; 12:663747. [PMID: 33995327 PMCID: PMC8120034 DOI: 10.3389/fmicb.2021.663747] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 03/18/2021] [Indexed: 11/21/2022] Open
Abstract
We have studied the localization and dynamics of bacterial Ffh, part of the SRP complex, its receptor FtsY, and of ribosomes in the Gamma-proteobacterium Shewanella putrefaciens. Using structured illumination microscopy, we show that ribosomes show a pronounced accumulation at the cell poles, whereas SRP and FtsY are distributed at distinct sites along the cell membrane, but they are not accumulated at the poles. Single molecule dynamics can be explained by assuming that all three proteins/complexes move as three distinguishable mobility fractions: a low mobility/static fraction may be engaged in translation, medium-fast diffusing fractions may be transition states, and high mobility populations likely represent freely diffusing molecules/complexes. Diffusion constants suggest that SRP and FtsY move together with slow-mobile ribosomes. Inhibition of transcription leads to loss of static molecules and reduction of medium-mobile fractions, in favor of freely diffusing subunits, while inhibition of translation appears to stall the medium mobile fractions. Depletion of FtsY leads to aggregation of Ffh, but not to loss of the medium mobile fraction, indicating that Ffh/SRP can bind to ribosomes independently from FtsY. Heat maps visualizing the three distinct diffusive populations show that while static molecules are mostly clustered at the cell membrane, diffusive molecules are localized throughout the cytosol. The medium fast populations show an intermediate pattern of preferential localization, suggesting that SRP/FtsY/ribosome transition states may form within the cytosol to finally find a translocon.
Collapse
Affiliation(s)
- Benjamin Mayer
- LOEWE Center for Synthetic Microbiology, SYNMIKRO, Marburg, Germany
- Department of Chemistry, Philipps Universität Marburg, Marburg, Germany
| | - Meike Schwan
- Institut für Mikrobiologie und Molekularbiologie, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Luis M. Oviedo-Bocanegra
- LOEWE Center for Synthetic Microbiology, SYNMIKRO, Marburg, Germany
- Department of Chemistry, Philipps Universität Marburg, Marburg, Germany
| | - Gert Bange
- LOEWE Center for Synthetic Microbiology, SYNMIKRO, Marburg, Germany
- Department of Chemistry, Philipps Universität Marburg, Marburg, Germany
| | - Kai M. Thormann
- Institut für Mikrobiologie und Molekularbiologie, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Peter L. Graumann
- LOEWE Center for Synthetic Microbiology, SYNMIKRO, Marburg, Germany
- Department of Chemistry, Philipps Universität Marburg, Marburg, Germany
| |
Collapse
|
33
|
Yang F, Jian H, Wang C, Wang Y, Li E, Sun H. Effects of biochar on biodegradation of sulfamethoxazole and chloramphenicol by Pseudomonas stutzeri and Shewanella putrefaciens: Microbial growth, fatty acids, and the expression quantity of genes. J Hazard Mater 2021; 406:124311. [PMID: 33257131 DOI: 10.1016/j.jhazmat.2020.124311] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 09/27/2020] [Accepted: 10/15/2020] [Indexed: 06/12/2023]
Abstract
An incubation experiment was conducted to investigate whether different biochar could enhance the biodegradation of sulfamethoxazole (SMX) and chloramphenicol (CAP). During incubation in nutrient medium solution, the degradation efficiencies of SMX by P. stutzeri and S. putrefaciens obtained 61.79% and 68.67% respectively, while CAP was 85.75% and 85.70%. The biodegradation efficiencies of SMX and CAP increased for P. stutzeri cultured with biochar and increased for S. putrefaciens cultured with high-concentration biochar (500, 1,000, 2,000 mg L-1). Additionally, TOC and TN contents were significantly decreased during the biodegradation process. Hence, the effects of biochar on microbial growth, fatty acids and expression genes, biodegradation products were studied. The content of bacteria, saturated fatty acids and expression genes showed a positive correlation with the content of TOC released from biochar, while the biodegradation products would not change when bacteria was cultured with biochar. These indicated that biochar improved the antibiotics biodegradation efficiencies via involvement in the bacterial growth, changing the components of fatty acids, increasing the expression quantity of genes. This research suggests that micro-biological degradation with biochar is a promising technology to treat specific antibiotics in the environment.
