Biology of FUNgi. Last time...

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1 Biology of FUNgi Lecture 17 Tangled destinies Fungi rule human evolution and migration Last time... Phlebia and Heterobasidion antagonistic associations among fungi. The predators of amoeba. Trichoderma predator of fungi Mutualisms with bacteria: Chantarellus, Pseudomonas and the big trees. Fungal parasites of other fungi: Hypomyces. 1

2 Fungi of the day - Taxonomy: Phylum (subphylum) Basidiomycota Order - Agaricales Family - Strophariaceae Psilocybe cubensis with distinctly umbonate cap and a distinct annulus Genus Psilocybe is known commonly as the liberty caps or magic mushrooms. They are characterized by black spores and blueing reaction of the stipe when handled. Psilocybe cyanescens is another hallusinogenic psilocybe Boletus calopus and B. erythripus show blue-stain reaction Fungi of the day - Like many other Strophariaceae, species of Psilocybe are common LBMs and are mainly saprotrophic on various substrates. P. cyanescens can often be found on decaying wood, P. cubensis is a common fungus on pastures and seem to enjoy cow pies as main substrate. Psilocybe cyanescens on wood chips and P. cubensis on dung 2

3 Fungi of the day - How did we come to know about Psilocybes? In the 1940 s and 1950 s a new branch of mycology - etnomycology - was founded (Gordon and Wasson) as a group of anthropologists traveled in southern Mexico and discovered that some of the natives were consuming sacred or magical mushrooms in spiritual gatherings. Is it a coincidence that Alice in wonderland is displayed with mushrooms? Chemicals in Psilocybes may cause you to se funny things Fungi of the day - How did we come to know about Psilocybes? The sacred fungi led to contact with either ancient spirits or gods themselves. With the assistance of a clever mycologist (Roger Heim), Gordon and Wasson were able to conclude that the sacred mushrooms were several species in the genus Psilocybe. The Psilocybes were mainly characterized by their inconspicuousness - they were your garden variety of LBMs. Psilocybe cubensis was among the initial sacred shrooms in Mexico. Another one would have been Psilocybe mexicana. 3

4 Fungi of the day - Psilocybe cyanescens Some, not all, Psilocybes are hallucinogenic, i.e., make you see things, sometimes not-so-very-good things. The hallucinogenic activity of the Psilocybes is due to two related compounds psilocybin and psilocin. Psilocin is very similar to the human neurotransmitter molecule serotonin; a likely explanation for the hallucinogenic activity. Serotonin and psilocin differ only by the location of hydroxy and addition of a short ethyl (CH 3 ) 2 group. Fungi of the day - Of the two active incredients, psilocin was more potent and structurally somewhat similar to serotonin and replaces serotonin in brain. It appears that psilocybin is altered to psilocin in human body. Psilocybin being a mind-altering drug, like LSD, an interest for using psilocin as a therapeutic psyche drug emerged. Claviceps alkaloids (recall LSD), psilocin and psilocybin affect the nervous system Serotonin and psilocin differ only by the location of hydroxy and addition of a short ethyl (CH 3 ) 2 group. 4

5 Fungi of the day - Timothy Leary, a newly appointed director of the Center for Research in Personality, Harvard University, got interested in psilocin. Timothy Leary, a Harvard Psilocin could be synthesized and the same professor and a revolutionary of company which supplied LSD (Sandoz his time. Pharmaceutical in Switzerland) was willing to supply dedicated scientists with experimental material. Leary s research with psilocin was expanded to include graduate students at Harvard. It pays to go to grad school! Unfortunately, Leary started to experiment with LSD as well as psilocin; Harvard became infamous for its focus on hallucinogenic drugs. Soon, restrictions on Leary s research were tightened and his relationships with his colleagues deteriorated. He was eventually fired from Harvard. Fungi of the day - Despite the controversies, Leary continued his exploration (research?) on the connections between the mind-altering drugs and consciousness. As a result of his interests he became a hero and somewhat an authority among those who see need to explore the depths of their minds. 5

6 Fungi of the day - Not surprisingly, others picked on the importance of the hallucinogenic mushrooms. A remarkable example is Terence McKenna who had a BA in shamanism and conservation of natural resources from University of California in Berkeley. McKenna argued that the relatively rapid social and intellectual evolution of human beings was powered by conscious or accidental consumption of mindbroadening fungi. Terence McKenna Fungi of the day - McKenna built his argument around the fact that being collectors and foraging in the plains or woods, the early humans inevitably came in contact with fungi that might have the compounds capable of altering minds. His argument continues by pointing out that at low doses psilocin may heighten senses - therefore you d be a better hunter under their influence. When game was plentiful, being a more efficient hunter would allow you to spare more time for intellectual growth. On the other hand, if the game was sparse, the same group of early primates would have been the ones to survive. Terrence McKenna You should be the judge of the credibility of McKenna s arguments. 6

