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Molecular basis of function and the unusual antioxidant activity of a cyanobacterial cysteine desulfurase. Biochem J 2017; 474:2435-2447. [PMID: 28592683 DOI: 10.1042/bcj20170290] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 06/06/2017] [Accepted: 06/07/2017] [Indexed: 11/17/2022]
Abstract
Cysteine desulfurases, which supply sulfur for iron-sulfur cluster biogenesis, are broadly distributed in all phyla including cyanobacteria, the progenitors of plant chloroplasts. The SUF (sulfur utilization factor) system is responsible for Fe-S cluster biosynthesis under stress. The suf operon from cyanobacterium Anabaena PCC 7120 showed the presence of a cysteine desulfurase, sufS (alr2495), but not the accessory sulfur-accepting protein (SufE). However, an open reading frame (alr3513) encoding a SufE-like protein (termed AsaE, Anabaena sulfur acceptor E) was found at a location distinct from the suf operon. The purified SufS protein existed as a pyridoxal 5' phosphate (PLP)-containing dimer with a relatively low desulfurase activity. Interestingly, in the presence of the AsaE protein, the catalytic efficiency of this reaction increased 10-fold. In particular, for sulfur mobilization, the AsaE protein partnered only SufS and not other cysteine desulfurases from Anabaena. The SufS protein was found to physically interact with the AsaE protein, demonstrating that AsaE was indeed the missing partner of Anabaena SufS. The conserved cysteine of the SufS or the AsaE protein was essential for activity but not for their physical association. Curiously, overexpression of the SufS protein in Anabaena caused reduced formation of reactive oxygen species on exposure to hydrogen peroxide (H2O2), resulting in superior oxidative stress tolerance to the oxidizing agent when compared with the wild-type strain. Overall, the results highlight the functional interaction between the two proteins that mediate sulfur mobilization, in the cyanobacterial SUF pathway, and further reveal that overexpression of SufS can protect cyanobacteria from oxidative stress.
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Yingping F, Lemeille S, González A, Risoul V, Denis Y, Richaud P, Lamrabet O, Fillat MF, Zhang CC, Latifi A. The Pkn22 Ser/Thr kinase in Nostoc PCC 7120: role of FurA and NtcA regulators and transcript profiling under nitrogen starvation and oxidative stress. BMC Genomics 2015. [PMID: 26220092 PMCID: PMC4518582 DOI: 10.1186/s12864-015-1703-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background The filamentous cyanobacterium Nostoc sp. strain PCC 7120 can fix N2 when combined nitrogen is not available. Furthermore, it has to cope with reactive oxygen species generated as byproducts of photosynthesis and respiration. We have previously demonstrated the synthesis of Ser/Thr kinase Pkn22 as an important survival response of Nostoc to oxidative damage. In this study we wished to investigate the possible involvement of this kinase in signalling peroxide stress and nitrogen deprivation. Results Quantitative RT-PCR experiments revealed that the pkn22 gene is induced in response to peroxide stress and to combined nitrogen starvation. Electrophoretic motility assays indicated that the pkn22 promoter is recognized by the global transcriptional regulators FurA and NtcA. Transcriptomic analysis comparing a pkn22-insertion mutant and the wild type strain indicated that this kinase regulates genes involved in important cellular functions such as photosynthesis, carbon metabolism and iron acquisition. Since metabolic changes may lead to oxidative stress, we investigated whether this is the case with nitrogen starvation. Our results rather invalidate this hypothesis thereby suggesting that the function of Pkn22 under nitrogen starvation is independent of its role in response to peroxide stress. Conclusions Our analyses have permitted a more complete functional description of Ser/Thr kinase in Nostoc. We have decrypted the transcriptional regulation of the pkn22 gene, and analysed the whole set of genes under the control of this kinase in response to the two environmental changes often encountered by cyanobacteria in their natural habitat: oxidative stress and nitrogen deprivation. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1703-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Fan Yingping
- Aix-Marseille University and CNRS, Laboratoire de Chimie Bactérienne - UMR7283, IMM, 31 Chemin Joseph Aiguier, 13402, Marseille cedex 20, France.