Collapse
Affiliation(s)
- Fang Yang
- Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China
| | - Hongxian Jian
- Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China
| | - Cuiping Wang
- Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
| | - Yu Wang
- Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China
| | - Erhu Li
- Tianjin Agriculture Ecological Environment Monitoring and Agricultural Product Quality Testing Centre, Tianjin 300191, China
| | - Hongwen Sun
- Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China
| |
Collapse
|
34
|
Guo F, Liang Q, Zhang M, Chen W, Chen H, Yun Y, Zhong Q, Chen W. Antibacterial Activity and Mechanism of Linalool against Shewanella putrefaciens. Molecules 2021; 26:molecules26010245. [PMID: 33466475 PMCID: PMC7796449 DOI: 10.3390/molecules26010245] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 12/24/2020] [Accepted: 12/31/2020] [Indexed: 11/26/2022] Open
Abstract
The demand for reduced chemical preservative usage is currently growing, and natural preservatives are being developed to protect seafood. With its excellent antibacterial properties, linalool has been utilized widely in industries. However, its antibacterial mechanisms remain poorly studied. Here, untargeted metabolomics was applied to explore the mechanism of Shewanella putrefaciens cells treated with linalool. Results showed that linalool exhibited remarkable antibacterial activity against S. putrefaciens, with 1.5 µL/mL minimum inhibitory concentration (MIC). The growth of S. putrefaciens was suppressed completely at 1/2 MIC and 1 MIC levels. Linalool treatment reduced the membrane potential (MP); caused the leakage of alkaline phosphatase (AKP); and released the DNA, RNA, and proteins of S. putrefaciens, thus destroying the cell structure and expelling the cytoplasmic content. A total of 170 differential metabolites (DMs) were screened using metabolomics analysis, among which 81 species were upregulated and 89 species were downregulated after linalool treatment. These DMs are closely related to the tricarboxylic acid (TCA) cycle, glycolysis, amino acid metabolism, pantothenate and CoA biosynthesis, aminoacyl-tRNA biosynthesis, and glycerophospholipid metabolism. In addition, linalool substantially affected the activity of key enzymes, such as succinate dehydrogenase (SDH), pyruvate kinase (PK), ATPase, and respiratory chain dehydrogenase. The results provided some insights into the antibacterial mechanism of linalool against S. putrefaciens and are important for the development and application of linalool in seafood preservation.
Collapse
Affiliation(s)
- Fengyu Guo
- College of Food Science and Technology, Hainan University, Haikou 570228, China; (F.G.); (Q.L.); (M.Z.); (W.C.); (H.C.); (Y.Y.)
- Key Laboratory of Food Nutrition and Functional Food of Hainan Province, Haikou 570228, China
- Hainan Provincial Engineering Research Center of Aquatic Resources Efficient Utilization in the South China Sea, Haikou 570228, China
| | - Qiong Liang
- College of Food Science and Technology, Hainan University, Haikou 570228, China; (F.G.); (Q.L.); (M.Z.); (W.C.); (H.C.); (Y.Y.)
| | - Ming Zhang
- College of Food Science and Technology, Hainan University, Haikou 570228, China; (F.G.); (Q.L.); (M.Z.); (W.C.); (H.C.); (Y.Y.)
| | - Wenxue Chen
- College of Food Science and Technology, Hainan University, Haikou 570228, China; (F.G.); (Q.L.); (M.Z.); (W.C.); (H.C.); (Y.Y.)
- Key Laboratory of Food Nutrition and Functional Food of Hainan Province, Haikou 570228, China
- Hainan Provincial Engineering Research Center of Aquatic Resources Efficient Utilization in the South China Sea, Haikou 570228, China
| | - Haiming Chen
- College of Food Science and Technology, Hainan University, Haikou 570228, China; (F.G.); (Q.L.); (M.Z.); (W.C.); (H.C.); (Y.Y.)
- Key Laboratory of Food Nutrition and Functional Food of Hainan Province, Haikou 570228, China
- Hainan Provincial Engineering Research Center of Aquatic Resources Efficient Utilization in the South China Sea, Haikou 570228, China
| | - Yonghuan Yun
- College of Food Science and Technology, Hainan University, Haikou 570228, China; (F.G.); (Q.L.); (M.Z.); (W.C.); (H.C.); (Y.Y.)
- Key Laboratory of Food Nutrition and Functional Food of Hainan Province, Haikou 570228, China
- Hainan Provincial Engineering Research Center of Aquatic Resources Efficient Utilization in the South China Sea, Haikou 570228, China
| | - Qiuping Zhong
- College of Food Science and Technology, Hainan University, Haikou 570228, China; (F.G.); (Q.L.); (M.Z.); (W.C.); (H.C.); (Y.Y.)
- Key Laboratory of Food Nutrition and Functional Food of Hainan Province, Haikou 570228, China
- Hainan Provincial Engineering Research Center of Aquatic Resources Efficient Utilization in the South China Sea, Haikou 570228, China
- Correspondence: (Q.Z.); (W.C.)
| | - Weijun Chen
- College of Food Science and Technology, Hainan University, Haikou 570228, China; (F.G.); (Q.L.); (M.Z.); (W.C.); (H.C.); (Y.Y.)
- Key Laboratory of Food Nutrition and Functional Food of Hainan Province, Haikou 570228, China
- Hainan Provincial Engineering Research Center of Aquatic Resources Efficient Utilization in the South China Sea, Haikou 570228, China
- Correspondence: (Q.Z.); (W.C.)
| |
Collapse
|
35
|
Hou W, Zhang Y, Zhang Y, Yue Q, Wang L, Min T, Wang H. Label-free proteomics study on Shewanella putrefaciens regulated by ε-poly-lysine treatment. J Appl Microbiol 2021; 131:791-800. [PMID: 33289172 DOI: 10.1111/jam.14954] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 11/09/2020] [Accepted: 11/26/2020] [Indexed: 01/19/2023]
Abstract
AIMS The purpose of this study was to investigate the regulatory mechanism of ε-PL on Shewanella putrefaciens. METHODS AND RESULTS Proteomics analysis of inhibitory effect of ε-PL against S. putrefaciens was performed by label-free quantitative assay based on high-resolution mass spectrometry (MS). Quantification of 2206 proteins was obtained with high confidence, and a total of 36 differentially expressed proteins (DEPs), with 10 and 26 proteins showing upregulation and downregulation, respectively, were identified. Upon Go functional enrichment, 11, 5 and 8 specific Go terms in biological processes, molecular functions and cellular components were identified, respectively. Six KEGG pathways, including 'ribosome', were significantly enriched. Among the ribosome pathway, there were seven DEPs and all of them were distributed on large and small subunits of ribosome. CONCLUSIONS The significant downregulation of proteins, large subunits of ribosomal proteins RP-L18, L30 and L27, small subunits ribosomal proteins S16 and S20, and RNA polymerase β' subunit protein rpoC were the critical action sites of ε-PL to inhibit S. putrefaciens growth. SIGNIFICANCE AND IMPACT OF THE STUDY Shewanella putrefaciens is one of the representative fish-spoilage bacteria regardless of fish type, and poses significant problems for the fish brewery. A better understanding of the antibacterial mechanism of ε-PL on S. putrefaciens could make important contributions to development of biological control strategies of these economically important pathogens.
