DOCSLIB.ORG

Pseudomonas Aeruginosa

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Pseudomonas Aeruginosa Physiological and Biochemical Mechanisms of Phenazine- Mediated Survival in Pseudomonas aeruginosa Thesis by Nathaniel Robert Glasser In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy California Institute of Technology Pasadena, California 2017 (Defended April 26, 2017) ii © 2017 Nathaniel Robert Glasser All Rights Reserved iii ACKNOWLEDGEMENTS I owe any accomplishments to my family: to my father, for teaching me a love of math and science; to my mother, for teaching me a love of reading and writing; and to my sister, for grounding me with music and fun. None of my research would be possible without the wonderful group of people Dianne has assembled. To Dianne and all the group members I’ve had the pleasure of working with: Brittany, Caj, Chia, Christian, Dave, David, Elena, Elise, other Elise, Flavia, Gargi, Jessica, Kristy, Kyle, Lina, Lindsey, Lisa, Lucas, Maureen, Megan, Melanie, Michael, Naomi, Nick, Olga, Peter, Ruth, Ryan, Scott, Shannon, Seb, Tahoura, and Will. A special recognition for my co-authors and collaborators: Suzanne, for never giving up; Ben, for your relentless enthusiasm; Julie, for your supernatural calmness; Kyle, for building excellent settlements; and Stuart, for teaching us biologists where to push the electrons. To my human friends, Marissa, Josh, and Paul, and my furry friends, Archimedes and Hypatia, for making game night the highlight of my week; and to Natalie Martin, for bringing me food late at night. And to those with whom I’ve shared invaluable scientific discussions: Ned Ruby, Ian Booth, Nathan Dalleska, Jens Kaiser, Shu-ou Shan, and Andre Hoelz; and finally to my committee, Doug Rees, Jared Leadbetter, and Sarkis Mazmanian. Thank you all! iv ABSTRACT The opportunistic pathogen Pseudomonas aeruginosa secretes a class of colorful redox-active small molecules known as phenazines. Numerous functions have been proposed for phenazines, including antibiotic activity, virulence, cell-to-cell signaling, iron acquisition, and survival. This thesis delves into mechanisms of the latter role, that of long-term survival under oxidant-limiting conditions. Using a diverse array of methods, I investigated how phenazines support survival and how cells transfer electrons to phenazines, as well as the downstream effects that phenazines have on P. aeruginosa. Direct measurements of NAD(H), ATP, the membrane potential, and fermentation products revealed that phenazines promote redox homeostasis and subsequently ATP synthesis. The ATP is used to maintain a membrane potential through the reverse action of the ATP synthase complex. Even though P. aeruginosa does not ferment on sugars, phenazines enable the anaerobic oxidation of glucose to acetate, suggesting P. aeruginosa may have previously under-appreciated metabolic flexibility in the absence of terminal electron acceptors. Activity assays with proteins purified natively from P. aeruginosa showed that glucose oxidation might be enabled in vivo by the pyruvate dehydrogenase complex, which can directly reduce phenazines using pyruvate as an electron donor. Liquid chromatography and mass spectrometry of culture supernatants showed that phenazines alter the chain length distribution of secreted quinolones, which may have indirect downstream signaling effects. Based on this result, combined with data from survival experiments, I hypothesize that phenazine-mediated redox homeostasis promotes β-oxidation and that fatty acid metabolism contributes to long-term survival. Further analysis also showed that P. aeruginosa cultures contain several previously-unreported sulfonated phenazines. In its natural environment, P. aeruginosa undoubtedly encounters other microbial species that consume or modify its phenazines. At least one of these, a Mycobacterium, contains a pyocyanin demethylating v enzyme. The X-ray crystal structure of this protein revealed a novel reaction mechanism wherein the substrate is its own electron acceptor. Together, this work illuminates some of the many ways phenazines shape microbial communities in both clinical and environmental contexts. vi PUBLISHED CONTENT AND CONTRIBUTIONS Glasser, N. R., Saunders, S., and Newman, D. K. (2017) The colorful world of extracellular electron shuttles.Annual Review of Microbiology. In Press. N.R.G. participated in collecting and reviewing the literature, created the figures, and wrote the sections discussing the chemistry and biochemistry of electron shuttling. Glasser, N. R., Kern, S. E., and Newman, D. K. (2014) Phenazine redox cycling enhances anaerobic survival in Pseudomonas aeruginosa by facilitating generation of ATP and a proton- motive force. Molecular Microbiology 92, 399-412. DOI: 10.1111/mmi.12566 N.R.G. collected the data and participated in designing the experiments and writing the manuscript. Glasser, N. R., Wang, B. X., Hoy, J. A., and Newman, D. K. (2017) The pyruvate and α- ketoglutarate dehydrogenase complexes of Pseudomonas aeruginosa catalyze pyocyanin and phenazine-1-carboxylic acid reduction via the subunit dihydrolipoamide dehydrogenase. Journal of Biological Chemistry 292, 5593-5607. DOI: 10.1074/jbc.M116.772848 N.R.G. collected the data, refined the protein structures, wrote the manuscript, and helped design the experiments. Costa, K. C., Glasser, N. R., Conway, S. J., and Newman, D. K. (2017) Pyocyanin degradation by a tautomerizing demethylase inhibits Pseudomonas aeruginosa biofilms. Science 355 (6321), 170- 173. DOI: 10.1126/science.aag3180 N.R.G. assisted with protein crystallization and solving the X-ray crystal structure, and with writing the relevant methods sections of the manuscript. vii TABLE OF CONTENTS Chapter 1 1 Introduction .............................................................................................................................................. 