Fernanda Cristina Petersen

• Filho, Antonio Pedro Ricomini; Khan, Rabia; Åmdal, Heidi Aarø & Petersen, Fernanda Cristina (2019). Conserved Pheromone Production, Response and Degradation by Streptococcus mutans. Frontiers in Microbiology.  ISSN 1664-302X. Show summary

  Streptococcus mutans, a bacterium with high cariogenic potential, coordinates competence for natural transformation and bacteriocin production via the XIP and CSP pheromones. CSP is effective in inducing bacteriocin responses but not competence in chemically defined media (CDM). This is in contrast to XIP, which is a strong inducer of competence in CDM but can also stimulate bacteriocin genes as a late response. Interconnections between the pathways activated by the two pheromones have been characterized in certain detail in S. mutans UA159, but it is mostly unknown whether such findings are representative for the species. In this study, we used bioassays based on luciferase reporters for the bacteriocin gene cipB and the alternative sigma factor sigX to investigate various S. mutans isolates for production and response to CSP and XIP pheromones in CDM. Similar to S. mutans UA159, endogenous CSP was undetectable in the culture supernatants of all tested strains. During optimization of the bioassay using the cipB reporter, we discovered that the activity of exogenous CSP used as a standard was reduced over time during S. mutans growth. Using a FRET-CSP reporter peptide, we found that S. mutans UA159 was able to degrade CSP, and that such activity was not significantly different in isogenic mutants with deletion of the protease gene htrA or the competence genes sigX, oppD, and comR. CSP cleavage was also detected in all the wild type strains, indicating that this is a conserved feature in S. mutans. For the XIP pheromone, endogenous production was observed in the supernatants of all 34 tested strains at peak concentrations in culture supernatants that varied between 200 and 26000 nM. Transformation in the presence of exogenous XIP was detected in all but one of the isolates. The efficiency of transformation varied, however, among the different strains, and for those with the highest transformation rates, endogenous XIP peak concentrations in the supernatants were above 2000 nM XIP. We conclude that XIP production and inducing effect on transformation, as well as the ability to degrade CSP, are conserved functions among different S. mutans isolates. Understanding the functionality and conservation of pheromone systems in S. mutans may lead to novel strategies to prevent or treat unbalances in oral microbiomes that may favor diseases.

