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Vogel, Anne Ilse Maria; Winther-Larsen, Hanne Cecilie; Roos, Norbert; Lale, Rahmi & Hohmann-Marriott, Martin Frank
(2018).
A novel function of type IV pili in iron uptake in Synechococcus sp. PCC 7002.
Show summary
Iron is abundant in the Earth’s crust, but in marine environments, iron is often the limiting micronutrient for cyanobacterial growth. Marine cyanobacteria such as Synechococcus sp. PCC 7002 (hereafter Synechococcus) require iron for their photosynthetic machinery, especially Photosystem I, and have therefore developed efficient iron acquisition strategies. Recent research on type IV pili suggests that these so-called “nanowires” can increase metal bioavailability by facilitating reduction of extracellular electron acceptors such as iron oxides (1,2). These pili consist of tightly stacked pilA1 proteins and seem to have conductive properties (1).
We deleted the gene encoding pilA1 in Synechococcus and studied the growth of the deletion strain on different iron minerals with varying bioavailability. The ΔpilA1 strain shows reduced growth compared to wildtype Synechococcus when grown on iron oxides with low bioavailability.
We analyzed pili expression with SEM, TEM and mass spectrometry. Our results indicate a clear effect of pilA1 deletion on the expression of alternative pilins.
Finally, we assessed the state of the photosynthetic complexes by spectroscopic methods. Spectral analysis of the ΔpilA1 strain indicate changes of the photosynthetic complexes consistent with iron stress.
Our results indicate a novel function of type IV pili in iron acquisition in marine cyanobacteria. Heterologous pilA expression and deletion of genes involved in other parts of the external electron transport chain will further elucidate how intracellular electron transport is coupled to extracellular reduction.
(1) Gorby YA, Yanina S, McLean JS, et al (2006) Electrically conductive bacterial nanowires produced by Shewanella oneidensis strain MR-1 and other microorganisms. Proc Natl Acad Sci U S A 103:11358–63. doi: 10.1073/pnas.0604517103
(2) Lamb JJ, Hill RE, Eaton-Rye JJ, Hohmann-Marriott MF (2014) Functional role of PilA in iron acquisition in the cyanobacterium Synechocystis sp. PCC 6803. PLoS One 9:e105761. doi: 10.1371/journal.pone.0105761
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Vogel, Anne Ilse Maria; Winther-Larsen, Hanne Cecilie; Roos, Norbert; Lale, Rahmi & Hohmann-Marriott, Martin Frank
(2018).
Conductive Type IV pili play an important role for iron acquisition in the marine cyanobacterium Synechococcus sp. PCC 7002 .
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Vogel, Anne Ilse Maria; Winther-Larsen, Hanne Cecilie; Roos, Norbert; Lale, Rahmi & Hohmann-Marriott, Martin Frank
(2018).
Function of type IV pili in iron acquisition in Synechococcus sp. PCC 7002.
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Vogel, Anne Ilse Maria; Winther-Larsen, Hanne Cecilie; Roos, Norbert; Lale, Rahmi & Hohmann-Marriott, Martin Frank
(2018).
Function of type IV pili in iron acquisition in Synechococcus sp. PCC 7002.
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Vogel, Anne Ilse Maria; Winther-Larsen, Hanne Cecilie; Roos, Norbert; Lale, Rahmi & Hohmann-Marriott, Martin Frank
(2018).
Function of type IV pili in iron acquisition in Synechococcus sp. PCC 7002.
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Wessel, Øystein; Braaen, Stine; Alarcon, Marta; Haatveit, Hanne Merethe; Roos, Norbert & Markussen, Turhan
[Show all 9 contributors for this article]
(2017).
Infection with purified Piscine orthoreovirus demonstrates a causal relationship with heart and skeletal muscle inflammation in Atlantic salmon.
