1
|
Lücking D, Alarcón-Schumacher T, Erdmann S. Distribution and Implications of Haloarchaeal Plasmids Disseminated in Self-Encoded Plasmid Vesicles. Microorganisms 2023; 12:5. [PMID: 38276173 PMCID: PMC10818511 DOI: 10.3390/microorganisms12010005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 12/14/2023] [Accepted: 12/16/2023] [Indexed: 01/27/2024] Open
Abstract
Even though viruses and plasmids are both drivers of horizontal gene transfer, they differ fundamentally in their mode of transfer. Virus genomes are enclosed in virus capsids and are not dependent on cell-to-cell contacts for their dissemination. In contrast, the transfer of plasmids most often requires physical contact between cells. However, plasmid pR1SE of Halorubrum lacusprofundi is disseminated between cells, independent of cell-cell contacts, in specialized membrane vesicles that contain plasmid proteins. In this study, we searched for pR1SE-like elements in public databases and a metagenomics dataset from Australian salt lakes and identified 40 additional pR1SE-like elements in hypersaline environments worldwide. Herein, these elements are named apHPVs (archaeal plasmids of haloarchaea potentially transferred in plasmid vesicles). They share two sets of closely related proteins with conserved synteny, strongly indicating an organization into different functional clusters. We find that apHPVs, besides transferring themselves, have the potential to transfer large fragments of DNA between host cells, including virus defense systems. Most interestingly, apHPVs likely play an important role in the evolution of viruses and plasmids in haloarchaea, as they appear to recombine with both of them. This further supports the idea that plasmids and viruses are not distinct but closely related mobile genetic elements.
Collapse
Affiliation(s)
| | | | - Susanne Erdmann
- Max-Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany
| |
Collapse
|
2
|
Gebhard LJ, Vershinin Z, Alarcón-Schumacher T, Eichler J, Erdmann S. Influence of N-Glycosylation on Virus-Host Interactions in Halorubrum lacusprofundi. Viruses 2023; 15:1469. [PMID: 37515157 PMCID: PMC10384203 DOI: 10.3390/v15071469] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 06/23/2023] [Accepted: 06/26/2023] [Indexed: 07/30/2023] Open
Abstract
N-glycosylation is a post-translational modification of proteins that occurs across all three domains of life. In Archaea, N-glycosylation is crucial for cell stability and motility, but importantly also has significant implications for virus-host interactions. While some archaeal viruses present glycosylated proteins or interact with glycosylated host proteins, the direct influence of N-glycosylation on archaeal virus-host interactions remains to be elucidated. In this study, we generated an N-glycosylation-deficient mutant of Halorubrum lacusprofundi, a halophilic archaeon commonly used to study cold adaptation, and examined the impact of compromised N-glycosylation on the infection dynamics of two very diverse viruses. While compromised N-glycosylation had no influence on the life cycle of the head-tailed virus HRTV-DL1, we observed a significant effect on membrane-containing virus HFPV-1. Both intracellular genome numbers and extracellular virus particle numbers of HFPV-1 were increased in the mutant strain, which we attribute to instability of the surface-layer which builds the protein envelope of the cell. When testing the impact of compromised N-glycosylation on the life cycle of plasmid vesicles, specialized membrane vesicles that transfer a plasmid between host cells, we determined that plasmid vesicle stability is strongly dependent on the host glycosylation machinery. Our study thus provides important insight into the role of N-glycosylation in virus-host interactions in Archaea, while pointing to how this influence strongly differs amongst various viruses and virus-like elements.
Collapse
Affiliation(s)
- L Johanna Gebhard
- Max Planck Institute for Marine Microbiology, Archaeal Virology, 28359 Bremen, Germany
| | - Zlata Vershinin
- Department of Life Sciences, Ben-Gurion University of the Negev, Beersheva 84105, Israel
| | | | - Jerry Eichler
- Department of Life Sciences, Ben-Gurion University of the Negev, Beersheva 84105, Israel
| | - Susanne Erdmann
- Max Planck Institute for Marine Microbiology, Archaeal Virology, 28359 Bremen, Germany
| |
Collapse
|
3
|
Alarcón-Schumacher T, Guajardo-Leiva S, Martinez-Garcia M, Díez B. Ecogenomics and Adaptation Strategies of Southern Ocean Viral Communities. mSystems 2021; 6:e0039621. [PMID: 34374561 PMCID: PMC8407431 DOI: 10.1128/msystems.00396-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 07/21/2021] [Indexed: 11/20/2022] Open
Abstract
The Southern Ocean (SO) represents up to one-fifth of the total carbon drawdown worldwide. Intense selective pressures (low temperature, high UV radiation, and strong seasonality) and physical isolation characterize the SO, serving as a "natural" laboratory for the study of ecogenomics and unique adaptations of endemic viral populations. Here, we report 2,416 novel viral genomes from the SO, obtained from newly sequenced viral metagenomes in combination with mining of publicly available data sets, which represents a 25% increase in the SO viral genomes reported to date. They comprised 567 viral clusters (defined as approximately genus-level groups), with 186 genera endemic to the SO, demonstrating that the SO viral community is predominantly constituted by a large pool of genetically divergent viral species from widespread viral families. The predicted proteome from SO viruses revealed that several protein clusters related to cold-shock-event responses and quorum-sensing mechanisms involved in the lysogenic-lytic cycle shift decision were under positive selection, which is ultimately important for fine adaptation of viral populations in response to the strong selective pressures of the SO. Finally, changes in the hydrophobicity patterns and amino acid frequencies suggested marked temperature-driven genetic selection of the SO viral proteome. Our data provide valuable insights into how viruses adapt and remain successful in this extreme polar marine environment. IMPORTANCE Viruses are the most abundant biologic entities in marine systems and strongly influence the microbial community composition and diversity. However, little is known about viral communities' adaptation and diversification in the ocean. In this work, we take advantage of the geographical isolation and the intense selective pressures of the SO, to which viruses are exposed, to identify potential viral adaptations due to positive environmental selection and dispersal limitation. To that end, we recovered more than two thousand novel viral genomes, revealing a high degree of divergence in these SO endemic communities. Furthermore, we describe remarkable viral adaptations in amino acid frequencies and accessory proteins related to cold shock response and quorum sensing that allow them to thrive at lower temperatures. Consequently, our work greatly expands the understanding of the diversification of the viral communities of the SO and their particular adaptations to low temperatures.