• Geissler, Sebastian; Gomez-Florit, Manuel; Wiedmer, David; Barrantes Bautista, Alejandro; Petersen, Fernanda Cristina & Tiainen, Hanna (2019). In vitro performance of bioinspired phenolic nanocoatings for endosseous implant applications. ACS biomaterials science & engineering.  ISSN 2373-9878. . doi: 10.1021/acsbiomaterials.9b00566
• Junges, Roger; Maienschein-Cline, Mark; Morrison, Donald A. & Petersen, Fernanda Cristina (2019). Complete Genome Sequence of Streptococcus pneumoniae Serotype 19F Strain EF3030. Microbiology Resource Announcements (MRA).  ISSN 2169-8287.  8(19), s 1- 3 . doi: 10.1128/MRA.00198-19
• Junges, Roger; Salvadori, Gabriela; Chen, Tsute; Morrison, Donald A. & Petersen, Fernanda Cristina (2019). Hidden Gems in the Transcriptome Maps of Competent Streptococci. Frontiers in Molecular Biosciences.  ISSN 2296-889X.  5, s 1- 7 . doi: 10.3389/fmolb.2018.00116
• Junges, Roger; Sturød, Kjersti; Salvadori, Gabriela; Åmdal, Heidi Aarø; Chen, Tsute & Petersen, Fernanda Cristina (2019). Characterization of a Signaling System in Streptococcus mitis That Mediates Interspecies Communication with Streptococcus pneumoniae. Applied and Environmental Microbiology.  ISSN 0099-2240.  85(2) . doi: 10.1128/AEM.02297-18
• Khan, Rabia; Petersen, Fernanda Cristina & Shekhar, Sudhanshu (2019). Commensal bacteria: An emerging player in defense against respiratory pathogens. Frontiers in Immunology.  ISSN 1664-3224.  10:1203(MAY), s 1- 9 . doi: 10.3389/fimmu.2019.01203
• Salvadori, Gabriela; Junges, Roger; Morrison, Donald A. & Petersen, Fernanda Cristina (2019). Competence in Streptococcus pneumoniae and Close Commensal Relatives: Mechanisms and Implications. Frontiers in Cellular and Infection Microbiology.  ISSN 2235-2988.  9:94, s 1- 8 . doi: 10.3389/fcimb.2019.00094
• Salvadori, Gabriela; Junges, Roger; Morrison, Donald A & Petersen, Fernanda Cristina (2019). Competence in Streptococcus pneumoniae and Close Commensal Relatives: Mechanisms and Implications. Frontiers in Cellular and Infection Microbiology.  ISSN 2235-2988.
• Shekhar, Sudhanshu; Khan, Rabia; Khan, Ata Ul Razzaq & Petersen, Fernanda Cristina (2019). Mouse IgG2a Antibodies Specific for the Commensal Streptococcus mitis Show Stronger Cross-Reactivity with Streptococcus pneumoniae than IgG1 Antibodies. Journal of Immunology Research.  ISSN 2314-8861.  2019 . doi: 10.1155/2019/7906724
• Shekhar, Sudhanshu; Khan, Rabia; Schenck, Karl & Petersen, Fernanda Cristina (2019). Intranasal Immunization with the Commensal Streptococcus mitis Confers Protective Immunity against Pneumococcal Lung Infection. Applied and Environmental Microbiology.  ISSN 0099-2240.  85(6) . doi: 10.1128/AEM.02235-18
• Shekhar, Sudhanshu; Petersen, Fernanda Cristina & Yang, Xi (2019). Understanding and exploiting host-commensal interactions to combat pathogens. Frontiers in Immunology.  ISSN 1664-3224. . doi: 10.3389/fimmu.2019.02645
• Sturød, Kjersti; Dhariwal, Achal; Dahle, Ulf R; Vestrheim, Didrik Frimann & Petersen, Fernanda Cristina (2019). Impact of narrow spectrum Penicillin V on the oral and fecal resistome in a young child treated for otitis media. Journal of Global Antimicrobial Resistance.  ISSN 2213-7165.
• Lauren A., Cowley; Petersen, Fernanda Cristina; Junges, Roger; Jimenez, M; Morrison, Donald A. & Hanage, WP (2018). Evolution via recombination: Cell-to-cell contact facilitates larger recombination events in Streptococcus pneumoniae. PLoS Genetics.  ISSN 1553-7390.  14(6) . doi: 10.1371/journal.pgen.1007410
• Reglinski, Mark; Ercoli, Giuseppe; Plumptre, Charlie; Kay, Emily; Petersen, Fernanda Cristina; Paton, James C; Wren, Brendan W. & Brown, Jeremy (2018). A recombinant conjugated pneumococcal vaccine that protects against murine infections with a similar efficacy to Prevnar-13. npj Vaccines.  ISSN 2059-0105.  3, s 1- 11 . doi: 10.1038/s41541-018-0090-4
• Salvadori, Gabriela; Junges, Roger; Åmdal, Heidi Aarø; Chen, T.; Morrison, D.A. & Petersen, Fernanda Cristina (2018). High-resolution profiles of the Streptococcus mitis CSP signaling pathway reveal core and strain-specific regulated genes. BMC Genomics.  ISSN 1471-2164.  19(1) . doi: 10.1186/s12864-018-4802-y
• Shekhar, Sudhanshu; Khan, Rabia; Ferreira, Daniela M.; Mitsi, Elena; German, Esther; Rørvik, Gro Herredsvela; Berild, Dag; Schenck, Karl; Kwon, Keehwan & Petersen, Fernanda Cristina (2018). Antibodies reactive to commensal Streptococcus mitis show cross-reactivity with virulent Streptococcus pneumoniae serotypes. Frontiers in Immunology.  ISSN 1664-3224.  9:747, s 1- 10 . doi: 10.3389/fimmu.2018.00747 Full text in Research Archive. Show summary

  Current vaccines against Streptococcus pneumoniae, a bacterial species that afflicts people by causing a wide spectrum of diseases, do not protect against all pneumococcal serotypes. Thus, alternative vaccines to fight pneumococcal infections that target common proteins are under investigation. One promising strategy is to take advantage of immune cross-reactivity between commensal and pathogenic microbes for cross-protection. In this study, we examined the antibody-mediated cross-reactivity between S. pneumoniae and Streptococcus mitis, a commensal species closely related to S. pneumoniae. Western blot analysis showed that rabbit antisera raised against S. mitis reacted with multiple proteins of virulent S. pneumoniae strains (6B, TIGR4, and D39). Rabbit anti-S. pneumoniae IgG antibodies also showed binding to S. mitis antigens. Incubation of rabbit antisera raised against S. mitis with heterologous or homologous bacterial lysates resulted in marked inhibition of the developments of bands in the Western blots. Furthermore, plasma IgG antibodies from adult human volunteers intranasally inoculated with S. pneumoniae 6B revealed enhanced S. mitis-specific IgG titers compared with the pre-inoculation samples. Using an on-chip protein microarray representing a number of selected membrane and extracellular S. pneumoniae proteins, we identified choline-binding protein D (CbpD), cell division protein (FtsH), and manganese ABC transporter or manganese-binding adhesion lipoprotein (PsaA) as common targets of the rabbit IgG antibodies raised against S. mitis or S. pneumoniae. Cumulatively, these findings provide evidence on the antibody-mediated cross-reactivity of proteins from S. mitis and S. pneumoniae, which may have implications for development of effective and wide-range pneumococcal vaccines.

• Shekhar, Sudhanshu; Schenck, Karl & Petersen, Fernanda Cristina (2018). Exploring Host–Commensal Interactions in the Respiratory Tract. Frontiers in Immunology.  ISSN 1664-3224.  8, s 1- 7 . doi: 10.3389/fimmu.2017.01971 Full text in Research Archive. Show summary

  Commensal microbes are currently in the limelight in biomedical research because they play an important role in health and disease. Humans harbor an enormous diversity of commensals in various parts of the body, including the gastrointestinal and respiratory tracts. Advancement in metagenomic and other omic approaches, and development of suitable animal models have provided an unprecedented appreciation into the diversity of commensals, and the intricacies of their intimate communication with the host immune system. Most studies have focused on the host–commensal interaction in the gut, while less is known on this relationship in other sites of the body, such as the respiratory tract. In this article, we review emerging data from human and animal studies on the host responses to respiratory commensals, immune cross-reactivity between commensals and pathogens, and use of commensals as a vaccine delivery system. A better understanding of the delicate interplay between commensals and host may aid in efforts to develop effective vaccines and therapeutics.

• Sturød, Kjersti; Salvadori, Gabriela; Junges, Roger & Petersen, Fernanda Cristina (2018). Antibiotics alter the window of competence for natural transformation in streptococci. Molecular Oral Microbiology.  ISSN 2041-1006.  33(5), s 378- 387 . doi: 10.1111/omi.12240
• Wiedmer, David; Cui, Chen; Weber, Florian; Petersen, Fernanda Cristina & Tiainen, Hanna (2018). Antibacterial Surface Coating for Bone Scaffolds Based on the Dark Catalytic Effect of Titanium Dioxide. ACS Applied Materials & Interfaces.  ISSN 1944-8244.  10(42), s 35784- 35793 . doi: 10.1021/acsami.8b12623
• Engen, Stian André; Schreurs, Olaf Joseph Franciscus; Petersen, Fernanda Cristina; Blix, Inger Johanne S.; Bækkevold, Espen Sønderaal & Schenck, Karl (2017). The Regulatory Role of the Oral Commensal Streptococcus mitis on Human Monocytes. Scandinavian Journal of Immunology.  ISSN 0300-9475.  87(2), s 80- 87 . doi: 10.1111/sji.12636
• Junges, Roger; Khan, Rabia; Tovpeko, Yanina; Åmdal, Heidi Aarø; Petersen, Fernanda Cristina & Morrison, Donald (2017). Markerless genome editing in competent streptococci. Methods in molecular biology.  ISSN 1064-3745.  1537, s 233- 247 . doi: 10.1007/978-1-4939-6685-1_14 Full text in Research Archive.
• Junges, Roger; Salvadori, Gabriela; Shekhar, Sudhanshu; Åmdal, Heidi Aarø; Periselneris, Jimstan; Chen, Tsute; Brown, Jeremy S. & Petersen, Fernanda Cristina (2017). A quorum-sensing system that regulates Streptococcus pneumoniae biofilm formation and surface polysaccharide production. mSphere.  ISSN 2379-5042.  2(5), s 1- 18 . doi: 10.1128/mSphere.00324-17 Full text in Research Archive.
• Khan, Rabia; Junges, Roger; Åmdal, Heidi Aarø; Chen, Tsute; Morrison, Donald A & Petersen, Fernanda Cristina (2017). A positive feedback loop mediated by Sigma X enhances expression of the streptococcal regulator ComR. Scientific Reports.  ISSN 2045-2322.  7(1) . doi: 10.1038/s41598-017-04768-5 Full text in Research Archive.
• Rukke, Håkon Valen; Scheie, Anne Aamdal & Petersen, Fernanda Cristina (2017). Oral mikroflora - et reservoar av antibiotikaresistensgener. Aktuell Nordisk odontologi.  ISSN 1902-3545.  s 43- 59 . doi: 10.18261 Show summary

  Et av de store fremskrittene innen medisinen i det forrige århundre var oppdagelsen av antibiotika. Kort tid etter introduksjonen av ulike antibiotika oppdaget man at bakteriene kunne bli resistente. Resistens mot antibiotika er en global trussel og utfordring. Bare innen Den europeiske union, Island og Norge var det estimert at infeksjoner med antibiotikaresistente bakterier kostet 25.000 mennesker livet i 2007. Bakterier kan bli resistente enten ved spontane mutasjoner eller ved opptak av DNA fra miljøet, en prosess kjent som horisontal genoverføring. Gener som gir opphav til resistens, finnes i miljøet rundt oss og i den humane normalflora, inkludert den orale mikrobiota. Normalfloraen utgjør et reservoar av resistensgener, som kan overføres til mer patogene bakterier. Bruk av antibiotika selekterer for resistente bakterier og kan stimulere til horisontal genoverføring. Økningen av resistente bakterier krever en bevisst holdning til forskrivelse og bruk av antibiotika. Bruk bør forbeholdes og være basert på evidensbasert kunnskap, der det er til nytte for pasienten.

• Salvadori, Gabriela; Junges, Roger; Khan, Rabia; Åmdal, Heidi Aarø; Morrison, Donald A. & Petersen, Fernanda Cristina (2017). Natural transformation of oral streptococci by use of synthetic pheromones. Methods in molecular biology.  ISSN 1064-3745.  s 219- 232 . doi: 10.1007/978-1-4939-6685-1_13 Full text in Research Archive.
• Wiedmer, David; Petersen, Fernanda Cristina; Lönn-Stensrud, Jessica & Tiainen, Hanna (2017). Antibacterial effect of hydrogen peroxide - titanium dioxide suspensions in the decontamination of rough titanium surfaces. Biofouling (Print).  ISSN 0892-7014.  33(6), s 451- 459 . doi: 10.1080/08927014.2017.1322585 Full text in Research Archive.
• Wilson, Robert; Cohen, Jonathan M.; Reglinski, Mark; Jose, Ricardo J.; Chan, Win Yan; Marshall, Helina-Elaine; de Vogel, Corné; Gordon, Stephen V.; Goldblatt, David; Petersen, Fernanda Cristina; Baxendale, Helen & Brown, Jeremy S. (2017). Naturally acquired human immunity to pneumococcus is dependent on antibody to protein antigens. PLoS Pathogens.  ISSN 1553-7366.  13:e1006137(1) . doi: 10.1371/journal.ppat.1006137 Full text in Research Archive.
• Khan, Rabia; Rukke, Håkon Valen; Høvik, Hedda; Åmdal, Heidi Aarø; Chen, T.; Morrison, Donald A. & Petersen, Fernanda Cristina (2016). Comprehensive Transcriptome Profiles of Streptococcus mutans UA159 Map Core Streptococcal Competence Genes. mSystems.  ISSN 2379-5077.  1(2) . doi: 10.1128/mSystems.00038-15 Full text in Research Archive. Show summary