1 Overview ............................................................................................................................................ 3 Literature Cited ................................................................................................................................ 5 Chapter 2 6 Background ............................................................................................................................................... 6 Abstract............................................................................................................................................... 6 Introduction ...................................................................................................................................... 6 Diversity of Endogenous EES and Organisms ........................................................................... 9 Chemical diversity of EES .................................................................................................... 11 Phylogenetic diversity ........................................................................................................... 12 Costs of EES Biosynthesis ........................................................................................................... 15 Cell Biology of Electron Shuttling ............................................................................................. 16 EES in the Extracellular Environment ....................................................................................... 20 Shuttle diffusion ...................................................................................................................... 20 Electron hopping as an alternative to shuttle diffusion .................................................. 22 Evolutionary strategies that maintain EES in open environments ............................... 22 Outlook ........................................................................................................................................... 24 Sidebars ........................................................................................................................................... 25 Sidebar 1. How to characterize a putative EES ................................................................ 25 Sidebar 2. How does redox-potential define an EES? ..................................................... 27 Glossary ........................................................................................................................................... 28 Acknowledgements ....................................................................................................................... 28 Literature Cited ............................................................................................................................. 28 Chapter 3 38 Physiology of Phenazine-Mediated Survival ................................................................................... 38 Abstract............................................................................................................................................ 38 Introduction ................................................................................................................................... 39 Results .............................................................................................................................................. 40 Phenazine redox cycling requires the activity of acetate kinase to promote survival 40 Phenazine redox cycling promotes ATP synthesis during pyruvate fermentation ... 45 ATP synthesis is limited by redox homeostasis during pyruvate fermentation ......... 47 Arginine supports anaerobic
Load more

Recommended publications
  • Extraction and Purification of Pyocyanin: a Simpler and More Reliable Method
    MOJ Toxicology Research Article Open Access Extraction and purification of pyocyanin: a simpler and more reliable method Abstract Volume 4 Issue 6 - 2018 Pyocyanin, the growth pigment produced by Pseudomonas aeruginosa, thought at one time to be a metabolic byproduct, was found to be important for the wellbeing Patrick Abou Raji El Feghali and Tarek Nawas of the organism and one of the important chemicals that allow it to survive in Department of Natural Sciences, Lebanese American University, environments with competitive organisms. Different methods were used to extract Lebanon and purify pyocyanin, some requiring major instruments. This study was performed to introduce an amended method for the optimal extraction and purification of Correspondence: Dr. Tarek Nawas, Department of Natural pyocyanin. The results showed that the maximum yield was obtained from Cetrimide Sciences, School of Arts and Sciences, Lebanese American Agar plates seeded with the organism and held at room temperature for 96 hrs. The University, Beirut, Lebanon, Tel +9611867618, purified pyocyanin’s rate of degradation was dependent on the concentration of the Email sodium hydroxide added, its optimal storage solvents were deionized water and/or Received: December 01, 2018 | Published: December 12, 80% methanol, but not dry chloroform in which the pigment quickly degraded. The 2018 purified pyocyanin was found to be thermolabile as it was stable for many days at lower temperatures but was immediately inactivated by higher temperatures. The suggested method is easy to implement, requires only regular laboratory facilities and gives a good yield of the pure pigment. Recommendations are also provided for proper storage to maintain its activity for a considerable period of time.