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Introduction:
Heart- and skeletal muscle inflammation (HSMI) is an emerging disease in Atlantic salmon (Salmo salar) farming. HSMI is associated with Piscine orthoreovirus (PRV) infection, but PRV is ubiquitous in farmed Atlantic salmon and thus present also in apparently healthy individuals. This has brought speculations if additional etiological factors are required, and experiments focusing on the causal relationship between PRV and HSMI are highly warranted.
Methodology:
A major bottleneck in PRV research has been the lack of cell lines that allow propagation of the virus. To bypass this, we propagated PRV in salmon, bled the fish at the peak of the infection, and purified virus particles from blood cells by gradient centrifugation. Electron microscopy, western blot and high-throughput sequencing all verified the purity of the viral particles. Two doses of purified PRV particles were inoculated into Atlantic salmon, which were cohabitated 50:50 with naïve individuals for eight weeks. PRV load and antiviral responses were examined by RT-qPCR, and histological analysis and immunostaining for PRV was performed in heart and muscle.
Results:
The purified virus replicated in inoculated fish, spread to naïve cohabitants, and induced histopathological changes consistent with HSMI. PRV specific staining was demonstrated in the pathological lesions. A dose-dependent response was observed; a high dose of virus gave earlier peak of the viral load and development of histopathological changes compared to a lower dose, but no difference in the severity of the disease.
Conclusions:
The experiment demonstrated that PRV can be purified from blood cells, and that PRV is the etiological agent of HSMI in Atlantic salmon.
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Brudal, Espen; Milton, Debra L; myrtennäs, Kerstin; Roos, Norbert; Griffiths, Gareth Wyn & Winther-Larsen, Hanne C.
(2014).
A degenerative Type IV pilus like system is functional and required for virulence in the fish pathogen Francisella noatunensis subsp. noatunensis.
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Vik, Åshild; Anonsen, Jan Haug; Aas, Finn Erik; Hegge, Finn Terje; Roos, Norbert & Koomey, Michael
[Show all 7 contributors for this article]
(2014).
Type IV pilus assembly proficiency and dynamics influence pilin subunit phospho-form marcro- and microheterogeneity in Neisseria gonorrhoeae.
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Lystad, Alf Håkon; Sporstol, Marita; Foroughi, Masoud; Roos, Norbert; Berg, Trond & Eskild, Winnie
(2009).
Regulation of VEGF expression by vitamin D i hepatic stellate cells - possible attenuation by the nuclear receptor coregulator NCY-G1.
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Lystad, Alf Håkon; Sporstol, Marita; Foroughi, Masoud; Roos, Norbert; Berg, Trond & Eskild, Winnie
(2009).
Regulation of VEGF expression by vitamin D in hepatic stellate cells - possible attenuation by the nuclear receptor coregulator NCU-G1.
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Farkas, Julia; Christian, P.; Hylland, Ketil ; Ellesat, Kathrin; Roos, Norbert & Urrea, J.
[Show all 9 contributors for this article]
(2009).
Effects of Silver and Gold nanoparticles on rainbow trout (Oncorhynchus mykiss) hepatocytes.
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Salomonsson, Emelie; Koomey, Michael; Roos, Norbert; Forsberg, Åke & Winther-Larsen, Hanne C
(2007).
Exploring the role of virulence-associated pilin proteins from Francisella tularensis using heterologous expression in Neisseria.
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Salomonsson, Emelie; Koomey, Michael; Roos, Norbert; Forsberg, Åke & Winther-Larsen, Hanne C
(2007).
Knowledge about the bioterrorism class A agent Francisella tularensis by utilizing Neisseria gonorrhoeae.
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Kåsi, Cecilie; Sporstol, Marita; Roos, Norbert; Berg, Trond & Eskild, Winnie
(2007).
NUCLEAR RECEPTORS IN HEPATIC STELLATE CELL ACTIVATION.