  In Streptococcus mutans, an oral colonizer associated with dental caries, development of competence for natural genetic transformation is triggered by either of two types of peptide pheromones, competence-stimulating peptides (CSPs) (18 amino acids [aa]) or SigX-inducing peptides (XIPs) (7 aa). Competence induced by CSP is a late response to the pheromone that requires the response regulator ComE and the XIP-encoding gene comS. XIP binds to ComR to allow expression of the alternative sigma factor SigX and the effector genes it controls. While these regulatory links are established, the precise set of effectors controlled by each regulator is poorly defined. To improve the definition of all three regulons, we used a high-resolution tiling array to map global changes in gene expression in the early and late phases of the CSP response. The early phase of the CSP response was limited to increased gene expression at four loci associated with bacteriocin production and immunity. In the late phase, upregulated regions expanded to a total of 29 loci, including comS and genes required for DNA uptake and recombination. The results indicate that the entire late response to CSP depends on the expression of comS and that the immediate transcriptional response to CSP, mediated by ComE, is restricted to just four bacteriocin-related loci. Comparison of the new data with published transcriptome data permitted the identification of all of the operons in each regulon: 4 for ComE, 2 for ComR, and 21 for SigX. Finally, a core set of 27 panstreptococcal competence genes was identified within the SigX regulon by comparison of transcriptome data from diverse streptococcal species.

• Rukke, Håkon Valen; Engen, Stian André; Schenck, Karl & Petersen, Fernanda Cristina (2016). Capsule expression in Streptococcus mitis modulates interaction with oral keratinocytes and alters susceptibility to human antimicrobial peptides. Molecular Oral Microbiology.  ISSN 2041-1006.  31(4), s 302- 313 . doi: 10.1111/omi.12123 Show summary

  Streptococcus mitis is a colonizer of the oral cavity and the nasopharynx, and is closely related to Streptococcus pneumoniae. Both species occur in encapsulated and unencapsulated forms, but in S. mitis the role of the capsule in host interactions is mostly unknown. Therefore, the aim of this study was to examine how capsule expression in S. mitis can modulate interactions with the host with relevance for colonization. The S. mitis type strain, as well as two mutants of the type strain, an isogenic capsule deletion mutant, and a capsule switch mutant expressing the serotype 4 capsule of S. pneumoniae TIGR4, were used. Wild-type and capsule deletion strains of S. pneumoniae TIGR4 were included for comparison. We found that capsule production in S. mitis reduced adhesion to oral and lung epithelial cells. Further, exposure of oral epithelial cells to encapsulated S. mitis resulted in higher interleukin-6 and CXCL-8 transcription levels relative to the unencapsulated mutant. Capsule expression in S. mitis increased the sensitivity to human neutrophil peptide 1-3 but reduced the sensitivity to human β-defensin-3 and cathelicidin. This was in contrast with S. pneumoniae in which capsule expression has been generally associated with increased sensitivity to human antimicrobial peptides (AMPs). Collectively, these findings indicate that capsule expression in S. mitis is important in modulating interactions with epithelial cells, and is associated with increased or reduced susceptibility to AMPs depending on the nature of the AMP.

• Salvadori, Gabriela; Junges, Roger; Morrison, Donald A. & Petersen, Fernanda Cristina (2016). Overcoming the barrier of low efficiency during Genetic transformation of Streptococcus mitis. Frontiers in Microbiology.  ISSN 1664-302X.  7 . doi: 10.3389/fmicb.2016.01009 Full text in Research Archive.
• Salvadori, Gabriela; Junges, Roger; Morrison, Donald A. & Petersen, Fernanda Cristina (2016). Overcoming the barrier of low efficiency during natural transformation of Streptococcus mitis. Frontiers in Microbiology.  ISSN 1664-302X.
• Morrison, D.A.; Khan, Rabia; Junges, Roger; Åmdal, Heidi Aarø & Petersen, Fernanda Cristina (2015). Genome editing by natural genetic transformation in Streptococcus mutans. Journal of Microbiological Methods.  ISSN 0167-7012.  119, s 134- 141 . doi: 10.1016/j.mimet.2015.09.023

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• Fejerskov, Ole; Nyvad, Bente; Kidd, Edwina; Scheie, Anne Aamdal; Rukke, Håkon Valen & Petersen, Fernanda Cristina (2015). Are antimicrobials necessary in caries prophylaxis?. Wiley Blackwell.  ISBN 9781118935828.  12 s.

