Identification of Proteins Associated with the <i>Pseudomonas aeruginosa</i> Biofilm Extracellular Matrix

Biofilms are surface-associated bacteria that are embedded in a matrix of self-produced polymeric substances (EPSs). The EPS is composed of nucleic acids, polysaccharides, lipids, and proteins. While polysaccharide components have been well studied, the protein content of the matrix is largely unknown. Here we conducted a comprehensive proteomic study to identify proteins associated with the biofilm matrix of <i>Pseudomonas aeruginosa</i> PAO1 (the matrix proteome). This analysis revealed that approximately 30% of the identified matrix proteins were outer membrane proteins, which are also typically found in outer membrane vesicles (OMVs). Electron microscopic inspection confirmed the presence of large amounts of OMVs within the biofilm matrix, supporting previous notions that OMVs are abundant constituents of <i>P. aeruginosa</i> biofilms. Our results demonstrate that while some proteins associated with the <i>P. aeruginosa</i> matrix are derived from secreted proteins and lysed cells, the large majority of the matrix proteins originate from OMVs. Furthermore, we demonstrate that the protein content of planktonic and biofilm OMVs is surprisingly different and may reflect the different physiological states of planktonic and sessile cells

Identification of Proteins Associated with the <i>Pseudomonas aeruginosa</i> Biofilm Extracellular Matrix

Biofilms are surface-associated bacteria that are embedded in a matrix of self-produced polymeric substances (EPSs). The EPS is composed of nucleic acids, polysaccharides, lipids, and proteins. While polysaccharide components have been well studied, the protein content of the matrix is largely unknown. Here we conducted a comprehensive proteomic study to identify proteins associated with the biofilm matrix of <i>Pseudomonas aeruginosa</i> PAO1 (the matrix proteome). This analysis revealed that approximately 30% of the identified matrix proteins were outer membrane proteins, which are also typically found in outer membrane vesicles (OMVs). Electron microscopic inspection confirmed the presence of large amounts of OMVs within the biofilm matrix, supporting previous notions that OMVs are abundant constituents of <i>P. aeruginosa</i> biofilms. Our results demonstrate that while some proteins associated with the <i>P. aeruginosa</i> matrix are derived from secreted proteins and lysed cells, the large majority of the matrix proteins originate from OMVs. Furthermore, we demonstrate that the protein content of planktonic and biofilm OMVs is surprisingly different and may reflect the different physiological states of planktonic and sessile cells

Identification of Proteins Associated with the <i>Pseudomonas aeruginosa</i> Biofilm Extracellular Matrix

Biofilms are surface-associated bacteria that are embedded in a matrix of self-produced polymeric substances (EPSs). The EPS is composed of nucleic acids, polysaccharides, lipids, and proteins. While polysaccharide components have been well studied, the protein content of the matrix is largely unknown. Here we conducted a comprehensive proteomic study to identify proteins associated with the biofilm matrix of <i>Pseudomonas aeruginosa</i> PAO1 (the matrix proteome). This analysis revealed that approximately 30% of the identified matrix proteins were outer membrane proteins, which are also typically found in outer membrane vesicles (OMVs). Electron microscopic inspection confirmed the presence of large amounts of OMVs within the biofilm matrix, supporting previous notions that OMVs are abundant constituents of <i>P. aeruginosa</i> biofilms. Our results demonstrate that while some proteins associated with the <i>P. aeruginosa</i> matrix are derived from secreted proteins and lysed cells, the large majority of the matrix proteins originate from OMVs. Furthermore, we demonstrate that the protein content of planktonic and biofilm OMVs is surprisingly different and may reflect the different physiological states of planktonic and sessile cells

Identification of Proteins Associated with the <i>Pseudomonas aeruginosa</i> Biofilm Extracellular Matrix