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Winther-Larsen, Hanne C; Heiniger, Ryan W; Roos, Norbert; Egge-Jacobsen, Wolfgang; van Putten, JPM & Koomey, Michael
[Show all 7 contributors for this article]
(2006).
Dynamics of Type IV pili Biogenesis in Pseudomonas aeruginosa.
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Winther-Larsen, Hanne C; Heiniger, Ryan; Roos, Norbert; van Putten, JPM; Koomey, Michael & Wolfgang, Matthew
(2006).
Dynamics of Type IV pilus biogenesis in Pseudomonas aeruginosa.
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Løvold, Cecilia; Aas, Finn Erik; Winther-Larsen, Hanne C; Egge-Jacobsen, Wolfgang; Hegge, Finn Terje & Roos, Norbert
[Show all 8 contributors for this article]
(2005).
Mutant analysis of dca: a gene encoding a putative transferase that mediates phosphoethanolamine and phosphocholine modifications of the Type IV pili in Neisseria gonorrhoeae.
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Winther-Larsen, Hanne C; Løvold, Cecilia; Wolfgang, Matthew; van Putten, JPM; Roos, Norbert & Aas, Finn Erik
[Show all 10 contributors for this article]
(2005).
Pseudomonas aeruginosa PAK Type IV pili expression in Neisseria gonorrhoeae complements Tfp associated functions.
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Aas, Finn Erik; Løvold, Cecilia; Winther-Larsen, Hanne C; Jacobsen, Wolfgang Mathias; Roos, Norbert & Koomey, John Michael
(2004).
Characterization of dca, a gene involved in posttranslational modification of Neisseria gonorrhoeae Type IV Pili with phosphoethanolamine and phosphocholine.
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Winther-Larsen, Hanne C; Løvold, Cecilia; Aas, Finn Erik; Roos, Norbert & Koomey, John Michael
(2004).
Complementation of both transformation competence and human cell adherence by hetrologous expression of the Pseudomonas aeruginosa Type IV pilin sunbunit in Neisseria gonorrhoea.
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Winther-Larsen, Hanne C; Løvold, Cecilia; Aas, Finn Erik; Roos, Norbert & Koomey, John Michael
(2004).
Complementation of both transformation competence and human cell adherence by hetrologous expression of the Pseudomonas aeruginosa Type IV pilin sunbunit in Neisseria gonorrhoea.
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Winther-Larsen, Hanne C; Løvold, Cecilia; Aas, Finn Erik; Roos, Norbert & Koomey, John Michael
(2004).
Complementation of both transformation competence and human cell adherence by hetrologous expression of the Pseudomonas aeruginosa Type IV pilin sunbunit in Neisseria gonorrhoea.
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Oksvold, Morten Pedersen; Skarpen, Ellen; Roos, Norbert & Huitfeldt, Henrik
(1999).
Immunocytochemical localization of ligand-activated phosphorylated EGFR in endosomes.
Proceedings of the American Association of Cancer Research.
ISSN 0197-016X.
40.
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Senoo, Haruki; Imamura, Kazuyuki; Wake, Kenjiro; Wold, Heidi L.; Moshaug, Jan Øivind & Kojima, Naosuke
[Show all 14 contributors for this article]
(1998).
Vitamin A-storing system in mammals and birds in the arctic area - a study in the Svalbard archipelago.
Show summary
Arctic animals (polar bears, polar foxes, ringed seals etc) store large amounts of vitamin A in hepatic stellate cells. These animals do not show hypervitaminosis A.
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Roos, Norbert; Cyrklaff, Marek; Cudmore, Sally; Krijnse-Locker, Jacomine; Blasco, Rafael & Griffiths, Gareth Wyn
(1995).
Cryo EM immunocytochemical analysis of the two infectious forms of vaccinia virus.
European Journal of Cell Biology.
ISSN 0171-9335.
p. 108–109.
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Roos, Norbert
(1992).
Book review.
Ultramicroscopy.
ISSN 0304-3991.
40,
p. 191–194.