Collapse
Affiliation(s)
- W Hou
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, Hubei, P.R. China
| | - Y Zhang
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, Hubei, P.R. China
| | - Y Zhang
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, Hubei, P.R. China
| | - Q Yue
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, Hubei, P.R. China
| | - L Wang
- School of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, Hubei, P.R. China
| | - T Min
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, Hubei, P.R. China
| | - H Wang
- School of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, Hubei, P.R. China
| |
Collapse
|
36
|
Lee BH, Wu SC, Shen TL, Hsu YY, Chen CH, Hsu WH. The applications of Lactobacillus plantarum-derived extracellular vesicles as a novel natural antibacterial agent for improving quality and safety in tuna fish. Food Chem 2021; 340:128104. [PMID: 33010644 DOI: 10.1016/j.foodchem.2020.128104] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 09/02/2020] [Accepted: 09/12/2020] [Indexed: 12/16/2022]
Abstract
Bacteria release membrane vesicles into the extracellular environment but which activity is unclear. We investigated the applications of extracellular vesicles (EVs) isolated from probiotic Lactobacillus plantarum to protect tuna fish against spoilage and quality loss in this study. A significant difference was found in EVs size obtained from L. plantarum after 8, 24, and 48 hr incubation. The L. plantarum-derived EVs were collected and used to confirm the anti-bacterial activity versus Shewanella putrefaciens. Finally, the tuna fish was stored at 4 °C for 5 days after coating with EVs or sodium erythorbate, and the quality indexes were assayed. Results indicated that EVs markedly inhibited oxidation reaction, total volatile base nitrogen (TVBN), peroxide value (PV), malondialdehyde (MDA), and bacteria levels. These results finding out that EVs from L. plantarum may have potential for application in food storage technology. Overall, we indicated this new material may be developed as an anti-bacterial agent for prolonging the shelf life of tuna fish.
Collapse
|
37
|
Oh HB, Yoon SI. Structural analysis of a Simpl-like protein from Campylobacter jejuni. Biochem Biophys Res Commun 2020; 529:270-276. [PMID: 32703422 DOI: 10.1016/j.bbrc.2020.05.211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 05/28/2020] [Indexed: 10/24/2022]
Abstract
Signaling molecule that interacts with mouse pelle-like kinase (Simpl) is an animal protein that contributes to the regulation of inflammatory responses. Although Simpl-like proteins (SLPs) are mainly found in bacteria, functional and structural studies on bacterial SLPs are limited to BP26, a periplasmic protein from Brucella species. We identified a group of bacterial SLPs, including Campylobacter jejuni SLP (cjSLP) and Shewanella putrefaciens SLP (spSLP), that exhibit significant sequence variation from Simpl and BP26. To address the structural and oligomeric diversities of SLPs, we determined the crystal structure of cjSLP and performed a comparative analysis of SLP structures. cjSLP adopts a boomerang-shaped, two-domain structure, and each domain of cjSLP adopts an α-helix-decorated β-sheet structure as observed in BP26. This observation suggests that the duplicated α/β structure would be the canonical fold of the Simpl family. Despite the fold similarity, cjSLP exhibits a more open interdomain organization than BP26 and displays unique local structural features that are not observed in BP26. Furthermore, cjSLP and its ortholog spSLP are monomeric in solution in contrast to the hexadecameric assembly of BP26. Therefore, we conclude that cjSLP represents a unique bacterial SLP group that is distinct from BP26 in both structures and oligomeric states.
Collapse
Affiliation(s)
- Han Byeol Oh
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Sung-Il Yoon
- Division of Biomedical Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, 24341, Republic of Korea.
| |
Collapse
|
38
|
Wang J, Chi Z, Zhao K, Wang H, Zhang X, Xu F, Shao X, Wei Y. A transcriptome analysis of the antibacterial mechanism of flavonoids from Sedum aizoon L. against Shewanella putrefaciens. World J Microbiol Biotechnol 2020; 36:94. [PMID: 32562062 DOI: 10.1007/s11274-020-02871-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 06/13/2020] [Indexed: 02/06/2023]
Abstract
Flavonoids from Sedum aizoon L. (FSAL) possess prominent antibacterial activity against Shewanella putrefaciens isolated from sea food. In the current study, the involved molecular mechanisms were investigated using transcriptome analyses combined with bioinformatics analysis in vitro for the first time. Results showed that treatment of FSAL (1.0 MIC) damaged the permeability and integrity of cell membrane and induced 721 differentially expressed genes (DEGs) in tested bacteria at transcriptional levels, including 107 DEGs were up-regulated and 614 DEGs were down-regulated. In addition, the RNA-Seq analysis revealed that the majority of DEGs mainly involved in pathways of lipopolysaccharide biosynthesis, glycerophospholipid metabolism, biosynthesis of amino acids, purine metabolism, ABC transporters and response to stimulus. In summary, the integrated results indicated that the intervention of FSAL induced destruction of cell wall and membrane, disorder of the metabolic process and redox balance, and damage of nucleic acids in S. putrefaciens, at last resulted in the death of cells. This study provided new insights into the anti- S. putrefaciens molecular mechanism underlying the treatment of FSAL, which may be served as the basis guide for identifying potential antimicrobial targets and application of FSAL in food safety.
