2 What are the Fungi? Simple eukaryotic organisms with small genomes Reproduce asexually and sexually by sporesHeterotrophs: similar to animals, many bacteria, they rely on autotrophic organisms for fixed carbon and nitrogenFilamentous growth (threadlike strands called hyphae), often branching. Growth of hyphae is at tips. Exception: yeasts which are unicellular. Fungi don't have stems, leaves, roots nor a vascular system like plants.Easy to grow in the lab on defined media (like bacteria), make mutants and do genetic crossesMany species are well developed for molecular manipulations: Transformation, gene replacement, regulated gene expression
9 What Are Fungi Doing? Decomposers Saprobes are the primary agents for biodegradation of plants and woody debris~85 billion tons of carbon as CO2 are returned to the atmosphere annuallyDisease Agents: decay of living materialPlant pathogens destroy ~3 billion dollars of crops annually in N. AmericaAnimal pathogensin Arizona alone, the Valley Fever fungus is responsible for $29 million in hospital costs annually
11 Chicago Worlds Fair - Human hair growing on But Fungi are not humanChicago Worlds Fair - Human hair growing onWood, Believe it Or Not
12 Fungi in History- First observation Rusts were observed by Romans on cereals~370 BCthey created a rust God, Robigo to pray for deliverance from disease
13 More History-why the British drink tea instead of coffee Until 1870’s, Coffee was produced in Ceylon (Sri Lanka)Britian was full of Coffee housesCoffee rust (Hemileia vastatrix) swept through the coffee plantations betweenCoffee growers switched to tea and rubberCoffee production moved to Central and South America
14 Fungi in History- the Irish move to America mid-1840’s Potato crops fail in Ireland2 million people died, 1 million emigrated to US1861 deBary shows this was due to a “fungus”, Phytophthora infestansan emerging problem today due to a new strain
15 Fungi in History-Salem Witch Trials In 1692 several women in Salem, MA were accused of witchcraft and hungEvidence suggests their “strange behavior” may have been due to poisoning by the ergot fungus, Claviceps purpurea, a pathogen of ryeThis fungus produces toxins (alkaloids) that cause vasoconstriction.It is the source of LSDCan lead to cutting off of the blood supply and loss of limbs due to gangrene setting inSome of its alkaloids are used for treatment of migranes, and induction of labor during childbirth
16 Fungi- The New Asbestos? New York TimesMagazine -August 12, 2001
17 Stachybotrys chartarum The sick building mold??????
18 Why are fungi important organisms for biotechnology? Produce 1o and 2o metabolites of industrial importance1o metabolites: end products of common metabolic pathways:alcohol (ethanol), citric acid, itaconic acid2o metabolites: a diverse range of compounds that lack known obvious functions in the growth and reproduction of the organism.Production often occurs after growth has stopped, when nutrients are limited, but excess carbon is available.ex: Penicillin, cephalosporins, griseofulvin, cyclosporin, ergot alkaloidsWell developed and understood secretory machinery allowing simple purification of products from culture medium.Relatively easily grown in mass culture and lots of practice (alcoholic beverage industry).
19 Manipulability of Fungi makes them attractive to industry Easy to grow, make mutants and do genetic crossesMolecular biology is well developed: transformation, gene replacement, regulated expression, total genome expression analysis, whole genome sequences are becoming availableSaccharomyces cerevisiae was the first eukaryote to have its full genome sequenced (1996), Neurospora crassa (2001), several others in 2002
20 Saccharomyces cerevisiae: the brewers and bakers yeast A facultative anaerobeAnaerobic respiration: produces alcoholC6H12O > 2C2H5OH + 2CO2 + 2 ATPAerobic respiration: major product is CO2C6H12O > 6 CO2 + 6 H ATPOne of the first organism’s exploited for biotechnologyWheat production resulted in the settling of populationsYeast was responsible for making bread rise
21 Fungi were the source of the first antibiotic Penicillium notatum
22 The Penicillin Story Antibiotic production 1929: Discovered P. notatum as a contaminant on a bacterial plate by A. Fleming1939: Chain and Florey first isolated drug to treat mice and a dying patient1940’s: Florey and others worked on production for treatment of bacterial infections during WWIIProduction Improvements:New species ID’ed: P. chrysogenum on a moldy cantelope in a Peoria, IL marketCulturing conditions: corn steeping liquor gave a 40X yield increaseMutagenesis and selection increased production from 80 mg/L to 7 g/LSynthetic modification of side chains produced more stable and effective drugs (ampicillin, carbenicillin)
23 Penicillin- the first antibiotic Fleming’s 1929 plate
24 Quorn- eaten in the UK for 17 years, now available in the US Fusarium graminearum, isolated from a field in Marlow, BuckinghamshireQuorn is produced from mycelia grown in 155,000 litre airlift fermentersThe filamentous nature of the biomass is responsible for the meat-like texture and appearance of the final product.Probably the most thoroughly tested food ever to appear on supermarket shelves, annual sales of Quorn are now in excess of £15 million in the UK.
25 “Quorn”-meat-free www.quorn.com Quorn products typically contain between 11 to 15 grams of protein per 100 grams,most of which comes from mycoprotein.
26 Citric acid isolated, from a fungus, is everywhere Citric acid production is from the fungus Aspergillus nigerProduction is due to blockage of the TCA cycle by growing A. niger under low pH conditions with enzyme inhibitors like Cu ions1979, more than 100 million kilograms were produced in US and EuropeFound as a flavoring (soft drinks, candies, desserts, jams jellies, wines, frozen fruits, also in gelatinscitrates in blood transfusions act as anti-coagulantsAdjusts pH in hair rinses, hair dyes, used in creams and ointmentsZinc citrate in toothpaste is a plaque inhibitor
30 What Is Valley Fever? Caused by a soil fungus Other names: Coccidioides immitis(Coccidium-like not mild)Other names:Coccidioidomycosis (cocci)Desert RheumatismInfection results from inhaling arthroconidiaSeverity variesMild: 60%Moderate: 30%Complicated: 10%After infection, most persons develop life-long immunity
32 Valley Fever in the U.S. % Positive Skin Test 50-70 30-50 10-30 5-10 <5
33 Coccidioidomycosis in Arizona (Reported)- a problem on the rise
34 High Profile Cases Woods’ ills caused by Valley Fever By SUSAN CARROLLCitizen Staff Writer__ ___________Loren Wood’s lamented absencefrom the NCAA Tournament, his twoback surgeries and upcoming monthsof physical therapy are being blamedon one culprit: valley fever.TUCSON CITIZEN: May 5, 2000