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Theory in Biosciences = Theorie in Den... May 2019Detailed analyses into the life cycle of the soil-dwelling microbe Dictyostelium discoideum led to the conclusion that this "social amoeba" practices some form of...
Detailed analyses into the life cycle of the soil-dwelling microbe Dictyostelium discoideum led to the conclusion that this "social amoeba" practices some form of "non-monoculture farming" via the transfer of bacteria to novel environments. Herein, we show that in myxomycetes (plasmodial slime molds or myxogastrids) a similar "farming symbiosis" has evolved. Based on laboratory studies of two representative species in the genera Fuligo and Didymium, the sexual life cycle of these enigmatic microbes that feed on bacteria was reconstructed, with reference to plasmo- and karyogamy. We document that the spores carry and transfer bacteria and hence may inoculate new habitats. The significance of this finding with respect to Ernst Haeckel's work on myxomycetes and his concept of ecology are addressed.
Topics: Bacteria; Biological Evolution; Ecology; Microscopy, Electron, Scanning; Models, Biological; Myxomycetes; Phylogeny; Symbiosis
PubMed: 30809766
DOI: 10.1007/s12064-019-00285-3 -
The Journal of Eukaryotic Microbiology Sep 2019Myxomycetes (plasmodial slime molds) are abundant protist predators that feed on bacteria and other microorganisms, thereby playing important roles in terrestrial...
Myxomycetes (plasmodial slime molds) are abundant protist predators that feed on bacteria and other microorganisms, thereby playing important roles in terrestrial nutrient cycling. Despite their significance, little is known about myxomycete communities and the extent to which they are affected by nutrient availability. We studied the influence of long-term addition of N, P, and K on the myxomycete community in a lowland forest in the Republic of Panama. In a previous study, microbial biomass increased with P but not N or K addition at this site. We hypothesized that myxomycetes would increase in abundance in response to P but that they would not respond to the sole addition of N or K. Moist chamber cultures of leaf litter and small woody debris were used to quantify myxomycete abundance. We generated the largest myxomycete dataset (3,381 records) for any single locality in the tropics comprised by 91 morphospecies. In line with our hypothesis, myxomycete abundance increased in response to P addition but did not respond to N or K. Community composition was unaffected by nutrient treatments. This work represents one of very few large-scale and long-term field studies to include a heterotrophic protist highlighting the feasibility and value in doing so.
Topics: Ecosystem; Forests; Myxomycetes; Nitrogen; Nutrients; Panama; Phosphorus; Plant Leaves; Potassium; Soil; Wood
PubMed: 30793409
DOI: 10.1111/jeu.12724 -
Annals of the New York Academy of... Oct 1953
Topics: Fungi; Humans; Myxomycetes
PubMed: 13139285
DOI: 10.1111/j.1749-6632.1953.tb30273.x -
Mycologia 2015Based on a combination of morphological and molecular investigations, a critical revision of the widely distributed myxomycete Tubifera ferruginosa is presented. A...
Based on a combination of morphological and molecular investigations, a critical revision of the widely distributed myxomycete Tubifera ferruginosa is presented. A phylogeny of the morphospecies, based on partial 18S nuc rDNA sequences, displays several clearly distinct clades, all differing by a genetic distance (p distance) of at least 0.15, with the distance within the clades below 0.11. These molecular differences correlate with morphological characters, such as the shape of sporothecal tips, the color of immature fructifications and the ultrastructure of the inner surface of the peridium. The combination of morphological and molecular data provides evidence that T. ferruginosa is actually a species complex, representing at least seven species. These are T. ferruginosa sensu stricto, T. applanata, T. corymbosa, T. dudkae, T. magna, T. montana and T. pseudomicrosperma. Among these T. applanata and T. dudkae (as Reticularia dudkae) were described recently based on morphological characters and the 18S nuc rDNA phylogeny confirmed their separation. Another four species, T. corymbosa, T. magna, T. montana and T. pseudomicrosperma, are described here. We propose an epitype for T. ferruginosa sensu stricto and recognize subsp. ferruginosa and subsp. acutissima within this species. All studied taxa of the T. ferruginosa complex are shown to lack a capillitium. Structures formerly described as capillitium represent the hyphae of fungi occurring within the fructifications.