Collapse
|
39
|
Yan J, Xie J. Comparative Proteome Analysis of Shewanella putrefaciens WS13 Mature Biofilm Under Cold Stress. Front Microbiol 2020; 11:1225. [PMID: 32582122 PMCID: PMC7296144 DOI: 10.3389/fmicb.2020.01225] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 05/14/2020] [Indexed: 12/19/2022] Open
Abstract
Worldwide, Shewanella putrefaciens is the predominant seafood spoilage microorganism during cold storage. This bacterium can attach to biotic/abiotic surfaces to form biofilms which contribute to seafood quality degradation and shelf-life reduction. The mechanism of S. putrefaciens biofilm formation is not yet described. Crystal violet staining in combination with confocal laser scanning microscopy (CLSM) was used to study the sequence of events leading to the establishment of a mature biofilm at 4, 15, and 30°C. In addition, the main chemical constituents of the mature biofilm were determined by Raman spectroscopy (RM), whereas, comparative proteomic analysis was used to quantify changes in metabolic pathways and to find out underlying protein determinants. The physical dimensions of the mature biofilm, i.e., biomass, biovolume, and mean thickness, were higher at 4°C when compared to 15 and 30°C. The variations of proteins measured by RM confirmed the importance of proteins during the formation of a mature biofilm. Comparative proteomic analysis showed that siderophore and iron chelate transport proteins were down-regulated during mature biofilm formation. The down-regulated aforementioned proteins are involved in promoting iron storage in response to a higher demand for metabolic energy, whereas, the upregulated proteins of the sulfur relay system, pyrimidine metabolism, and purine metabolism are related to bacterial adaptability. Synthesis of proteins related to cold stress was increased and proteins involved in aminoacyl-tRNA biosynthesis were up-regulated, whereas, proteins involved in aminopeptidase activity were down-regulated. Proteolysis to scavenge energy was reduced as proteins involved in pyrophosphatase activity were up-regulated. Also extracellular eDNA was found which may play an important role in maintaining the stability of mature S. putrefaciens biofilm structures under cold stress. This work provides a better understanding of the role of proteins in mature biofilms. In addition, the biofilm formation mechanism of a psychrotrophic spoilage bacterial species at low temperature is explored, which may contribute to generating biofilm controlling strategies during seafood preservation and processing.
Collapse
Affiliation(s)
- Jun Yan
- College of Food Science & Technology, Shanghai Ocean University, Shanghai, China
- Laboratory for Quality and Safety Risk Assessment of Aquatic Products in Storage and Preservation of Ministry of Agriculture and Rural Affairs, Shanghai Ocean University, Shanghai, China
| | - Jing Xie
- College of Food Science & Technology, Shanghai Ocean University, Shanghai, China
- Laboratory for Quality and Safety Risk Assessment of Aquatic Products in Storage and Preservation of Ministry of Agriculture and Rural Affairs, Shanghai Ocean University, Shanghai, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai Ocean University, Shanghai, China
- National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai, China
| |
Collapse
|
40
|
Gao X, Liu W, Mei J, Xie J. Quantitative Analysis of Cold Stress Inducing Lipidomic Changes in Shewanella putrefaciens Using UHPLC-ESI-MS/MS. Molecules 2019; 24:E4609. [PMID: 31888284 PMCID: PMC6943694 DOI: 10.3390/molecules24244609] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 12/08/2019] [Accepted: 12/13/2019] [Indexed: 02/06/2023] Open
Abstract
Shewanella putrefaciens is a well-known specific spoilage organism (SSO) and cold-tolerant microorganism in refrigerated fresh marine fish. Cold-adapted mechanism includes increased fluidity of lipid membranes by the ability to finely adjust lipids composition. In the present study, the lipid profile of S. putrefaciens cultivated at 30, 20, 10, 4, and 0 °C was explored using ultra-high-pressure liquid chromatography/electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) to discuss the effect of lipid composition on cold-adapted tolerance. Lipidomic analysis detected a total of 27 lipid classes and 606 lipid molecular species in S. putrefaciens cultivated at 30, 20, 10, 4, and 0 °C. S. putrefaciens cultivated at 30 °C (SP-30) had significantly higher content of glycerolipids, sphingolipids, saccharolipids, and fatty acids compared with that at 0 °C (SP-0); however, the lower content of phospholipids (13.97%) was also found in SP-30. PE (30:0), PE (15:0/15:0), PE (31:0), PA (33:1), PE (32:1), PE (33:1), PE (25:0), PC (22:0), PE (29:0), PE (34:1), dMePE (15:0/16:1), PE (31:1), dMePE (15:1/15:0), PG (34:2), and PC (11:0/11:0) were identified as the most abundant lipid molecular species in S. putrefaciens cultivated at 30, 20, 10, 4, and 0 °C. The increase of PG content contributes to the construction of membrane lipid bilayer and successfully maintains membrane integrity under cold stress. S. putrefaciens cultivated at low temperature significantly increased the total unsaturated liquid contents but decreased the content of saturated liquid contents.
