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Split NanoLuc technology allows quantitation of interactions between PII protein and its receptors with unprecedented sensitivity and reveals transient interactions. Sci Rep 2021; 11:12535. [PMID: 34131190 PMCID: PMC8206089 DOI: 10.1038/s41598-021-91856-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 05/24/2021] [Indexed: 11/08/2022] Open
Abstract
PII proteins constitute a widespread signal transduction superfamily in the prokaryotic world. The canonical PII signal proteins sense metabolic state of the cells by binding the metabolite molecules ATP, ADP and 2-oxoglutarate. Depending on bound effector molecule, PII proteins interact with and modulate the activity of multiple target proteins. To investigate the complexity of interactions of PII with target proteins, analytical methods that do not disrupt the native cellular context are required. To this purpose, split luciferase proteins have been used to develop a novel complementation reporter called NanoLuc Binary Technology (NanoBiT). The luciferase NanoLuc is divided in two subunits: a 18 kDa polypeptide termed "Large BiT" and a 1.3 kDa peptide termed "Small BiT", which only weakly associate. When fused to proteins of interest, they reconstitute an active luciferase when the proteins of interest interact. Therefore, we set out to develop a new NanoBiT sensor based on the interaction of PII protein from Synechocystis sp. PCC6803 with PII-interacting protein X (PipX) and N-acetyl-L-glutamate kinase (NAGK). The novel NanoBiT sensor showed unprecedented sensitivity, which made it possible to detect even weak and transient interactions between PII variants and their interacting partners, thereby shedding new light in PII signalling processes.
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Bolay P, Rozbeh R, Muro-Pastor MI, Timm S, Hagemann M, Florencio FJ, Forchhammer K, Klähn S. The Novel P II-Interacting Protein PirA Controls Flux into the Cyanobacterial Ornithine-Ammonia Cycle. mBio 2021; 12:e00229-21. [PMID: 33758091 PMCID: PMC8092223 DOI: 10.1128/mbio.00229-21] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 02/16/2021] [Indexed: 12/11/2022] Open
Abstract
Among prokaryotes, cyanobacteria have an exclusive position as they perform oxygenic photosynthesis. Cyanobacteria substantially differ from other bacteria in further aspects, e.g., they evolved a plethora of unique regulatory mechanisms to control primary metabolism. This is exemplified by the regulation of glutamine synthetase (GS) via small proteins termed inactivating factors (IFs). Here, we reveal another small protein, encoded by the ssr0692 gene in the model strain Synechocystis sp. PCC 6803, that regulates flux into the ornithine-ammonia cycle (OAC), the key hub of cyanobacterial nitrogen stockpiling and remobilization. This regulation is achieved by the interaction with the central carbon/nitrogen control protein PII, which commonly controls entry into the OAC by activating the key enzyme of arginine synthesis, N-acetyl-l-glutamate kinase (NAGK). In particular, the Ssr0692 protein competes with NAGK for PII binding and thereby prevents NAGK activation, which in turn lowers arginine synthesis. Accordingly, we termed it PII-interacting regulator of arginine synthesis (PirA). Similar to the GS IFs, PirA accumulates in response to ammonium upshift due to relief from repression by the global nitrogen control transcription factor NtcA. Consistent with this, the deletion of pirA affects the balance of metabolite pools of the OAC in response to ammonium shocks. Moreover, the PirA-PII interaction requires ADP and is prevented by PII mutations affecting the T-loop conformation, the major protein interaction surface of this signal processing protein. Thus, we propose that PirA is an integrator determining flux into N storage compounds not only depending on the N availability but also the energy state of the cell.IMPORTANCE Cyanobacteria contribute a significant portion to the annual oxygen yield and play important roles in biogeochemical cycles, e.g., as major primary producers. Due to their photosynthetic lifestyle, cyanobacteria also arouse interest as hosts for the sustainable production of fuel components and high-value chemicals. However, their broad application as microbial cell factories is hampered by limited knowledge about the regulation of metabolic fluxes in these organisms. Our research identified a novel regulatory protein that controls nitrogen flux, in particular arginine synthesis. Besides its role as a proteinogenic amino acid, arginine is a precursor for the cyanobacterial storage compound cyanophycin, which is of potential interest to biotechnology. Therefore, the obtained results will not only enhance our understanding of flux control in these organisms but also help to provide a scientific basis for targeted metabolic engineering and, hence, the design of photosynthesis-driven biotechnological applications.