Biofilms are surface-associated bacteria that are embedded in a matrix of self-produced polymeric substances (EPSs). The EPS is composed of nucleic acids, polysaccharides, lipids, and proteins. While polysaccharide components have been well studied, the protein content of the matrix is largely unknown. Here we conducted a comprehensive proteomic study to identify proteins associated with the biofilm matrix of <i>Pseudomonas aeruginosa</i> PAO1 (the matrix proteome). This analysis revealed that approximately 30% of the identified matrix proteins were outer membrane proteins, which are also typically found in outer membrane vesicles (OMVs). Electron microscopic inspection confirmed the presence of large amounts of OMVs within the biofilm matrix, supporting previous notions that OMVs are abundant constituents of <i>P. aeruginosa</i> biofilms. Our results demonstrate that while some proteins associated with the <i>P. aeruginosa</i> matrix are derived from secreted proteins and lysed cells, the large majority of the matrix proteins originate from OMVs. Furthermore, we demonstrate that the protein content of planktonic and biofilm OMVs is surprisingly different and may reflect the different physiological states of planktonic and sessile cells

Causes of Transition from Democracy to Totalitarism

Additional file 6: Table S2. Summary of proteins annotated as substrate-binding proteins (SBP) from ATP-binding cassette (ABC) transporters detected in the proteomes of Paenibacillus O199. Annotation was performed with RAST

A Bacterial–Fungal Metaproteomic Analysis Enlightens an Intriguing Multicomponent Interaction in the Rhizosphere of <i>Lactuca sativa</i>

<i>Fusarium oxysporum</i> MSA 35 [wild-type (WT) strain] is an antagonistic isolate that protects plants against pathogenic Fusaria. This strain lives in association with ectosymbiotic bacteria. When cured of the prokaryotic symbionts [cured (CU) form], the fungus is pathogenic, causing wilt symptoms similar to those of <i>F. oxysporum</i> f.sp. <i>lactucae</i>. The aim of this study was to understand if and how the host plant <i>Lactuca sativa</i> contributes to the expression of the antagonistic/pathogenic behaviors of MSA 35 strains. A time-course comparative analysis of the proteomic profiles of WT and CU strains was performed. Fungal proteins expressed during the early stages of plant-fungus interaction were involved in stress defense, energy metabolism, and virulence and were equally induced in both strains. In the late phase of the interkingdom interaction, only CU strain continued the production of virulence- and energy-related proteins. The expression analysis of lettuce genes coding for proteins involved in resistance-related processes corroborated proteomic data by showing that, at the beginning of the interaction, both fungi are perceived by the plant as pathogen. On the contrary, after 8 days, only the CU strain is able to induce plant gene expression. For the first time, it was demonstrated that an antagonistic <i>F. oxysporum</i> behaves initially as pathogen, showing an interesting similarity with other beneficial organisms such as mychorrizae

A Bacterial–Fungal Metaproteomic Analysis Enlightens an Intriguing Multicomponent Interaction in the Rhizosphere of <i>Lactuca sativa</i>

<i>Fusarium oxysporum</i> MSA 35 [wild-type (WT) strain] is an antagonistic isolate that protects plants against pathogenic Fusaria. This strain lives in association with ectosymbiotic bacteria. When cured of the prokaryotic symbionts [cured (CU) form], the fungus is pathogenic, causing wilt symptoms similar to those of <i>F. oxysporum</i> f.sp. <i>lactucae</i>. The aim of this study was to understand if and how the host plant <i>Lactuca sativa</i> contributes to the expression of the antagonistic/pathogenic behaviors of MSA 35 strains. A time-course comparative analysis of the proteomic profiles of WT and CU strains was performed. Fungal proteins expressed during the early stages of plant-fungus interaction were involved in stress defense, energy metabolism, and virulence and were equally induced in both strains. In the late phase of the interkingdom interaction, only CU strain continued the production of virulence- and energy-related proteins. The expression analysis of lettuce genes coding for proteins involved in resistance-related processes corroborated proteomic data by showing that, at the beginning of the interaction, both fungi are perceived by the plant as pathogen. On the contrary, after 8 days, only the CU strain is able to induce plant gene expression. For the first time, it was demonstrated that an antagonistic <i>F. oxysporum</i> behaves initially as pathogen, showing an interesting similarity with other beneficial organisms such as mychorrizae

A Bacterial–Fungal Metaproteomic Analysis Enlightens an Intriguing Multicomponent Interaction in the Rhizosphere of <i>Lactuca sativa</i>

