Malmö University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Responses to External Cues in Oral Bacteria
Malmö University, Faculty of Odontology (OD). Malmö University, Biofilms Research Center for Biointerfaces. (Department of Oral Biology and Pathology)ORCID iD: 0000-0001-9545-9161
2023 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis investigates responses to external cues in oral bacteria on a molecular level. Paper I maps Ser/Thr/Tyr phosphorylated proteins in relation to the general proteome in an oral commensal streptococcus (Streptococcus gordonii DL1). The identified phosphoproteins were involved in various bacterial processes, several associated to dysbiosis and development of biofilm-induced disease. Comparison against phosphoproteomes of other bacteria showed many similarities. This is of interest for the identification of shared phosphorylation profiles. 

Paper II studies differences between the S. gordonii DL1 general proteomes in planktonic and biofilm growth phases, and the regulatory effects of salivary mucin MUC5B on protein expression in the biofilm cells. Regulations in protein expression between the different growth conditions provides insights in bacterial mechanisms for adaptation to the biofilm lifestyle. 

Paper III examines the regulatory roles of salivary MUC5B on biofilm attachment and metabolic output in two clinical isolates of oral commensals, S. gordonii CW and Actinomyces naeslundii CW. S. gordonii facilitated adhesion of A. naeslundii to MUC5B during early attachment. Both bacteria were also able to utilize MUC5B as a sole nutrient source during early biofilm formation, individually and synergistically in a dual species biofilm. The specific responses elicited by MUC5B in paper II-III seem to promote commensal colonization while down-regulating dysbiosis-related biofilm activities. 

Microbiological studies are often focused on dysbiosis and development of disease. However, mechanisms that promote eubiosis are equally important to understand how health can be maintained. Findings associated with responses to external cues in oral bacteria may contribute to future development of novel preventative strategies and identification of predictive biomarkers for oral health. 

Abstract [sv]

Avhandlingen undersöker orala bakteriers svar till utifrån kommande signaler på en molekylärbiologisk nivå. I delarbete I kartläggs proteiner med serin/treonin/ tyrosin fosforylering i relation till det generella proteomet hos en oral streptokock (Streptococcus gordonii DL1). De identifierade fosfoproteinerna kunde kopplas till olika bakteriella processer, varav flera av intresse ur kariessynpunkt. Jämförelse mot andra bakteriers fosfoproteom visade många likheter, vilket är av intresse för identifiering av delade fosforyleringsprofiler. 

I delarbete II undersöks skillnader i det generella proteomet hos S. gordonii DL1 mellan tillväxtfaserna planktonisk och biofilm, samt reglerande effekter av salivmucinet MUC5B på biofilmscellerna proteinuttryck. Skillnaderna i proteinuttryck mellan tillväxtfaser ger ledtrådar om bakteriernas mekanismer för anpassning till biofilmstillväxt. 

Delarbete III studeras salivmucinet MUC5Bs reglerande roll på vidhäftning och metabolism i biofilmer med kliniska isolat av S. gordonii CW samt Actinomyces naeslundii CW. S. gordonii ökade vidhäftningen av A. naeslundii till MUC5B. Båda arterna kunde också använda MUC5B som enda näringskälla under tidig biofilmsbildning, både enskilt och tillsammans. Responserna som MUC5B framkallade i biofilmerna (paper II och III) verkar främja kolonisering av kommensaler och samtidigt nedreglera kariesrelaterade aktiviteter. 

Mikrobiologiska studier fokuserar ofta på dysbiosis och sjukdomsutveckling, men mekanismer som bibehåller eubiosis är minst lika viktiga för att förstå hur oral hälsa kan främjas. Resultat kopplade till orala bakteriers svar på utifrån kommande signaler kan bidra till framtida utveckling av nya strategier för prevention och identifiering av prediktiva biomarkörer för oral hälsa. 