Collapse
Affiliation(s)
- Xin Gao
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; (X.G.); (W.L.)
- National Experimental Teaching Demonstration Center for Food Science Engineering, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai 201306, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai 201306, China
- School of Health and Social Care, Shanghai Urban Construction Vocational College, Shanghai 201415, China
| | - Wenru Liu
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; (X.G.); (W.L.)
- National Experimental Teaching Demonstration Center for Food Science Engineering, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai 201306, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai 201306, China
| | - Jun Mei
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; (X.G.); (W.L.)
- National Experimental Teaching Demonstration Center for Food Science Engineering, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai 201306, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai 201306, China
| | - Jing Xie
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; (X.G.); (W.L.)
- National Experimental Teaching Demonstration Center for Food Science Engineering, Shanghai Ocean University, Shanghai 201306, China
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai 201306, China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai 201306, China
| |
Collapse
|
41
|
Yuan W, Cheng J, Huang H, Xiong S, Gao J, Zhang J, Feng S. Optimization of cadmium biosorption by Shewanella putrefaciens using a Box-Behnken design. Ecotoxicol Environ Saf 2019; 175:138-147. [PMID: 30897412 DOI: 10.1016/j.ecoenv.2019.03.057] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 03/12/2019] [Accepted: 03/14/2019] [Indexed: 06/09/2023]
Abstract
Microbial adsorption of heavy metals has been attracted more interest in the recent years. However, there are very few studies in investigating the biosorption of heavy metals by Shewanella putrefaciens, which is a metal reducing bacterium. Firstly, the effects of contact time, pH value, temperature, biomass dosage and initial cadmium concentration on the cadmium adsorption by Shewanella putrefaciens were studied by single factor experiments. Then, the response surface methodology (RSM) based on Box-Behnken design was used to optimize the cadmium adsorption by Shewanella putrefaciens. The results showed that the empirical model was suitable for experimental data, and the maximum cadmium removal efficiency by Shewanella putrefaciens was 86.54% under the optimum conditions of contact time 4.0 days, pH value 5, initial cadmium concentration of 20 mg/L, which was further verified by experiments. In addition, scanning electron microscope - Energy Dispersive Spectrometer (SEM-EDS) analysis showed that the bacteria were seriously deformed, and a "bamboo" shape was observed on the surface which consisted of cadmium according to the EDS analysis. Fourier transform infrared spectroscopy (FT-IR) analysis was used to evaluate the possible functional groups involving in interaction between cells and metal ions. The results showed that the distribution of cadmium on the cell surface was related to the carboxyl, amide, hydroxyl and phosphoric acid groups of Shewanella putrefaciens. These studies can provide a comprehensive understanding of the process and mechanism of microbial removal of heavy metals, and theoretical support for the follow-up practice of using biological adsorbents to remediate heavy metal contaminated soil.
Collapse
Affiliation(s)
- Wenjuan Yuan
- Key Laboratory of Biological Resources and Ecological Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, PR China.
| | - Juan Cheng
- Key Laboratory of Biological Resources and Ecological Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, PR China.
| | - Hexiang Huang
- Institute of Materials, China Academy of Engineering Physics, Jiangyou, Sichuan, 621907, PR China.
| | - Suli Xiong
- Key Laboratory of Biological Resources and Ecological Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, PR China.
| | - Jingqi Gao
- Key Laboratory of Biological Resources and Ecological Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, PR China.
| | - Jie Zhang
- Key Laboratory of Biological Resources and Ecological Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, PR China.
| | - Su Feng
- Key Laboratory of Biological Resources and Ecological Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, PR China.
| |
Collapse
|
42
|
Pan T, Chen B. Facile fabrication of Shewanella@graphene core-shell material and its enhanced performance in nitrobenzene reduction. Sci Total Environ 2019; 658:324-332. [PMID: 30579190 DOI: 10.1016/j.scitotenv.2018.12.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Revised: 12/03/2018] [Accepted: 12/04/2018] [Indexed: 06/09/2023]
Abstract
A novel Shewanella@graphene core-shell composite material was fabricated following one-step bioreduction of graphene oxide (GO) by Shewanella putrefaciens CN-32. The surface properties and microstructures were characterized by FTIR, TG-DTG, SEM and TEM, which indicate that GO was effectively reduced to rGO and subsequently loaded onto the outer surface of the microbe Shewanella. CLSM was performed to get insight into the growth of the bacteria after core-shell materials formation. The reduction properties of Shewanella@graphene materials were evaluated using nitrobenzene, a representative model pollutant, as an electron acceptor. The reduction efficiency of Shewanella was improved by strengthening the contact among electron donors, electron shuttles and electron acceptors and changed with the proportions of core-shell materials. The optimal proportion of the core-shell material was OD600 = 0.6:GO = 10 mg/L, which was enhanced by the wrapped rGO and improved adsorption capability. The reduction rate was elevated 30% in comparison with pure Shewanella. In addition, the core-shell material exhibited a favorable recycling performance, which can be reused for at least five times. Facile fabrication and enhanced reduction performance of Shewanella@graphene core-shell composite endows this material with considerable potential in environmental remediation.
