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In situ evidence for metabolic and chemical microdomains in the structured polymer matrix of bacterial microcolonies
CLSM and fluorescent probes were applied to assess the structure, composition, metabolic activity and gradients within naturally occurring β-proteobacteria microcolonies. Extracellular polymeric substances (EPS) as defined by lectin-binding analyses had three regions: (i) cell associated, (ii) inter...
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| Published in: | FEMS microbiology ecology 2016-11, Vol.92 (11), p.1 |
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| container_title | FEMS microbiology ecology |
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| creator | Lawrence, J. R. Swerhone, G. D. W. Kuhlicke, U. Neu, T. R. |
| description | CLSM and fluorescent probes were applied to assess the structure, composition, metabolic activity and gradients within naturally occurring β-proteobacteria microcolonies. Extracellular polymeric substances (EPS) as defined by lectin-binding analyses had three regions: (i) cell associated, (ii) intercellular and (iii) an outer layer covering the entire colony. We assessed structural, microenvironmental and metabolic implications of this complex EPS structure. Permeability studies indicated that the outer two layers were permeable to 20 nm beads, intercellular EPS to |
| doi_str_mv | 10.1093/femsec/fiw183 |
| format | article |
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Fluorescent reporters and CLSM were applied to address the hypothesis that the exopolymeric matrix of microcolonies functions to create a series of microdomains that result in unitary structure and function.</description><identifier>ISSN: 1574-6941</identifier><identifier>ISSN: 0168-6496</identifier><identifier>EISSN: 1574-6941</identifier><identifier>DOI: 10.1093/femsec/fiw183</identifier><identifier>PMID: 27562775</identifier><language>eng</language><publisher>England: Oxford University Press</publisher><subject>Bacteria ; Beads ; Betaproteobacteria - enzymology ; Betaproteobacteria - metabolism ; Betaproteobacteria - physiology ; Biofilms - growth & development ; Cell Membrane - chemistry ; Cell surface ; Cellular Microenvironment - physiology ; Chemical properties ; Chlorides ; Colonies ; Concentration gradient ; Ecology ; Fluorescence ; Fluorescent Dyes ; Fluorescent indicators ; Glucose oxidase ; Membrane Microdomains - chemistry ; Metabolism ; Microbial colonies ; Microbial metabolism ; Microbiological research ; Microbiology ; Microscopy, Confocal ; Nutrients ; Permeability ; pH effects ; Phosphoric Monoester Hydrolases - metabolism ; Physiological aspects ; Polymeric composites ; Polymers ; Polymers - chemistry ; Potassium chloride ; Potassium Cyanide - chemistry ; Rhodamine ; Structure-function relationships</subject><ispartof>FEMS microbiology ecology, 2016-11, Vol.92 (11), p.1</ispartof><rights>FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com 2016</rights><rights>FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.</rights><rights>COPYRIGHT 2016 Oxford University Press</rights><rights>Copyright Oxford University Press, UK Nov 2016</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c421t-137517764928bcd0b6a05a994cf0e2fe1295a7d9b45cdd5959818e71b700edc3</citedby><cites>FETCH-LOGICAL-c421t-137517764928bcd0b6a05a994cf0e2fe1295a7d9b45cdd5959818e71b700edc3</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>314,780,784,1603,27923,27924</link.rule.ids><linktorsrc>$$Uhttps://dx.doi.org/10.1093/femsec/fiw183$$EView_record_in_Oxford_University_Press$$FView_record_in_$$GOxford_University_Press</linktorsrc><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/27562775$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><contributor>Nakatsu, Cindy</contributor><creatorcontrib>Lawrence, J. R.</creatorcontrib><creatorcontrib>Swerhone, G. D. W.</creatorcontrib><creatorcontrib>Kuhlicke, U.</creatorcontrib><creatorcontrib>Neu, T. R.</creatorcontrib><title>In situ evidence for metabolic and chemical microdomains in the structured polymer matrix of bacterial microcolonies</title><title>FEMS microbiology ecology</title><addtitle>FEMS Microbiol Ecol</addtitle><description>CLSM and fluorescent probes were applied to assess the structure, composition, metabolic activity and gradients within naturally occurring β-proteobacteria microcolonies. Extracellular polymeric substances (EPS) as defined by lectin-binding analyses had three regions: (i) cell associated, (ii) intercellular and (iii) an outer layer covering the entire colony. We assessed structural, microenvironmental and metabolic implications of this complex EPS structure. Permeability studies indicated that the outer two layers were permeable to 20 nm beads, intercellular EPS to <40 nm beads and the outer layer was permeable to <100 nm beads. Phosphatase activity occurred at the cell surface and associated polymer. Glucose oxidase activity was only detected inside the cells and the cell-associated polymer. Rhodamine 123 suggested that activity was highest near the cell surface. The potential sensitive dye JC-1 concentrated within the outer EPS layer and the gradient was responsive to inhibition by KCN, dispersion using KCl and enhanced by addition of nutrients (nutrient broth). pH gradients occurred from the cell interior (pH 7) to the microcolony interior (pH 4+) with a gradient of increasing pH (pH 7+) to the colony exterior. The EPS provides a physical and chemical structuring mechanism forming microdomains that segregate extracellular activities at the microscale, possibly resulting in a microcolony with unitary structure and function.
