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Warneke R, Herzberg C, Weiß M, Schramm T, Hertel D, Link H, Stülke J. DarA-the central processing unit for the integration of osmotic with potassium and amino acid homeostasis in Bacillus subtilis. J Bacteriol 2024:e0019024. [PMID: 38832794 DOI: 10.1128/jb.00190-24] [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: 05/01/2024] [Accepted: 05/08/2024] [Indexed: 06/05/2024] Open
Abstract
Cyclic di-adenosine monophosphate (c-di-AMP) is a second messenger involved in diverse metabolic processes including osmolyte uptake, cell wall homeostasis, as well as antibiotic and heat resistance. This study investigates the role of the c-di-AMP receptor protein DarA in the osmotic stress response in Bacillus subtilis. Through a series of experiments, we demonstrate that DarA plays a central role in the cellular response to osmotic fluctuations. Our findings show that DarA becomes essential under extreme potassium limitation as well as upon salt stress, highlighting its significance in mediating osmotic stress adaptation. Suppressor screens with darA mutants reveal compensatory mechanisms involving the accumulation of osmoprotectants, particularly potassium and citrulline. Mutations affecting various metabolic pathways, including the citric acid cycle as well as glutamate and arginine biosynthesis, indicate a complex interplay between the osmotic stress response and metabolic regulation. In addition, the growth defects of the darA mutant during potassium starvation and salt stress in a strain lacking the high-affinity potassium uptake systems KimA and KtrAB can be rescued by increased affinity of the remaining potassium channel KtrCD or by increased expression of ktrD, thus resulting in increased potassium uptake. Finally, the darA mutant can respond to salt stress by the increased expression of MleN , which can export sodium ions.IMPORTANCEEnvironmental bacteria are exposed to rapidly changing osmotic conditions making an effective adaptation to these changes crucial for the survival of the cells. In Gram-positive bacteria, the second messenger cyclic di-AMP plays a key role in this adaptation by controlling (i) the influx of physiologically compatible organic osmolytes and (ii) the biosynthesis of such osmolytes. In several bacteria, cyclic di-adenosine monophosphate (c-di-AMP) can bind to a signal transduction protein, called DarA, in Bacillus subtilis. So far, no function for DarA has been discovered in any organism. We have identified osmotically challenging conditions that make DarA essential and have identified suppressor mutations that help the bacteria to adapt to those conditions. Our results indicate that DarA is a central component in the integration of osmotic stress with the synthesis of compatible amino acid osmolytes and with the homeostasis of potassium, the first response to osmotic stress.
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Affiliation(s)
- Robert Warneke
- Department of General Microbiology, GZMB, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Christina Herzberg
- Department of General Microbiology, GZMB, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Martin Weiß
- Department of General Microbiology, GZMB, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Thorben Schramm
- Interfaculty Institute for Microbiology and Infection Medicine, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Dietrich Hertel
- Department of Plant Ecology and Ecosystems Research, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Hannes Link
- Interfaculty Institute for Microbiology and Infection Medicine, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Jörg Stülke
- Interfaculty Institute for Microbiology and Infection Medicine, Eberhard Karls Universität Tübingen, Tübingen, Germany
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Wang K, Wang Y, Gu L, Yu J, Liu Q, Zhang R, Liang G, Chen H, Gu F, Liu H, Jiao X, Zhang Y. Characterization of Probiotic Properties and Whole-Genome Analysis of Lactobacillus johnsonii N5 and N7 Isolated from Swine. Microorganisms 2024; 12:672. [PMID: 38674616 PMCID: PMC11052194 DOI: 10.3390/microorganisms12040672] [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: 02/21/2024] [Revised: 03/22/2024] [Accepted: 03/25/2024] [Indexed: 04/28/2024] Open
Abstract
In our previous microbiome profiling analysis, Lactobacillus (L.) johnsonii was suggested to contribute to resistance against chronic heat stress-induced diarrhea in weaned piglets. Forty-nine L. johnsonii strains were isolated from these heat stress-resistant piglets, and their probiotic properties were assessed. Strains N5 and N7 exhibited a high survival rate in acidic and bile environments, along with an antagonistic effect against Salmonella. To identify genes potentially involved in these observed probiotic properties, the complete genome sequences of N5 and N7 were determined using a combination of Illumina and nanopore sequencing. The genomes of strains N5 and N7 were found to be highly conserved, with two N5-specific and four N7-specific genes identified. Multiple genes involved in gastrointestinal environment adaptation and probiotic properties, including acidic and bile stress tolerance, anti-inflammation, CAZymes, and utilization and biosynthesis of carbohydrate compounds, were identified in both genomes. Comparative genome analysis of the two genomes and 17 available complete L. johnsonii genomes revealed 101 genes specifically harbored by strains N5 and N7, several of which were implicated in potential probiotic properties. Overall, this study provides novel insights into the genetic basis of niche adaptation and probiotic properties, as well as the genome diversity of L. johnsonii.
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Affiliation(s)
- Kun Wang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; (K.W.); (Y.W.); (L.G.); (J.Y.); (Q.L.); (R.Z.); (G.L.); (H.C.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Yu Wang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; (K.W.); (Y.W.); (L.G.); (J.Y.); (Q.L.); (R.Z.); (G.L.); (H.C.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Lifang Gu
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; (K.W.); (Y.W.); (L.G.); (J.Y.); (Q.L.); (R.Z.); (G.L.); (H.C.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Jinyan Yu
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; (K.W.); (Y.W.); (L.G.); (J.Y.); (Q.L.); (R.Z.); (G.L.); (H.C.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Qianwen Liu
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; (K.W.); (Y.W.); (L.G.); (J.Y.); (Q.L.); (R.Z.); (G.L.); (H.C.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Ruiqi Zhang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; (K.W.); (Y.W.); (L.G.); (J.Y.); (Q.L.); (R.Z.); (G.L.); (H.C.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Guixin Liang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; (K.W.); (Y.W.); (L.G.); (J.Y.); (Q.L.); (R.Z.); (G.L.); (H.C.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Huan Chen
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; (K.W.); (Y.W.); (L.G.); (J.Y.); (Q.L.); (R.Z.); (G.L.); (H.C.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Fang Gu
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
| | - Haoyu Liu
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China
| | - Xin’an Jiao
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; (K.W.); (Y.W.); (L.G.); (J.Y.); (Q.L.); (R.Z.); (G.L.); (H.C.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Yunzeng Zhang
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; (K.W.); (Y.W.); (L.G.); (J.Y.); (Q.L.); (R.Z.); (G.L.); (H.C.)
- Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; (F.G.); (H.L.)
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
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Lailaja VP, Hari V, Sumithra TG, Anusree VN, Suresh G, Sanil NK, Sharma S R K, Gopalakrishnan A. In vitro and in silico analysis unravelled clinically desirable attributes of Bacillus altitudinis L-asparaginase. J Appl Microbiol 2024; 135:lxae062. [PMID: 38467390 DOI: 10.1093/jambio/lxae062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 03/04/2024] [Accepted: 03/07/2024] [Indexed: 03/13/2024]
Abstract
AIMS To identify a marine L-asparaginase with clinically desirable attributes and characterize the shortlisted candidate through in silico tools. METHODS AND RESULTS Marine bacterial strains (number = 105) isolated from marine crabs were evaluated through a stepwise strategy incorporating the crucial attributes for therapeutic safety. The results demonstrated the potential of eight bacterial species for extracellular L-asparaginase production. However, only one isolate (Bacillus altitudinis CMFRI/Bal-2) showed clinically desirable attributes, viz. extracellular production, type-II nature, lack of concurrent L-glutaminase and urease activities, and presence of ansZ (functional gene for clinical type). The enzyme production was 22.55 ± 0.5 µM/mg protein/min within 24 h without optimization. The enzyme also showed good activity and stability in pH 7-8 and temperature 37°C, predicting the functioning inside the human body. The Michealis-Menten constant (Km) was 14.75 µM. Detailed in silico analysis based on functional gene authenticating the results of in vitro characterization and predicted the nonallergenic characteristic of the candidate. Docking results proved the higher affinity of the shortlisted candidate to L-asparagine than L-glutamine and urea. CONCLUSION Comprehensively, the study highlighted B. altitudinis type II asparaginase as a competent candidate for further research on clinically safe asparaginases.
