CopM is a novel copper-binding protein involved in copper resistance in Synechocystis sp. PCC 6803

Copper resistance system in the cyanobacterium Synechocystis sp. PCC 6803 comprises two operons, copMRS and copBAC, which are expressed in response to copper in the media. copBAC codes for a heavy-metal efflux–resistance nodulation and division (HME-RND) system, while copMRS codes for a protein of unknown function, CopM, and a two-component system CopRS, which controls the expression of these two operons. Here, we report that CopM is a periplasmic protein able to bind Cu(I) with high affinity (KD ∼3 × 10−16). Mutants lacking copM showed a sensitive copper phenotype similar to mutants affected in copB, but lower than mutants of the two-component system CopRS, suggesting that CopBAC and CopM constitute two independent resistance mechanisms. Moreover, constitutive expression of copM is able to partially suppress the copper sensitivity of the copR mutant strain, pointing out that CopM per se is able to confer copper resistance. Furthermore, constitutive expression of copM was able to reduce total cellular copper content of the copR mutant to the levels determined in the wild-type (WT) strain. Finally, CopM was localized not only in the periplasm but also in the extracellular space, suggesting that CopM can also prevent copper accumulation probably by direct copper binding outside the cell.España, Ministerio de Economía y Competitividad BFU2010–15708España, Ministerio de Economía y Competitividad BFU2013–41712-

Redox control of copper homeostasis in cyanobacteria

Copper is essential for all living organisms but is toxic when present in excess. Therefore organisms have developed homeostatic mechanism to tightly regulate its cellular concentration. In a recent study we have shown that CopRS two-component system is essential for copper resistance in the cyanobacterium Synechocystis sp PCC 6803. This two-component regulates expression of a heavy-metal RND type copper efflux system (encoded by copBAC) as well as its own expression (in the copMRS operon) in response to an excess of copper in the media. We have also observed that both operons are induced under condition that reduces the photosynthetic electron flow and this induction depends of the presence of the copper-protein, plastocyanin. These findings, together with CopS localization to the thylakoid membrane and its periplasmic domain being able to bind copper directly, suggest that CopS could be involved in copper detection in both the periplasm and the thylakoid lume

Metals in Cyanobacteria: analysis of the copper, nickel, cobalt and arsenic homeostasis mechanisms

Traces of metal are required for fundamental biochemical processes, such as photosynthesis and respiration. Cyanobacteria metal homeostasis acquires an important role because the photosynthetic machinery imposes a high demand for metals, making them a limiting factor for cyanobacteria, especially in the open oceans. On the other hand, in the last two centuries, the metal concentrations in marine environments and lake sediments have increased as a result of several industrial activities. In all cases, cells have to tightly regulate uptake to maintain their intracellular concentrations below toxic levels. Mechanisms to obtain metal under limiting conditions and to protect cells from an excess of metals are present in cyanobacteria. Understanding metal homeostasis in cyanobacteria and the proteins involved will help to evaluate the use of these microorganisms in metal bioremediation. Furthermore, it will also help to understand how metal availability impacts primary production in the oceans. In this review, we will focus on copper, nickel, cobalt and arsenic (a toxic metalloid) metabolism, which has been mainly analyzed in model cyanobacterium Synechocystis sp. PCC 6803.info:eu-repo/semantics/publishedVersio

eggNOG 6.0: enabling comparative genomics across 12 535 organisms

The eggNOG (evolutionary gene genealogy Non-supervised Orthologous Groups) database is a bioinformatics resource providing orthology data and comprehensive functional information for organisms from all domains of life. Here, we present a major update of the database and website (version 6.0), which increases the number of covered organisms to 12 535 reference species, expands functional annotations, and implements new functionality. In total, eggNOG 6.0 provides a hierarchy of over 17M orthologous groups (OGs) computed at 1601 taxonomic levels, spanning 10 756 bacterial, 457 archaeal and 1322 eukaryotic organisms. OGs have been thoroughly annotated using recent knowledge from functional databases, including KEGG, Gene Ontology, UniProtKB, BiGG, CAZy, CARD, PFAM and SMART. eggNOG also offers phylogenetic trees for all OGs, maximising utility and versatility for end users while allowing researchers to investigate the evolutionary history of speciation and duplication events as well as the phylogenetic distribution of functional terms within each OG. Furthermore, the eggNOG 6.0 website contains new functionality to mine orthology and functional data with ease, including the possibility of generating phylogenetic profiles for multiple OGs across species or identifying single-copy OGs at custom taxonomic levels. eggNOG 6.0 is available at http://eggnog6.embl.de