<i>Fusarium oxysporum</i> MSA 35 [wild-type (WT) strain] is an antagonistic isolate that protects plants against pathogenic Fusaria. This strain lives in association with ectosymbiotic bacteria. When cured of the prokaryotic symbionts [cured (CU) form], the fungus is pathogenic, causing wilt symptoms similar to those of <i>F. oxysporum</i> f.sp. <i>lactucae</i>. The aim of this study was to understand if and how the host plant <i>Lactuca sativa</i> contributes to the expression of the antagonistic/pathogenic behaviors of MSA 35 strains. A time-course comparative analysis of the proteomic profiles of WT and CU strains was performed. Fungal proteins expressed during the early stages of plant-fungus interaction were involved in stress defense, energy metabolism, and virulence and were equally induced in both strains. In the late phase of the interkingdom interaction, only CU strain continued the production of virulence- and energy-related proteins. The expression analysis of lettuce genes coding for proteins involved in resistance-related processes corroborated proteomic data by showing that, at the beginning of the interaction, both fungi are perceived by the plant as pathogen. On the contrary, after 8 days, only the CU strain is able to induce plant gene expression. For the first time, it was demonstrated that an antagonistic <i>F. oxysporum</i> behaves initially as pathogen, showing an interesting similarity with other beneficial organisms such as mychorrizae

A Bacterial–Fungal Metaproteomic Analysis Enlightens an Intriguing Multicomponent Interaction in the Rhizosphere of <i>Lactuca sativa</i>

<i>Fusarium oxysporum</i> MSA 35 [wild-type (WT) strain] is an antagonistic isolate that protects plants against pathogenic Fusaria. This strain lives in association with ectosymbiotic bacteria. When cured of the prokaryotic symbionts [cured (CU) form], the fungus is pathogenic, causing wilt symptoms similar to those of <i>F. oxysporum</i> f.sp. <i>lactucae</i>. The aim of this study was to understand if and how the host plant <i>Lactuca sativa</i> contributes to the expression of the antagonistic/pathogenic behaviors of MSA 35 strains. A time-course comparative analysis of the proteomic profiles of WT and CU strains was performed. Fungal proteins expressed during the early stages of plant-fungus interaction were involved in stress defense, energy metabolism, and virulence and were equally induced in both strains. In the late phase of the interkingdom interaction, only CU strain continued the production of virulence- and energy-related proteins. The expression analysis of lettuce genes coding for proteins involved in resistance-related processes corroborated proteomic data by showing that, at the beginning of the interaction, both fungi are perceived by the plant as pathogen. On the contrary, after 8 days, only the CU strain is able to induce plant gene expression. For the first time, it was demonstrated that an antagonistic <i>F. oxysporum</i> behaves initially as pathogen, showing an interesting similarity with other beneficial organisms such as mychorrizae

A Bacterial–Fungal Metaproteomic Analysis Enlightens an Intriguing Multicomponent Interaction in the Rhizosphere of <i>Lactuca sativa</i>

<i>Fusarium oxysporum</i> MSA 35 [wild-type (WT) strain] is an antagonistic isolate that protects plants against pathogenic Fusaria. This strain lives in association with ectosymbiotic bacteria. When cured of the prokaryotic symbionts [cured (CU) form], the fungus is pathogenic, causing wilt symptoms similar to those of <i>F. oxysporum</i> f.sp. <i>lactucae</i>. The aim of this study was to understand if and how the host plant <i>Lactuca sativa</i> contributes to the expression of the antagonistic/pathogenic behaviors of MSA 35 strains. A time-course comparative analysis of the proteomic profiles of WT and CU strains was performed. Fungal proteins expressed during the early stages of plant-fungus interaction were involved in stress defense, energy metabolism, and virulence and were equally induced in both strains. In the late phase of the interkingdom interaction, only CU strain continued the production of virulence- and energy-related proteins. The expression analysis of lettuce genes coding for proteins involved in resistance-related processes corroborated proteomic data by showing that, at the beginning of the interaction, both fungi are perceived by the plant as pathogen. On the contrary, after 8 days, only the CU strain is able to induce plant gene expression. For the first time, it was demonstrated that an antagonistic <i>F. oxysporum</i> behaves initially as pathogen, showing an interesting similarity with other beneficial organisms such as mychorrizae