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Yuasa HJ. Unusual Evolution of Cephalopod Tryptophan Indole-Lyases. J Mol Evol 2023; 91:912-921. [PMID: 38007709 DOI: 10.1007/s00239-023-10144-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 11/07/2023] [Indexed: 11/28/2023]
Abstract
Tryptophan indole-lyase (TIL), a pyridoxal-5-phosphate-dependent enzyme, catalyzes the hydrolysis of L-tryptophan (L-Trp) to indole and ammonium pyruvate. TIL is widely distributed among bacteria and bacterial TILs consist of a D2-symmetric homotetramer. On the other hand, TIL genes are also present in several metazoans. Cephalopods have two TILs, TILα and TILβ, which are believed to be derived from a gene duplication that occurred before octopus and squid diverged. However, both TILα and TILβ individually contain disruptive amino acid substitutions for TIL activity, and neither was active when expressed alone. When TILα and TILβ were coexpressed, however, they formed a heterotetramer that exhibited low TIL activity. The loss of TIL activity of the heterotetramer following site-directed mutagenesis strongly suggests that the active heterotetramer contains the TILα/TILβ heterodimer. Metazoan TILs generally have lower kcat values for L-Trp than those of bacterial TILs, but such low TIL activity may be rather suitable for metazoan physiology, where L-Trp is in high demand. Therefore, reduced activity may have been a less likely target for purifying selection in the evolution of cephalopod TILs. Meanwhile, the unusual evolution of cephalopod TILs may indicate the difficulty of post-gene duplication evolution of enzymes with catalytic sites contributed by multiple subunits, such as TIL.
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Affiliation(s)
- Hajime Julie Yuasa
- Laboratory of Biochemistry, Department of Chemistry and Biotechnology, Faculty of Science and Technology, National University Corporation Kochi University, Kochi, 780-8520, Japan.
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2
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Hababag EAC, Cauilan A, Quintero D, Bermudes D. Tryptophanase Expressed by Salmonella Halts Breast Cancer Cell Growth In Vitro and Inhibits Production of Immunosuppressive Kynurenine. Microorganisms 2023; 11:1355. [PMID: 37317329 DOI: 10.3390/microorganisms11051355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 05/10/2023] [Accepted: 05/15/2023] [Indexed: 06/16/2023] Open
Abstract
Tryptophan is an essential amino acid required for tumor cell growth and is also the precursor to kynurenine, an immunosuppressive molecule that plays a role in limiting anticancer immunity. Tryptophanase (TNase) is an enzyme expressed by different bacterial species that converts tryptophan into indole, pyruvate and ammonia, but is absent in the Salmonella strain VNP20009 that has been used as a therapeutic delivery vector. We cloned the Escherichia coli TNase operon tnaCAB into the VNP20009 (VNP20009-tnaCAB), and were able to detect linear production of indole over time, using Kovács reagent. In order to conduct further experiments using the whole bacteria, we added the antibiotic gentamicin to stop bacterial replication. Using a fixed number of bacteria, we found that there was no significant effect of gentamicin on stationary phase VNP20009-tnaCAB upon their ability to convert tryptophan to indole over time. We developed a procedure to extract indole from media while retaining tryptophan, and were able to measure tryptophan spectrophotometrically after exposure to gentamicin-inactivated whole bacterial cells. Using the tryptophan concentration equivalent to that present in DMEM cell culture media, a fixed number of bacteria were able to deplete 93.9% of the tryptophan in the culture media in 4 h. In VNP20009-tnaCAB depleted tissue culture media, MDA-MB-468 triple negative breast cancer cells were unable to divide, while those treated with media exposed only to VNP20009 continued cell division. Re-addition of tryptophan to conditioned culture media restored tumor cell growth. Treatment of tumor cells with molar equivalents of the TNase products indole, pyruvate and ammonia only caused a slight increase in tumor cell growth. Using an ELISA assay, we confirmed that TNase depletion of tryptophan also limits the production of immunosuppressive kynurenine in IFNγ-stimulated MDA-MB-468 cancer cells. Our results demonstrate that Salmonella VNP20009 expressing TNase has improved potential to stop tumor cell growth and reverse immunosuppression.