7 This time... There was an evolutionary argument how fungi made humans smart; pick your side. Reminder: penicillin We will now look more into factual affect of fungi on human migration. Reminder: penicillin discovery and its effect on human lives Penicillium notatum colonized Fleming s Staphylocuccus cultures in After clinical tests and great deal of product development and engineering, enough could be made available for the allied troops to save many allied soldier s lives. Penicillium sp... This may have expedited the end of WWII in Europe like the nuke did in the Pacific. Recall that death from infections accounted for 15% of total loss of troops in WWI, these were nearly absent towards the end of WWII. and sir Alexander Fleming, whose Staphylococcus plates were contaminated. 7

8 Phytophthora infestans and Phytophthora infestans is the causal agent of potato blight. P. infestans is also the cause of the great Irish famine, which resulted in the great Irish migration to North America. Phytophthora infestans. - zoosporangia. A zoospore with tinsel and whiplash flagellum Phytophthora infestans and A reminder: Phytophthora is an oomycete. Reproduction by biflagellated zoospores, which are borne in zoosporangia. Phytophthora infestans. - zoosporangium. A biflagellated zoospore with tinsel and whiplash flagellum 8

9 Phytophthora infestans and Phytophthora infestans zoospores colonize potato roots and tubers in soil. The colonization decreases the overall growth of the potato plant, yield of potatoes and destroys the taters in storage. Foliar necrosis resulting from potato blight Taters infected with Phytophthora infestans (soft rot) Phytophthora infestans and Uncontrolled, Phytophthora infestans zoospores can colonize and decimate the entire crop of potatoes. This is what the whole Irish famine is all about. Substantial loss of crops and its direct and indirect outcomes. A potato field leveled by blight Foliar necrosis of potatoes. 9

10 Phytophthora infestans and Potatoes were the primary source of nutrition for the poor in Ireland. Weather in the summers 1845 and 1846 was particularly favorable for Phytophthora infestans. Lots of rain and fairly low temperatures. Rain and abundant moisture facilitated the rapid dispersal and great abundance of Phytophthora infestans. Taters were the primary food source for the Irish farmers Phytophthora infestans and In , the subsistence level farmers found that their tater supply was rotting in the cellars. Nobody s tater crops were doing well and the price of food sky-rocketed. Eating became a luxury that everybody could not afford; famine is also known as the great hunger. Taters were the primary food source for the Irish farmers 10

11 Phytophthora infestans and As a result of the poor crops, the British and Protestant landlords evicted farmers from their land. People were forced to move into overpopulated workhouses. With nothing else to eat, many chose to eat the rotted taters. This and the living arrangements resulted in increase in cholera and typhus. Entire villages were decimated. With little choice, many ate rotten potatoes and got sick. Phytophthora infestans and Some landlords were more humane and paid for emigration to English-speaking countries. The Irish peasants were loaded on ships called fondly as the coffin vessels. As many as 30% of those who were on board of the coffin vessels never came to the port at the other end. Evicted and homeless, many chose to emigrate if the finances allowed. 11

12 Phytophthora infestans and Combined with the emigration largely spurred by, the vast Phytophthora infection caused the Irish population to fall to 5 from 8 million. In addition to causing ca. 1 million deaths, structured the American population and shaped American history (20% claim Irish ancestry). For example, orphan trains from New Orleans and New York transported Irish orphans to be adopted by Kansas farmers. Phytophthora infestans and New epidemics of Phytophthora infestans hit Ireland again in 1872 and However, by then the Irish poor farmers had found additional food supplements (imported corn) and were not as dependent on potatoes. By 1890, we also had learned that Phytophthora infestans could be virtually eliminated with copper sulphate (Bordeaux mixture). With little choice, many ate rotten potatoes and got sick. 12

13 Phytophthora infestans and WWI In 1914, German Kaiser s high command ordered all surplus food to be stored in the cities for safe keeping. Few bad potatoes ruined massive amounts of stored food. Phytophthora infestans hit again in 1915 and 1916 resulting ca 700,000 German casualties. It has been argued that weakened home front had taken a toll on Germans and the allied victory had been assured by 1917 when British and Americans got involved. Phytophthora infestans and How to manage for the Phytophthora infestans? Use more resistant varieties. Use systemic fungicides (e.g. Metalaxyl or Bordeaux mixture [copper sulfate and calcium oxide]) to prevent infestation in advance. 13

14 Summary Mind-influencing fungi and their effect on the human evolution. Phytophthora infestans - its influence on Irish and American history as well as on outcomes of WW I. 14