    [Show full text]
  • Estudio Molecular De Poblaciones De Pseudomonas Ambientales
    Universitat de les Illes Balears ESTUDIO MOLECULAR DE POBLACIONES DE PSEUDOMONAS AMBIENTALES T E S I S D O C T O R A L DAVID SÁNCHEZ BERMÚDEZ DIRECTORA: ELENA GARCÍA-VALDÉS PUKKITS Departamento de Biología Universitat de les Illes Balears Palma de Mallorca, Septiembre 2013 Universitat de les Illes Balears ESTUDIO MOLECULAR DE POBLACIONES DE PSEUDOMONAS AMBIENTALES Tesis Doctoral presentada por David Sánchez Bermúdez para optar al título de Doctor en el programa Microbiología Ambiental y Biotecnología, de la Universitat de les Illes Balears, bajo la dirección de la Dra. Elena García-Valdés Pukkits. Vo Bo Director de la Tesis El doctorando DRA. ELENA GARCÍA-VALDÉS PUKKITS DAVID SÁNCHEZ BERMÚDEZ Catedrática de Universidad Universitat de les Illes Balears PALMA DE MALLORCA, SEPTIEMBRE 2013 III IV Index Agradecimientos .................................................................................................... IX Resumen ................................................................................................................ 1 Abstract ................................................................................................................... 3 Introduction ............................................................................................................ 5 I.1. The genus Pseudomonas ............................................................................................ 7 I.1.1. Definition ................................................................................................................ 7 I.1.2.
    [Show full text]
  • (Batch Learning Self-Organizing Maps), to the Microbiome Analysis of Ticks
    Title A novel approach, based on BLSOMs (Batch Learning Self-Organizing Maps), to the microbiome analysis of ticks Nakao, Ryo; Abe, Takashi; Nijhof, Ard M; Yamamoto, Seigo; Jongejan, Frans; Ikemura, Toshimichi; Sugimoto, Author(s) Chihiro The ISME Journal, 7(5), 1003-1015 Citation https://doi.org/10.1038/ismej.2012.171 Issue Date 2013-03 Doc URL http://hdl.handle.net/2115/53167 Type article (author version) File Information ISME_Nakao.pdf Instructions for use Hokkaido University Collection of Scholarly and Academic Papers : HUSCAP A novel approach, based on BLSOMs (Batch Learning Self-Organizing Maps), to the microbiome analysis of ticks Ryo Nakao1,a, Takashi Abe2,3,a, Ard M. Nijhof4, Seigo Yamamoto5, Frans Jongejan6,7, Toshimichi Ikemura2, Chihiro Sugimoto1 1Division of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University, Kita-20, Nishi-10, Kita-ku, Sapporo, Hokkaido 001-0020, Japan 2Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga 526-0829, Japan 3Graduate School of Science & Technology, Niigata University, 8050, Igarashi 2-no-cho, Nishi- ku, Niigata 950-2181, Japan 4Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Königsweg 67, 14163 Berlin, Germany 5Miyazaki Prefectural Institute for Public Health and Environment, 2-3-2 Gakuen Kibanadai Nishi, Miyazaki 889-2155, Japan 6Utrecht Centre for Tick-borne Diseases (UCTD), Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands 7Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, 0110 Onderstepoort, South Africa aThese authors contributed equally to this work. Keywords: BLSOMs/emerging diseases/metagenomics/microbiomes/symbionts/ticks Running title: Tick microbiomes revealed by BLSOMs Subject category: Microbe-microbe and microbe-host interactions Abstract Ticks transmit a variety of viral, bacterial and protozoal pathogens, which are often zoonotic.