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Affiliation(s)
| | - Allea Cauilan
- Department of Biology, California State University Northridge, Northridge, CA 91330, USA
| | - David Quintero
- Los Angeles Medical Facility, Los Angeles, CA 90027, USA
| | - David Bermudes
- Department of Biology, California State University Northridge, Northridge, CA 91330, USA
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Yuasa HJ. Metazoan tryptophan indole-lyase: Are they still active? Comp Biochem Physiol B Biochem Mol Biol 2023; 263:110801. [PMID: 36228898 DOI: 10.1016/j.cbpb.2022.110801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 10/03/2022] [Accepted: 10/06/2022] [Indexed: 11/06/2022]
Abstract
Tryptophan indole-lyase (TIL), also known as tryptophanase, is a pyridoxal-5'-phosphate dependent bacterial enzyme that catalyzes the reversible hydrolytic cleavage of l-tryptophan (l-Trp) to indole and ammonium pyruvate. TIL is also found in some metazoans, and they may have been acquired by horizontal gene transfer. In this study, two metazoans, Nematostella vectensis (starlet sea anemone) and Bradysia coprophila (fungus gnat) TILs were bacterially expressed and characterized. The kcat values of metazoan TILs were low, < 1/200 of the kcat of Escherichia coli TIL. By contrast, metazoan TILs showed lower Km values than the TILs of common bacteria, indicating that their affinity for l-Trp is higher than that of bacterial TILs. Analysis of a series of chimeric enzymes based on B. coprophila and bacterial TILs revealed that the low Km value of B. coprophila TIL is not accidental due to the substitution of a single residue, but is due to the cooperative effect of multiple residues. This suggests that high affinity for l-Trp was positively selected during the molecular evolution of metazoan TIL. This is the first report that metazoan TILs have low but obvious activity.
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Affiliation(s)
- Hajime Julie Yuasa
- Laboratory of Biochemistry, Department of Chemistry and Biotechnology, Faculty of Science and Technology, National University Corporation Kochi University, Kochi 780-8520, Japan.
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Production of indole and hydrogen sulfide by the oxygen-tolerant mutant strain Clostridium sp. Aeroto-AUH-JLC108 contributes to form a hypoxic microenvironment. Arch Microbiol 2022; 204:486. [PMID: 35834134 DOI: 10.1007/s00203-022-03113-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 06/25/2022] [Accepted: 06/28/2022] [Indexed: 11/02/2022]
Abstract
In this study, the oxygen-tolerant mutant strain Clostridium sp. Aeroto-AUH-JLC108 was found to produce indole when grown aerobically. The tnaA gene coding for tryptophanase responsible for the production of indole was cloned. The tnaA gene from Aeroto-AUH-JLC108 is 1677 bp and has one point mutation (C36G) compared to the original anaerobic strain AUH-JLC108. Phylogenetic analyses based on the amino acid sequence showed significant homology to that of TnaA from Flavonifractor. Furthermore, we found that the tnaA gene also exhibited cysteine desulfhydrase activity. The production of hydrogen sulfide (H2S) was accompanied by decrease in the amount of the dissolved oxygen in the culture medium. Similarly, the amount of indole produced by strain Aeroto-AUH-JLC108 obviously decreased the oxidation-reduction potential (ORP) in BHI liquid medium. The results demonstrated that production of indole and H2S helped to form a hypoxic microenvironment for strain Aeroto-AUH-JLC108 when grown aerobically.
