Project description:Streptococcus gallolyticus subsp. gallolyticus is a commensal of the human gastrointestinal tract and a pathogen of infective endocarditis and other biofilm-associated infections with exposed collagen. Therefore, this study focuses on the characterization of the biofilm formation and collagen adhesion of S. gallolyticus subsp. gallolyticus under different conditions. It has been observed that lysozyme triggers biofilm formation divergently in the analyzed S. gallolyticus subsp. gallolyticus strains. The transcriptome analysis was performed for two strains which form more biofilm in the presence of lysozyme. Lysozyme leads to higher expression of genes of transcription and translation, of the dlt operon (cell wall modification), of hydrogen peroxide resistance proteins and of two immunity proteins which could be involved in biofilm formation. Furthermore, the adhesion ability of 73 different S. gallolyticus subsp. gallolyticus strains to collagen type I and IV was analyzed. High adhesion ability was observed for the strain UCN 34, whereas the strain DSM 16831 adhered only marginally to collagen. The full genome microarray analysis revealed strain-dependent gene expression due to adhesion. The expression of genes of a transposon and a phage region in strain DSM 16831 were increased, which corresponds to lateral gene transfer. Adherence to collagen leads to a change in the expression of genes of nutrients uptake in the strain UCN 34.
Project description:Streptococcus gallolyticus subsp. gallolyticus is a commensal of the human gastrointestinal tract and a pathogen of infective endocarditis and other biofilm-associated infections with exposed collagen. Therefore, this study focuses on the characterization of the biofilm formation and collagen adhesion of S. gallolyticus subsp. gallolyticus under different conditions. It has been observed that lysozyme triggers biofilm formation divergently in the analyzed S. gallolyticus subsp. gallolyticus strains. The transcriptome analysis was performed for two strains which form more biofilm in the presence of lysozyme. Lysozyme leads to higher expression of genes of transcription and translation, of the dlt operon (cell wall modification), of hydrogen peroxide resistance proteins and of two immunity proteins which could be involved in biofilm formation. Furthermore, the adhesion ability of 73 different S. gallolyticus subsp. gallolyticus strains to collagen type I and IV was analyzed. High adhesion ability was observed for the strain UCN 34, whereas the strain DSM 16831 adhered only marginally to collagen. The full genome microarray analysis revealed strain-dependent gene expression due to adhesion. The expression of genes of a transposon and a phage region in strain DSM 16831 were increased, which corresponds to lateral gene transfer. Adherence to collagen leads to a change in the expression of genes of nutrients uptake in the strain UCN 34.
Project description:Streptococcus gallolyticus subsp. gallolyticus is a commensal of the human gastrointestinal tract and a pathogen of infective endocarditis and other biofilm-associated infections with exposed collagen. Therefore, this study focuses on the characterization of the biofilm formation and collagen adhesion of S. gallolyticus subsp. gallolyticus under different conditions. It has been observed that lysozyme triggers biofilm formation divergently in the analyzed S. gallolyticus subsp. gallolyticus strains. The transcriptome analysis was performed for two strains which form more biofilm in the presence of lysozyme. Lysozyme leads to higher expression of genes of transcription and translation, of the dlt operon (cell wall modification), of hydrogen peroxide resistance proteins and of two immunity proteins which could be involved in biofilm formation. Furthermore, the adhesion ability of 73 different S. gallolyticus subsp. gallolyticus strains to collagen type I and IV was analyzed. High adhesion ability was observed for the strain UCN 34, whereas the strain DSM 16831 adhered only marginally to collagen. The full genome microarray analysis revealed strain-dependent gene expression due to adhesion. The expression of genes of a transposon and a phage region in strain DSM 16831 were increased, which corresponds to lateral gene transfer. Adherence to collagen leads to a change in the expression of genes of nutrients uptake in the strain UCN 34.
Project description:Streptococcus gallolyticus subsp. gallolyticus is a commensal of the human gastrointestinal tract and a pathogen of infective endocarditis and other biofilm-associated infections with exposed collagen. Therefore, this study focuses on the characterization of the biofilm formation and collagen adhesion of S. gallolyticus subsp. gallolyticus under different conditions. It has been observed that lysozyme triggers biofilm formation divergently in the analyzed S. gallolyticus subsp. gallolyticus strains. The transcriptome analysis was performed for two strains which form more biofilm in the presence of lysozyme. Lysozyme leads to higher expression of genes of transcription and translation, of the dlt operon (cell wall modification), of hydrogen peroxide resistance proteins and of two immunity proteins which could be involved in biofilm formation. Furthermore, the adhesion ability of 73 different S. gallolyticus subsp. gallolyticus strains to collagen type I and IV was analyzed. High adhesion ability was observed for the strain UCN 34, whereas the strain DSM 16831 adhered only marginally to collagen. The full genome microarray analysis revealed strain-dependent gene expression due to adhesion. The expression of genes of a transposon and a phage region in strain DSM 16831 were increased, which corresponds to lateral gene transfer. Adherence to collagen leads to a change in the expression of genes of nutrients uptake in the strain UCN 34.
Project description:Background: Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) is a pathogen of infective endocarditis. It was observed previously that this bacterium survives longer in macrophages than other species and the phagocytic uptake by and survival in THP-1 macrophages is strain-dependent. Methods: The phagocytosis assay was performed with THP-1 macrophages. S. gallolyticus specific whole genome microarrays were used for transcriptome analysis. Results: Better survival in macrophages was observed for UCN34, BAA-2069 and ATCC43143 than for DSM16831 and LMG17956. S. gallolyticus strains show high resistance to tested bactericidal agents (acid, lysozyme and hydrogen peroxide). S. gallolyticus stimulates significant lower cytokine gene expression and causes less lysis of macrophages compared to the control strain S. aureus. S. gallolyticus reacts to oxidative burst with a higher gene expression of NADH oxidase initially at the early phase. Expression of genes involved in D-alanylation of teichoic acid, carbohydrate metabolism and transport systems were upregulated thereafter. Conclusion: S. gallolyticus is very resistant to bactericidal agents normally causing degradation of bacteria in phagolysosomes. Additionally, the D-alanylation of teichoic acid is an important factor for survival.