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Affiliation(s)
- Paul Bolay
- Helmholtz Centre for Environmental Research, Department of Solar Materials, Leipzig, Germany
| | - Rokhsareh Rozbeh
- Interfaculty Institute for Microbiology and Infection Medicine, Organismic Interactions Department, Tübingen University, Tübingen, Germany
| | - M Isabel Muro-Pastor
- Instituto de Bioquímica Vegetal y Fotosíntesis, CSIC-Universidad de Sevilla, Sevilla, Spain
| | - Stefan Timm
- Department of Plant Physiology, University of Rostock, Rostock, Germany
| | - Martin Hagemann
- Department of Plant Physiology, University of Rostock, Rostock, Germany
| | - Francisco J Florencio
- Instituto de Bioquímica Vegetal y Fotosíntesis, CSIC-Universidad de Sevilla, Sevilla, Spain
| | - Karl Forchhammer
- Interfaculty Institute for Microbiology and Infection Medicine, Organismic Interactions Department, Tübingen University, Tübingen, Germany
| | - Stephan Klähn
- Helmholtz Centre for Environmental Research, Department of Solar Materials, Leipzig, Germany
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Elmetwally MA, Halawa AA, Tang W, Wu G, Bazer FW. Effects of Bisphenol A on expression of genes related to amino acid transporters, insulin- like growth factor, aquaporin and amino acid release by porcine trophectoderm cells. Reprod Toxicol 2020; 96:241-248. [PMID: 32710935 DOI: 10.1016/j.reprotox.2020.07.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/16/2020] [Accepted: 07/19/2020] [Indexed: 11/16/2022]
Abstract
The peri-implantation period of pregnancy is critical for conceptus development, implantation, and signaling for establishment of pregnancy. This study evaluated the effects of bisphenol A (BPA) on proliferation, adhesion, and migration of porcine trophectoderm (pTr2) cells, expression of transporters of arginine and synthesis of amino acids. All concentrations of BPA decreased proliferation and adhesion of pTr2 cells after 96 h compared to the control group. Lower concentrations of BPA (1 × 10-9, 1 × 10-8, 10-7M) increased (P < 0.05), but higher concentrations of BPA (1 × 10-5, 1 × 10-4 M) decreased migration of pTr2 cells. BPA increased expression of SLC7A1 mRNA at lower concentrations (1 × 10-9 to 1 × 10-6M) and SL7A6, another cationic acid transporter, at higher concentrations (1 × 10-5, 1 × 10-4 M). BPA also down-regulated the expression of IGF1 and IGF1 receptor at concentrations of 1 × 10-7 to 1 × 10-4 M compared to the control group. The expression of mRNAs for aquaporins (AQP) 3 and 4 were reduced at all concentrations of BPA, but at lower concentrations of BPA, (1 × 10-9 to 1 × 10-8M) expression of AQP9 mRNA increased and the expression of AQP11 was not affected by BPA (P > 0.05). There was an inhibitory effect of BPA on the release of synthesis of asparagine, threonine, taurine, tryptophan, and ornithine into the culture medium by pTr2 cells. Collectively, BPA adversely affected the expression of transporters for cationic amino acids like arginine, as well as AQPs, IGF1, and IGF1R associated with proliferation, migration, and adhesion of pTr2 cells. Those adverse effects would likely increase pregnancy losses during the peri-implantation period of pregnancy.
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Affiliation(s)
- Mohammed A Elmetwally
- Department of Animal Science, United States; Center for Animal Biotechnology and Genomics, Texas A&M University, College Station, TX 77843, United States; Department of Theriogenology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt
| | - Amal A Halawa
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt
| | - Wanjin Tang
- Department of Animal Science, United States; Center for Animal Biotechnology and Genomics, Texas A&M University, College Station, TX 77843, United States
| | - Guoyao Wu
- Department of Animal Science, United States; Center for Animal Biotechnology and Genomics, Texas A&M University, College Station, TX 77843, United States
| | - Fuller W Bazer
- Department of Animal Science, United States; Center for Animal Biotechnology and Genomics, Texas A&M University, College Station, TX 77843, United States.
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PII Signal Transduction Protein GlnK Alleviates Feedback Inhibition of N-Acetyl-l-Glutamate Kinase by l-Arginine in Corynebacterium glutamicum. Appl Environ Microbiol 2020; 86:AEM.00039-20. [PMID: 32060028 DOI: 10.1128/aem.00039-20] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 02/04/2020] [Indexed: 12/13/2022] Open
Abstract
PII signal transduction proteins are ubiquitous and highly conserved in bacteria, archaea, and plants and play key roles in controlling nitrogen metabolism. However, research on biological functions and regulatory targets of PII proteins remains limited. Here, we illustrated experimentally that the PII protein Corynebacterium glutamicum GlnK (CgGlnK) increased l-arginine yield when glnK was overexpressed in Corynebacterium glutamicum Data showed that CgGlnK regulated l-arginine biosynthesis by upregulating the expression of genes of the l-arginine metabolic pathway and interacting with N-acetyl-l-glutamate kinase (CgNAGK), the rate-limiting enzyme in l-arginine biosynthesis. Further assays indicated that CgGlnK contributed to alleviation of the feedback inhibition of CgNAGK caused by l-arginine. In silico analysis of the binding interface of CgGlnK-CgNAGK suggested that the B and T loops of CgGlnK mainly interacted with C and N domains of CgNAGK. Moreover, F11, R47, and K85 of CgGlnK were identified as crucial binding sites that interact with CgNAGK via hydrophobic interaction and H bonds, and these interactions probably had a positive effect on maintaining the stability of the complex. Collectively, this study reveals PII-NAGK interaction in nonphotosynthetic microorganisms and further provides insights into the regulatory mechanism of PII on amino acid biosynthesis in corynebacteria.IMPORTANCE Corynebacteria are safe industrial producers of diverse amino acids, including l-glutamic acid and l-arginine. In this study, we showed that PII protein GlnK played an important role in l-glutamic acid and l-arginine biosynthesis in C. glutamicum Through clarifying the molecular mechanism of CgGlnK in l-arginine biosynthesis, the novel interaction between CgGlnK and CgNAGK was revealed. The alleviation of l-arginine inhibition of CgNAGK reached approximately 48.21% by CgGlnK addition, and the semi-inhibition constant of CgNAGK increased 1.4-fold. Furthermore, overexpression of glnK in a high-yield l-arginine-producing strain and fermentation of the recombinant strain in a 5-liter bioreactor led to a remarkably increased production of l-arginine, 49.978 g/liter, which was about 22.61% higher than that of the initial strain. In conclusion, this study provides a new strategy for modifying amino acid biosynthesis in C. glutamicum.
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The PII signaling protein from red algae represents an evolutionary link between cyanobacterial and Chloroplastida PII proteins. Sci Rep 2018; 8:790. [PMID: 29335634 PMCID: PMC5768801 DOI: 10.1038/s41598-017-19046-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 12/15/2017] [Indexed: 11/16/2022] Open
Abstract
PII superfamily consists of widespread signal transduction proteins found in all domains of life. Whereas they are well-studied in Archaea, Bacteria and Chloroplastida, no PII homolog has been analyzed in Rhodophyta (red algae), where PII is encoded by a chloroplast localized glnB gene. Here, we characterized relevant sensory properties of PII from the red alga Porphyra purpurea (PpPII) in comparison to PII proteins from different phyla of oxygenic phototrophs (cyanobacteria, Chlamydomonas and Physcomitrella) to assess evolutionary conservation versus adaptive properties. Like its cyanobacterial counterparts, PpPII binds ATP/ADP and 2-oxoglutarate in synergy with ATP. However, green algae and land plant PII proteins lost the ability to bind ADP. In contrast to PII proteins from green algae and land plants, PpPII enhances the activity of N-acetyl-L-glutamate kinase (NAGK) and relieves it from feedback inhibition by arginine in a glutamine-independent manner. Like PII from Chloroplastida, PpPII is not able to interact with the cyanobacterial transcriptional co-activator PipX. These data emphasize the conserved role of NAGK as a major PII-interactor throughout the evolution of oxygenic phototrophs, and confirms the specific role of PipX for cyanobacteria. Our results highlight the PII signaling system in red algae as an evolutionary intermediate between Cyanobacteria and Chlorophyta.