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Affiliation(s)
- V P Lailaja
- Marine Biotechnology, Fish Nutrition and Health Division, ICAR-Central Marine Fisheries Research Institute (CMFRI), Ernakulam Kochi 682018, Kerala, India
| | - Vishnu Hari
- Marine Biotechnology, Fish Nutrition and Health Division, ICAR-Central Marine Fisheries Research Institute (CMFRI), Ernakulam Kochi 682018, Kerala, India
| | - T G Sumithra
- Marine Biotechnology, Fish Nutrition and Health Division, ICAR-Central Marine Fisheries Research Institute (CMFRI), Ernakulam Kochi 682018, Kerala, India
| | - V N Anusree
- Marine Biotechnology, Fish Nutrition and Health Division, ICAR-Central Marine Fisheries Research Institute (CMFRI), Ernakulam Kochi 682018, Kerala, India
| | - Gayathri Suresh
- Marine Biotechnology, Fish Nutrition and Health Division, ICAR-Central Marine Fisheries Research Institute (CMFRI), Ernakulam Kochi 682018, Kerala, India
- Cochin University of Science and Technology, Kochi 682022, Kerala, India
| | - N K Sanil
- Marine Biotechnology, Fish Nutrition and Health Division, ICAR-Central Marine Fisheries Research Institute (CMFRI), Ernakulam Kochi 682018, Kerala, India
| | - Krupesha Sharma S R
- Marine Biotechnology, Fish Nutrition and Health Division, ICAR-Central Marine Fisheries Research Institute (CMFRI), Ernakulam Kochi 682018, Kerala, India
| | - A Gopalakrishnan
- Marine Biotechnology, Fish Nutrition and Health Division, ICAR-Central Marine Fisheries Research Institute (CMFRI), Ernakulam Kochi 682018, Kerala, India
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Mardoukhi MSY, Rapp J, Irisarri I, Gunka K, Link H, Marienhagen J, de Vries J, Stülke J, Commichau FM. Metabolic rewiring enables ammonium assimilation via a non-canonical fumarate-based pathway. Microb Biotechnol 2024; 17:e14429. [PMID: 38483038 PMCID: PMC10938345 DOI: 10.1111/1751-7915.14429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/16/2024] [Accepted: 02/09/2024] [Indexed: 03/17/2024] Open
Abstract
Glutamate serves as the major cellular amino group donor. In Bacillus subtilis, glutamate is synthesized by the combined action of the glutamine synthetase and the glutamate synthase (GOGAT). The glutamate dehydrogenases are devoted to glutamate degradation in vivo. To keep the cellular glutamate concentration high, the genes and the encoded enzymes involved in glutamate biosynthesis and degradation need to be tightly regulated depending on the available carbon and nitrogen sources. Serendipitously, we found that the inactivation of the ansR and citG genes encoding the repressor of the ansAB genes and the fumarase, respectively, enables the GOGAT-deficient B. subtilis mutant to synthesize glutamate via a non-canonical fumarate-based ammonium assimilation pathway. We also show that the de-repression of the ansAB genes is sufficient to restore aspartate prototrophy of an aspB aspartate transaminase mutant. Moreover, in the presence of arginine, B. subtilis mutants lacking fumarase activity show a growth defect that can be relieved by aspB overexpression, by reducing arginine uptake and by decreasing the metabolic flux through the TCA cycle.
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Affiliation(s)
| | - Johanna Rapp
- Interfaculty Institute for Microbiology and Infection Medicine TübingenUniversity of TübingenTübingenGermany
| | - Iker Irisarri
- Department of Applied Bioinformatics, Institute of Microbiology and Genetics, GZMBGeorg‐August‐University GöttingenGöttingenGermany
- Campus Institute Data ScienceUniversity of GöttingenGöttingenGermany
| | - Katrin Gunka
- Department of General Microbiology, Institute for Microbiology and Genetics, GZMBGeorg‐August‐University GöttingenGöttingenGermany
| | - Hannes Link
- Interfaculty Institute for Microbiology and Infection Medicine TübingenUniversity of TübingenTübingenGermany
| | - Jan Marienhagen
- Institute of Bio‐ and Geosciences, IBG‐1: BiotechnologyForschungszentrum JülichJülichGermany
- Institut of BiotechnologyRWTH Aachen UniversityAachenGermany
| | - Jan de Vries
- Department of Applied Bioinformatics, Institute of Microbiology and Genetics, GZMBGeorg‐August‐University GöttingenGöttingenGermany
- Campus Institute Data ScienceUniversity of GöttingenGöttingenGermany
| | - Jörg Stülke
- Department of General Microbiology, Institute for Microbiology and Genetics, GZMBGeorg‐August‐University GöttingenGöttingenGermany
| | - Fabian M. Commichau
- FG Molecular Microbiology, Institute for BiologyUniversity of HohenheimStuttgartGermany
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Meißner J, Königshof M, Wrede K, Warneke R, Mardoukhi MSY, Commichau FM, Stülke J. Control of asparagine homeostasis in Bacillus subtilis: identification of promiscuous amino acid importers and exporters. J Bacteriol 2024; 206:e0042023. [PMID: 38193659 PMCID: PMC10882977 DOI: 10.1128/jb.00420-23] [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: 12/07/2023] [Accepted: 12/08/2023] [Indexed: 01/10/2024] Open
Abstract
The Gram-positive model bacterium B. subtilis is able to import all proteinogenic amino acids from the environment as well as to synthesize them. However, the players involved in the acquisition of asparagine have not yet been identified for this bacterium. In this work, we used d-asparagine as a toxic analog of l-asparagine to identify asparagine transporters. This revealed that d- but not l-asparagine is taken up by the malate/lactate antiporter MleN. Specific strains that are sensitive to the presence of l-asparagine due to the lack of the second messenger cyclic di-AMP or due to the intracellular accumulation of this amino acid were used to isolate and characterize suppressor mutants that were resistant to the presence of otherwise growth-inhibiting concentrations of l-asparagine. These screens identified the broad-spectrum amino acid importers AimA and BcaP as responsible for the acquisition of l-asparagine. The amino acid exporter AzlCD allows detoxification of l-asparagine in addition to 4-azaleucine and histidine. This work supports the idea that amino acids are often transported by promiscuous importers and exporters. However, our work also shows that even stereo-enantiomeric amino acids do not necessarily use the same transport systems.IMPORTANCETransport of amino acid is a poorly studied function in many bacteria, including the model organism Bacillus subtilis. The identification of transporters is hampered by the redundancy of transport systems for most amino acids as well as by the poor specificity of the transporters. Here, we apply several strategies to use the growth-inhibitive effect of many amino acids under defined conditions to isolate suppressor mutants that exhibit either reduced uptake or enhanced export of asparagine, resulting in the identification of uptake and export systems for l-asparagine. The approaches used here may be useful for the identification of transporters for other amino acids both in B. subtilis and in other bacteria.
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Affiliation(s)
- Janek Meißner
- Department of General Microbiology, Institute for Microbiology & Genetics, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | - Manuel Königshof
- Department of General Microbiology, Institute for Microbiology & Genetics, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | - Katrin Wrede
- Department of General Microbiology, Institute for Microbiology & Genetics, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | - Robert Warneke
- Department of General Microbiology, Institute for Microbiology & Genetics, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | | | - Fabian M. Commichau
- FG Molecular Microbiology, Institute for Biology, University of Hohenheim, Stuttgart, Germany
| | - Jörg Stülke
- Department of General Microbiology, Institute for Microbiology & Genetics, GZMB, Georg-August-University Göttingen, Göttingen, Germany
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Arredondo-Nuñez A, Monteiro G, Flores-Fernández CN, Antenucci L, Permi P, Zavaleta AI. Characterization of a Type II L-Asparaginase from the Halotolerant Bacillus subtilis CH11. Life (Basel) 2023; 13:2145. [PMID: 38004285 PMCID: PMC10672034 DOI: 10.3390/life13112145] [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: 09/29/2023] [Revised: 10/28/2023] [Accepted: 10/30/2023] [Indexed: 11/26/2023] Open
Abstract
L-asparaginases from bacterial sources have been used in antineoplastic treatments and the food industry. A type II L-asparaginase encoded by the N-truncated gene ansZP21 of halotolerant Bacillus subtilis CH11 isolated from Chilca salterns in Peru was expressed using a heterologous system in Escherichia coli BL21 (DE3)pLysS. The recombinant protein was purified using one-step nickel affinity chromatography and exhibited an activity of 234.38 U mg-1 and a maximum catalytic activity at pH 9.0 and 60 °C. The enzyme showed a homotetrameric form with an estimated molecular weight of 155 kDa through gel filtration chromatography. The enzyme half-life at 60 °C was 3 h 48 min, and L-asparaginase retained 50% of its initial activity for 24 h at 37 °C. The activity was considerably enhanced by KCl, CaCl2, MgCl2, mercaptoethanol, and DL-dithiothreitol (p-value < 0.01). Moreover, the Vmax and Km were 145.2 µmol mL-1 min-1 and 4.75 mM, respectively. These findings evidence a promising novel type II L-asparaginase for future industrial applications.
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Affiliation(s)
- Annsy Arredondo-Nuñez
- Laboratorio de Biología Molecular, Facultad de Farmacia y Bioquímica, Universidad Nacional Mayor de San Marcos, Lima 01, Peru;
| | - Gisele Monteiro
- Department of Pharmaceutical and Biochemical Technology, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, Brazil;
| | - Carol N. Flores-Fernández
- Laboratorio de Biología Molecular, Facultad de Farmacia y Bioquímica, Universidad Nacional Mayor de San Marcos, Lima 01, Peru;
| | - Lina Antenucci
- Department of Biological and Environmental Science, Nanoscience Center, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyvaskyla, Finland; (L.A.); (P.P.)
| | - Perttu Permi
- Department of Biological and Environmental Science, Nanoscience Center, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyvaskyla, Finland; (L.A.); (P.P.)
- Department of Chemistry, Nanoscience Center, University of Jyvaskyla, P.O. Box 35, FI-40014 Jyvaskyla, Finland
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, P.O. Box 65, FI-00014 Helsinki, Finland
| | - Amparo Iris Zavaleta
- Laboratorio de Biología Molecular, Facultad de Farmacia y Bioquímica, Universidad Nacional Mayor de San Marcos, Lima 01, Peru;
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Toyoda K, Sugaya R, Domon A, Suda M, Hiraga K, Inui M. Identification and Molecular Characterization of the Operon Required for L-Asparagine Utilization in Corynebacterium glutamicum. Microorganisms 2022; 10:1002. [PMID: 35630445 PMCID: PMC9145765 DOI: 10.3390/microorganisms10051002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 04/30/2022] [Accepted: 05/07/2022] [Indexed: 11/25/2022] Open
Abstract
Understanding the metabolic pathways of amino acids and their regulation is important for the rational metabolic engineering of amino acid production. The catabolic pathways of L-asparagine and L-aspartate are composed of transporters for amino acid uptake and asparaginase and aspartase, which are involved in the sequential deamination to fumarate. However, knowledge of the catabolic genes for asparagine in bacteria of the Actinobacteria class has been limited. In this study, we identified and characterized the ans operon required for L-Asn catabolism in Corynebacterium glutamicum R. The operon consisted of genes encoding a transcriptional regulator (AnsR), asparaginase (AnsA2), aspartase (AspA2), and permease (AnsP). The enzymes and permease encoded in the operon were shown to be essential for L-Asn utilization, but another asparaginase, AnsA1, and aspartase, AspA1, were not essential. Expression analysis revealed that the operon was induced in response to extracellular L-Asn and was transcribed as a leaderless mRNA. The DNA-binding assay demonstrated that AnsR acted as a transcriptional repressor of the operon by binding to the inverted repeat at its 5'-end region. The AnsR binding was inhibited by L-Asn. This study provides insights into the functions and regulatory mechanisms of similar operon-like clusters in related bacteria.