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Mindt M, Beyraghdar Kashkooli A, Suarez-Diez M, Ferrer L, Jilg T, Bosch D, Martins Dos Santos V, Wendisch VF, Cankar K. Production of indole by Corynebacterium glutamicum microbial cell factories for flavor and fragrance applications. Microb Cell Fact 2022; 21:45. [PMID: 35331232 PMCID: PMC8944080 DOI: 10.1186/s12934-022-01771-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/01/2022] [Indexed: 02/07/2023] Open
Abstract
Background The nitrogen containing aromatic compound indole is known for its floral odor typical of jasmine blossoms. Due to its characteristic scent, it is frequently used in dairy products, tea drinks and fine fragrances. The demand for natural indole by the flavor and fragrance industry is high, yet, its abundance in essential oils isolated from plants such as jasmine and narcissus is low. Thus, there is a strong demand for a sustainable method to produce food-grade indole. Results Here, we established the biotechnological production of indole upon l-tryptophan supplementation in the bacterial host Corynebacterium glutamicum. Heterologous expression of the tryptophanase gene from E. coli enabled the conversion of supplemented l-tryptophan to indole. Engineering of the substrate import by co-expression of the native aromatic amino acid permease gene aroP increased whole-cell biotransformation of l-tryptophan to indole by two-fold. Indole production to 0.2 g L−1 was achieved upon feeding of 1 g L−1l-tryptophan in a bioreactor cultivation, while neither accumulation of side-products nor loss of indole were observed. To establish an efficient and robust production process, new tryptophanases were recruited by mining of bacterial sequence databases. This search retrieved more than 400 candidates and, upon screening of tryptophanase activity, nine new enzymes were identified as most promising. The highest production of indole in vivo in C. glutamicum was achieved based on the tryptophanase from Providencia rettgeri. Evaluation of several biological aspects identified the product toxicity as major bottleneck of this conversion. In situ product recovery was applied to sequester indole in a food-grade organic phase during the fermentation to avoid inhibition due to product accumulation. This process enabled complete conversion of l-tryptophan and an indole product titer of 5.7 g L−1 was reached. Indole partitioned to the organic phase which contained 28 g L−1 indole while no other products were observed indicating high indole purity. Conclusions The bioconversion production process established in this study provides an attractive route for sustainable indole production from tryptophan in C. glutamicum. Industrially relevant indole titers were achieved within 24 h and indole was concentrated in the organic layer as a pure product after the fermentation. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01771-y.
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Affiliation(s)
- Melanie Mindt
- Business Unit Bioscience, Wageningen Plant Research, Wageningen University & Research, Wageningen, The Netherlands.,Axxence Aromatic GmbH, Emmerich am Rhein, Germany
| | - Arman Beyraghdar Kashkooli
- Business Unit Bioscience, Wageningen Plant Research, Wageningen University & Research, Wageningen, The Netherlands
| | - Maria Suarez-Diez
- Laboratory of Systems and Synthetic Biology, Wageningen University & Research, Wageningen, The Netherlands
| | - Lenny Ferrer
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Tatjana Jilg
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Dirk Bosch
- Business Unit Bioscience, Wageningen Plant Research, Wageningen University & Research, Wageningen, The Netherlands
| | - Vitor Martins Dos Santos
- Laboratory of Systems and Synthetic Biology, Wageningen University & Research, Wageningen, The Netherlands.,Laboratory of Bioprocess Engineering, Wageningen University & Research, Wageningen, The Netherlands
| | - Volker F Wendisch
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Katarina Cankar
- Business Unit Bioscience, Wageningen Plant Research, Wageningen University & Research, Wageningen, The Netherlands.
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Boya BR, Kumar P, Lee JH, Lee J. Diversity of the Tryptophanase Gene and Its Evolutionary Implications in Living Organisms. Microorganisms 2021; 9:microorganisms9102156. [PMID: 34683477 PMCID: PMC8537960 DOI: 10.3390/microorganisms9102156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/09/2021] [Accepted: 10/12/2021] [Indexed: 12/11/2022] Open
Abstract
Tryptophanase encoded by the gene tnaA is a pyridoxal phosphate-dependent enzyme that catalyses the conversion of tryptophan to indole, which is commonly used as an intra- and interspecies signalling molecule, particularly by microbes. However, the production of indole is rare in eukaryotic organisms. A nucleotide and protein database search revealed tnaA is commonly reported in various Gram-negative bacteria, but that only a few Gram-positive bacteria and archaea possess the gene. The presence of tnaA in eukaryotes, particularly protozoans and marine organisms, demonstrates the importance of this gene in the animal kingdom. Here, we document the distribution of tnaA and its acquisition and expansion among different taxonomic groups, many of which are usually categorized as non-indole producers. This study provides an opportunity to understand the intriguing role played by tnaA, and its distribution among various types of organisms.