| | - Sylvain Lemeille
- Department of Microbiology and Molecular Medicine, CMU, Medical Faculty, University of Geneva, Genève, 1211, Switzerland.
| | - Andrés González
- Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, 50009, Zaragoza, Spain.
| | - Véronique Risoul
- Aix-Marseille University and CNRS, Laboratoire de Chimie Bactérienne - UMR7283, IMM, 31 Chemin Joseph Aiguier, 13402, Marseille cedex 20, France.
| | - Yann Denis
- Plate-forme Transcriptome FR3479, IMM-CNRS, Marseille, France.
| | - Pierre Richaud
- CEA, DSV, IBEB, SBVME, Saint-Paul-lez-Durance, F-13108, France. .,CNRS, UMR 7265 Biol Veget & Microbiol Environ, Saint-Paul-lez-Durance, F-13108, France. .,Aix Marseille Université, BVME UMR7265, Marseille, F-13284, France.
| | - Otmane Lamrabet
- Aix-Marseille University and CNRS, Laboratoire de Chimie Bactérienne - UMR7283, IMM, 31 Chemin Joseph Aiguier, 13402, Marseille cedex 20, France.
| | - Maria F Fillat
- Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, 50009, Zaragoza, Spain.
| | - Cheng-Cai Zhang
- Aix-Marseille University and CNRS, Laboratoire de Chimie Bactérienne - UMR7283, IMM, 31 Chemin Joseph Aiguier, 13402, Marseille cedex 20, France.
| | - Amel Latifi
- Aix-Marseille University and CNRS, Laboratoire de Chimie Bactérienne - UMR7283, IMM, 31 Chemin Joseph Aiguier, 13402, Marseille cedex 20, France.
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Yingping F, Lemeille S, Talla E, Janicki A, Denis Y, Zhang CC, Latifi A. Unravelling the cross-talk between iron starvation and oxidative stress responses highlights the key role of PerR (alr0957) in peroxide signalling in the cyanobacterium Nostoc PCC 7120. ENVIRONMENTAL MICROBIOLOGY REPORTS 2014; 6:468-475. [PMID: 25646537 DOI: 10.1111/1758-2229.12157] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The cyanobacterial phylum includes oxygenic photosynthetic prokaryotes of a wide variety of morphologies, metabolisms and ecologies. Their adaptation to their various ecological niches is mainly achieved by sophisticated regulatory mechanisms and depends on a fine cross-talk between them. We assessed the global transcriptomic response of the filamentous cyanobacterium Nostoc PCC 7120 to iron starvation and oxidative stress. More than 20% of the differentially expressed genes in response to iron stress were also responsive to oxidative stress. These transcripts include antioxidant proteins-encoding genes that confirms that iron depletion leads to reactive oxygen accumulation. The activity of the Fe-superoxide dismutase was not significantly decreased under iron starvation, indicating that the oxidative stress generated under iron deficiency is not a consequence of (SOD) deficiency. The transcriptional data indicate that the adaptation of Nostoc to iron-depleted conditions displays important differences with what has been shown in unicellular cyanobacteria. While the FurA protein that regulates the response to iron deprivation has been well characterized in Nostoc, the regulators in charge of the oxidative stress response are unknown. Our study indicates that the alr0957 (perR) gene encodes the master regulator of the peroxide stress. PerR is a peroxide-sensor repressor that senses peroxide by metal-catalysed oxidation.
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Hidese R, Mihara H, Esaki N. Bacterial cysteine desulfurases: versatile key players in biosynthetic pathways of sulfur-containing biofactors. Appl Microbiol Biotechnol 2011; 91:47-61. [DOI: 10.1007/s00253-011-3336-x] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2011] [Revised: 04/13/2011] [Accepted: 04/13/2011] [Indexed: 11/29/2022]
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