Project description:Background: Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) is a pathogen of infective endocarditis. It was observed previously that this bacterium survives longer in macrophages than other species and the phagocytic uptake by and survival in THP-1 macrophages is strain-dependent. Methods: The phagocytosis assay was performed with THP-1 macrophages. S. gallolyticus specific whole genome microarrays were used for transcriptome analysis. Results: Better survival in macrophages was observed for UCN34, BAA-2069 and ATCC43143 than for DSM16831 and LMG17956. S. gallolyticus strains show high resistance to tested bactericidal agents (acid, lysozyme and hydrogen peroxide). S. gallolyticus stimulates significant lower cytokine gene expression and causes less lysis of macrophages compared to the control strain S. aureus. S. gallolyticus reacts to oxidative burst with a higher gene expression of NADH oxidase initially at the early phase. Expression of genes involved in D-alanylation of teichoic acid, carbohydrate metabolism and transport systems were upregulated thereafter. Conclusion: S. gallolyticus is very resistant to bactericidal agents normally causing degradation of bacteria in phagolysosomes. Additionally, the D-alanylation of teichoic acid is an important factor for survival.
Project description:Background: Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) is a pathogen of infective endocarditis. It was observed previously that this bacterium survives longer in macrophages than other species and the phagocytic uptake by and survival in THP-1 macrophages is strain-dependent. Methods: The phagocytosis assay was performed with THP-1 macrophages. S. gallolyticus specific whole genome microarrays were used for transcriptome analysis. Results: Better survival in macrophages was observed for UCN34, BAA-2069 and ATCC43143 than for DSM16831 and LMG17956. S. gallolyticus strains show high resistance to tested bactericidal agents (acid, lysozyme and hydrogen peroxide). S. gallolyticus stimulates significant lower cytokine gene expression and causes less lysis of macrophages compared to the control strain S. aureus. S. gallolyticus reacts to oxidative burst with a higher gene expression of NADH oxidase initially at the early phase. Expression of genes involved in D-alanylation of teichoic acid, carbohydrate metabolism and transport systems were upregulated thereafter. Conclusion: S. gallolyticus is very resistant to bactericidal agents normally causing degradation of bacteria in phagolysosomes. Additionally, the D-alanylation of teichoic acid is an important factor for survival.
Project description:Background: Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) is a pathogen of infective endocarditis. It was observed previously that this bacterium survives longer in macrophages than other species and the phagocytic uptake by and survival in THP-1 macrophages is strain-dependent. Methods: The phagocytosis assay was performed with THP-1 macrophages. S. gallolyticus specific whole genome microarrays were used for transcriptome analysis. Results: Better survival in macrophages was observed for UCN34, BAA-2069 and ATCC43143 than for DSM16831 and LMG17956. S. gallolyticus strains show high resistance to tested bactericidal agents (acid, lysozyme and hydrogen peroxide). S. gallolyticus stimulates significant lower cytokine gene expression and causes less lysis of macrophages compared to the control strain S. aureus. S. gallolyticus reacts to oxidative burst with a higher gene expression of NADH oxidase initially at the early phase. Expression of genes involved in D-alanylation of teichoic acid, carbohydrate metabolism and transport systems were upregulated thereafter. Conclusion: S. gallolyticus is very resistant to bactericidal agents normally causing degradation of bacteria in phagolysosomes. Additionally, the D-alanylation of teichoic acid is an important factor for survival.
Project description:Streptococcus gallolyticus subsp. gallolyticus (SGG), an opportunistic gram-positive pathogen responsible for septicemia and endocarditis in the elderly, is often associated with colon cancer (CRC). In this work, we investigated the oncogenic role of SGG strain UCN34 using the azoxymethane (AOM)-induced CRC model in vivo, organoids formation ex vivo and full proteomic and phosphoproteomic analysis from murine colons. To identify SGG-specific pathogenic traits, the choice of the control bacterium was important, and we selected the genetically closest and non-pathogenic relative of SGG named S. gallolyticus subsp. macedonicus (SGM). We showed that SGG UCN34 accelerates colon tumor development in the murine CRC model. To test SGG’s capacity to induce pre-cancerous transformation of the murine colonic epithelium, we grew ex vivo organoids which revealed unusual structures with compact morphology. To understand the molecular changes induced by SGG UCN34, we compared full proteome and phosphoproteome analysis of murine colon chronically colonized by SGG UCN34 or SGM. We found that 136 proteins and 583 phosphorylation sites were differentially regulated following colonization by SGG UCN34. Ingenuity Pathway Analysis (IPA) indicates a pro-tumoral shift induced specifically with SGG UCN34, as most proteins and phosphoproteins identified were associated with digestive cancer. Comprehensive analysis of the altered phosphoproteins using ROMA software revealed possible activation by SGG UCN34 of several cancer hallmark pathways, i.e. MAPK (ERK, JNK and p38), mTOR and integrin/ILK/actin signaling. Altogether, our results reveal for the first time that the oncogenic role of SGG UCN34 is associated with activation of multiple cancer-related signaling pathways which cannot be recapitulated in basic in vitro culture models.