    [Show full text]
  • Adsorption of Phenazines Produced by Pseudomonas Aeruginosa Using AST-120 Decreases Pyocyanin-Associated Cytotoxicity
    antibiotics Article Adsorption of Phenazines Produced by Pseudomonas aeruginosa Using AST-120 Decreases Pyocyanin-Associated Cytotoxicity Hidetada Hirakawa 1,*, Ayako Takita 1, Motoyuki Uchida 2, Yuka Kaneko 1, Yuto Kakishima 1, Koichi Tanimoto 3, Wataru Kamitani 4 and Haruyoshi Tomita 1,3 1 Department of Bacteriology, Graduate School of Medicine, Gunma University, Maebashi, Gunma 371-8511, Japan; [email protected] (A.T.); [email protected] (Y.K.); [email protected] (Y.K.); [email protected] (H.T.) 2 R&D Strategy & Planning Department, Kureha Corporation, 16 Ochiai, Iwaki, Fukushima 974-8686, Japan; [email protected] 3 Laboratory of Bacterial Drug Resistance, Graduate School of Medicine, Gunma University, Maebashi, Gunma 371-8511, Japan; [email protected] 4 Department of Infectious Diseases and Host Defense, Graduate School of Medicine, Gunma University, Maebashi, Gunma 371-8511, Japan; [email protected] * Correspondence: [email protected] Abstract: AST-120 (Kremezin) is used to treat progressive chronic kidney disease by adsorbing uremic toxin precursors produced by the gut microbiota, such as indole and phenols. Previously, we found that AST-120 decreased drug tolerance and virulence in Escherichia coli by adsorbing indole. Here, we Citation: Hirakawa, H.; Takita, A.; show that AST-120 adsorbs phenazine compounds, such as pyocyanin, produced by Pseudomonas Uchida, M.; Kaneko, Y.; Kakishima, Y.; aeruginosa including multidrug-resistant P. aeruginosa strains, and suppresses pyocyanin-associated Tanimoto, K.; Kamitani, W.; Tomita, toxicity in A-549 (alveolar adenocarcinoma) and Caco-2 (colon adenocarcinoma) cells. Addition of H. Adsorption of Phenazines fosfomycin, colistin and amikacin, which are often used to treat P.
    [Show full text]
  • Downloaded 13 April 2017); Using Diamond
    bioRxiv preprint doi: https://doi.org/10.1101/347021; this version posted June 14, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 2 3 4 5 Re-evaluating the salty divide: phylogenetic specificity of 6 transitions between marine and freshwater systems 7 8 9 10 Sara F. Pavera, Daniel J. Muratorea, Ryan J. Newtonb, Maureen L. Colemana# 11 a 12 Department of the Geophysical Sciences, University of Chicago, Chicago, Illinois, USA 13 b School of Freshwater Sciences, University of Wisconsin Milwaukee, Milwaukee, Wisconsin, USA 14 15 Running title: Marine-freshwater phylogenetic specificity 16 17 #Address correspondence to Maureen Coleman, [email protected] 18 bioRxiv preprint doi: https://doi.org/10.1101/347021; this version posted June 14, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 19 Abstract 20 Marine and freshwater microbial communities are phylogenetically distinct and transitions 21 between habitat types are thought to be infrequent. We compared the phylogenetic diversity of 22 marine and freshwater microorganisms and identified specific lineages exhibiting notably high or 23 low similarity between marine and freshwater ecosystems using a meta-analysis of 16S rRNA 24 gene tag-sequencing datasets. As expected, marine and freshwater microbial communities 25 differed in the relative abundance of major phyla and contained habitat-specific lineages; at the 26 same time, however, many shared taxa were observed in both environments. 27 Betaproteobacteria and Alphaproteobacteria sequences had the highest similarity between 28 marine and freshwater sample pairs.