Topics: DNA, Fungal; Genetic Variation; Myxomycetes; Phylogeny; Species Specificity
PubMed: 26240306
DOI: 10.3852/14-271 -
Optics Express Jul 2010In this paper we report evidence of structural color in Myxomycetes, a group of eukaryotic microorganisms with an uncertain taxonomic position. We investigated the...
In this paper we report evidence of structural color in Myxomycetes, a group of eukaryotic microorganisms with an uncertain taxonomic position. We investigated the Diachea leucopoda, which belongs to the Physarales order, Myxomycetes class, and found that its peridium -protective layer that encloses the mass of spores- is basically a corrugated layer of a transparent material, which produces a multicolored pointillistic effect, characteristic of this species. Scanning (SEM) and transmission (TEM) electron microscopy techniques have been employed to characterize the samples. A simple optical model of a planar slab is proposed to calculate the reflectance. The chromaticity coordinates are obtained, and the results confirm that the color observed is a result of an interference effect.
Topics: Models, Biological; Myxomycetes; Pigmentation
PubMed: 20720990
DOI: 10.1364/OE.18.016055 -
Proceedings of the National Academy of... Dec 1973A procedure for screening several thousand clones for alterations in a specific gene product was apapplied to mutagenized cultures of Dictyostelium discoideum. Six...
A procedure for screening several thousand clones for alterations in a specific gene product was apapplied to mutagenized cultures of Dictyostelium discoideum. Six strains were recovered which had less N-acetylglucosaminidase (EC 3.2.1.30) than the wild type. In addition, we isolated four strains in which the enzyme was temperature-sensitive. The enzyme from one of these strains had an altered substrate affinity.N-Acetylglucosaminidase is present at a low level in cells grown on bacteria and increases up to 10-fold during the aggregation stage of development. The enzyme appears to be essential to maintain migrating pseudoplasmodia of normal size, as shown by the fact that all of the mutant strains which accumulate very little N-acetyl-glucosaminidase formed only small migrating pseudoplasmodia containing less than 10% the number of cells found in the wild-type pseudoplasmodia. The small pseudoplasmodia migrated at less than a third the rate of wild-type pseudoplasmodia and ultimately formed diminutive fruiting bodies. N-Acetylglucosaminidase thus appears to be a developmental enzyme that functions during the migration stage.
Topics: Acetamides; Clone Cells; Genes; Hexosaminidases; Lysosomes; Mutation; Myxomycetes; Temperature
PubMed: 4519628
DOI: 10.1073/pnas.70.12.3356 -
Mycologia 1973
Topics: Arthrobacter; Culture Media; Enterobacter; Escherichia coli; Myxomycetes; Spores, Fungal
PubMed: 4589741
DOI: No ID Found -
Advances in Biophysics 1973
Topics: Actins; Adenosine Triphosphate; Fungal Proteins; Myosins; Myxomycetes; Plasmodium; Tropomyosin
PubMed: 4800161
DOI: No ID Found -
Advances in Microbial Physiology 1971
Review
Topics: Aspergillus; Carbohydrate Metabolism; Cell Adhesion; Cell Aggregation; Cell Differentiation; Cell Wall; Chemotaxis; Enzymes; Fungi; Light; Morphogenesis; Myxomycetes; Neurospora; Plant Growth Regulators; Polymorphism, Genetic; Species Specificity; Spores, Fungal
PubMed: 4950260
DOI: 10.1016/s0065-2911(08)60405-1 -
Chromosoma 1972
Topics: Cell Nucleolus; Cell Nucleus; Chromosomes; Microscopy, Electron; Microtubules; Mitosis; Myxomycetes
PubMed: 5064173
DOI: 10.1007/BF00329562