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Affiliation(s)
- Koichi Toyoda
- Research Institute of Innovative Technology for the Earth (RITE), 9-2 Kizugawadai, Kizugawa 619-0292, Japan; (K.T.); (M.S.); (K.H.)
| | - Riki Sugaya
- Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma 630-0192, Japan; (R.S.); (A.D.)
| | - Akihiro Domon
- Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma 630-0192, Japan; (R.S.); (A.D.)
| | - Masako Suda
- Research Institute of Innovative Technology for the Earth (RITE), 9-2 Kizugawadai, Kizugawa 619-0292, Japan; (K.T.); (M.S.); (K.H.)
| | - Kazumi Hiraga
- Research Institute of Innovative Technology for the Earth (RITE), 9-2 Kizugawadai, Kizugawa 619-0292, Japan; (K.T.); (M.S.); (K.H.)
| | - Masayuki Inui
- Research Institute of Innovative Technology for the Earth (RITE), 9-2 Kizugawadai, Kizugawa 619-0292, Japan; (K.T.); (M.S.); (K.H.)
- Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma 630-0192, Japan; (R.S.); (A.D.)
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Bremer E, Hoffmann T, Dempwolff F, Bedrunka P, Bange G. The many faces of the unusual biofilm activator RemA. Bioessays 2022; 44:e2200009. [PMID: 35289951 DOI: 10.1002/bies.202200009] [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: 01/11/2022] [Revised: 02/28/2022] [Accepted: 03/02/2022] [Indexed: 11/08/2022]
Abstract
Biofilms can be viewed as tissue-like structures in which microorganisms are organized in a spatial and functional sophisticated manner. Biofilm formation requires the orchestration of a highly integrated network of regulatory proteins to establish cell differentiation and production of a complex extracellular matrix. Here, we discuss the role of the essential Bacillus subtilis biofilm activator RemA. Despite intense research on biofilms, RemA is a largely underappreciated regulatory protein. RemA forms donut-shaped octamers with the potential to assemble into dimeric superstructures. The presumed DNA-binding mode suggests that RemA organizes its target DNA into nucleosome-like structures, which are the basis for its role as transcriptional activator. We discuss how RemA affects gene expression in the context of biofilm formation, and its regulatory interplay with established components of the biofilm regulatory network, such as SinR, SinI, SlrR, and SlrA. We emphasize the additional role of RemA played in nitrogen metabolism and osmotic-stress adjustment.
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Affiliation(s)
- Erhard Bremer
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| | - Tamara Hoffmann
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| | - Felix Dempwolff
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| | - Patricia Bedrunka
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| | - Gert Bange
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany.,Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
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9
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Castro D, Marques ASC, Almeida MR, de Paiva GB, Bento HBS, Pedrolli DB, Freire MG, Tavares APM, Santos-Ebinuma VC. L-asparaginase production review: bioprocess design and biochemical characteristics. Appl Microbiol Biotechnol 2021; 105:4515-4534. [PMID: 34059941 DOI: 10.1007/s00253-021-11359-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/06/2021] [Accepted: 05/16/2021] [Indexed: 12/17/2022]
Abstract
In the past decades, the production of biopharmaceuticals has gained high interest due to its great sensitivity, specificity, and lower risk of negative effects to patients. Biopharmaceuticals are mostly therapeutic recombinant proteins produced through biotechnological processes. In this context, L-asparaginase (L-asparagine amidohydrolase, L-ASNase (E.C. 3.5.1.1)) is a therapeutic enzyme that has been abundantly studied by researchers due to its antineoplastic properties. As a biopharmaceutical, L-ASNase has been used in the treatment of acute lymphoblastic leukemia (ALL), acute myeloblastic leukemia (AML), and other lymphoid malignancies, in combination with other drugs. Besides its application as a biopharmaceutical, this enzyme is widely used in food processing industries as an acrylamide mitigation agent and as a biosensor for the detection of L-asparagine in physiological fluids at nano-levels. The great demand for L-ASNase is supplied by recombinant enzymes from Escherichia coli and Erwinia chrysanthemi. However, production processes are associated to low yields and proteins associated to immunogenicity problems, which leads to the search for a better enzyme source. Considering the L-ASNase pharmacological and food importance, this review provides an overview of the current biotechnological developments in L-ASNase production and biochemical characterization aiming to improve the knowledge about its production. KEY POINTS: • Microbial enzyme applications as biopharmaceutical and in food industry • Biosynthesis process: from the microorganism to bioreactor technology • Enzyme activity and kinetic properties: crucial for the final application.
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Affiliation(s)
- Daniel Castro
- CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Ana Sofia C Marques
- CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Mafalda R Almeida
- CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Gabriela B de Paiva
- Department of Engineering Bioprocess and Biotechnology, School of Pharmaceutical Sciences, UNESP - São Paulo State University, Araraquara, Brazil
| | - Heitor B S Bento
- Department of Engineering Bioprocess and Biotechnology, School of Pharmaceutical Sciences, UNESP - São Paulo State University, Araraquara, Brazil
| | - Danielle B Pedrolli
- Department of Engineering Bioprocess and Biotechnology, School of Pharmaceutical Sciences, UNESP - São Paulo State University, Araraquara, Brazil
| | - Mara G Freire
- CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Ana P M Tavares
- CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal.
| | - Valéria C Santos-Ebinuma
- Department of Engineering Bioprocess and Biotechnology, School of Pharmaceutical Sciences, UNESP - São Paulo State University, Araraquara, Brazil.
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10
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Eckstein S, Brehm J, Seidel M, Lechtenfeld M, Heermann R. Two novel XRE-like transcriptional regulators control phenotypic heterogeneity in Photorhabdus luminescens cell populations. BMC Microbiol 2021; 21:63. [PMID: 33627070 PMCID: PMC7905540 DOI: 10.1186/s12866-021-02116-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 01/25/2021] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND The insect pathogenic bacterium Photorhabdus luminescens exists in two phenotypically different forms, designated as primary (1°) and secondary (2°) cells. Upon yet unknown environmental stimuli up to 50% of the 1° cells convert to 2° cells. Among others, one important difference between the phenotypic forms is that 2° cells are unable to live in symbiosis with their partner nematodes, and therefore are not able to re-associate with them. As 100% switching of 1° to 2° cells of the population would lead to a break-down of the bacteria's life cycle the switching process must be tightly controlled. However, the regulation mechanism of phenotypic switching is still puzzling. RESULTS Here we describe two novel XRE family transcriptional regulators, XreR1 and XreR2, that play a major role in the phenotypic switching process of P. luminescens. Deletion of xreR1 in 1° or xreR2 in 2° cells as well as insertion of extra copies of xreR1 into 2° or xreR2 into 1° cells, respectively, induced the opposite phenotype in either 1° or 2° cells. Furthermore, both regulators specifically bind to different promoter regions putatively fulfilling a positive autoregulation. We found initial evidence that XreR1 and XreR2 constitute an epigenetic switch, whereby XreR1 represses xreR2 expression and XreR2 self-reinforces its own gene by binding to XreR1. CONCLUSION Regulation of gene expression by the two novel XRE-type regulators XreR1 and XreR2 as well as their interplay represents a major regulatory process in phenotypic switching of P. luminescens. A fine-tuning balance between both regulators might therefore define the fate of single cells to convert from the 1° to the 2° phenotype.
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Affiliation(s)
- Simone Eckstein
- Johannes-Gutenberg-Universität Mainz, Institut für Molekulare Physiologie, Biozentrum II, Mikrobiologie und Weinforschung, Hanns-Dieter-Hüsch-Weg 17, 55128, Mainz, Germany.,Ludwig-Maximilians-Universität München, Biozentrum, Bereich Mikrobiologie, Martinsried, Germany
| | - Jannis Brehm
- Johannes-Gutenberg-Universität Mainz, Institut für Molekulare Physiologie, Biozentrum II, Mikrobiologie und Weinforschung, Hanns-Dieter-Hüsch-Weg 17, 55128, Mainz, Germany
| | - Michael Seidel
- Ludwig-Maximilians-Universität München, Biozentrum, Bereich Mikrobiologie, Martinsried, Germany
| | - Mats Lechtenfeld
- Johannes-Gutenberg-Universität Mainz, Institut für Molekulare Physiologie, Biozentrum II, Mikrobiologie und Weinforschung, Hanns-Dieter-Hüsch-Weg 17, 55128, Mainz, Germany
| | - Ralf Heermann
- Johannes-Gutenberg-Universität Mainz, Institut für Molekulare Physiologie, Biozentrum II, Mikrobiologie und Weinforschung, Hanns-Dieter-Hüsch-Weg 17, 55128, Mainz, Germany.
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11
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Feng Y, Liu S, Pang C, Gao H, Wang M, Du G. Improvement of catalytic efficiency and thermal stability of l-asparaginase from Bacillus subtilis 168 through reducing the flexibility of the highly flexible loop at N-terminus. Process Biochem 2019. [DOI: 10.1016/j.procbio.2019.01.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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12
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L-asparaginase – A promising biocatalyst for industrial and clinical applications. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2018.11.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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13
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Isolation and Characterization of Thermophilic Enzymes Producing Microorganisms for Potential Therapeutic and Industrial Use. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2018. [DOI: 10.22207/jpam.12.4.02] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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14
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Shakambari G, Sameer Kumar R, Ashokkumar B, Ganesh V, Vasantha VS, Varalakshmi P. Cloning and expression of L-asparaginase from Bacillus tequilensis PV9W and therapeutic efficacy of Solid Lipid Particle formulations against cancer. Sci Rep 2018; 8:18013. [PMID: 30573733 PMCID: PMC6301963 DOI: 10.1038/s41598-018-36161-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 11/09/2018] [Indexed: 11/12/2022] Open
Abstract
L-asparaginase, a therapeutic involved in cancer therapy, from Bacillus tequilensis PV9W (ansA gene) was cloned and over expressed in Escherichia coli BL21 (DE3), achieved the aim of maximizing the yield of the recombinant enzyme (6.02 ± 1.77 IU/mL) within 12 h. The native L-asparaginase of B. tequilensis PV9W was encapsulated using solid lipid particles by hot lipid emulsion method, which is reported for first time in this study. Subsequently, the lipid encapsulated L-asparaginase (LPE) was characterized by SEM, UV-Vis spectroscopy, FT-IR, SDS-PAGE and its thermo stability was also analyzed by TGA. Further characterization of LPE revealed that enzyme was highly stable for 25 days when stored at 25 °C, showed high pH (9) tolerance and longer trypsin half-life (120 min). In addition, the cytotoxic ability of LPE on HeLa cells was highly enhanced compared to the native L-asparaginase from Bacillus tequilensis PV9W. Moreover, better kinetic velocity and lower Km values of LPE aided to detect L-asparagine in cell extracts by Differential Pulse Voltammetry (DPV) method. The LPE preparation also showed least immunogenic reaction when tested on normal macrophage cell lines. This LPE preparation might thus pave way for efficient drug delivery and enhancing the stability of L-asparaginase for its therapeutic applications.
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Affiliation(s)
- Ganeshan Shakambari
- Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai, Tamil Nadu, 625021, India
| | - Rai Sameer Kumar
- Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai, Tamil Nadu, 625021, India
| | - Balasubramaniem Ashokkumar
- Department of Genetic Engineering, School of Biotechnology, Madurai Kamaraj University, Madurai, Tamil Nadu, 625021, India
| | - Venkatachalam Ganesh
- Electrodics and Electrocatalysis (EEC) Division, CSIR - Central Electrochemical Research Institute, (CSIR - CECRI), Karaikudi, Tamilnadu, 630003, India
| | - Vairathevar Sivasamy Vasantha
- Department of Natural Products Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai, Tamil Nadu, 625021, India
| | - Perumal Varalakshmi
- Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai, Tamil Nadu, 625021, India.
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15
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Zhao H, Roistacher DM, Helmann JD. Aspartate deficiency limits peptidoglycan synthesis and sensitizes cells to antibiotics targeting cell wall synthesis in Bacillus subtilis. Mol Microbiol 2018; 109:826-844. [PMID: 29995990 DOI: 10.1111/mmi.14078] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 07/02/2018] [Accepted: 07/05/2018] [Indexed: 12/31/2022]
Abstract
Peptidoglycan synthesis is an important target for antibiotics and relies on intermediates derived from central metabolism. As a result, alterations of metabolism may affect antibiotic sensitivity. An aspB mutant is auxotrophic for aspartate (Asp) and asparagine (Asn) and lyses when grown in Difco sporulation medium (DSM), but not in LB medium. Genetic and physiological studies, supported by amino acid analysis, reveal that cell lysis in DSM results from Asp limitation due to a relatively low Asp and high glutamate (Glu) concentrations, with Glu functioning as a competitive inhibitor of Asp uptake by the major Glu/Asp transporter GltT. Lysis can be specifically suppressed by supplementation with 2,6-diaminopimelate (DAP), which is imported by two different cystine uptake systems. These studies suggest that aspartate limitation depletes the peptidoglycan precursor meso-2,6-diaminopimelate (mDAP), inhibits peptidoglycan synthesis, upregulates the cell envelope stress response mediated by σM and eventually leads to cell lysis. Aspartate limitation sensitizes cells to antibiotics targeting late steps of PG synthesis, but not steps prior to the addition of mDAP into the pentapeptide sidechain. This work highlights the ability of perturbations of central metabolism to sensitize cells to peptidoglycan synthesis inhibitors.
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Affiliation(s)
- Heng Zhao
- Department of Microbiology, Cornell University, Ithaca, NY, USA
| | | | - John D Helmann
- Department of Microbiology, Cornell University, Ithaca, NY, USA
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16
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Fujita K, Kunito T, Matsushita J, Nakamura K, Moro H, Yoshida S, Toda H, Otsuka S, Nagaoka K. Nitrogen supply rate regulates microbial resource allocation for synthesis of nitrogen-acquiring enzymes. PLoS One 2018; 13:e0202086. [PMID: 30106996 PMCID: PMC6091965 DOI: 10.1371/journal.pone.0202086] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Accepted: 07/29/2018] [Indexed: 11/19/2022] Open
Abstract
Although microorganisms will preferentially allocate resources to synthesis of nitrogen (N)-acquiring enzymes when soil N availability is low according to the resource allocation model for extracellular enzyme synthesis, a robust link between microbial N-acquiring enzyme activity and soil N concentration has not been reported. To verify this link, we measured several indices of soil N availability and enzyme activity of four N-acquiring enzymes [N-acetyl-β-glucosaminidase (NAG), protease (PR), urease (UR), and L-asparaginase (LA)] and a carbon (C)-acquiring enzyme [β-D-glucosidase (BG)] in arable and forest soils. Although the ratios of NAG/BG and PR/BG were not significantly related with indices of soil N availability, ratios of LA/BG and UR/BG were strongly and negatively related with potentially mineralizable N estimated by aerobic incubation but not with pools of labile inorganic N and organic N. These results suggest that microorganisms might allocate their resources to LA and UR synthesis in response to N supply rate rather than the size of the easily available N pools. It was also suggested that the underlying mechanism for synthesis was different between these N-acquiring enzymes in soil microorganisms: microbial LA and UR were primarily synthesized to acquire N, whereas NAG and PR syntheses were regulated not only by N availability but also by other factors.
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Affiliation(s)
- Kazuki Fujita
- Department of Environmental Sciences, Faculty of Science, Shinshu University, Matsumoto, Japan
| | - Takashi Kunito
- Department of Environmental Sciences, Faculty of Science, Shinshu University, Matsumoto, Japan
- * E-mail:
| | - Junko Matsushita
- Department of Environmental Sciences, Faculty of Science, Shinshu University, Matsumoto, Japan
| | - Kaori Nakamura
- Department of Environmental Sciences, Faculty of Science, Shinshu University, Matsumoto, Japan
| | - Hitoshi Moro
- Department of Environmental Sciences, Faculty of Science, Shinshu University, Matsumoto, Japan
| | - Seishi Yoshida
- Nagano Prefecture Vegetable and Ornamental Crops Experiment Station, Shiojiri, Japan
| | - Hideshige Toda
- Department of Environmental Sciences, Faculty of Science, Shinshu University, Matsumoto, Japan
| | - Shigeto Otsuka
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Kazunari Nagaoka
- Central Region Agricultural Research Center, NARO, Tsukuba, Japan
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17
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Izadpanah Qeshmi F, Homaei A, Fernandes P, Javadpour S. Marine microbial L-asparaginase: Biochemistry, molecular approaches and applications in tumor therapy and in food industry. Microbiol Res 2018; 208:99-112. [PMID: 29551216 DOI: 10.1016/j.micres.2018.01.011] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 01/23/2018] [Accepted: 01/28/2018] [Indexed: 10/18/2022]
Abstract
The marine environment is a rich source of biological and chemical diversity. It covers more than 70% of the Earth's surface and features a wide diversity of habitats, often displaying extreme conditions, where marine organisms thrive, offering a vast pool for microorganisms and enzymes. Given the dissimilarity between marine and terrestrial habitats, enzymes and microorganisms, either novel or with different and appealing features as compared to terrestrial counterparts, may be identified and isolated. L-asparaginase (E.C. 3.5.1.1), is among the relevant enzymes that can be obtained from marine sources. This amidohydrolase acts on L-asparagine and produce L-aspartate and ammonia, accordingly it has an acknowledged chemotherapeutic application, namely in acute lymphoblastic leukemia. Moreover, L-asparaginase is also of interest in the food industry as it prevents acrylamide formation. Terrestrial organisms have been largely tapped for L-asparaginases, but most failed to comply with criteria for practical applications, whereas marine sources have only been marginally screened. This work provides an overview on the relevant features of this enzyme and the framework for its application, with a clear emphasis on the use of L-asparaginase from marine sources. The review envisages to highlight the unique properties of marine L-asparaginases that could make them good candidates for medical applications and industries, especially in food safety.
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Affiliation(s)
| | - Ahmad Homaei
- Department of Biology, Faculty of Sciences, University of Hormozgan, Bandar Abbas, Iran.
| | - Pedro Fernandes
- Department of Bioengineering and IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal; Faculty of Engineering, Universidade Lusófona de Humanidades e Tecnologias, Av. Campo Grande 376, 1749-024 Lisboa, Portugal
| | - Sedigheh Javadpour
- Molecular Medicine Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
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18
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Badoei-Dalfard A. L-asparaginase production in the pseudomonas pseudoalcaligenes strain JHS-71 isolated from Jooshan Hot-spring. MOLECULAR BIOLOGY RESEARCH COMMUNICATIONS 2016; 5:1-10. [PMID: 27844015 PMCID: PMC5019328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
L-asparaginase has lots of medical and industrial applications. Ever since L-asparaginase anti-tumor activity was first demonstrated, its production using microbial systems has attracted considerable attention owing to their cost-effective and eco-friendly nature. The aim of this study is to obtain L-asparaginase producing bacteria and determining the enzyme activity. Samples were picked up from Jooshan hot springs located in the Sirch, Kerman. The L-asparaginase producing bacteria were screened on the agar medium supplied with L-asparagine and phenol red indicator dye (pH-7.0). L-asparaginase activity was detected on the basis of pink color around the colony. Enzyme production was also performed based on ammonia detection by Nessler method. Among 24 strains, there were 7 strains which could produce L-asparaginase. Sequencing of 16S rRNA showed that, the best isolates producing L-asparaginase belongs to the Pseudomonas genus. Enzyme activity after 24 and 48 h of incubation showed that Pseudomonas pseudoalcaligenes strain JHS-71 was the best strain that produced L-Asparaginase about 240 (U/ml) after 48h of incubation. Results showed that, L-Asparaginase activity enhanced about 27% in the presence of Co+2. L-asparaginase JHS-71 retained more than 50% of its initial activity in the presence of Cu+2, Mn+2, Zn+2, Mg+2 and Fe+2. Because of various applications of L-asparaginase in biotechnology, P. pseudoalcaligenes strain JHS-71 can be used as a suitable candidate in these fields.
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19
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Lopes AM, Oliveira-Nascimento LD, Ribeiro A, Tairum CA, Breyer CA, Oliveira MAD, Monteiro G, Souza-Motta CMD, Magalhães PDO, Avendaño JGF, Cavaco-Paulo AM, Mazzola PG, Rangel-Yagui CDO, Sette LD, Converti A, Pessoa A. Therapeuticl-asparaginase: upstream, downstream and beyond. Crit Rev Biotechnol 2015; 37:82-99. [DOI: 10.3109/07388551.2015.1120705] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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20
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Batool T, Makky EA, Jalal M, Yusoff MM. A Comprehensive Review on l-Asparaginase and Its Applications. Appl Biochem Biotechnol 2015; 178:900-23. [DOI: 10.1007/s12010-015-1917-3] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 10/29/2015] [Indexed: 11/27/2022]
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21
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Mirouze N, Bidnenko E, Noirot P, Auger S. Genome-wide mapping of TnrA-binding sites provides new insights into the TnrA regulon in Bacillus subtilis. Microbiologyopen 2015; 4:423-35. [PMID: 25755103 PMCID: PMC4475385 DOI: 10.1002/mbo3.249] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 01/22/2015] [Accepted: 02/02/2015] [Indexed: 01/13/2023] Open
Abstract
Under nitrogen limitation conditions, Bacillus subtilis induces a sophisticated network of adaptation responses. More precisely, the B. subtilis TnrA regulator represses or activates directly or indirectly the expression of a hundred genes in response to nitrogen availability. The global TnrA regulon have already been identified among which some directly TnrA-regulated genes have been characterized. However, a genome-wide mapping of in vivo TnrA-binding sites was still needed to clearly define the set of genes directly regulated by TnrA. Using chromatin immunoprecipitation coupled with hybridization to DNA tiling arrays (ChIP-on-chip), we now provide in vivo evidence that TnrA reproducibly binds to 42 regions on the chromosome. Further analysis with real-time in vivo transcriptional profiling, combined with results from previous reports, allowed us to define the TnrA primary regulon. We identified 35 promoter regions fulfilling three criteria necessary to be part of this primary regulon: (i) TnrA binding in ChIP-on-chip experiments and/or in previous in vitro studies; (ii) the presence of a TnrA box; (iii) TnrA-dependent expression regulation. In addition, the TnrA primary regulon delimitation allowed us to improve the TnrA box consensus. Finally, our results reveal new interconnections between the nitrogen regulatory network and other cellular processes.
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Affiliation(s)
- Nicolas Mirouze
- UMR1319 Micalis, INRA, F-78352, Jouy-en-Josas, France.,UMR Micalis, AgroParisTech, F-78352, Jouy-en-Josas, France
| | - Elena Bidnenko
- UMR1319 Micalis, INRA, F-78352, Jouy-en-Josas, France.,UMR Micalis, AgroParisTech, F-78352, Jouy-en-Josas, France
| | - Philippe Noirot
- UMR1319 Micalis, INRA, F-78352, Jouy-en-Josas, France.,UMR Micalis, AgroParisTech, F-78352, Jouy-en-Josas, France
| | - Sandrine Auger
- UMR1319 Micalis, INRA, F-78352, Jouy-en-Josas, France.,UMR Micalis, AgroParisTech, F-78352, Jouy-en-Josas, France
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22
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Sudhir AP, Dave BR, Prajapati AS, Panchal K, Patel D, Subramanian RB. Characterization of a recombinant glutaminase-free L-asparaginase (ansA3) enzyme with high catalytic activity from Bacillus licheniformis. Appl Biochem Biotechnol 2014; 174:2504-15. [PMID: 25224912 DOI: 10.1007/s12010-014-1200-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 08/22/2014] [Indexed: 11/24/2022]
Abstract
L-Asparaginase (3.5.1.1) is an enzyme widely used to treat the acute lymphoblastic leukemia. Two genes coding for L-asparaginase (ansA1 and ansA3) from Bacillus licheniformis MTCC 429 were cloned and overexpressed in Escherichia coli BL21 (DE3) cells. The recombinant proteins were purified to homogeneity by one-step purification process and further characterized for various biochemical parameters. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that both the enzymes are monomers of ∼37 kDa. Recombinant ansA1 was found to be highly unstable, and recombinant ansA3 was catalytically active and stable, which showed an optimum activity of 407.65 IU/mg at 37 °C and pH 8. Recombinant ansA3 showed higher substrate specificity for L-asparagine with negligible glutaminase activity. Kinetic parameters like K m , V max, k cat, and k cat/K m were calculated for recombinant ansA3.
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Affiliation(s)
- Ankit P Sudhir
- BRD School of Biosciences, Sardar Patel Maidan, Sardar Patel University, Vadtal Road, Satellite Campus, PO Box 39, Vallabh Vidyanagar, 388 120, Gujarat, India
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23
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Erenler SO, Geckil H. Effect of Vitreoscilla Hemoglobin and Culture Conditions on Production of Bacterial l-Asparaginase, an Oncolytic Enzyme. Appl Biochem Biotechnol 2014; 173:2140-51. [DOI: 10.1007/s12010-014-1016-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 06/16/2014] [Indexed: 10/25/2022]
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AZARA RIMA, HELIANTI IS, KUSNADI JONI, YUNIANTA YUNIANTA. Cloning and Gene Expression of AnsZ Encoding L-Asparaginase Enzyme from Local Bacillus sp. MICROBIOLOGY INDONESIA 2014. [DOI: 10.5454/mi.8.2.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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El-Nagga NEA, El-Ewasy SM, El-Shweihy NM. Microbial L-asparaginase as a Potential Therapeutic Agent for the Treatment of Acute Lymphoblastic Leukemia: The Pros and Cons. INT J PHARMACOL 2014. [DOI: 10.3923/ijp.2014.182.199] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Studies on optimization of growth parameters for L-asparaginase production by Streptomyces ginsengisoli. ScientificWorldJournal 2014; 2014:895167. [PMID: 24616652 PMCID: PMC3925603 DOI: 10.1155/2014/895167] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Accepted: 12/10/2013] [Indexed: 11/25/2022] Open
Abstract
A species of Streptomyces, Streptomyces ginsengisoli, a river isolate, was evaluated for production of an enzyme, L-asparaginase, with multiple functions mainly anticancer activity. The actinomycete was subjected to submerged fermentation by “shake flask” method. The quantity of L-asparaginase produced was estimated as 3.23 μmol/mL/min. The effect of various culture conditions on L-asparaginase production was studied by adopting a method of variation in one factor at a time. Of the various conditions tested, glucose (followed by starch) and peptone served as good carbon and nitrogen sources, respectively, for maximal production of enzyme at pH 8. The temperature of 30°C and an incubation period of 5 days with 0.05 g% asparagine concentration were found to be optimum for L-asparaginase production.
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Murray DS, Chinnam N, Tonthat NK, Whitfill T, Wray LV, Fisher SH, Schumacher MA. Structures of the Bacillus subtilis glutamine synthetase dodecamer reveal large intersubunit catalytic conformational changes linked to a unique feedback inhibition mechanism. J Biol Chem 2013; 288:35801-11. [PMID: 24158439 DOI: 10.1074/jbc.m113.519496] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glutamine synthetase (GS), which catalyzes the production of glutamine, plays essential roles in nitrogen metabolism. There are two main bacterial GS isoenzymes, GSI-α and GSI-β. GSI-α enzymes, which have not been structurally characterized, are uniquely feedback-inhibited by Gln. To gain insight into GSI-α function, we performed biochemical and cellular studies and obtained structures for all GSI-α catalytic and regulatory states. GSI-α forms a massive 600-kDa dodecameric machine. Unlike other characterized GS, the Bacillus subtilis enzyme undergoes dramatic intersubunit conformational alterations during formation of the transition state. Remarkably, these changes are required for active site construction. Feedback inhibition arises from a hydrogen bond network between Gln, the catalytic glutamate, and the GSI-α-specific residue, Arg(62), from an adjacent subunit. Notably, Arg(62) must be ejected for proper active site reorganization. Consistent with these findings, an R62A mutation abrogates Gln feedback inhibition but does not affect catalysis. Thus, these data reveal a heretofore unseen restructuring of an enzyme active site that is coupled with an isoenzyme-specific regulatory mechanism. This GSI-α-specific regulatory network could be exploited for inhibitor design against Gram-positive pathogens.