    [Show full text]
  • Bidirectional Redox Cycling of Phenazine-1-Carboxylic Acid by Citrobacter Portucalensis MBL
    bioRxiv preprint doi: https://doi.org/10.1101/2020.11.23.395335; this version posted November 24, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 1 Bidirectional redox cycling of phenazine-1-carboxylic acid by Citrobacter portucalensis MBL 2 drives increased nitrate reduction 3 4 Lev M. Tsypina and Dianne K. Newmana,b# 5 6 a Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, 7 CA, USA 8 bDivision of Geological and Planetary Sciences, California Institute of Technology, Pasadena, 9 CA, USA 10 11 Running Head: C. portucalensis MBL links PCA and nitrate redox cycles 12 13 # Address correspondence to Dianne K. Newman, [email protected] 14 bioRxiv preprint doi: https://doi.org/10.1101/2020.11.23.395335; this version posted November 24, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 15 ABSTRACT 16 Phenazines are secreted metabolites that microbes use in diverse ways, from quorum sensing to 17 antimicrobial warfare to energy conservation. Phenazines are able to contribute to these activities 18 due to their redox activity. The physiological consequences of cellular phenazine reduction have 19 been extensively studied, but the counterpart phenazine oxidation has been largely overlooked.
    [Show full text]
  • Table S4. Phylogenetic Distribution of Bacterial and Archaea Genomes in Groups A, B, C, D, and X
    Table S4. Phylogenetic distribution of bacterial and archaea genomes in groups A, B, C, D, and X. Group A a: Total number of genomes in the taxon b: Number of group A genomes in the taxon c: Percentage of group A genomes in the taxon a b c cellular organisms 5007 2974 59.4 |__ Bacteria 4769 2935 61.5 | |__ Proteobacteria 1854 1570 84.7 | | |__ Gammaproteobacteria 711 631 88.7 | | | |__ Enterobacterales 112 97 86.6 | | | | |__ Enterobacteriaceae 41 32 78.0 | | | | | |__ unclassified Enterobacteriaceae 13 7 53.8 | | | | |__ Erwiniaceae 30 28 93.3 | | | | | |__ Erwinia 10 10 100.0 | | | | | |__ Buchnera 8 8 100.0 | | | | | | |__ Buchnera aphidicola 8 8 100.0 | | | | | |__ Pantoea 8 8 100.0 | | | | |__ Yersiniaceae 14 14 100.0 | | | | | |__ Serratia 8 8 100.0 | | | | |__ Morganellaceae 13 10 76.9 | | | | |__ Pectobacteriaceae 8 8 100.0 | | | |__ Alteromonadales 94 94 100.0 | | | | |__ Alteromonadaceae 34 34 100.0 | | | | | |__ Marinobacter 12 12 100.0 | | | | |__ Shewanellaceae 17 17 100.0 | | | | | |__ Shewanella 17 17 100.0 | | | | |__ Pseudoalteromonadaceae 16 16 100.0 | | | | | |__ Pseudoalteromonas 15 15 100.0 | | | | |__ Idiomarinaceae 9 9 100.0 | | | | | |__ Idiomarina 9 9 100.0 | | | | |__ Colwelliaceae 6 6 100.0 | | | |__ Pseudomonadales 81 81 100.0 | | | | |__ Moraxellaceae 41 41 100.0 | | | | | |__ Acinetobacter 25 25 100.0 | | | | | |__ Psychrobacter 8 8 100.0 | | | | | |__ Moraxella 6 6 100.0 | | | | |__ Pseudomonadaceae 40 40 100.0 | | | | | |__ Pseudomonas 38 38 100.0 | | | |__ Oceanospirillales 73 72 98.6 | | | | |__ Oceanospirillaceae
    [Show full text]
  • Cetrimide Agar Base M024
    Cetrimide Agar Base M024 Intended use Cetrimide Agar Base is used for the selective isolation of Pseudomonas aeruginosa from clinical specimens. Composition** Ingredients Gms / Litre Gelatin peptone 20.000 Magnesium chloride 1.400 Potassium sulphate 10.000 Cetrimide 0.300 Agar 15.000 Final pH ( at 25°C) 7.2±0.2 **Formula adjusted, standardized to suit performance parameters Directions Suspend 46.7 grams in 1000 ml distilled water containing 10 ml glycerol. Heat, to boiling, to dissolve the medium completely. Sterilize by autoclaving at 15 lbs pressure (121°C) for 15 minutes. Cool to 45-50°C. If desired, rehydrated contents of 1 vial of Nalidixic Selective Supplement (FD130) may be added aseptically to 1000 ml medium. Mix well and pour into sterile Petri plates. Principle And Interpretation Pseudomonas aeruginosa grows well on all normal laboratory media but specific isolation of the organism, from environmental sites or from human, animal or plant sources, is best carried out on a medium, which contains a selective agent and also constituents to enhance pigment production. Most selective media depend upon the intrinsic resistance of the species to various antibacterial agents. Cetrimide inhibits the growth of many microorganisms whilst allowing Pseudomonas aeruginosa to develop typical colonies. Cetrimide is a quaternary ammonium salt, which acts as a cationic detergent that reduces surface tension in the point of contact and has precipitant, complexing and denaturing effects on bacterial membrane proteins. It exhibits inhibitory actions on a wide variety of microorganisms including Pseudomonas species other than Pseudomonas aeruginosa. King et al developed Medium A for the enhancement of pyocyanin production by Pseudomonas (1).