Fluorescent reporters and CLSM were applied to address the hypothesis that the exopolymeric matrix of microcolonies functions to create a series of microdomains that result in unitary structure and function.</description><subject>Bacteria</subject><subject>Beads</subject><subject>Betaproteobacteria - enzymology</subject><subject>Betaproteobacteria - metabolism</subject><subject>Betaproteobacteria - physiology</subject><subject>Biofilms - growth & development</subject><subject>Cell Membrane - chemistry</subject><subject>Cell surface</subject><subject>Cellular Microenvironment - physiology</subject><subject>Chemical properties</subject><subject>Chlorides</subject><subject>Colonies</subject><subject>Concentration gradient</subject><subject>Ecology</subject><subject>Fluorescence</subject><subject>Fluorescent Dyes</subject><subject>Fluorescent indicators</subject><subject>Glucose oxidase</subject><subject>Membrane Microdomains - chemistry</subject><subject>Metabolism</subject><subject>Microbial colonies</subject><subject>Microbial metabolism</subject><subject>Microbiological research</subject><subject>Microbiology</subject><subject>Microscopy, Confocal</subject><subject>Nutrients</subject><subject>Permeability</subject><subject>pH effects</subject><subject>Phosphoric Monoester Hydrolases - metabolism</subject><subject>Physiological aspects</subject><subject>Polymeric composites</subject><subject>Polymers</subject><subject>Polymers - chemistry</subject><subject>Potassium chloride</subject><subject>Potassium Cyanide - chemistry</subject><subject>Rhodamine</subject><subject>Structure-function relationships</subject><issn>1574-6941</issn><issn>0168-6496</issn><issn>1574-6941</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2016</creationdate><recordtype>article</recordtype><recordid>eNqFkc1rFTEUxYMotlaXbiXgxs20uTOTSbIsxY9CwU33IZPc2JSZ5Jlk1P735vFaqyJIILmE3zncew8hr4GdAlPDmce1oD3z4TvI4Qk5Bi7GblIjPP2tPiIvSrllDPgwsufkqBd86oXgx6ReRlpC3Sh-Cw6jRepTpitWM6clWGqio_YG12DNQtudk0urCbHQEGm9QVpq3mzdMjq6S8vdik1tag4_aPJ0NrZiDg9Sm5YUA5aX5Jk3S8FX9-8Juf7w_vriU3f1-ePlxflVZ8ceageD4CDENKpeztaxeTKMG6VG6xn2HqFX3Ain5pFb57jiSoJEAbNgDJ0dTsi7g-0up68blqrXUCwui4mYtqJB9iBUryRr6Nu_0Nu05dia06AU40IJyR-pL2ZBHaJPNRu7N9XngkkBcpymRp3-g2rH7deYIvrQ_v8QdAdBW1EpGb3e5bCafKeB6X3I-hCyPoTc-Df3zW7ziu4X_ZDq4-Bp2_3H6yenYLIh</recordid><startdate>20161101</startdate><enddate>20161101</enddate><creator>Lawrence, J. 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R.</au><au>Swerhone, G. D. W.</au><au>Kuhlicke, U.</au><au>Neu, T. R.</au><au>Nakatsu, Cindy</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>In situ evidence for metabolic and chemical microdomains in the structured polymer matrix of bacterial microcolonies</atitle><jtitle>FEMS microbiology ecology</jtitle><addtitle>FEMS Microbiol Ecol</addtitle><date>2016-11-01</date><risdate>2016</risdate><volume>92</volume><issue>11</issue><spage>1</spage><pages>1-</pages><issn>1574-6941</issn><issn>0168-6496</issn><eissn>1574-6941</eissn><abstract>CLSM and fluorescent probes were applied to assess the structure, composition, metabolic activity and gradients within naturally occurring β-proteobacteria microcolonies. Extracellular polymeric substances (EPS) as defined by lectin-binding analyses had three regions: (i) cell associated, (ii) intercellular and (iii) an outer layer covering the entire colony. We assessed structural, microenvironmental and metabolic implications of this complex EPS structure. Permeability studies indicated that the outer two layers were permeable to 20 nm beads, intercellular EPS to <40 nm beads and the outer layer was permeable to <100 nm beads. Phosphatase activity occurred at the cell surface and associated polymer. Glucose oxidase activity was only detected inside the cells and the cell-associated polymer. Rhodamine 123 suggested that activity was highest near the cell surface. The potential sensitive dye JC-1 concentrated within the outer EPS layer and the gradient was responsive to inhibition by KCN, dispersion using KCl and enhanced by addition of nutrients (nutrient broth). pH gradients occurred from the cell interior (pH 7) to the microcolony interior (pH 4+) with a gradient of increasing pH (pH 7+) to the colony exterior. The EPS provides a physical and chemical structuring mechanism forming microdomains that segregate extracellular activities at the microscale, possibly resulting in a microcolony with unitary structure and function.
Fluorescent reporters and CLSM were applied to address the hypothesis that the exopolymeric matrix of microcolonies functions to create a series of microdomains that result in unitary structure and function.</abstract><cop>England</cop><pub>Oxford University Press</pub><pmid>27562775</pmid><doi>10.1093/femsec/fiw183</doi></addata></record> |
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| subjects | Bacteria Beads Betaproteobacteria - enzymology Betaproteobacteria - metabolism Betaproteobacteria - physiology Biofilms - growth & development Cell Membrane - chemistry Cell surface Cellular Microenvironment - physiology Chemical properties Chlorides Colonies Concentration gradient Ecology Fluorescence Fluorescent Dyes Fluorescent indicators Glucose oxidase Membrane Microdomains - chemistry Metabolism Microbial colonies Microbial metabolism Microbiological research Microbiology Microscopy, Confocal Nutrients Permeability pH effects Phosphoric Monoester Hydrolases - metabolism Physiological aspects Polymeric composites Polymers Polymers - chemistry Potassium chloride Potassium Cyanide - chemistry Rhodamine Structure-function relationships |
| title | In situ evidence for metabolic and chemical microdomains in the structured polymer matrix of bacterial microcolonies |
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