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Affiliation(s)
- David S Murray
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239
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Jia M, Xu M, He B, Rao Z. Cloning, expression, and characterization of L-asparaginase from a newly isolated Bacillus subtilis B11-06. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:9428-9434. [PMID: 24003863 DOI: 10.1021/jf402636w] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
This study focused on the cloning, overexpression, and characterization of the gene encoding L-asparaginase (ansZ) from a nonpathogenic strain of Bacillus subtilis B11-06. The recombinant enzyme showed high thermostability and low affinity to L-glutamine. The ansZ gene, encoding a putative L-asparaginase II, was amplified by PCR and expressed in B. subtilis 168 using the shuttle vector pMA5. The activity of the recombinant enzyme was 9.98 U/mL, which was significantly higher than that of B. subtilis B11-06. The recombinant enzyme was purified by a two-step procedure including ammonium sulfate fractionation and hydrophobic interaction chromatography. The optimum pH and temperature of the recombinant enzyme were 7.5 and 40 °C, respectively. The enzyme was quite stable at a pH range of 6.0-9.0 and exhibited about 14.7 and 9.0% retention of activity following 2 h incubation at 50 or 60 °C, respectively. The Km for L-asparagine was 0.43 mM, and the Vmax was 77.51 μM/min. Results of this study also revealed the potential industrial application of this enzyme in reducing acrylamide formation during the potato frying process.
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Affiliation(s)
- Mingmei Jia
- The Key Laboratory of Industrial Biotechnology, Ministry of Educationand Lab of Applied Microbiology and Metabolic Engineering, School of Biotechnology, Jiangnan University , Wuxi, Jiangsu Province 214122, China
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Nayak S, Porob S, Fernandes A, Meena RM, Ramaiah N. PCR detection ofansAfrom marine bacteria and its sequence characteristics fromBacillus tequilensisNIOS4. J Basic Microbiol 2013; 54:162-8. [DOI: 10.1002/jobm.201200355] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Accepted: 09/10/2012] [Indexed: 11/11/2022]
Affiliation(s)
- Sagar Nayak
- Microbial Ecology Laboratory; CSIR-National Institute of Oceanography; Dona Paula Goa India
| | - Seema Porob
- Microbial Ecology Laboratory; CSIR-National Institute of Oceanography; Dona Paula Goa India
| | - Areena Fernandes
- Microbial Ecology Laboratory; CSIR-National Institute of Oceanography; Dona Paula Goa India
| | - Ram Murti Meena
- Microbial Ecology Laboratory; CSIR-National Institute of Oceanography; Dona Paula Goa India
| | - Nagappa Ramaiah
- Microbial Ecology Laboratory; CSIR-National Institute of Oceanography; Dona Paula Goa India
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Huerta-Saquero A, Evangelista-Martínez Z, Moreno-Enriquez A, Perez-Rueda E. Rhizobium etli asparaginase II: an alternative for acute lymphoblastic leukemia (ALL) treatment. Bioengineered 2012; 4:30-6. [PMID: 22895060 PMCID: PMC3566018 DOI: 10.4161/bioe.21710] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Bacterial l-asparaginase has been a universal component of therapies for childhood acute lymphoblastic leukemia since the 1970s. Two principal enzymes derived from Escherichia coli and Erwinia chrysanthemi are the only options clinically approved to date. We recently reported a study of recombinant l-asparaginase (AnsA) from Rhizobium etli and described an increasing type of AnsA family members. Sequence analysis revealed four conserved motifs with notable differences with respect to the conserved regions of amino acid sequences of type I and type II l-asparaginases, particularly in comparison with therapeutic enzymes from E. coli and E. chrysanthemi. These differences suggested a distinct immunological specificity. Here, we report an in silico analysis that revealed immunogenic determinants of AnsA. Also, we used an extensive approach to compare the crystal structures of E. coli and E. chrysantemi asparaginases with a computational model of AnsA and identified immunogenic epitopes. A three-dimensional model of AsnA revealed, as expected based on sequence dissimilarities, completely different folding and different immunogenic epitopes. This approach could be very useful in transcending the problem of immunogenicity in two major ways: by chemical modifications of epitopes to reduce drug immunogenicity, and by site-directed mutagenesis of amino acid residues to diminish immunogenicity without reduction of enzymatic activity.
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Affiliation(s)
- Alejandro Huerta-Saquero
- Departamento de Microbiología Molecular; Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Morelos, México.
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Groot Kormelink T, Koenders E, Hagemeijer Y, Overmars L, Siezen RJ, de Vos WM, Francke C. Comparative genome analysis of central nitrogen metabolism and its control by GlnR in the class Bacilli. BMC Genomics 2012; 13:191. [PMID: 22607086 PMCID: PMC3412718 DOI: 10.1186/1471-2164-13-191] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 03/20/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The assimilation of nitrogen in bacteria is achieved through only a few metabolic conversions between alpha-ketoglutarate, glutamate and glutamine. The enzymes that catalyze these conversions are glutamine synthetase, glutaminase, glutamate dehydrogenase and glutamine alpha-ketoglutarate aminotransferase. In low-GC Gram-positive bacteria the transcriptional control over the levels of the related enzymes is mediated by four regulators: GlnR, TnrA, GltC and CodY. We have analyzed the genomes of all species belonging to the taxonomic families Bacillaceae, Listeriaceae, Staphylococcaceae, Lactobacillaceae, Leuconostocaceae and Streptococcaceae to determine the diversity in central nitrogen metabolism and reconstructed the regulation by GlnR. RESULTS Although we observed a substantial difference in the extent of central nitrogen metabolism in the various species, the basic GlnR regulon was remarkably constant and appeared not affected by the presence or absence of the other three main regulators. We found a conserved regulatory association of GlnR with glutamine synthetase (glnRA operon), and the transport of ammonium (amtB-glnK) and glutamine/glutamate (i.e. via glnQHMP, glnPHQ, gltT, alsT). In addition less-conserved associations were found with, for instance, glutamate dehydrogenase in Streptococcaceae, purine catabolism and the reduction of nitrite in Bacillaceae, and aspartate/asparagine deamination in Lactobacillaceae. CONCLUSIONS Our analyses imply GlnR-mediated regulation in constraining the import of ammonia/amino-containing compounds and the production of intracellular ammonia under conditions of high nitrogen availability. Such a role fits with the intrinsic need for tight control of ammonia levels to limit futile cycling.
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Affiliation(s)
- Tom Groot Kormelink
- Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands
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Flórez LA, Gunka K, Polanía R, Tholen S, Stülke J. SPABBATS: A pathway-discovery method based on Boolean satisfiability that facilitates the characterization of suppressor mutants. BMC SYSTEMS BIOLOGY 2011; 5:5. [PMID: 21219666 PMCID: PMC3024933 DOI: 10.1186/1752-0509-5-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Accepted: 01/11/2011] [Indexed: 01/25/2023]
Abstract
Background Several computational methods exist to suggest rational genetic interventions that improve the productivity of industrial strains. Nonetheless, these methods are less effective to predict possible genetic responses of the strain after the intervention. This problem requires a better understanding of potential alternative metabolic and regulatory pathways able to counteract the targeted intervention. Results Here we present SPABBATS, an algorithm based on Boolean satisfiability (SAT) that computes alternative metabolic pathways between input and output species in a reconstructed network. The pathways can be constructed iteratively in order of increasing complexity. SPABBATS allows the accumulation of intermediates in the pathways, which permits discovering pathways missed by most traditional pathway analysis methods. In addition, we provide a proof of concept experiment for the validity of the algorithm. We deleted the genes for the glutamate dehydrogenases of the Gram-positive bacterium Bacillus subtilis and isolated suppressor mutant strains able to grow on glutamate as single carbon source. Our SAT approach proposed candidate alternative pathways which were decisive to pinpoint the exact mutation of the suppressor strain. Conclusions SPABBATS is the first application of SAT techniques to metabolic problems. It is particularly useful for the characterization of metabolic suppressor mutants and can be used in a synthetic biology setting to design new pathways with specific input-output requirements.
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Affiliation(s)
- Lope A Flórez
- Department of General Microbiology, Georg-August-University of Göttingen, Germany
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Onishi Y, Yano S, Thongsanit J, Takagi K, Yoshimune K, Wakayama M. Expression in Escherichia coli of a gene encoding type II l-asparaginase from Bacillus subtilis, and characterization of its unique properties. ANN MICROBIOL 2010. [DOI: 10.1007/s13213-010-0167-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Kumar S, Veeranki VD, Pakshirajan K. Assessment of Physical Process Conditions for Enhanced Production of Novel Glutaminase-Free L-Asparaginase from Pectobacterium carotovorum MTCC 1428. Appl Biochem Biotechnol 2010; 163:327-37. [DOI: 10.1007/s12010-010-9041-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Accepted: 07/12/2010] [Indexed: 11/24/2022]
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Bandgar BP, Gawande SS, Warangkar SC, Totre JV. Silica-supported fluoroboric acid (HBF4–SiO2) catalyzed highly productive synthesis of thiomorpholides as activators of l-asparaginase as well as the antioxidant agent. Bioorg Med Chem 2010; 18:3618-24. [DOI: 10.1016/j.bmc.2010.03.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Revised: 03/12/2010] [Accepted: 03/13/2010] [Indexed: 11/25/2022]
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Warangkar SC, Khobragade CN. Purification, Characterization, and Effect of Thiol Compounds on Activity of the Erwinia carotovora L-Asparaginase. Enzyme Res 2009; 2010:165878. [PMID: 21048860 PMCID: PMC2956972 DOI: 10.4061/2010/165878] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Accepted: 07/31/2009] [Indexed: 11/20/2022] Open
Abstract
L-asparaginase was extracted from Erwinia carotovora and purified by ammonium sulfate fractionation (60–70%), Sephadex G-100, CM cellulose, and DEAE sephadex chromatography. The apparent Mr of enzyme under nondenaturing and denaturing conditions was 150 kDa and 37 ± 0.5 kDa, respectively. L-asparaginase activity was studied in presence of thiols, namely, L-cystine (Cys), L-methionine (Met), N-acetyl cysteine (NAC), and reduced glutathione (GSH). Kinetic parameters in presence of thiols (10–400 μM) showed an increase in Vmax values (2000, 2223, 2380, 2500, and control 1666.7 μmoles mg−1min−1) and a decrease in Km values (0.086, 0.076, 0.062, 0.055 and control 0.098 mM) indicating nonessential mode of activation. KA values displayed propensity to bind thiols. A decrease in Vmax/Km ratio in concentration plots showed inverse relationship between free thiol groups (NAC and GSH) and bound thiol group (Cys and Met). Enzyme activity was enhanced in presence of thiol protecting reagents like dithiothreitol (DTT), 2-mercaptoethanol (2-ME), and GSH, but inhibited by p-chloromercurybenzoate (PCMB) and iodoacetamide (IA).