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• Dhariwal, Achal & Petersen, Fernanda Cristina (2019). Visual exploration and network-based analysis of resistome data.
• Junges, Roger; Salvadori, Gabriela; Chen, Tsute & Petersen, Fernanda Cristina (2019). Identification of a ComRS-like regulator system in the mitis group of streptococci.
• Pagotto, LL; Junges, Roger; Salvadori, Gabriela; Petersen, Fernanda Cristina & Ricomoni Filho, Antonio Pedro (2019). Inhibition of Streptococcus mutans competence by chlorhexidine gluconate.
• Petersen, Fernanda Cristina (2019). Aging in the twilight of antibiotics.
• Petersen, Fernanda Cristina (2019). Mikrobiom og antibiotikaresistens.
• Petersen, Fernanda Cristina (2019). Resistance after long term antibiotic treatment.
• Petersen, Fernanda Cristina & Kolstad, Hilde Zwaig (ed.) (2019). - Har aldri sett så mye snø!.
• Petersen, Fernanda Cristina & Kolstad, Hilde Zwaig (red.) (2019). Gratulerer til Roger Junges som i dag mottok Den norske tannlegeforening sin pris for undervisning og forskning!.
• Petersen, Fernanda Cristina & størseth, inger (ed.) (2019). Resistance after long-term antibiotic treatment.
• Petersen, Fernanda Cristina & størseth, inger (red.) (2019). Utvekslingsopphold i Brasil.
• Petersen, Fernanda Cristina; Torheim, Norunn Kristin & Vistnes, Torunn (red.) (2019). Lysvandring i Botanisk hage: Kommunikasjon mellom bakterier.
• Petersen, Fernanda Cristina & Torwick, Anna (ed.) (2019). Born in the twilight of antibiotics.
• Petersen, Fernanda Cristina & Torwick, Anna (ed.) (2019). Enhancing world-class research and education in biofilm and antibiotic resistance by strengthening cooperation between Norway-Brazil-USA.
• Salvadori, Gabriela & Petersen, Fernanda Cristina (2019). Functional Metagenomics: A Tool to Study Antimicrobial Resistance in Saliva.
• Dhariwal, Achal & Petersen, Fernanda Cristina (2018). Network-based analysis of Resistome data.
• Junges, Roger & Petersen, Fernanda Cristina (2018). Eavesdropping on bacterial conversations: what are they doing and do they understand each other?.
• Junges, Roger & Petersen, Fernanda Cristina (2018). Interspecies cell-to-cell communication in the mitis group of streptococci.
• Junges, Roger & Petersen, Fernanda Cristina (2018). Rgg/SHP cross-communication in the mitis group of streptococci.
• Junges, Roger; Petersen, Fernanda Cristina; Egija, Zaura; Lemos, José A. & Merritt, Justin (2018). Environmental and antibiotic stress on oral bacteria: a target for new therapies.
• Junges, Roger; Sturød, Kjersti; Salvadori, Gabriela; Åmdal, Heidi Aarø; Chen, Tsute & Petersen, Fernanda Cristina (2018). Interspecies activation of a virulent pathway by an oral commensal.
• Morrison, Donald A.; Jimenez, Med; Cowley, Lauren A.; Junges, Roger; Petersen, Fernanda Cristina & Hanage, William P. (2018). Genomic signature of natural genetic transformation shared by S. pneumoniae and S. pyogenes.
• Petersen, Fernanda Cristina (2018). Antibiotic stress and bacterial cell-to-cell communication.
• Petersen, Fernanda Cristina (2018). Born in the Twilight of Antibiotics.
• Petersen, Fernanda Cristina (2018, 01. april). Fikk Thon-penger. [Fagblad].  Den Norske Tannlegeforenings Tidende.
• Petersen, Fernanda Cristina (2018, 08. februar). Life Science: Antibiotikaresistens.  Aftenposten.
• Petersen, Fernanda Cristina (2018). Massive Open Online Courses and antimicrobial resistance.
• Petersen, Fernanda Cristina (2018). Projects by the Oslo Group: an overview.
• Petersen, Fernanda Cristina (2018). RESISPART- Inaugural Remarks.
• Petersen, Fernanda Cristina (2018). Streptococcal life.
• Petersen, Fernanda Cristina (2018). The INDNOR project.
