Investigation of Siderophores from Pseudomonas fluorescens

Members:Vamsi MekaJosh HasanShaun PngJohnny YeungInvestigation of the Use of Siderophores from Pseudomonas genus to chelate Heavy Metal ions6/11/2009ProblemArsenic poisoning in the water of Bangladeshi villages and formation of lung cancer in patients caused health problems (Renshaw et al. , 2002). Heavy metal ions are not biodegradable nor thermodegradable and are toxic. (Tansupo et al. , 2009)Metal pollution caused by sources such as motor vehicle emissions, sewage sludge applications, and manufacturing has led to formation of hazardous environments2Background - siderophoresThe property of siderophores in chelating ferric ions have long been known and utilized in scientific industries (Duckworth & Sposito, 2007)Siderophores are produced by bacteria under iron-starved conditions

http://www.biw.kuleuven.be/dtp/cmpg/pgprb_images/PseudoGreen.jpg3HypothesisSiderophores from both Pseudomonas fluorescens and Pseudomonas syringae will demonstrate chelation for nickel, copper(II), iron(III) and lead(II) ionsTemperature and pH for the greatest degree of chelation is 26 degrees Celcius and 7.2 respectively for both species of Pseudomonas

ObjectivesThe objective of the experiment is To investigate chelation of heavy metal ions of copper (II), iron (III), nickel and lead(II) by siderophores from Pseudomonas genusTo find the temperature and pH which allows the greatest degree of chelation.

VariablesIndependentDependentConstantType of heavy metal ionFinal concentration of heavy metal ionsInitial ion concentrationTemperature of incubation of bacteriaInitial bacteria inoculumpHApparatus and MaterialsApparatusMaterialsSpectrophotometerPseudomonas fluorescens ATCC 948MicropipettesPseudomonas syringae Inoculating loop Copper (II) ionsOrbital shakerFerric ions CentrifugeNickel ions Petri dishesLead(II) ions LB mediumMSG mediumProceduresPhase 1: Culturing the bacteriaPart I: Investigating the heavy metal ions that can be chelated:ProceduresSet upMSG medium/broth (Is bacteria present?)Presence of heavy metal ion solution1MSG medium bacteria presentPresent2MSG broth bacteria absentPresent3MSG medium bacteria presentAbsentPhase 2: Preparation of beadsSet up 1: Experimental Set upSet up 2: Determine if concentration of heavy metal ions changes in absence of Pseudomonas bacteriaSet up 3: Determine if heavy metal ions affect growth of Pseudomonas bacteriaIn the experiment, only record the results for set ups 1 and 2 to compare the difference in heavy metal ion concentration.Phase 2: Preparation of sodium alginate beadsMix set ups with sodium alginate solutionPut the mixture dropwise into calcium chloride solution to obtain beads with bacteria inside for set up 1 and 3 but not 2.ProceduresProceduresPart II: Determining optimum temperature for chelation - test only for metal ions that are chelated during Part I

ProceduresPart III: Determining optimum pH for chelationData collectionChange in concentration/ppmThe higher the change, the higher the rate of chelationGraph plottingPlot graphs for 3 different experimentsChange in concentration against type of metalChange in concentration against temperatureChange in concentration against pHStatistical testsConducted with concentration obtained before and after introduction of siderophores from Pseudomonas bacteriap