Place, publisher, year, edition, pages
Malmö: Malmö University Press, 2023. , p. 105
Series
Malmö University Odontological Dissertations, ISSN 1650-6065
Keywords [en]
Oral Microbiology, Oral Biofilms, Saliva, Salivary mucin MUC5B, Streptococcus, Actinomyces
National Category
Microbiology Biochemistry and Molecular Biology Cell and Molecular Biology Dentistry
Identifiers
URN: urn:nbn:se:mau:diva-62571DOI: 10.24834/isbn.9789178774180ISBN: 978-91-7877-417-3 (print)ISBN: 978-91-7877-418-0 (electronic)OAI: oai:DiVA.org:mau-62571DiVA, id: diva2:1807514
Public defence
2023-12-08, KL:2370, Carl Gustafs väg 34, Malmö, 09:00 (English)
Opponent
Supervisors
Projects
Foresight
Funder
Swedish Research Council, 201601994NIH (National Institutes of Health), P005403501Available from: 2023-10-27 Created: 2023-10-26 Last updated: 2024-02-23Bibliographically approved
List of papers
1. Intracellular Ser/Thr/Tyr phosphoproteome of the oral commensal Streptococcus gordonii DL1
Open this publication in new window or tab >>Intracellular Ser/Thr/Tyr phosphoproteome of the oral commensal Streptococcus gordonii DL1
2020 (English)In: BMC Microbiology, E-ISSN 1471-2180, Vol. 20, no 1, article id 280Article in journal (Refereed) Published
Abstract [en]

BACKGROUND: To respond and adapt to environmental challenges, prokaryotes regulate cellular processes rapidly and reversibly through protein phosphorylation and dephosphorylation. This study investigates the intracellular proteome and Ser/Thr/Tyr phosphoproteome of the oral commensal Streptococcus gordonii. Intracellular proteins from planktonic cells of S. gordonii DL1 were extracted and subjected to 2D-gel electrophoresis. Proteins in general were visualized using Coomassie Brilliant Blue and T-Rex staining. Phosphorylated proteins were visualized with Pro-Q Diamond Phosphoprotein Gel Stain. Proteins were identified by LC-MS/MS and sequence analysis.

RESULTS: In total, sixty-one intracellular proteins were identified in S. gordonii DL1, many of which occurred at multiple isoelectric points. Nineteen of these proteins were present as one or more Ser/Thr/Tyr phosphorylated form. The identified phosphoproteins turned out to be involved in a variety of cellular processes.

CONCLUSION: Nineteen phosphoproteins involved in various cellular functions were identified in S. gordonii. This is the first time the global intracellular Ser/Thr/Tyr phosphorylation profile has been analysed in an oral streptococcus. Comparison with phosphoproteomes of other species from previous studies showed many similarities. Proteins that are consistently found in a phosphorylated state across several species and growth conditions may represent a core phosphoproteome profile shared by many bacteria.

Place, publisher, year, edition, pages
BioMed Central, 2020
Keywords
2DE, Oral bacteria, Phosphoproteome, Pro-Q diamond, Streptococci, Streptococcus gordonii
National Category
Dentistry
Identifiers
urn:nbn:se:mau:diva-18388 (URN)10.1186/s12866-020-01944-y (DOI)000573079700001 ()32928109 (PubMedID)2-s2.0-85091053882 (Scopus ID)
Available from: 2020-09-24 Created: 2020-09-24 Last updated: 2024-02-05Bibliographically approved
2. Proteomic response in Streptococcus gordonii DL1 biofilm cells during attachment to salivary MUC5B
Open this publication in new window or tab >>Proteomic response in Streptococcus gordonii DL1 biofilm cells during attachment to salivary MUC5B
Show others...
2021 (English)In: Journal of Oral Microbiology, E-ISSN 2000-2297, Vol. 13, no 1, article id 1967636Article in journal (Refereed) Published
Abstract [en]

Background Salivary mucin MUC5B seems to promote biodiversity in dental biofilms, and thereby oral health, for example, by inducing synergistic 'mucolytic' activities in a variety of microbial species that need to cooperate for the release of nutrients from the complex glycoprotein. Knowledge of how early colonizers interact with host salivary proteins is integral to better understand the maturation of putatively harmful oral biofilms and could provide key insights into biofilm physiology. Methods The early oral colonizer Streptococcus gordonii DL1 was grown planktonically and in biofilm flow cell systems with uncoated, MUC5B or low-density salivary protein (LDP) coated surfaces. Bacterial cell proteins were extracted and analyzed using a quantitative mass spectrometry-based workflow, and differentially expressed proteins were identified. Results and conclusions Overall, the proteomic profiles of S. gordonii DL1 were similar across conditions. Six novel biofilm cell proteins and three planktonic proteins absent in all biofilm cultures were identified. These differences may provide insights into mechanisms for adaptation to biofilm growth in this species. Salivary MUC5B also elicited specific responses in the biofilm cell proteome. These regulations may represent mechanisms by which this mucin could promote colonization of the commensal S. gordonii in oral biofilms.