• Petersen, Fernanda Cristina (2018). The Oslo group: expertise and tools.
• Salvadori, Gabriela; Junges, Roger; Åmdal, Heidi Aarø; Chen, Tsute; Morrison, Donald A & Petersen, Fernanda Cristina (2018). Insights into regulatory pathways of competence development in Streptococcus mitis type strain and SK321.
• Salvadori, Gabriela; Junges, Roger; Åmdal, Heidi Aarø; Chen, Tsute; Morrison, Donald A & Petersen, Fernanda Cristina (2018). Molecular Characterization of Genetic Competence in Streptococcus mitis.
• Sturød, Kjersti; Salvadori, Gabriela; Junges, Roger & Petersen, Fernanda Cristina (2018). Antibiotic Induced Streptococcal Competence Not Always Correlate with Transformability.
• Tiainen, Hanna; Wiedmer, David & Petersen, Fernanda Cristina (2018). Biofilm formation and planktonic growth of S. epidermidis in the presence of phenolic compounds tannic acid and pyrogallol.
• Wiedmer, David; Cui, Chen; Petersen, Fernanda Cristina & Tiainen, Hanna (2018). Antibacterial sol-gel coating for bone scaffolds based on the dark catalytic effect of titanium dioxide.
• Cowley, Lauren A.; Petersen, Fernanda Cristina; Junges, Roger; Hanage, William P & Morrison, Donald A. (2017). Co-culture of S. pneumoniae strains fosters large recombination events.
• Cowley, Lauren A.; Petersen, Fernanda Cristina; Junges, Roger; Hanage, William P & Morrison, Donald A. (2017). Large recombination events readily occurring in biofilm cultures of Streptococcus pneumoniae.
• Engen, Stian; Schreurs, Olaf Joseph Franciscus; Petersen, Fernanda Cristina; Blix, Inger Johanne S.; Bækkevold, Espen Sønderaal & Schenck, Karl (2017). Regulation of human monocytes by the oral commensal Streptococcus mitis: a role for PGE2?.
• Gomez-Florit, Manuel; Geissler, Sebastian; Wiedmer, David; Petersen, Fernanda Cristina & Tiainen, Hanna (2017). Multifunctional polyphenol nanocoatings for improved tissue integration of dental implants.
• Junges, Roger; Salvadori, Gabriela; Chen, Tsute; Åmdal, Heidi A.; Jimstan N., Periselneris; Jeremy S., Brown & Petersen, Fernanda Cristina (2017). A bacterial pheromone system regulates biofilm formation and colonization..
• Junges, Roger; Salvadori, Gabriela; Sudhanshu, Shekhar; Åmdal, Heidi A.; Jimstan N., Periselneris; Chen, Tsute; Jeremy S., Brown & Petersen, Fernanda Cristina (2017). An Rgg/SHP quorum sensing system reduces virulence and fitness in Streptococcus pneumoniae.
• Rørvik, Gro Herredsvela; Schreurs, Olaf Joseph Franciscus; Engen, Stian; Blix, Inger Johanne S.; Petersen, Fernanda Cristina & Schenck, Karl (2017). Antibody reactivity to the oral commensal Streptococcus mitis in serum and saliva.
• Salvadori, Gabriela; Junges, Roger & Petersen, Fernanda Cristina (2017). A Competence-Induced Bacteriocin Reduces Growth of Oral Pathogenic Bacteria.
• Salvadori, Gabriela; Junges, Roger; Chen, Tsute & Petersen, Fernanda Cristina (2017). A Competence-Induced Bacteriocin Reduces Growth of Oral Pathogenic Bacteria..
• Salvadori, Gabriela; Junges, Roger; Morrison, Donald A. & Petersen, Fernanda Cristina (2017). High efficiency genetic transformation in encapsulated pneumococcus.
• Shekhar, Sudhanshu; Khan, Rabia; Ferreira, Daniela; Schenck, Karl; Kwon, Keehwan & Petersen, Fernanda Cristina (2017). Streptococcus mitis-specific antibodies show cross-reactivity with a range of virulent Streptococcus pneumoniae serotypes.
• Shekhar, Sudhanshu; Khan, Rabia; Ferreira, Daniela; Schenck, Karl; Kwon, Keehwan & Petersen, Fernanda Cristina (2017). Streptococcus mitis-specific antibodies show cross-reactivity with a range of virulent Streptococcus pneumoniae serotypes.