eggNOG 6.0: enabling comparative genomics across 12 535 organisms

6 Pág.The eggNOG (evolutionary gene genealogy Non-supervised Orthologous Groups) database is a bioinformatics resource providing orthology data and comprehensive functional information for organisms from all domains of life. Here, we present a major update of the database and website (version 6.0), which increases the number of covered organisms to 12 535 reference species, expands functional annotations, and implements new functionality. In total, eggNOG 6.0 provides a hierarchy of over 17M orthologous groups (OGs) computed at 1601 taxonomic levels, spanning 10 756 bacterial, 457 archaeal and 1322 eukaryotic organisms. OGs have been thoroughly annotated using recent knowledge from functional databases, including KEGG, Gene Ontology, UniProtKB, BiGG, CAZy, CARD, PFAM and SMART. eggNOG also offers phylogenetic trees for all OGs, maximising utility and versatility for end users while allowing researchers to investigate the evolutionary history of speciation and duplication events as well as the phylogenetic distribution of functional terms within each OG. Furthermore, the eggNOG 6.0 website contains new functionality to mine orthology and functional data with ease, including the possibility of generating phylogenetic profiles for multiple OGs across species or identifying single-copy OGs at custom taxonomic levels. eggNOG 6.0 is available at http://eggnog6.embl.de.National Programme for Fostering Excellence in Scientific and Technical Research [PGC2018-098073-A-I00 MCIU/AEI/FEDER, UE to J.H.-C., J.G.-L.]; Chan Zuckerberg Initiative DAF [2020-218584]; Silicon Valley Community Foundation (to J.B. and J.H.C.); Severo Ochoa Centres of Excellence Programme from the State Research Agency (AEI) of Spain [SEV-2016–0672 (2017–2021) to C.P.C.]; Research Technical Support Staff Aid [PTA2019-017593-I/AEI/10.13039/501100011033 to A.H.P.]; Novo Nordisk Foundation [NNF14CC0001 to R.K., L.J.J.]; SIB Swiss Institute of Bioinformatics (to D.S. and C.vM.). Funding for open access charge: Institutional CSIC and EMBL agreements.Peer reviewe

Towards the biogeography of prokaryotic genes

Funding was provided by the European Union’s Horizon 2020 Research and Innovation Programme (grant 686070: DD-DeCaF to P.B.) and Marie Skłodowska-Curie Actions (grant 713673 to A.R.d.R.), the European Research Council (ERC) MicrobioS (ERC-AdG-669830 to P.B.), JTC project jumpAR (01KI1706 to P.B.), a BMBF Grant (grant 031L0181A: LAMarCK to P.B.), the European Molecular Biology Laboratory (P.B.), the ETH and Helmut Horten Foundation (S.S.), the National Key R&D Program of China (grant 2020YFA0712403 to X.-M.Z.), (grant 61932008 to X.-M.Z.; grant 61772368 to X.-M.Z.; grant 31950410544 to L.P.C.), the Shanghai Municipal Science and Technology Major Project (grant 2018SHZDZX01 to X.-M.Z. and L.P.C.) and Zhangjiang Lab (X.-M.Z. and L.P.C.), the International Development Research Centre (grant 109304, EMBARK under the JPI AMR framework; to L.P.C.), la Caixa Foundation (grant 100010434, fellowship code LCF/BQ/DI18/11660009 to A.R.d.R.), the Severo Ochoa Program for Centres of Excellence in R&D from the Agencia Estatal de Investigación of Spain (grant SEV-2016-0672 (2017–2021) to C.P.C.), the Ministerio de Ciencia, Innovación y Universidades (grant PGC2018-098073-A-I00 MCIU/AEI/FEDER to J.H.-C. and J.G.-L.), the Innovation Fund Denmark (grant 4203-00005B, PNM), the Biotechnology and Biological Sciences research Council (BBSrC) Gut MicroInstitute Strategic Programmebes and Health BB/r012490/1 and its constituent project BBS/e/F/000Pr10355 (F.H.). R.A. is a member of the Collaboration for joint PhD degree between EMBL and Heidelberg University, Faculty of Biosciences.Peer reviewe

CopM is a novel copper-binding protein involved in copper resistance in Synechocystis sp. PCC 6803.

Copper resistance system in the cyanobacterium Synechocystis sp. PCC 6803 comprises two operons, copMRS and copBAC, which are expressed in response to copper in the media. copBAC codes for a heavy-metal efflux-resistance nodulation and division (HME-RND) system, while copMRS codes for a protein of unknown function, CopM, and a two-component system CopRS, which controls the expression of these two operons. Here, we report that CopM is a periplasmic protein able to bind Cu(I) with high affinity (KD ~3 × 10(-16) ). Mutants lacking copM showed a sensitive copper phenotype similar to mutants affected in copB, but lower than mutants of the two-component system CopRS, suggesting that CopBAC and CopM constitute two independent resistance mechanisms. Moreover, constitutive expression of copM is able to partially suppress the copper sensitivity of the copR mutant strain, pointing out that CopM per se is able to confer copper resistance. Furthermore, constitutive expression of copM was able to reduce total cellular copper content of the copR mutant to the levels determined in the wild-type (WT) strain. Finally, CopM was localized not only in the periplasm but also in the extracellular space, suggesting that CopM can also prevent copper accumulation probably by direct copper binding outside the cell.Peer reviewe

Table_2_Exploring the sediment-associated microbiota of the Mar Menor coastal lagoon.xlsx

The full text of this article can be freely accessed on the publisher's website

DataSheet_1_Exploring the sediment-associated microbiota of the Mar Menor coastal lagoon.docx

The full text of this article can be freely accessed on the publisher's website

Redox control of copper homeostasis in cyanobacteria.

Copper is essential for all living organisms but is toxic when present in excess. Therefore organisms have developed homeostatic mechanism to tightly regulate its cellular concentration. In a recent study we have shown that CopRS two-component system is essential for copper resistance in the cyanobacterium Synechocystis sp PCC 6803. This two-component regulates expression of a heavy-metal RND type copper efflux system (encoded by copBAC) as well as its own expression (in the copMRS operon) in response to an excess of copper in the media. We have also observed that both operons are induced under condition that reduces the photosynthetic electron flow and this induction depends of the presence of the copper-protein, plastocyanin. These findings, together with CopS localization to the thylakoid membrane and its periplasmic domain being able to bind copper directly, suggest that CopS could be involved in copper detection in both the periplasm and the thylakoid lumen.Peer Reviewe