WEEK 2 1 Fungi are the most important organisms on the planet Why On the Final a Recycle carbon b Make beer cheese cures meat eat mushrooms Make foods c Can be used for toxins but also beneficial medicines d Can make dyes e Out of body religious experiences Hallucinogens f Spoil food products Decompose g Food for mammals h Pathogens of humans and plants i Top 5 threats of food supply j Bio fuels Fungus of the Day Fungi are a part of some wood that are used for violins Actually make it sound better Stradivarius It doesn t break down the cell walls or make them collapse so they are still able to be used Basic Function that must all Fungi do 1 Find food source and absorb it 2 Find a suitable environment generally having moisture 3 Reproduce Can be sexual reproduction 4 Find a mate Mushroom example 5 Disseminate Spread spores around Protect themselves Ward off other fungi so they don t take your nutrients Some Fungi live forever continue to grow Mycology Study of fungi Over 100 000 of fungi discovered Also a lot of fungi that cannot grow on petri dish Probably actually 10 Million Characteristics of True Fungi Ubiquitous Eukaryotic Achorophylus Cant make food have to get it from somewhere else Heterotrophic Must have organic matter carbon to get nutrients Reproduce by spores No vascular system Grow like a yeast Of the Known Fungi Can not get sick from them oo1 are human pathogens Also animals 15 of fungi are pathogens of plants Rest are saprobes 25 of the stuff on earth biomass Fungi are good and bad Mutualists Help eachother Parasites Attack what they are growing on Mycellium Body of the funguse 2 growth types Fillamentous Growth is polarized Allows you to grow many directions all mycelial growth starts at the tip and moves forward Yeast Unicelluar Can rapidly build up in one area Fungus of the Day Penicillin Poor conditions in lab fungus appears on petri dish with staph infection over the weekend the bacteria are suppressed even though it s not touching it It spits out chemicals to kill bacteria Most likely spits out enzymes to break down is to outcompete in their environment What is the role of the fungal cell wall then 1 Provide structure surrounding the hyphae 2 Gate of what goes out and what goes in 3 Compartmentalizes acts as a burrier between inner and outer 4 Must allow for growth 5 Protection against environment 6 Has to be able to sense its environment Detect if suitable mate grow towards light etc Intercalary Growth Adds to something already there Grass hair Radial Growth From the tip Inside material races towards the tip Fungal Cell Wall Composition Structural Components Chitin microfibrilis Gives it form and structure Chitosan in Zygomycota Gel Like Components Manoproteins Melanins Dark brown black pigments confer resistance to enzyme lysis confer mechanical strength and protect cells from UV light solar radiation and desiccation Why does the wall have so much protein just sitting there Proteins are what do things They do all the sensing and reacting and some even send signals back into the cell Do they digestion too not much structure Hyphal Growth 1892 Reinhar Tip is concentrated with microvesicles vesicle clouds and Spitzenkorper Spitzenkorper At the tip where all the stuff moves to Chitosomes At tip and responsible for making more chitin Chitanases and Glucanases are breaking down the tip while this happens Grows forward due to water pressure Septa Regular cross walls formed in Hyphae Hyphae with septa are Septate those without septa except to delimit reproductive structures and aging hyphae are called Aseptate or Coenoytic Primary Septa Formed as a process of hyphal extension and generally have a septal pore which allows for cytoplasmic and organelle movement Secondary Adventitious Septa Septa are imperforate formed to wall of Secretion Over 38K vesicles fuse with the hyphal tip What are they all doing Some break down tip some build up Some break down environment some spit out hormones etc Endoplasmic Retoriam ER Ruphiar Proteins are made Golgi distributes the proteins which go to the tip Nutrient Uptake Fungi move nutrients 1 000x against concentrating gradient Uses a lot of energy to do so uses pores and channels 1 3 of all the ATP energy a fungi creates goes into making a gradient so it can suck nutrients in It needs C N P S Mg Ca Fungus of the Day Hypomyces Lactifluroum Lobster Mushroom It is really a relationship between the mushroom and an ascomycete fungus Bright Orange is the ascomycete Causes the mushroom to contort and get hard People eat this Taste hot tangy shellfish taste Sources of Food Saprobes live on dead matter Mutualist Form symbiotic relationships Parasites on living organisms Predators Insect eaters Nematophagous Fungi Eat eggs capture with traps or nets even be an endoparasite Kill with mycotoxins digests directly destroy feeding sites in roots compete with worm for feeding tissues make worm avoid eating Traps Nematodes swells and constricts then releases enzymes to digest How do they know when there is a nematode Chemicals molecules from the exoskeleton trigger Appresoria Cell with a septa behind it that builds up pressure to force itself into underlying tissues Can generate up to 40X pressure in a car tire Uses hyrophobins to attach to the surface May use cuticle cell wall degrading enzymes as well Uses melanin to provided structures as not to pop Necessary for infection Formed by Ascomycetes Deuteromycetes and Oomycetes 2 Trigggers 1 Some parts of the wax of the plant cuticle have a chemical that it can detect 2 Detects the degree of hydrophobicity Knows if it is on rice high or tobacco low Latin for The Drinker Haustorium Made by fungi in several phyla Used to deliver effectors to cell as well as to adsorb nutrients Mainly a nutrient sink everything goes in doesn t give plant anything Keeps cell alive so it can feed Fungal hyphae breach cell wall but not cell membrane Spits out things to trick the plant so it wont attack it o Makes Appresoria once inside the plant Rhozoids Grass root like Small branching hyphae originating from the thallus Stronger and thicker than regular mycellia Anchor the fungus to the substrate like a root Release digestive enzymes to decomplose organic material Rhizomorphs Grass root like shape Actually a collecton of hyphae that lose individuality to form a complex interwoven tissue Typically reserve to the Basidiomycetes Have an organized and intricate structure of ring cortex and medulla Usually around wood