    [Show full text]
  • (12) United States Patent (10) Patent No.: US 6,242,602 B1 Giri Et Al
    USOO62426O2B1 (12) United States Patent (10) Patent No.: US 6,242,602 B1 Giri et al. (45) Date of Patent: Jun. 5, 2001 (54) ONE POTSYNTHESIS OF G. F. Bettinetti et al., “Synthesis of 5, 10-Dialkyl-5, 5,10-DIHYDROPHENAZINE COMPOUNDS 10-dihydrophenazines”, Synthesis, Nov. 1976, pp. 748-749. AND 5,10-SUBSTITUTED DHYDROPHENAZINES B. M. Mikhailov et al., “Metal Compounds of Phenazine and Their Transformations', 1950, Chemical Abstracts, vol. 44, (75) Inventors: Punam Giri; Harlan J. Byker; Kelvin pp. 9452–9453. L. Baumann, all of Holland, MI (US) Axel Kistenmacher et al., “Synthesis of New Soluble Triph (73) Assignee: Gentex Corporation, Zeeland, MI (US) enodithiazines and Investigation of Their Donor Properties”, Chem. Ber, 1992, 125, pp. 1495–1500. (*) Notice: Subject to any disclaimer, the term of this Akira Sugimoto et al., “Preparation and Properties of Elec patent is extended or adjusted under 35 tron Donor Acceptor Complexes of the Compounds Having U.S.C. 154(b) by 0 days. Capto-Dative Substituents', Mar.-Apr. 1989, vol. 26, pp. (21) Appl. No.: 09/280,396 435-438. (22) Filed: Mar. 29, 1999 Primary Examiner Richard L. Raymond (51) Int. Cl." ....................... C07D 241/46; CO7D 241/48 ASSistant Examiner Ben Schroeder (52) U.S. Cl. ............................................. 544/347; 544/347 (74) Attorney, Agent, or Firm-Brian J. Rees; Factor & (58) Field of Search ............................................... 544/347 Partners, LLC (56) References Cited (57) ABSTRACT U.S. PATENT DOCUMENTS Dihydrophenazines and bis(dihydrophenazines) are pre 2,292,808 8/1942 Waterman et al. .................. 260/267 pared in high yield under commercially viable reaction 2,332,179 10/1943 Soule ..................................
    [Show full text]
  • Yu-Chen Ling and John W. Moreau
    Microbial Distribution and Activity in a Coastal Acid Sulfate Soil System Introduction: Bioremediation in Yu-Chen Ling and John W. Moreau coastal acid sulfate soil systems Method A Coastal acid sulfate soil (CASS) systems were School of Earth Sciences, University of Melbourne, Melbourne, VIC 3010, Australia formed when people drained the coastal area Microbial distribution controlled by environmental parameters Microbial activity showed two patterns exposing the soil to the air. Drainage makes iron Microbial structures can be grouped into three zones based on the highest similarity between samples (Fig. 4). Abundant populations, such as Deltaproteobacteria, kept constant activity across tidal cycling, whereas rare sulfides oxidize and release acidity to the These three zones were consistent with their geological background (Fig. 5). Zone 1: Organic horizon, had the populations changed activity response to environmental variations. Activity = cDNA/DNA environment, low pH pore water further dissolved lowest pH value. Zone 2: surface tidal zone, was influenced the most by tidal activity. Zone 3: Sulfuric zone, Abundant populations: the heavy metals. The acidity and toxic metals then Method A Deltaproteobacteria Deltaproteobacteria this area got neutralized the most. contaminate coastal and nearby ecosystems and Method B 1.5 cause environmental problems, such as fish kills, 1.5 decreased rice yields, release of greenhouse gases, Chloroflexi and construction damage. In Australia, there is Gammaproteobacteria Gammaproteobacteria about a $10 billion “legacy” from acid sulfate soils, Chloroflexi even though Australia is only occupied by around 1.0 1.0 Cyanobacteria,@ Acidobacteria Acidobacteria Alphaproteobacteria 18% of the global acid sulfate soils. Chloroplast Zetaproteobacteria Rare populations: Alphaproteobacteria Method A log(RNA(%)+1) Zetaproteobacteria log(RNA(%)+1) Method C Method B 0.5 0.5 Cyanobacteria,@ Bacteroidetes Chloroplast Firmicutes Firmicutes Bacteroidetes Planctomycetes Planctomycetes Ac8nobacteria Fig.