Collapse
Affiliation(s)
- Tingting Pan
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China
| | - Baoliang Chen
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China.
| |
Collapse
|
43
|
Seoane P, Tapia-Paniagua ST, Bautista R, Alcaide E, Esteve C, Martínez-Manzanares E, Balebona MC, Claros MG, Moriñigo MA. TarSynFlow, a workflow for bacterial genome comparisons that revealed genes putatively involved in the probiotic character of Shewanella putrefaciens strain Pdp11. PeerJ 2019; 7:e6526. [PMID: 30842906 PMCID: PMC6397758 DOI: 10.7717/peerj.6526] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 01/26/2019] [Indexed: 11/20/2022] Open
Abstract
Probiotic microorganisms are of great interest in clinical, livestock and aquaculture. Knowledge of the genomic basis of probiotic characteristics can be a useful tool to understand why some strains can be pathogenic while others are probiotic in the same species. An automatized workflow called TarSynFlow (Targeted Synteny Workflow) has been then developed to compare finished or draft bacterial genomes based on a set of proteins. When used to analyze the finished genome of the probiotic strain Pdp11 of Shewanella putrefaciens and genome drafts from seven known non-probiotic strains of the same species obtained in this work, 15 genes were found exclusive of Pdp11. Their presence was confirmed by PCR using Pdp11-specific primers. Functional inspection of the 15 genes allowed us to hypothesize that Pdp11 underwent genome rearrangements spurred by plasmids and mobile elements. As a result, Pdp11 presents specific proteins for gut colonization, bile salt resistance and gut pathogen adhesion inhibition, which can explain some probiotic features of Pdp11.
Collapse
Affiliation(s)
- Pedro Seoane
- Department of Molecular Biology and Biochemistry, Universidad de Málaga, Málaga, Spain
| | | | - Rocío Bautista
- Andalusian Platform for Bioinformatics, Universidad de Málaga, Málaga, Spain
| | - Elena Alcaide
- Department of Microbiology and Ecology, Universidad de Valencia, Valencia, Spain
| | - Consuelo Esteve
- Department of Microbiology and Ecology, Universidad de Valencia, Valencia, Spain
| | | | | | - M. Gonzalo Claros
- Department of Molecular Biology and Biochemistry, Universidad de Málaga, Málaga, Spain
- Andalusian Platform for Bioinformatics, Universidad de Málaga, Málaga, Spain
| | | |
Collapse
|
44
|
Xie J, Wang J, Lin J, Zhou X. The dynamic role of pH in microbial reduction of uranium(VI) in the presence of bicarbonate. Environ Pollut 2018; 242:659-666. [PMID: 30025339 DOI: 10.1016/j.envpol.2018.07.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 06/06/2018] [Accepted: 07/05/2018] [Indexed: 06/08/2023]
Abstract
The negative effect of carbonate on the rate and extent of bioreduction of aqueous U(VI) has been commonly reported. The solution pH is a key chemical factor controlling U(VI)aq species and the Gibbs free energy of reaction. Therefore, it is interesting to study whether the negative effect can be diminished under specific pH conditions. Experiments were conducted using Shewanella putrefaciens under anaerobic conditions with varying pH values (4-9) and bicarbonate concentrations ( [Formula: see text] , 0-50 mmol/L). The results showed a clear correlation between the pH-bioreduction edges of U(VI)aq and the [Formula: see text] . The specific pH at which the maximum bioreduction occurred (pHmbr) shifted from slightly basic to acidic pH (∼7.5-∼6.0) as the [Formula: see text] increased (2-50 mmol/L). At [Formula: see text] = 0, however, no pHmbr was observed in terms of increasing bioreduction with pH (∼100%, pH > 7). In the presence of [Formula: see text] , significant bioreduction was observed at pHmbr (∼100% at 2-30 mmol/L [Formula: see text] , 93.7% at 50 mmol/L [Formula: see text] ), which is in contrast to the previously reported infeasibility of bioreduction at high [Formula: see text] . The pH-bioreduction edges were almost comparable to the pH-biosorption edges of U(VI)aq on heat-killed cells, revealing that biosorption is favorable for bioreduction. The end product of U(VI)aq bioreduction was characterized as insoluble nanobiogenic uraninite by HRTEM. The redox potentials of the master complex species of U(VI)aq, such as [Formula: see text] , [Formula: see text] , and [Formula: see text] , were calculated to obtain insights into the thermodynamic reduction mechanism. The observed dynamic role of pH in bioreduction suggests the potential for bioremediation of uranium-contaminated groundwater containing high carbonate concentrations.
Collapse
Affiliation(s)
- Jinchuan Xie
- Northwest Institute of Nuclear Technology, P.O. Box 69-14, Xi'an City, Shanxi Province, 710024, PR China.
