Presentation on theme: "F215 control, genomes and environment"— Presentation transcript:
1 F215 control, genomes and environment BiotechnologyF215 control, genomes and environmentModule 2 – Biotechnology and gene technologies
2 Learning OutcomesState that biotechnology is the industrial use of living organisms (or parts of living organisms) to produce food, drugs or other products.Explain why micro organisms are often used in biotechnological processes.
3 BiotechnologyBiotechnology is the industrial use of living organisms to produce food, drugs and other products.Biotechnology has four major applications that affect our livesHealthcare and medical processesAgricultureIndustryFood science
4 Using Micro organismsFeatures of micro organisms that make them suitable for large-scale industrial processesRapid life cyclesReproduce asexuallyVery specific and simple requirements for growthCan be grown on waste materials from industryDoes not raise ethical questionsBacteria have a single copy of each geneSimple control of gene expressionsWide range of metabolic pathwaysSome evolved to survive at high temperatures
5 Learning OutcomesDescribe, with the aid of diagrams, and explain the standard growth curve of a microorganism in a closed culture.
7 Growth curve in a closed culture Lag phaseBacteria adjusting to new conditionsTakes a while for enzyme productionLog phaseNumber of bacteria increase rapidlyStationary PhaseRate of growth is equal to rate of deathDecline PhaseDeath rate is greater than “birth rate”The first three stages represent a sigmoid growth curve
8 Learning OutcomesExplain the importance of manipulating the growing conditions in a fermentation vessel in order to maximise the yield of product required.
9 Large-Scale production Microorganisms are cultured in large containers called fermentersThe growing conditions within the fermenter are manipulated and controlledPrecise growing conditionsTemperatureType and time of the addition of the nutrientOxygen concentrationpH
11 Large scale production Three examples areThe production of penicillinThe production of protease enzymesThe production of mycoprotein
12 Learning OutcomesCompare and contrast the processes of continuous culture and batch culture.Describe the differences between primary and secondary metabolites.
13 Metabolism and metabolites Metabolism (process)Sum total of all the chemical reactionsProcesses produceNew cell and cell componentsChemicalsWaste productsMetabolites (products)A substance produced during cell processes
14 Primary and secondary metabolites Primary metaboliteSubstance produced by organism as part of it’s normal growthE.g. amino acids, proteins, enzymesProduction of primary metabolites matches the growth in populationSecondary metaboliteA substance only produced at a particular growth phaseNo direct involvement in fundamental metabolite processesProduction usually begins after the main growth phase of the micro organisms
15 Batch cultureStarter population is mixed with a specific quantity of nutrient solutionAllowed to grow for a fixed periodProducts removedFermentation tank emptiedExamplesPenicillin productionEnzyme production
16 Continuous CultureNutrients are added and products are removed from the fermentation tank at regular intervalsExamplesInsulin production from genetically modified E.ColiProduction of mycoprotein
17 Learning outcomesExplain the importance of asepsis in the manipulation of microorganisms
18 Asepsis Asepsis Aseptic techniques absence of unwanted microorganisms Any measure taken during a biotechnological process to prevent contamination by unwanted microorganisms
19 The importance of asepsis Unwanted microorganismsCompete with the culture microorganismsReduce the yield of useful productsCause spoilage of the productProduce toxic chemicalsDestroy the culture microorganism or its products.
20 Methods to maintain asepsis Ensure all fermenters and attachments are sterileCleaning with pasteurised steamChemical sterilisationSterilise all liquids, solids and gases that enter the reaction vesselMaintain a pressure difference between the air in the room where fermentation is taking place and outsideMaintains a steady airflow out of the roomEnsure culture of microorganisms is pureEnsure the workers do not introduce unwanted microorganisms from their skin.
21 Learning Outcomes Describe how enzymes can be immobilised. Explain why immobilised enzymes are used in large-scale production.
22 Immobilising enzymes Enzymes act as catalysts in metabolic reactions Enzymes are useful in industrial processesSpecificityTemperature of enzyme actionEnzymes in solution need to be separated from the products.Immobilised enzymes can be re-used many times and leaves the product enzyme free.
23 Methods for immobilising enzymes Gel entrapmentExample – immobilising lactase in alginateStagesEnzyme solution is mixed with sodium alginate solutionDroplets of this solution are added to a solution of calcium chlorideThe droplet turns into a bead which contains the enzyme
25 Immobilising lactase in alginate The beads can be tightly packed into a columnThe liquid substrate can be trickled over the beadsThe product trickles out of the bottom of the columnThe product is collected and purified.
26 Methods of immobilising enzymes Adsorption / carrier boundEnzyme molecules are mixed with immobilising support e.g. glass beads or clayCovalent Bonding / cross-linkedEnzyme molecules covalently bonded to a support
27 Methods of immobilising enzymes Entrapment / inclusionEnzymes trapped in their natural state in a gel beadReaction rate can be reduced as substrate needs to get through the trapping barrierMembrane separationSubstrate separated from the mixture by a partially permeable membrane.
28 Advantages of immobilised enzymes The advantages of using immobilised enzymes over enzymes in solution areImmobilised enzymes can be reusedProduct is enzyme freeImmobilised enzymes are more tolerant to pH and temperature changes