• Junges, Roger; Khan, Rabia; Åmdal, Heidi A.; Morrison, Donald A. & Petersen, Fernanda Cristina (2016). Markerless Genome Editing in Oral Streptococci.
• Junges, Roger; Salvadori, Gabriela; Morrison, Donald A. & Petersen, Fernanda Cristina (2016). High efficiency genetic transformation in Streptococcus Mitis.
• Junges, Roger; Salvadori, Gabriela; Åmdal, Heidi A.; Morrison, Donald A.; Chen, Tsute & Petersen, Fernanda Cristina (2016). Global response of Streptococcus mitis to the competence-stimulating peptide.
• Khan, Rabia; Shekhar, Sudhanshu & Petersen, Fernanda Cristina (2016). Identification of common surface exposed proteins between S. mitis and S. pneumoniae by cell surface shaving proteomics.
• Salvadori, Gabriela; Junges, Roger; Chen, Tsute; Morrison, Donald A. & Petersen, Fernanda Cristina (2016). High-resolution profiles of the CSP signaling pathway in Streptococcus mitis SK321 and NCTC12261T..
• Salvadori, Gabriela; Junges, Roger; Åmdal, Heidi A.; Chen, Tsute & Petersen, Fernanda Cristina (2016). Transcriptome response of Streptococcus mitis to the competence pheromone (Hatton Award representation).
• Wiedmer, David; Tiainen, Hanna; Lönn-Stensrud, Jessica; Petersen, Fernanda Cristina & Haugen, Håvard Jostein (2016). TiO2-H2O2 as decontamination agent - an in vitro study.
• Wiedmer, David; Tiainen, Hanna; Petersen, Fernanda Cristina & Haugen, Håvard Jostein (2016). H2O2-TiO2 as potential treatment for peri-implantitis – an in vitro study.
• Engen, Stian André; Rukke, Håkon Valen; Becattini, Simone; Jarrossay, David; Blix, Inger Johanne S.; Petersen, Fernanda Cristina; Sallusto, Federica & Schenck, Karl (2015). The oral commensal Streptococcus mitis shows a mixed memory Th cell signature that is similar to and cross-reactive with Streptococcus pneumoniae..
• Junges, Roger; Khan, Rabia; Åmdal, Heidi Aarø; Morrison, Donald A. & Petersen, Fernanda Cristina (2015). A new link between two Streptococcus mutans pheromones.
• Junges, Roger; Khan, Rabia; Åmdal, Heidi Aarø; Morrison, Donald A. & Petersen, Fernanda Cristina (2015). Transcriptome response of Streptoccocus mutans to the sigX-inducing peptide (XIP).
• Junges, Roger; Åmdal, Heidi Aarø; Chen, Tsute & Petersen, Fernanda Cristina (2015). A New Pheromone in Streptococcus mitis Enhances Biofilm Formation.
• Junges, Roger; Åmdal, Heidi Aarø; Chen, Tsute & Petersen, Fernanda Cristina (2015). Characterization of an Rgg/SHP system in Streptococcus mitis that allows communication with Streptococcus pneumoniae.
• Marshall, Helina-Elaine; Petersen, Fernanda Cristina & Brown, Jeremy (2015). Differential complement sensitivity of Streptococcus pneumoniae and Streptococcus mitis.
• Petersen, Fernanda Cristina; Khan, Rabia; Junges, Roger; Åmdal, Heidi Aarø; Chen, Tsute & Morrison, Donald A. (2015). A new link between the Streptococcus mutans XIP and CSP pheromone pathways revealed by directional RNA-sequencing.
• Salvadori, Gabriela; Junges, Roger; Åmdal, Heidi Aarø; Chen, Tsute & Petersen, Fernanda Cristina (2015). Identification of Streptococcus mitis competence pheromone responsive genes by transcriptome analysis.
• Salvadori, Gabriela; Junges, Roger; Åmdal, Heidi Aarø; Chen, Tsute & Petersen, Fernanda Cristina (2015). Transcriptome response of Streptococcus mitis to the competence pheromone.
• Silva, Gabriela Salvadori; Junges, Roger; Åmdal, Heidi Aarø; Chen, Tsute & Petersen, Fernanda Cristina (2015). Streptococcus mitis response to the competence pheromone.
• Silva, Gabriela Salvadori; Junges, Roger; Åmdal, Heidi Aarø; Chen, Tsute & Petersen, Fernanda Cristina (2015). Transcriptome analysis of Streptococcus mitis response to the competence pheromone.

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