| | - Jinlong Wang
- Northwest Institute of Nuclear Technology, P.O. Box 69-14, Xi'an City, Shanxi Province, 710024, PR China
| | - Jianfeng Lin
- Northwest Institute of Nuclear Technology, P.O. Box 69-14, Xi'an City, Shanxi Province, 710024, PR China
| | - Xiaohua Zhou
- Northwest Institute of Nuclear Technology, P.O. Box 69-14, Xi'an City, Shanxi Province, 710024, PR China
| |
Collapse
|
45
|
Xie J, Lin J, Zhou X. pH-dependent microbial reduction of uranium(VI) in carbonate-free solutions: UV-vis, XPS, TEM, and thermodynamic studies. Environ Sci Pollut Res Int 2018; 25:22308-22317. [PMID: 29808405 DOI: 10.1007/s11356-018-2326-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 05/15/2018] [Indexed: 06/08/2023]
Abstract
U(VI)aq bioreduction has an important effect on the fate and transport of uranium isotopes in groundwater at nuclear test sites. In this study, we focus on the pH-dependent bioreduction of U(VI)aq in carbonate-free solutions and give mechanistic insight into the removal kinetics of U(VI)aq. An enhancement in the removal of U(VI)aq with increasing pH was observed within 5 h, e.g., from 19.4% at pH 4.52 to 99.7% at pH 8.30. The removal of U(VI)aq at pH 4.52 was due to the biosorption of U(VI)aq onto the living cells of Shewanella putrefaciens, as evidenced by the almost constant UV-vis absorption intensity of U(VI)aq immediately after contact with S. putrefaciens. Instead, the removal observed at pH 5.97 to 8.30 resulted from the bioreduction of U(VI)aq. The end product of U(VI)aq bioreduction was analyzed using XPS and HRTEM and identified as nanosized UO2. An increasing trend in the biosorption of U(VI)aq onto heat-killed cells was also observed, e.g., ~ 80% at pH 8.38. Evidently, the U(VI)aq that sorbed onto the living cells at pH > 4.52 was further reduced to UO2, although biosorption made a large contribution to the initial removal of U(VI)aq. These results may reveal the removal mechanism, in which the U(VI)aq that was sorbed onto cells rather than the U(VI)aq complexed in solution was reduced. The decreases in the redox potentials of the main complex species of U(VI)aq (e.g., [Formula: see text] and [Formula: see text]) with increasing pH support the proposed removal mechanism.
Collapse
Affiliation(s)
- Jinchuan Xie
- Northwest Institute of Nuclear Technology, P.O. Box 69-14, Xi'an City, 710024, Shanxi Province, People's Republic of China.
| | - Jianfeng Lin
- Northwest Institute of Nuclear Technology, P.O. Box 69-14, Xi'an City, 710024, Shanxi Province, People's Republic of China
| | - Xiaohua Zhou
- Northwest Institute of Nuclear Technology, P.O. Box 69-14, Xi'an City, 710024, Shanxi Province, People's Republic of China
| |
Collapse
|
46
|
Lyu F, Hong YL, Cai JH, Wei QQ, Zhou X, Ding YT, Liu ZF, Liu L. Antimicrobial effect and mechanism of cinnamon oil and gamma radiation on Shewanella putrefaciens. J Food Sci Technol 2018; 55:3353-61. [PMID: 30150793 DOI: 10.1007/s13197-018-3297-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 10/25/2017] [Accepted: 06/17/2018] [Indexed: 10/28/2022]
Abstract
The aims of this study were to observe the antimicrobial effect and mechanism of cinnamon oil combined with gamma radiation on Shewanella putrefaciens. Gamma radiation increased the antimicrobial activity of cinnamon oil, and the relative radiation sensitivity of gamma radiation on S. putrefaciens was increased by cinnamon oil. Gamma radiation significantly increased the changes of bacterial morphology, intra-adenosine 5'-triphosphate (intra-ATP) and extra-ATP concentrations and pHin value of S. putrefaciens treated cinnamon oil. Although, gamma radiation used alone didn't damage the bacterial morphology and ATP concentrations significantly. Gamma radiation assisted cinnamon oil to damage the cell permeability and integrity of S. putrefaciens, thus the combination of cinnamon oil and gamma radiation showed a better antimicrobial activity than used alone.
Collapse
|
47
|
Xu S, Sun T, Xu Q, Duan C, Dai Y, Wang L, Song Q. Preparation and Antibiofilm Properties of Zinc Oxide/Porous Anodic Alumina Composite Films. Nanoscale Res Lett 2018; 13:201. [PMID: 29987504 PMCID: PMC6037642 DOI: 10.1186/s11671-018-2568-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 05/03/2018] [Indexed: 06/08/2023]
Abstract
The PAA (porous anodic alumina) films were prepared by two-step anodic oxidation after different times, and then the ZnO/PAA composite films were prepared by sol-gel method on their surface. Meanwhile, the ZnO/PAA composite films were characterized by X-ray diffraction (XRD), thermogravimetric/differential thermal analyzer (TG/DTA), Fourier transform infrared spectrometer (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and water contact angle (CA). The antibiofilm properties of ZnO/PAA composite films on Shewanella putrefaciens were measured simultaneously. The results show that the micromorphologies of PAA and ZnO/PAA composite films are affected by second anodization time. ZnO is a hexagonal wurtzite structure, and ZnO particles with a diameter of 10-30 nm attach to the inner or outer surfaces of PAA. After being modified by Si69, the ZnO films translate from hydrophilia to hydrophobicity. The ZnO/PAA film with the optimal antibiofilm properties is prepared on the PAA surface by two-step anodization for 40 min. The adherence of Shewanella putrefaciens is restrained by its super-hydrophobicity, and the growth of biofilm bacteria is inhibited by its abundant ZnO particles.