Collapse
Affiliation(s)
- Tomás Alarcón-Schumacher
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago, Chile
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Sergio Guajardo-Leiva
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Manuel Martinez-Garcia
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Carretera San Vicente del Raspeig, San Vicente del Raspeig, Alicante, Spain
| | - Beatriz Díez
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago, Chile
- Center for Climate and Resilience Research (CR) 2, Santiago, Chile
- Center for Genome Regulation (CGR), Santiago, Chile
| |
Collapse
|
4
|
Alcorta J, Alarcón-Schumacher T, Salgado O, Díez B. Taxonomic Novelty and Distinctive Genomic Features of Hot Spring Cyanobacteria. Front Genet 2020; 11:568223. [PMID: 33250920 PMCID: PMC7674949 DOI: 10.3389/fgene.2020.568223] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 10/15/2020] [Indexed: 01/06/2023] Open
Abstract
Several cyanobacterial species are dominant primary producers in hot spring microbial mats. To date, hot spring cyanobacterial taxonomy, as well as the evolution of their genomic adaptations to high temperatures, are poorly understood, with genomic information currently available for only a few dominant genera, including Fischerella and Synechococcus. To address this knowledge gap, the present study expands the genomic landscape of hot spring cyanobacteria and traces the phylum-wide genomic consequences of evolution in high temperature environments. From 21 globally distributed hot spring metagenomes, with temperatures between 32 and 75°C, 57 medium- and high-quality cyanobacterial metagenome-assembled genomes were recovered, representing taxonomic novelty for 1 order, 3 families, 15 genera and 36 species. Comparative genomics of 93 hot spring genomes (including the 57 metagenome-assembled genomes) and 66 non-thermal genomes, showed that the former have smaller genomes and a higher GC content, as well as shorter proteins that are more hydrophilic and basic, when compared to the non-thermal genomes. Additionally, the core accessory orthogroups from the hot spring genomes of some genera had a greater abundance of functional categories, such as inorganic ion metabolism, translation and post-translational modifications. Moreover, hot spring genomes showed increased abundances of inorganic ion transport and amino acid metabolism, as well as less replication and transcription functions in the protein coding sequences. Furthermore, they showed a higher dependence on the CRISPR-Cas defense system against exogenous nucleic acids, and a reduction in secondary metabolism biosynthetic gene clusters. This suggests differences in the cyanobacterial response to environment-specific microbial communities. This phylum-wide study provides new insights into cyanobacterial genomic adaptations to a specific niche where they are dominant, which could be essential to trace bacterial evolution pathways in a warmer world, such as the current global warming scenario.