    [Show full text]
  • Characterization of Environmental and Cultivable Antibiotic- Resistant Microbial Communities Associated with Wastewater Treatment
    antibiotics Article Characterization of Environmental and Cultivable Antibiotic- Resistant Microbial Communities Associated with Wastewater Treatment Alicia Sorgen 1, James Johnson 2, Kevin Lambirth 2, Sandra M. Clinton 3 , Molly Redmond 1 , Anthony Fodor 2 and Cynthia Gibas 2,* 1 Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA; [email protected] (A.S.); [email protected] (M.R.) 2 Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, NC 28223, USA; [email protected] (J.J.); [email protected] (K.L.); [email protected] (A.F.) 3 Department of Geography & Earth Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, USA; [email protected] * Correspondence: [email protected]; Tel.: +1-704-687-8378 Abstract: Bacterial resistance to antibiotics is a growing global concern, threatening human and environmental health, particularly among urban populations. Wastewater treatment plants (WWTPs) are thought to be “hotspots” for antibiotic resistance dissemination. The conditions of WWTPs, in conjunction with the persistence of commonly used antibiotics, may favor the selection and transfer of resistance genes among bacterial populations. WWTPs provide an important ecological niche to examine the spread of antibiotic resistance. We used heterotrophic plate count methods to identify Citation: Sorgen, A.; Johnson, J.; phenotypically resistant cultivable portions of these bacterial communities and characterized the Lambirth, K.; Clinton,
    [Show full text]
  • Cetrimide Agar Plates MPH024
    Cetrimide Agar Plates MPH024 For the selection and subculture of Pseudomonas aeruginosa in accordance with the harmonized method of USP/EP/BP/ JP/IP. Composition** Ingredients Gms / Litre Pancreatic digest of gelatin 20.000 Magnesium chloride 1.400 Dipotassium sulphate 10.000 Cetrimide 0.300 Agar 13.600 Glycerol 10 ml **Formula adjusted, standardized to suit performance parameters Directions Either streak, inoculate or surface spread the test inoculum (50-100 CFU) aseptically on the plate. Principle And Interpretation Pseudomonas aeruginosa grows well on all normal laboratory media but specific isolation of the organism, from environmental sites or from human, animal or plant sources, is best carried out on a medium, which contains a selective agent and also constituents to enhance pigment production. Most selective media depend upon the intrinsic resistance of the species to various antibacterial agents. Cetrimide inhibits the growth of many microorganisms whilst allowing Pseudomonas aeruginosa to develop typical colonies. Cetrimide is a quaternary ammonium salt, which acts as a cationic detergent that reduces surface tension in the point of contact and has precipitant, complexing and denaturing effects on bacterial membrane proteins. It exhibits inhibitory actions on a wide variety of microorganisms including Pseudomonas species other than Pseudomonas aeruginosa . King et al developed Medium A for the enhancement of pyocyanin production by Pseudomonas (1). Cetrimide Agar developed by Lowburry (2) is a modification of Tech Agar (Medium A) with addition of 0.1% cetrimide for selective isolation of P. aeruginosa . Later, due to the availability of the highly purified cetrimide, its concentration in the medium was decreased (3).
    [Show full text]