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Li L, Xiong Q, Zhao J, Lin X, He S, Wu N, Yao Y, Liang W, Zuo X, Ying C. Inulin-type fructan intervention restricts the increase in gut microbiome-generated indole in patients with peritoneal dialysis: a randomized crossover study. Am J Clin Nutr 2020; 111:1087-1099. [PMID: 31942927 DOI: 10.1093/ajcn/nqz337] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 12/17/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Indoxyl sulfate (IS) and p-cresyl sulfate (pCS), 2 important protein-bound uremic toxins, are independent risk factors for cardiovascular disease in patients with end-stage renal disease. Indole and p-cresol are gut microbiome-generated precursors of IS and pCS. OBJECTIVE The aim of the present study was to determine whether inulin-type fructans (ITFs) reduce the production of indole and p-cresol by altering their producing bacteria in patients with peritoneal dialysis. METHODS Patients receiving peritoneal dialysis for >3 mo without diabetes and not using antibiotics were recruited to a randomized, double-blind, placebo-controlled, crossover trial of ITF intervention over 36 wk (12-wk washout). The primary outcomes were gut microbiome, fecal indole and p-cresol, indole-producing bacteria, p-cresol-producing bacteria, and serum IS and pCS. The secondary outcomes were fecal pH, 24-h urine, and dialysis removal of IS and pCS. RESULTS Of 21 individuals randomly assigned, 15 completed the study. The daily nutrient intakes, including protein, tryptophan, and tyrosine, were isostatic during the prebiotic, washout, and placebo intervention. There were no baseline differences in the outcomes of interest between treatments. For fecal indole, its concentrations did not change significantly in either treatment. However, there was a trend toward the treatment-by-time effect (P = 0.052), with a quantitative reduction in the ITF treatment and an increase in the control. The difference in the changes between the 2 treatments was significant (-10.07 ± 7.48 μg/g vs +13.35 ± 7.66 μg/g; P = 0.040). Similar to Bacteroides thetaiotaomicron, there was a difference over time between the 2 treatments, with a significant treatment and time interaction effect (P = 0.047). There were no treatment, time, or interaction effects for fecal p-cresol, serum IS and pCS, 24-h urine, and dialysis removal of IS and pCS. CONCLUSIONS Our results suggested that ITFs restricted the increase in gut microbiome-generated indole in patients with peritoneal dialysis. This trial was registered at http://www.chictr.org.cn/showproj.aspx?proj=21228 as ChiCTR-INR-17013739.
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Affiliation(s)
- Li Li
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qingqing Xiong
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jing Zhao
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xuechun Lin
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shuiqin He
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Nannan Wu
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ying Yao
- Department of Clinical Nutrition, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wangqun Liang
- Division of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xuezhi Zuo
- Department of Clinical Nutrition, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chenjiang Ying
- Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Zhao L, Zhang H, Wang X, Han G, Ma W, Hu X, Li Y. Transcriptomic analysis of an l-threonine-producing Escherichia coli TWF001. Biotechnol Appl Biochem 2020; 67:414-429. [PMID: 31976571 DOI: 10.1002/bab.1890] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 01/21/2020] [Indexed: 01/10/2023]
Abstract
Wild-type Escherichia coli usually does not accumulate l-threonine, but E. coli strain TWF001 could produce 30.35 g/L l-threonine after 23-H fed-batch fermentation. To understand the mechanism for the high yield of l-threonine production in TWF001, transcriptomic analyses of the TWF001 cell samples collected at the logarithmic and stationary phases were performed, using the wild-type E. coli strain W3110 as the control. Compared with W3110, 1739 and 2361 genes were differentially transcribed in the logarithmic and stationary phases, respectively. Most genes related to the biosynthesis of l-threonine were significantly upregulated. Some key genes related to the NAD(P)H regeneration were upregulated. Many genes relevant to glycolysis and TCA cycle were downregulated. The key genes involved in the l-threonine degradation were downregulated. The gene rhtA encoding the l-threonine exporter was upregulated, whereas the genes sstT and tdcC encoding the l-threonine importer were downregulated. The upregulated genes in the glutamate pathway might form an amino-providing loop, which is beneficial for the high yield of l-threonine production. Many genes encoding the 30S and 50S subunits of ribosomes were also upregulated. The findings are useful for gene engineering to increase l-threonine production in E. coli.
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Affiliation(s)
- Lei Zhao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Hailing Zhang
- Department of Biological Engineering, College of Life Science, Yantai University, Shandong, 408100, China
| | - Xiaoyuan Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, China
| | - Guoqiang Han
- College of Modern Agriculture and Biological Engineering, Yangtze Normal University, Chongqing, 264005, China
| | - Wenjian Ma
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, China
| | - Xiaoqing Hu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, China
| | - Ye Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China
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Planchon M, Léger T, Spalla O, Huber G, Ferrari R. Metabolomic and proteomic investigations of impacts of titanium dioxide nanoparticles on Escherichia coli. PLoS One 2017; 12:e0178437. [PMID: 28570583 PMCID: PMC5453534 DOI: 10.1371/journal.pone.0178437] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 05/13/2017] [Indexed: 11/18/2022] Open
Abstract
In a previous study, it was demonstrated that the toxic impact of titanium dioxide nanoparticles on Escherichia coli starts at 10 ppm and is closely related to the presence of little aggregates. It was also assumed that only a part of the bacterial population is able to adapt to this stress and attempts to survive. Proteomic analyses, supported by results from metabolomics, reveal that exposure of E. coli to nano-TiO2 induces two main effects on bacterial metabolism: firstly, the up-regulation of proteins and the increase of metabolites related to energy and growth metabolism; secondly, the down-regulation of other proteins resulting in an increase of metabolites, particularly amino acids. Some proteins, e.g. chaperonin 1 or isocitrate dehydrogenase, and some metabolites, e.g. phenylalanine or valine, might be used as biomarkers of nanoparticles stress. Astonishingly, the ATP content gradually rises in relation with the nano-TiO2 concentration in the medium, indicating a dramatic release of ATP by the damaged cells. These apparently contradictory results accredit the thesis of a heterogeneity of the bacterial population. This heterogeneity is also confirmed by SEM images which show that while some bacteria are fully covered by nano-TiO2, the major part of the bacterial population remains free from nanoparticles, resulting in a difference of proteome and metabolome. The use of combined-omics has allowed to better understand the heterogeneous bacterial response to nano-TiO2 stress due to heterogeneous contacts between the protagonists under environmental conditions.
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Affiliation(s)
- Mariane Planchon
- NIMBE, CEA, CNRS, Université Paris-Saclay, CEA Saclay 91191 Gif-sur-Yvette, France
- Université Paris Diderot, Sorbonne Paris Cité, IPGP, UMR 7154, Paris Cedex 13 France
- iCEINT, International Consortium for the Environmental Implications of Nanotechnology
| | - Thibaut Léger
- Mass Spectrometry Laboratory, Institut Jacques Monod, UMR 7592, Univ Paris Diderot, CNRS, Sorbonne Paris Cité, Paris, France
| | - Olivier Spalla
- NIMBE, CEA, CNRS, Université Paris-Saclay, CEA Saclay 91191 Gif-sur-Yvette, France
- iCEINT, International Consortium for the Environmental Implications of Nanotechnology
| | - Gaspard Huber
- NIMBE, CEA, CNRS, Université Paris-Saclay, CEA Saclay 91191 Gif-sur-Yvette, France
- * E-mail: (GH); (RF)
| | - Roselyne Ferrari
- Université Paris Diderot, Sorbonne Paris Cité, IPGP, UMR 7154, Paris Cedex 13 France
- Université Paris Diderot, Sorbonne Paris Cité, LIED, UMR 8236, Paris, France
- * E-mail: (GH); (RF)
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