Collapse
Affiliation(s)
- Jaime Alcorta
- Department of Molecular Genetics and Microbiology, Biological Sciences Faculty, Pontifical Catholic University of Chile, Santiago, Chile
| | - Tomás Alarcón-Schumacher
- Department of Molecular Genetics and Microbiology, Biological Sciences Faculty, Pontifical Catholic University of Chile, Santiago, Chile
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Oscar Salgado
- Department of Molecular Genetics and Microbiology, Biological Sciences Faculty, Pontifical Catholic University of Chile, Santiago, Chile
- Max Planck Institute for Marine Microbiology, Bremen, Germany
- Laboratorio de Bioinformática, Facultad de Educación, Universidad Adventista de Chile, Chillán, Chile
| | - Beatriz Díez
- Department of Molecular Genetics and Microbiology, Biological Sciences Faculty, Pontifical Catholic University of Chile, Santiago, Chile
- Center for Climate and Resilience Research (CR)2, University of Chile, Santiago, Chile
| |
Collapse
|
5
|
Alcamán-Arias ME, Farías L, Verdugo J, Alarcón-Schumacher T, Díez B. Microbial activity during a coastal phytoplankton bloom on the Western Antarctic Peninsula in late summer. FEMS Microbiol Lett 2019; 365:4961137. [PMID: 29788084 DOI: 10.1093/femsle/fny090] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 04/03/2018] [Indexed: 12/19/2022] Open
Abstract
Phytoplankton biomass during the austral summer is influenced by freezing and melting cycles as well as oceanographic processes that enable nutrient redistribution in the West Antarctic Peninsula (WAP). Microbial functional capabilities, metagenomic and metatranscriptomic activities as well as inorganic 13C- and 15N-assimilation rates were studied in the surface waters of Chile Bay during two contrasting summer periods in 2014. Concentrations of Chlorophyll a (Chla) varied from 0.3 mg m-3 in February to a maximum of 2.5 mg m-3 in March, together with a decrease in nutrients; however, nutrients were never depleted. The microbial community composition remained similar throughout both sampling periods; however, microbial abundance and activity changed with Chla levels. An increased biomass of Bacillariophyta, Haptophyceae and Cryptophyceae was observed along with night-grazing activity of Dinophyceae and ciliates (Alveolates). During high Chla conditions, HCO3- uptake rates during daytime incubations increased 5-fold (>2516 nmol C L-1 d-1), and increased photosynthetic transcript numbers that were mainly associated with cryptophytes; meanwhile night time NO3- (>706 nmol N L-1 d-1) and NH4+ (41.7 nmol N L-1 d-1) uptake rates were 2- and 3-fold higher, respectively, due to activity from Alpha-/Gammaproteobacteria and Bacteroidetes (Flavobacteriia). Due to a projected acceleration in climate change in the WAP, this information is valuable for predicting the composition and functional changes in Antarctic microbial communities.
Collapse
Affiliation(s)
- María E Alcamán-Arias
- Department of Oceanography, Universidad de Concepción, 4070386 Concepción, Chile.,Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, 6513677 Santiago, Chile.,Center for Climate and Resilience Research (CR) 2, Universidad de Chile, 8370448 Santiago, Chile
| | - Laura Farías
- Department of Oceanography, Universidad de Concepción, 4070386 Concepción, Chile.,Center for Climate and Resilience Research (CR) 2, Universidad de Chile, 8370448 Santiago, Chile
| | - Josefa Verdugo
- Alfred-Wegener-Institute Helmholtz-Centre for Polar and Marine Research, 27570 Bremerhaven, Germany
| | - Tomás Alarcón-Schumacher
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, 6513677 Santiago, Chile
| | - Beatriz Díez
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, 6513677 Santiago, Chile.,Center for Climate and Resilience Research (CR) 2, Universidad de Chile, 8370448 Santiago, Chile
| |
Collapse
|
6
|
Alarcón-Schumacher T, Guajardo-Leiva S, Antón J, Díez B. Elucidating Viral Communities During a Phytoplankton Bloom on the West Antarctic Peninsula. Front Microbiol 2019; 10:1014. [PMID: 31139164 PMCID: PMC6527751 DOI: 10.3389/fmicb.2019.01014] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 04/24/2019] [Indexed: 01/16/2023] Open
Abstract
In Antarctic coastal waters where nutrient limitations are low, viruses are expected to play a major role in the regulation of bloom events. Despite this, research in viral identification and dynamics is scarce, with limited information available for the Southern Ocean (SO). This study presents an integrative-omics approach, comparing variation in the viral and microbial active communities on two contrasting sample conditions from a diatom-dominated phytoplankton bloom occurring in Chile Bay in the West Antarctic Peninsula (WAP) in the summer of 2014. The known viral community, initially dominated by Myoviridae family (∼82% of the total assigned reads), changed to become dominated by Phycodnaviridae (∼90%), while viral activity was predominantly driven by dsDNA members of the Phycodnaviridae (∼50%) and diatom infecting ssRNA viruses (∼38%), becoming more significant as chlorophyll a increased. A genomic and phylogenetic characterization allowed the identification of a new viral lineage within the Myoviridae family. This new lineage of viruses infects Pseudoalteromonas and was dominant in the phage community. In addition, a new Phycodnavirus (PaV) was described, which is predicted to infect Phaeocystis antarctica, the main blooming haptophyte in the SO. This work was able to identify the changes in the main viral players during a bloom development and suggests that the changes observed in the virioplankton could be used as a model to understand the development and decay of blooms that occur throughout the WAP.
Collapse
Affiliation(s)
- Tomás Alarcón-Schumacher
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago, Chile.,Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Sergio Guajardo-Leiva
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Josefa Antón
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Alicante, Spain
| | - Beatriz Díez
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago, Chile.,Center for Climate and Resilience Research (CR2), University of Chile, Santiago, Chile
| |
Collapse
|
7
|
Fuentes S, Arroyo JI, Rodríguez-Marconi S, Masotti I, Alarcón-Schumacher T, Polz MF, Trefault N, De la Iglesia R, Díez B. Summer phyto- and bacterioplankton communities during low and high productivity scenarios in the Western Antarctic Peninsula. Polar Biol 2018. [DOI: 10.1007/s00300-018-2411-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|