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Affiliation(s)
- Suchita C Warangkar
- Biotechnology Research Laboratory, School of Life Sciences, Swami Ramanand Teerth Marathwada University, Nanded 431606, India
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Kumar S, Pakshirajan K, Venkata Dasu V. Development of medium for enhanced production of glutaminase-free l-asparaginase from Pectobacterium carotovorum MTCC 1428. Appl Microbiol Biotechnol 2009; 84:477-86. [DOI: 10.1007/s00253-009-1973-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 03/18/2009] [Accepted: 03/19/2009] [Indexed: 11/25/2022]
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Novel trans-Acting Bacillus subtilis glnA mutations that derepress glnRA expression. J Bacteriol 2009; 191:2485-92. [PMID: 19233925 DOI: 10.1128/jb.01734-08] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus subtilis contains two nitrogen transcription factors, GlnR and TnrA. The activities of GlnR and TnrA are regulated by direct protein-protein interactions with the feedback-inhibited form of glutamine synthetase (GS). To look for other factors involved in regulating GlnR activity, we isolated mutants with constitutive glnRA expression (Gln(C)). The twenty-seven Gln(C) mutants isolated in this mutant screen all contained mutations tightly linked to the glnRA operon which encodes GlnR (glnR) and GS (glnA). Four Gln(C) mutants contained mutations in the glnR gene that most likely impair the ability of GlnR to bind DNA. Three other Gln(C) mutants contained novel glnA mutations (S55F, V173I, and L174F). GlnR regulation was completely relieved in the three glnA mutants, while only modest defects in TnrA regulation were observed. In vitro enzymatic assays showed that the purified S55F mutant enzyme was catalytically defective while the V173I and L174F enzymes were highly resistant to feedback inhibition. The V173I and L174F GS proteins were found to require higher glutamine concentrations than the wild-type GS to regulate the DNA-binding activities of GlnR and TnrA in vitro. These results are consistent with a model where feedback-inhibited GS is the only cellular factor involved in regulating the activity of GlnR in B. subtilis.
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Yano S, Minato R, Thongsanit J, Tachiki T, Wakayama M. Overexpression of type I L-asparaginase ofBacillus subtilis inEscherichia coli, rapid purification and characterisation of recombinant type I L-asparaginase. ANN MICROBIOL 2008. [DOI: 10.1007/bf03175579] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Abstract
Lactic acid bacteria (LAB) constitute a diverse group of Gram positive obligately fermentative microorganisms which include both beneficial and pathogenic strains. LAB generally have complex nutritional requirements and therefore they are usually associated with nutrient-rich environments such as animal bodies, plants and foodstuffs. Amino acids represent an important resource for LAB and their utilization serves a number of physiological roles such as intracellular pH control, generation of metabolic energy or redox power, and resistance to stress. As a consequence, the regulation of amino acid catabolism involves a wide set of both general and specific regulators and shows significant differences among LAB. Moreover, due to their fermentative metabolism, LAB amino acid catabolic pathways in some cases differ significantly from those described in best studied prokaryotic model organisms such as Escherichia coli or Bacillus subtilis. Thus, LAB amino acid catabolism constitutes an interesting case for the study of metabolic pathways. Furthermore, LAB are involved in the production of a great variety of fermented products so that the products of amino acid catabolism are also relevant for the safety and the quality of fermented products.
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Affiliation(s)
- María Fernández
- Instituto de Productos Lácteos de Asturias CSIC, Crta de Infiesto s/n, Villaviciosa, Asturias, Spain
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Goelzer A, Bekkal Brikci F, Martin-Verstraete I, Noirot P, Bessières P, Aymerich S, Fromion V. Reconstruction and analysis of the genetic and metabolic regulatory networks of the central metabolism of Bacillus subtilis. BMC SYSTEMS BIOLOGY 2008; 2:20. [PMID: 18302748 PMCID: PMC2311275 DOI: 10.1186/1752-0509-2-20] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Accepted: 02/26/2008] [Indexed: 12/15/2022]
Abstract
Background Few genome-scale models of organisms focus on the regulatory networks and none of them integrates all known levels of regulation. In particular, the regulations involving metabolite pools are often neglected. However, metabolite pools link the metabolic to the genetic network through genetic regulations, including those involving effectors of transcription factors or riboswitches. Consequently, they play pivotal roles in the global organization of the genetic and metabolic regulatory networks. Results We report the manually curated reconstruction of the genetic and metabolic regulatory networks of the central metabolism of Bacillus subtilis (transcriptional, translational and post-translational regulations and modulation of enzymatic activities). We provide a systematic graphic representation of regulations of each metabolic pathway based on the central role of metabolites in regulation. We show that the complex regulatory network of B. subtilis can be decomposed as sets of locally regulated modules, which are coordinated by global regulators. Conclusion This work reveals the strong involvement of metabolite pools in the general regulation of the metabolic network. Breaking the metabolic network down into modules based on the control of metabolite pools reveals the functional organization of the genetic and metabolic regulatory networks of B. subtilis.
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Affiliation(s)
- Anne Goelzer
- Unité Mathématique, Informatique et Génomes, Institut National Recherche Agronomique, UR1077, F-78350 Jouy-en-Josas, France.
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Bacillus subtilis glutamine synthetase regulates its own synthesis by acting as a chaperone to stabilize GlnR-DNA complexes. Proc Natl Acad Sci U S A 2008; 105:1014-9. [PMID: 18195355 DOI: 10.1073/pnas.0709949105] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Bacillus subtilis GlnR repressor controls gene expression in response to nitrogen availability. Because all GlnR-regulated genes are expressed constitutively in mutants lacking glutamine synthetase (GS), GS is required for repression by GlnR. Feedback-inhibited GS (FBI-GS) was shown to activate GlnR DNA binding with an in vitro electophoretic mobility shift assay (EMSA). The activation of GlnR DNA binding by GS in these experiments depended on the feedback inhibitor glutamine and did not occur with mutant GS proteins defective in regulating GlnR activity in vivo. Although stable GS-GlnR-DNA ternary complexes were not observed in the EMSA experiments, cross-linking experiments showed that a protein-protein interaction occurs between GlnR and FBI-GS. This interaction was reduced in the absence of the feedback inhibitor glutamine and with mutant GS proteins. Because FBI-GS significantly reduced the dissociation rate of the GlnR-DNA complexes, the stability of these complexes is enhanced by FBI-GS. These results argue that FBI-GS acts as a chaperone that activates GlnR DNA binding through a transient protein-protein interaction that stabilizes GlnR-DNA complexes. GS was shown to control the activity of the B. subtilis nitrogen transcription factor TnrA by forming a stable complex between FBI-GS and TnrA that inhibits TnrA DNA binding. Thus, B. subtilis GS is an enzyme with dual catalytic and regulatory functions that uses distinct mechanisms to control the activity of two different transcription factors.
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Prakasham RS, Rao CS, Rao RS, Lakshmi GS, Sarma PN. l-asparaginase production by isolated Staphylococcus sp. ? 6A: design of experiment considering interaction effect for process parameter optimization. J Appl Microbiol 2007; 102:1382-91. [PMID: 17448173 DOI: 10.1111/j.1365-2672.2006.03173.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS Evaluation of fermentation process parameter interactions for the production of l-asparaginase by isolated Staphylococcus sp. - 6A. METHODS AND RESULTS Fractional factorial design of experimentation (L18 orthogonal array of Taguchi methodology) was adopted to optimize nutritional (carbon and nitrogen sources), physiological (incubation temperature, medium pH, aeration and agitation) and microbial (inoculum level) fermentation factors. The experimental results and software predicted enzyme production values were comparable. CONCLUSION Incubation temperature, inoculum level and medium pH, among all fermentation factors, were major influential parameters at their individual level, and contributed to more than 60% of total l-asparaginase production. Interaction data of selected fermentation parameters could be classified as least and most significant at individual and interactive levels. Aeration and agitation were most significant at interactive level, but least significant at individual level, and showed maximum severity index and vice versa at enzyme production. SIGNIFICANCE AND IMPACT OF THE STUDY All selected factors showed impact on l-asparaginase enzyme production by this isolated microbial strain either at the individual or interactive level. Incubation temperature, inoculum concentration, pH of the medium and nutritional source (glucose and ammonium chloride) had impact at individual level, while aeration, agitation and incubation time showed influence at interactive level. Significant improvement (ninefold increase) in enzyme production by this microbial isolate was noted under optimized environment.
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Affiliation(s)
- R S Prakasham
- Bioengineering and Environmental Centre, Indian Institute of Chemical Technology, Hyderabad, India.