Place, publisher, year, edition, pages
Taylor & Francis, 2021
Keywords
Salivary mucin, MUC5B, oral streptococci, Streptococcus gordonii, oral biofilm, saliva, mass spectrometry, protein expression, proteomics
National Category
Dentistry
Identifiers
urn:nbn:se:mau:diva-45857 (URN)10.1080/20002297.2021.1967636 (DOI)000687414300001 ()34447490 (PubMedID)2-s2.0-85120853173 (Scopus ID)
Available from: 2021-09-14 Created: 2021-09-14 Last updated: 2024-04-16Bibliographically approved
3. Synergistic metabolism of salivary MUC5B in oral commensal bacteria during early biofilm formation
Open this publication in new window or tab >>Synergistic metabolism of salivary MUC5B in oral commensal bacteria during early biofilm formation
Show others...
2023 (English)In: Microbiology Spectrum, E-ISSN 2165-0497, Vol. 11, no 6Article in journal (Refereed) Published
Abstract [en]

Bacterial metabolism in oral biofilms is comprised of complex networks of nutritional chains and biochemical regulations. These processes involve both intraspecies and interspecies networks as well as interactions with components from host saliva, gingival crevicular fluid, and dietary intake. In a previous paper, a large salivary glycoprotein, mucin MUC5B, was suggested to promote a dental health-related phenotype in the oral type strain of Streptococcus gordonii DL1, by regulating bacterial adhesion and protein expression. In this study, nuclear magnetic resonance-based metabolomics was used to examine the effects on the metabolic output of monospecies compared to dual species early biofilms of two clinical strains of oral commensal bacteria, S. gordonii and Actinomyces naeslundii, in the presence of MUC5B. The presence of S. gordonii increased colonization of A. naeslundii on salivary MUC5B, and both commensals were able to utilize MUC5B as a sole nutrient source during early biofilm formation. The metabolomes suggested that the bacteria were able to release mucin carbohydrates from oligosaccharide side chains as well as amino acids from the protein core. Synergistic effects were also seen in the dual species biofilm metabolome compared to the monospecies, indicating that A. naeslundii and S. gordonii cooperated in the degradation of salivary MUC5B. A better understanding of bacterial interactions and salivary-mediated regulation of early dental biofilm activity is meaningful for understanding oral biofilm physiology and may contribute to the development of future prevention strategies for biofilm-induced oral disease.

IMPORTANCE: The study of bacterial interactions and salivary-mediated regulation of early dental biofilm activity is of interest for understanding oral microbial adaptation to environmental cues and biofilm maturation. Findings in oral commensals can prove useful from the perspectives of both oral and systemic health of the host, as well as the understanding of general microbial biofilm physiology. The knowledge may provide a basis for the development of prognostic biomarkers, or development of new treatment strategies, related to oral health and disease and possibly also to other biofilm-induced conditions. The study is also an important step toward developing the methodology for similar studies in other species and/or growth conditions.

Place, publisher, year, edition, pages
ASM International, 2023
Keywords
MUC5B, NMR, actinomyces, bacterial metabolism, biofilm physiology, dental biofilm, metabolomics, oral microbiology, saliva, streptococci
National Category
Dentistry
Identifiers
urn:nbn:se:mau:diva-63213 (URN)10.1128/spectrum.02704-23 (DOI)001085549500001 ()37855449 (PubMedID)2-s2.0-85180007534 (Scopus ID)
Available from: 2023-10-23 Created: 2023-10-23 Last updated: 2024-01-10Bibliographically approved

Open Access in DiVA

fulltext(16988 kB)205 downloads
File information
File name FULLTEXT01.pdfFile size 16988 kBChecksum SHA-512
daf27eb1957998e412090d6de80ca8c3527e1fbd7acabdb4ca77f8cb5e8e51e6bc8e93d2e81a39f19c2f87acd4f0bbde39b93da046b0f0b08915e1e2dff4e02a
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Authority records

Robertsson, Carolina

Search in DiVA

By author/editor
Robertsson, Carolina
By organisation
Faculty of Odontology (OD)Biofilms Research Center for Biointerfaces
MicrobiologyBiochemistry and Molecular BiologyCell and Molecular BiologyDentistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 205 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
isbn
urn-nbn

Altmetric score

doi
isbn
urn-nbn
Total: 1348 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf