slime molds slime molds…whatever darrin rubino hanover college biology department
TRANSCRIPT
Slime Molds
Slime Molds…WhateverDarrin Rubino
Hanover College Biology Department
Overview• What they are• What makes them unique• Life History and Ecology• Research• Conclusions
Slime Molds• Unfortunate name• Four different types of organisms• Protists (more or less)• Amoebozoa (kingdom)• Phylum Myxomycota– Myxomycetes (Class)– True slime molds– Acellular slime molds– Plasmodial slime molds
• Biological jewels
Slime Molds
• So bizarre, long misclassified• Long thought to be a fungi– myxa– mycetes
• Phylogenetic placement– Molecular– Developmental
• Own kingdom• Must understand life cycle to appreciate
Life cycle• Very unique• “Extravagant” life history• Does reproduce sexually (earliest protists)• Variable among species• General– Plasmogamy - join protoplasts– Karyogamy – fusion of nuclei– Meiosis
• Ploidy of structure
Plasmodium
• Incredible stage of lifecycle• Acellular – multinucleate (millions)– Synchronous– 8 – 10 hours
• Fluid and gelatinous • Streaming 1.35 mm/s• http://www.youtube.com/watch?v=UKSGAHAfWis
Plasmodium
• Phagotrophs– Bacteria– Yeast– Fungal spores– Decaying matter
• Expand while favorable conditions
• Declining conditions• http://
www.youtube.com/watch?v=p6OoHctERPs
Classification• Approximately 888
different species • Much variation• Class: Myxomycetes• Three subclasses• Six orders
Sporophore developmentSporophore typeSpore productionSpore colorCapillitiaCalcium or lime
1 mm
1 mm
Chocolate tube slimeStemonitis fusca
Yellow-fuzz cone slimeHemitrichia clavata
1 mm
Red raspberry slimeTubifera ferruginosa
Multigoblet slimeMetatrichia vesparium
1 mm
Life History and Ecology• Are these things common?• Did I ever even see one?• Very common in temperate forests
caca de luna
Enteridium lycoperdon
Life History and Ecology
• “…superficial and largely qualitative” (Ing)• Cosmopolitan• Requirements– Moisture– Temperature– Substrate– pH
Life History and Ecology
• Specialists – Assemblages – Bark
• Seasonal – Spring through October– October is peak
• Much more to be learned
Research Avenues
• Moist chamber technique• Physarum polycephalum
Current Research
• Synchronization of cell division• Senescence• Cancer
• Purified Poly(b-L-malic Acid)• Polycefin (polycephalum)• Deliver antisense gene silencing
therapies
CytologyGeneticsMolecular biologyBiochemistryBiophysicsMitosisMorphogenesisReproduction (cue)PhysiologyAging
Current Research
• Heavy metal clean up– Dog barf slime– Potential plant GMO
• Space – gravity sensing• Novel biological compounds– Trials necessary– Not just novelties (Keller)
Conclusions
• Unique protists• Few specialists (disease & economic impact)• Still much to learn– Application health/environment– Ecology
• Questions