Collapse
Affiliation(s)
- Shuying Xu
- School of Metallurgy, Northeastern University, Shenyang, 110004 China
- College of Chemistry and Chemical Engineering, Bohai University, Jinzhou, 121013 Liaoning China
| | - Tong Sun
- College of Food Science and Project Engineering, Bohai University, Jinzhou, 121013 Liaoning China
| | - Qian Xu
- State Key Laboratory of Advanced Special Steel, School of Materials Science and Engineering, Shanghai University, Shanghai, 200072 China
| | - Changping Duan
- College of Chemistry and Chemical Engineering, Bohai University, Jinzhou, 121013 Liaoning China
- The 404 Company Limited, China Nation Nuclear Corporation, Lanzhou, 730000 China
| | - Yue Dai
- College of Food Science and Project Engineering, Bohai University, Jinzhou, 121013 Liaoning China
- Liaoning Anjoy Food Co., Ltd., Anshan, 114100 Liaoning China
| | - Lili Wang
- Laboratory Management Center, Bohai University, Jinzhou, 121013 Liaoning China
| | - Qiushi Song
- School of Metallurgy, Northeastern University, Shenyang, 110004 China
| |
Collapse
|
48
|
Lyu F, Gao F, Ding Y. Effects of gamma radiation combined with cinnamon oil on qualities of smoked salmon slices inoculated with Shewanella putrefaciens. Food Sci Nutr 2018; 6:806-813. [PMID: 29983943 PMCID: PMC6021692 DOI: 10.1002/fsn3.608] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/06/2018] [Accepted: 01/17/2018] [Indexed: 12/02/2022] Open
Abstract
Smoked salmon slices inoculated with Shewanella putrefaciens were untreated (CK) or treated with 2 kGy gamma radiation (G), 1% (v/v) cinnamon oil (C), or the combination of them (G+C), and then packaged and stored at 4°C for 10 days. Microbiological and physiochemical analyses were then carried out. All treatments showed a better effect on inhibiting the increase in total viable counts, total volatile basic nitrogen, and thiobarbituric acid-reactive substances than CK, especially the treatment of G+C. In addition, the combination treatment also showed a best effect on retarding the reduction in polyunsaturated fatty acids of salmon samples in all treatments. These results indicated that treatments of gamma radiation and cinnamon oil on salmon samples, especially the combination treatment, can be used to maintain the quality of smoked salmon slices.
Collapse
Affiliation(s)
- Fei Lyu
- Department of Food Science and TechnologyZhejiang University of TechnologyHangzhouChina
| | - Fei Gao
- Department of Food Science and TechnologyZhejiang University of TechnologyHangzhouChina
| | - Yuting Ding
- Department of Food Science and TechnologyZhejiang University of TechnologyHangzhouChina
| |
Collapse
|
49
|
Ullah S, Mehmood H, Pervin N, Zeb H, Kamal KR, Liaqat S. Shewanella putrefaciens: An Emerging Cause of Nosocomial Pneumonia. J Investig Med High Impact Case Rep 2018; 6:2324709618775441. [PMID: 29796395 PMCID: PMC5956633 DOI: 10.1177/2324709618775441] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 03/19/2018] [Accepted: 03/21/2018] [Indexed: 11/23/2022] Open
Abstract
Gram-negative infections are a rising concern faced by the medical community. Approximately 30% of nosocomial bloodstream infections in intensive care units in the United States are caused by these gram-negative species. Emergence of multidrug-resistant organisms further complicate this issue. In this article, we report a case of an 84-year-old Caucasian male who was diagnosed with Shewanella pneumonia treated with cefepime with minimal to no improvement in his symptoms. To the best of our knowledge, this is the third reported case of Shewanella putrefaciens nosocomial pneumonia and first case of bacteremia secondary to pneumonia by Shewanella putrefaciens.
Collapse
Affiliation(s)
- Saad Ullah
- Temple University/Conemaugh Memorial Medical Center, Johnstown, PA, USA
| | - Hassan Mehmood
- Temple University/Conemaugh Memorial Medical Center, Johnstown, PA, USA
| | - Nawja Pervin
- Southern Illinois University, Springfield, IL, USA
| | - Hassan Zeb
- Temple University/Conemaugh Memorial Medical Center, Johnstown, PA, USA
| | | | - Sadaquat Liaqat
- Temple University/Conemaugh Memorial Medical Center, Johnstown, PA, USA
| |
Collapse
|
50
|
Wu X, Zou L, Huang Y, Qiao Y, Long ZE, Liu H, Li CM. Shewanella putrefaciens CN32 outer membrane cytochromes MtrC and UndA reduce electron shuttles to produce electricity in microbial fuel cells. Enzyme Microb Technol 2018; 115:23-8. [PMID: 29859599 DOI: 10.1016/j.enzmictec.2018.04.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 03/17/2018] [Accepted: 04/06/2018] [Indexed: 01/30/2023]
Abstract
The extracellular electron transfer (EET) process of Shewanella species is believed to be indispensable for their anaerobic respiration with an electrode. However, the function of outer membrane c-type cytochromes (OM c-Cyts, the primary components of the EET pathway) is still controversial. In this study, we investigated the effect of two OM c-Cyts (MtrC and UndA) of Shewanella putrefaciens CN32 with respect to electricity production and anodic EET efficiency. Deletion of the mtrC gene severely prolonged the microbial fuel cell (MFC) start-up time and decreased electricity production due to depressed flavin-mediated electron transfer, whereas deletion of the undA gene did not have a significant impact. Strikingly, the depression of EET by the deletion of mtrC could be partially relieved by acclimation, which might be due to an increase in the transmembrane transport of electron shuttles and/or the activation of other redox proteins. These results suggested that MtrC may be the primary reductase of flavins to ensure fast indirect EET, which plays a crucial role in MFC electricity generation.
Collapse
|