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Thomaides HB, Davison EJ, Burston L, Johnson H, Brown DR, Hunt AC, Errington J, Czaplewski L. Essential bacterial functions encoded by gene pairs. J Bacteriol 2006; 189:591-602. [PMID: 17114254 PMCID: PMC1797375 DOI: 10.1128/jb.01381-06] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To address the need for new antibacterials, a number of bacterial genomes have been systematically disrupted to identify essential genes. Such programs have focused on the disruption of single genes and may have missed functions encoded by gene pairs or multiple genes. In this work, we hypothesized that we could predict the identity of pairs of proteins within one organism that have the same function. We identified 135 putative protein pairs in Bacillus subtilis and attempted to disrupt the genes forming these, singly and then in pairs. The single gene disruptions revealed new genes that could not be disrupted individually and other genes required for growth in minimal medium or for sporulation. The pairwise disruptions revealed seven pairs of proteins that are likely to have the same function, as the presence of one protein can compensate for the absence of the other. Six of these pairs are essential for bacterial viability and in four cases show a pattern of species conservation appropriate for potential antibacterial development. This work highlights the importance of combinatorial studies in understanding gene duplication and identifying functional redundancy.
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Affiliation(s)
- Helena B Thomaides
- Prolysis Ltd., Begbroke Science Park, Sandy Lane, Yarnton OX5 1PF, Oxfordshire, UK.
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Wray LV, Fisher SH. Functional analysis of the carboxy-terminal region of Bacillus subtilis TnrA, a MerR family protein. J Bacteriol 2006; 189:20-7. [PMID: 17085574 PMCID: PMC1797213 DOI: 10.1128/jb.01238-06] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Bacillus subtilis TnrA transcription factor belongs to the MerR family of proteins and regulates gene expression during nitrogen-limited growth. When B. subtilis cells are grown with excess nitrogen, feedback-inhibited glutamine synthetase forms a protein-protein complex with TnrA that prevents TnrA from binding to DNA. The C-terminal region of TnrA is required for the interaction with glutamine synthetase. Alanine scanning mutagenesis of the C-terminal region of TnrA identified three classes of mutants that altered the regulation by glutamine synthetase. While expression of the TnrA-regulated amtB gene was expressed constitutively in the class I (M96A, Q100A, and A103G) and class II (L97A, L101A, and F105A) mutants, the class II mutants were unable to grow on minimal medium unless a complex mixture of amino acids was present. The class III tnrA mutants (R93A, G99A, N102A, H104A, and Y107A mutants) were partially defective in the regulation of TnrA activity. In vitro experiments showed that feedback-inhibited glutamine synthetase had a significantly reduced ability to inhibit the DNA-binding activity of several class I and class II mutant TnrA proteins. A coiled-coil homology model of the C-terminal region of TnrA is used to explain the properties of the class I and II mutant proteins. The C-terminal region of TnrA corresponds to a dimerization domain in other MerR family proteins. Surprisingly, gel filtration and cross-linking analysis showed that a truncated TnrA protein which contained only the N-terminal DNA binding domain was dimeric. The implications of these results for the structure of TnrA are discussed.
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Affiliation(s)
- Lewis V Wray
- Department of Microbiology, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118-2526, USA
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Geckil H, Gencer S, Ates B, Ozer U, Uckun M, Yilmaz I. Effect of Vitreoscilla hemoglobin on production of a chemotherapeutic enzyme, L-asparaginase, by Pseudomonas aeruginosa. Biotechnol J 2006; 1:203-8. [PMID: 16892249 DOI: 10.1002/biot.200500048] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The production of L-asparaginase, an enzyme widely used in cancer chemotherapy, is mainly regulated by carbon catabolite repression and oxygen. This study was carried out to understand how different carbon sources and Vitreoscilla hemoglobin (VHb) affect the production of this enzyme in Pseudomonas aeruginosa and its VHb-expressing recombinant strain (PaJC). Both strains grown with various carbon sources showed a distinct profile of the enzyme activity. Compared to no carbohydrate supplemented medium, glucose caused a slight repression of L-asparaginase in P. aeruginosa, while it stimulated it in the PaJC strain. Glucose, regarded as one of the inhibitory sugars for the production L-asparaginase by other bacteria, was determined to be the favorite carbon source compared to lactose, glycerol and mannitol. Furthermore, contrary to common knowledge of oxygen repression of L-asparaginase in other bacteria, oxygen uptake provided by VHb was determined to even stimulate the L-asparaginase synthesis by P. aeruginosa. This study, for the first time, shows that in P. aeruginosa utilizing a recombinant oxygen uptake system, VHb, L-asparaginase synthesis is stimulated by glucose and other carbohydrate sources compared to the host strain. It is concluded that carbon catabolite and oxygen repression of L-asparaginase in fermentative bacteria is not the case for a respiratory non-fermentative bacterium like P. aeruginosa.
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Affiliation(s)
- Hikmet Geckil
- Department of Biology, Inonu University, Malatya 44280, Turkey.
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Fisher SH, Wray LV. Feedback-resistant mutations in Bacillus subtilis glutamine synthetase are clustered in the active site. J Bacteriol 2006; 188:5966-74. [PMID: 16885465 PMCID: PMC1540052 DOI: 10.1128/jb.00544-06] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The feedback-inhibited form of Bacillus subtilis glutamine synthetase regulates the activity of the TnrA transcription factor through a protein-protein interaction that prevents TnrA from binding to DNA. Five mutants containing feedback-resistant glutamine synthetases (E65G, S66P, M68I, H195Y, and P318S) were isolated by screening for colonies capable of cross-feeding Gln(-) cells. In vitro enzymatic assays revealed that the mutant enzymes had increased resistance to inhibition by glutamine, AMP, and methionine sulfoximine. The mutant proteins had a variety of enzymatic alterations that included changes in the levels of enzymatic activity and in substrate K(m) values. Constitutive expression of TnrA- and GlnR-regulated genes was seen in all five mutants. In gel mobility shift assays, the E65G and S66P enzymes were unable to inhibit TnrA DNA binding, while the other three mutant proteins (M68I, H195Y, and P318S) showed partial inhibition of TnrA DNA binding. A homology model of B. subtilis glutamine synthetase revealed that the five mutated amino acid residues are located in the enzyme active site. These observations are consistent with the hypothesis that glutamine and AMP bind at the active site to bring about feedback inhibition of glutamine synthetase.
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Affiliation(s)
- Susan H Fisher
- Department of Microbiology, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118, USA.
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Zalieckas JM, Wray LV, Fisher SH. Cross-regulation of the Bacillus subtilis glnRA and tnrA genes provides evidence for DNA binding site discrimination by GlnR and TnrA. J Bacteriol 2006; 188:2578-85. [PMID: 16547045 PMCID: PMC1428417 DOI: 10.1128/jb.188.7.2578-2585.2006] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Two Bacillus subtilis transcriptional factors, TnrA and GlnR, regulate gene expression in response to changes in nitrogen availability. These two proteins have similar amino acid sequences in their DNA binding domains and bind to DNA sites (GlnR/TnrA sites) that have the same consensus sequence. Expression of the tnrA gene was found to be activated by TnrA and repressed by GlnR. Mutational analysis demonstrated that a GlnR/TnrA site which lies immediately upstream of the -35 region of the tnrA promoter is required for regulation of tnrA expression by both GlnR and TnrA. Expression of the glnRA operon, which contains two GlnR/TnrA binding sites (glnRAo1 and glnRAo2) in its promoter region, is repressed by both GlnR and TnrA. The glnRAo2 site, which overlaps the -35 region of the glnRA promoter, was shown to be required for regulation by both GlnR and TnrA, while the glnRAo1 site which lies upstream of the -35 promoter region is only involved in GlnR-mediated regulation. Examination of TnrA binding to tnrA and glnRA promoter DNA in gel mobility shift experiments showed that TnrA bound with an equilibrium dissociation binding constant of 55 nM to the GlnR/TnrA site in the tnrA promoter region, while the affinities of TnrA for the two GlnR/TnrA sites in the glnRA promoter region were greater than 3 muM. These results demonstrate that GlnR and TnrA cross-regulate each other's expression and that there are differences in their DNA-binding specificities.
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Affiliation(s)
- Jill M Zalieckas
- Department of Microbiology, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118, USA
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Tojo S, Satomura T, Morisaki K, Yoshida KI, Hirooka K, Fujita Y. Negative transcriptional regulation of the ilv-leu operon for biosynthesis of branched-chain amino acids through the Bacillus subtilis global regulator TnrA. J Bacteriol 2004; 186:7971-9. [PMID: 15547269 PMCID: PMC529080 DOI: 10.1128/jb.186.23.7971-7979.2004] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The Bacillus subtilis ilv-leu operon is involved in the synthesis of branched-chain amino acids (valine, isoleucine, and leucine). The two- to threefold repression of expression of the ilv-leu operon during logarithmic-phase growth under nitrogen-limited conditions, which was originally detected by a DNA microarray analysis to compare the transcriptomes from the wild-type and tnrA mutant strains, was confirmed by lacZ fusion and Northern experiments. A genome-wide TnrA box search revealed a candidate box approximately 200 bp upstream of the transcription initiation base of the ilv-leu operon, the TnrA binding to which was verified by gel retardation and DNase I footprinting analyses. Deletion and base substitution of the TnrA box sequence affected the ilv-leu promoter activity in vivo, implying that TnrA bound to the box might be able to inhibit the promoter activity, possibly through DNA bending. The negative control of the expression of the ilv-leu operon by TnrA, which is considered to represent rather fine-tuning (two- to threefold), is a novel regulatory link between nitrogen and amino acid metabolism.
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Affiliation(s)
- Shigeo Tojo
- Department of Biotechnology, Faculty of Life Science and Technology, Fukuyama University, Fukuyama, Japan
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