Myxomycetes

Ishibashi, M. Iwasaki, T. Imai, S. Sakamoto, S. Yamaguchi, K. Ito, A. (2001) Laboratory culture of the Myxomycetes formation of fruitmg bodies of Didymium bahiense and its plasmodial production of makaluvamine A. J. Nat. Prod., 64, 108-10. 

Plasmodial slime molds (Myxomycetes) are eukaryotic bacteriovores usually occurring in terrestrial ecosystems. Although a few species appear to be confined to the tropics or subtropics, the majority are cosmopolitan and approximately 1000 species have been recognised. In the assimilative... 

Such attack can always be detected afterwards by a mottled or pitted appearance of the cell walls. Also, I do not think that Myxomycetes, the slime molds, were important primary agents in the biochemical stages of coal formation because their preferred habitat is, for example, rotting tree stumps rather than a peaty mass. 

CapILLITIUM An assemblage of simple threads or a network of fine branched strands found mixed with the spores in the sporangia of many Myxomycetes and within the fruit body of some gasteromycetes. 

Slime- Mold-like Resembling a Myxomycete plasmodium. 

Myxamoeba A uninucleate, naked, or individual myxomycete which lacks flagella or cilia but creeps like an Amoeba. 

The fungi include Slime molds (Myxomycetes) algal fungi (Phy-comycetesy, sac fungi (Ascomycetes), and club fungi Basidiomycetes) among others. The yeasts and most of the molds with which food products are associated in some way are of the Ascomycetes variety. 

Dembitsky VM, Rezanka T, Spizek J, Hanus LO (2005) Secondary Metabolites of Slime Molds (Myxomycetes). Phytochemistry 66 747... 

ABSTRACT The Myxomycetes (true slime molds) are an unusual group of primitive organisms that may be assigned to one of the lowest classes of eukaryotes. As their fruit bodies are very small and it is very difficult to collect much quantity of slime molds, few studies have been made on the chemistry of myxomycetes. Cultivation of the plasmodium of myxomycetes in a practical scale for natural products chemistry studies is known only for very limited species such as Physarum polyeephalum. We recently studied the laboratory-cultivation of myxomycetes and several species have been successfully cultured in agar plates. Chemical constituents of cultured plasmodia of several species of myxomycetes of the genera Didymium and Physarum were examined to obtain several sterols, new lipid, or pyrroloiminoquinone derivatives. Previous studies on the chemistry of the secondary metabolites of myxomycetes by other groups are also described here. 

Natural Products continue to provide a great structural diversity and offer major opportunities for finding novel low-molecular-weight lead compounds. No more than 10% of the earth s biodiversity has been examined for biological activity tests [1]. How to access this unexplored natural diversity is quite an important problem. Among the many unexplored organisms, here we focus on Myxomycetes . 

The Myxomycetes (true slime molds) are an unusual group of primitive organisms that may be assigned to one of the lowest classes of eukaryote [2]. In the assimilative phase of their life cycle (Figure 1)... 

Steglich [3] and Asakawa s group [4] have isolated several types of metabolites from field-collected samples of several myxomycete species. Cultivation of the plasmodium of myxomycetes in a considerable scale to cany out chemical studies is known only for... 

Fruit bodies of wild myxomycetes often have bright colors. In 1980 Steglich et al. isolated red and yellow pigments from methanol extracts of 2 g of the red fruit bodies of Arcyria denudata [7], Structure of these pigments were elucidated by spectral data as a series of bisindole maleimides, and they were named arcyriarubin B (1), C (2), arcyriaflavin B (3), C (4), and arcyrioxepin A (5). 1, 2, and 5 were red... 

Recently considerable attention has been focused on the metabolites belonging to bisindolylmaleimides such as staurosporine (28) [12], UCN-01 (29) [13], rebeccamycin (30) [14], which were produced by the family of Streptomyces, Actinomycetes, and Saccharothrixes. These metabolites cause topoisomerase I mediated DNA cleavage, potent inhibition of protein kinase C and cell-cycle-regulating cyclin-dependent kinase (CDK), and cell-cycle checkpoint inhibition [15]. It seems interesting that myxomycetes also contain the bisindole metabolites having related structures to 28 - 30. 

From the myxomycete of the same genus, Metatrichia vesparium, vesparione (40), a naphtha[2,3-b]pyrandione derivative was isolated as a red pigment of its fruit bodies, and this compound exhibited antibiotic properties [21]. 

Rezanka analysed the fatty acid composition of several species of myxomycetes. In addition to the common fatty acids, polyunsaturated and methylene non-interrupted polyunsaturated fatty acids, for example, with 5, 9- and/or 5, 11-double bonds, were identified by GS-mass spectrometry of their corresponding oxazolines [25]. Multibranched polyunsaturated fatty acid and its four glycosides (50 -54) were isolated from seven different myxomycetes [26]. The absolute configurations of hydroxyl groups were determined by modified Mosher s method, and the glycosides were revealed to contain glucose, mannose, and rhamnose. It may be interesting that these fatty acid constituents contained by the seven species of myxomycetes were different (Table 1). 

Table 1. Distribution of the fatty acid derivatives identified in the seven species of myxomycetes...

Compounds described above are all those isolated from wild myxomycetes in the stage of fruit bodies in their lifecycle. In the lifecycle of myxomycetes (Figure 1), there is a stage of plasmodium before that of fruit body. A few studies of chemical constituents of plasmodial stages of myxomycetes have been described. 

From plasmodia of another common myxomycetes Ceratiomyxa fruticulosa, five 6-alkyl-4-methoxypyran-2-ones, ceratiopyron A (60) D (63), and ceratioflavin A (64) were isolated [29]. Their structures were determined by spectroscopic and chemical investigations, and five compounds possessed side chains with varying... 

Cultivation of the plasmodium of myxomycetes in a practical scale has been known only for very limited species. Physarum polycephalum may be the most familiar species of myxomycetes because of the ease with which its plasmodium may be grown in the laboratory. It has been therefore used extensively in physiological, biochemical, and genetic studies as well as in schools for model organisms. Mass culture of the plasmodia of Physarum polycephalum... 

Murakami-Murofushi et al. further studied the lipid fraction of this myxomycete and succeeded in isolating novel lysophosphatidic acid (PHYLPA) (73) [39]. This compound, composed of cyclic phosphate and cyclopropane-containing hexadecanoic acid, inhibited more than... 

The explorative studies of myxomycetes chemistry described above demonstrated that myxomycetes developed a rather unique secondary metabolism which offers a wide field of further studies. Only a few of more than 500 known species have been investigated so far. Therefore, Steglich described that for further progress the... 

The fruit bodies of the myxomycetes Didymium bahiense var. bahiense (Order Physarales Family Didymiaceae) were collected at Ina, Nagano Prefecture, Japan, in August, 1999. The spores contained in the fruit bodies were applied on an agar plate (lactose 0.1%, peptone... 

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