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Jiang K, Xue Y, Ma Y. Identification of N(α)-acetyl-α-lysine as a probable thermolyte and its accumulation mechanism in Salinicoccus halodurans H3B36. Sci Rep 2015; 5:18518. [PMID: 26687465 PMCID: PMC4685198 DOI: 10.1038/srep18518] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 10/30/2015] [Indexed: 11/09/2022] Open
Abstract
Salinicoccus halodurans H3B36 is a moderate halophile that was isolated from a 3.2-m-deep sediment sample in Qaidam Basin, China. Our results suggest that N(α)-acetyl-α-lysine can accumulate and act as a probable thermolyte in this strain. The accumulation mechanism and biosynthetic pathway for this rare compatible solute were also elucidated. We confirmed that the de novo synthesis pathway of N(α)-acetyl-α-lysine in this strain starts from aspartate and passes through lysine. Through RNA sequencing, we also found an 8-gene cluster (orf_1582-1589) and another gene (orf_2472) that might encode the biosynthesis of N(α)-acetyl-α-lysine in S. halodurans H3B36. Orf_192, orf_193, and orf_1259 might participate in the transportation of precursors for generating N(α)-acetyl-α-lysine under the heat stress. The transcriptome reported here also generated a global view of heat-induced changes and yielded clues for studying the regulation of N(α)-acetyl-α-lysine accumulation. Heat stress triggered a global transcriptional disturbance and generated a series of actions to adapt the strain to heat stress. Furthermore, the transcriptomic results showed that the regulon of RpoN (orf_2534) may be critical to conferring heat stress tolerance and survival to S. halodurans.
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Affiliation(s)
- Kai Jiang
- State Key Laboratory of Microbial Resources and National Engineering Laboratory for Industrial Enzymes, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yanfen Xue
- State Key Laboratory of Microbial Resources and National Engineering Laboratory for Industrial Enzymes, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yanhe Ma
- State Key Laboratory of Microbial Resources and National Engineering Laboratory for Industrial Enzymes, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
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Nepal KK, Lee RP, Rezenom YH, Watanabe CMH. Probing the Role of N-Acetyl-glutamyl 5-Phosphate, an Acyl Phosphate, in the Construction of the Azabicycle Moiety of the Azinomycins. Biochemistry 2015; 54:4415-8. [DOI: 10.1021/acs.biochem.5b00711] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Keshav K. Nepal
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Rachel P. Lee
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Yohannes H. Rezenom
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Coran M. H. Watanabe
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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The role of ARGR repressor regulation on L-arginine production in Corynebacterium crenatum. Appl Biochem Biotechnol 2013; 170:587-97. [PMID: 23564434 DOI: 10.1007/s12010-013-0212-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 03/20/2013] [Indexed: 01/28/2023]
Abstract
Corynebacterium crenatum SYA is an aerobic, Gram-positive, non-sporulating coryneform bacterium, and the mutant C. crenatum strain SYPA 5-5 can produce 30 g/l L-arginine under optimal culture conditions. In this study, the evolution of the cluster argCJBDFRGH (argC~H) involved in arginine biosynthesis in C. crenatum SYA, and SYPA 5-5 was investigated. Compared to the argR of its wild type C. crenatum SYA, a nucleotide substitution (C→T) within the argR gene of the mutant C. crenatum strain SYPA 5-5 was found. The inactivation of ARGR resulted in increased enzyme activities involved in L-arginine biosynthesis and increased L-arginine production in C. crenatum. In contrast, constructing an overexpressing argR C. crenatum/pTR, a complete and functional ARGR decreased the expression of enzymes, depressed transcriptional level of the argC~H cluster, and reduced the production of L-arginine in C. crenatum. It was thus evident that the inactivation of an ARGR suppressor could relieve a bottleneck in downstream steps of the L-arginine biosynthetic pathway, providing a good strategy for improving L-arginine production.
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Xu M, Rao Z, Yang J, Xia H, Dou W, Jin J, Xu Z. Heterologous and homologous expression of the arginine biosynthetic argC~H cluster from Corynebacterium crenatum for improvement of l-arginine production. ACTA ACUST UNITED AC 2012; 39:495-502. [DOI: 10.1007/s10295-011-1042-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Accepted: 09/27/2011] [Indexed: 11/29/2022]
Abstract
Abstract
The genes involved in l-arginine biosynthesis in Corynebacterium crenatum are organized as the argCJBDFRGH cluster like in Corynebacterium glutamicum. However, the argC~H cluster of the C. crenatum SYPA 5-5, which is an industrialized l-arginine producer, had a lethal mutation occurring in the ArgR repressor encoding gene. The argC~H cluster with an inactive argR was overexpressed in E. coli and C. crenatum. In the recombinant E. coli JM109 enzyme activities were increased, and more l-arginine was found in the supernatants from l-glutamine. When the argC~H cluster was overexpressed in C. crenatum under its native promoter Parg, l-arginine production was increased by 24.9%, but the presence of the recombinant plasmid pJC-9039 had a negative effect on cell growth. Surprisingly, the DO value of the recombinant strain dropped gently and stayed at a lower level from 24 h to the end of fermentation. The results demonstrated an increasing utilization of oxygen and the distinct enhancement of unit cell l-arginine yields with the cluster argC~H-bearing in C. crenatum SYPA-9039. This study provides a kind of Corynebacteria with improved l-arginine-producing ability and an efficient elevation for producing amino acid. Moreover, the promoter Parg would be used as a valid promoter to express objective genes for metabolic engineering in Corynebacteria.
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Affiliation(s)
- Meijuan Xu
- grid.258151.a 0000000107081323 The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology Jiangnan University 214122 Wuxi Jiangsu Province People’s Republic of China
| | - Zhiming Rao
- grid.258151.a 0000000107081323 The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology Jiangnan University 214122 Wuxi Jiangsu Province People’s Republic of China
| | - Juan Yang
- grid.258151.a 0000000107081323 The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology Jiangnan University 214122 Wuxi Jiangsu Province People’s Republic of China
| | - Haifeng Xia
- grid.258151.a 0000000107081323 The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology Jiangnan University 214122 Wuxi Jiangsu Province People’s Republic of China
| | - Wenfang Dou
- grid.258151.a 0000000107081323 Laboratory of Pharmaceutical Engineering, School of Medicine and Pharmaceutics Jiangnan University 214122 Wuxi People’s Republic of China
| | - Jian Jin
- grid.258151.a 0000000107081323 Laboratory of Pharmaceutical Engineering, School of Medicine and Pharmaceutics Jiangnan University 214122 Wuxi People’s Republic of China
| | - Zhenghong Xu
- grid.258151.a 0000000107081323 Laboratory of Pharmaceutical Engineering, School of Medicine and Pharmaceutics Jiangnan University 214122 Wuxi People’s Republic of China
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Signal-transduction protein P(II) from Synechococcus elongatus PCC 7942 senses low adenylate energy charge in vitro. Biochem J 2011; 440:147-56. [PMID: 21774788 DOI: 10.1042/bj20110536] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
P(II) proteins belong to a family of highly conserved signal-transduction proteins that occurs widely in bacteria, archaea and plants. They respond to the central metabolites ATP, ADP and 2-OG (2-oxoglutarate), and control enzymes, transcription factors and transport proteins involved in nitrogen metabolism. In the present study, we examined the effect of ADP on in vitro P(II)-signalling properties for the cyanobacterium Synechococcus elongatus, a model for oxygenic phototrophic organisms. Different ADP/ATP ratios strongly affected the properties of P(II) signalling. Increasing ADP antagonized the binding of 2-OG and directly affected the interactions of P(II) with its target proteins. The resulting P(II)-signalling properties indicate that, in mixtures of ADP and ATP, P(II) trimers are occupied by mixtures of adenylate nucleotides. Binding and kinetic activation of NAGK (N-acetyl-L-glutamate kinase), the controlling enzyme of arginine biosynthesis, by P(II) was weakened by ADP, but relief from arginine inhibition remained unaffected. On the other hand, ADP enhanced the binding of P(II) to PipX, a co-activator of the transcription factor NtcA and, furthermore, antagonized the inhibitory effect of 2-OG on P(II)-PipX interaction. These results indicate that S. elongatus P(II) directly senses the adenylate energy charge, resulting in target-dependent differential modification of the P(II)-signalling properties.
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Bai L, Chang M, Shan J, Jiang R, Zhang Y, Zhang R, Li Y. Identification and characterization of a novel spermidine/spermine acetyltransferase encoded by gene ste26 from Streptomyces sp. 139. Biochimie 2011; 93:1401-7. [DOI: 10.1016/j.biochi.2011.04.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Accepted: 04/20/2011] [Indexed: 10/18/2022]
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