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At least 19 recordsLinked to original sources
PubMed1979

[Aquatic myxobacteria as indicators in the evaluation of drinking water quality (author's transl))].

Aquatic myxobacteria were shown to be good indicators of surface contamination of drinking water, or water filtered by an inadequate soil profile, both in experiments with sterilized or biologically active soil profiles, resp., and in actual comparison data obtained in practical drinking water analyses. In experimental investigations with artificial profiles, aquatic myxobacteria were retained to a considerably greater degree than E. coli or P. fluorescens due to stronger forces of adhesion. In a number of bacteriological drinking water analyses, this property was confirmed insofar as aquatic myxobacteria could regularly be demonstrated when inspecting hygienically deficient wells or springs. The confirmed presence of E. coli, on the other hand, showed a considerably lesser correlation with the results of on the spot evaluations of hygienic conditions. It must be urgently advised to include the search for aquatic myxobacteria in bacteriological drinking water analyses, since, contrary to the demonstration of E. coli, not only the actual but, in addition, the potential hazard of contamination of drinking water with bacteria present in superficial soil strata is indicated.

Bacteriological Techniques↗
PubMed1979

[Aquatic myxobacteria (Sporocytophaga cauliformis) and the order "Myxobacterales" (author's transl)].

The indicator function of aquatic myxobacteria for the purpose of evaluating drinking water quality as well as their occurrence in sewage effluent make it desirable to describe these hitherto little known organisms in more detail. To this end, a comparative investigation of anaerobic myxobacteria of the genus Sphaerocytophaga, two typical representatives of the Order Myxobacterales (Myxococcus fulvus, Sporocytophage cauliformis), and a strain ov Vitrepscilla (Vitroescilla proteolytica) was undertaken. With respect to culture morphology, the migratory fringe surrounding colonies of Sphaerocytophaga similar to the other strains studies was a prominent characteristic. In particular, the similarity with colonies of Sporocytophaga cauliformis was apparent. The gliding motility typical of Sphaerocytophaga could be demonstrated in all of the strains investigated. Scanning electron micrographs revealed an amorphous layer of slime covering the cell surfaces in all strains compared in this study, thus excluding the existence of more rigid organelles of locomotion. Taxonomically, the anaerobec myxobacteria of the oral cavity (Sphaerocytophaga) belong to the Order "Myxobacterales" and not the "Eubacterales", i.e., to the genus Fusobacterium. This is clearly suggested by their motility lacking flagella and, above all, by their cell morphology which differs from the Eubacterales.

Culture Media↗
PubMed1979

[Occurrence and distribution of fruiting body-forming myxobacteria in Siebengebirge. Comparative studies with special reference to characteristic biotypes].

In the region of the "Siebengebirge" near Bonn, six characteristic biotopes were studied with respect to the occurrence of fruiting body forming myxobacteria. 23 different species, belonging to the 8 known genera, were found. The number of species in the respective biotopes varied between 6 and 17, the average numbers of species per sampling area were between 2.1 and 10.0. 15 species were found on dung pellets of wild living herbivorous mammals. Deciduous forest soils contained 13 species in spring, 17 species in autumn. Rock coverings contained 14, creek slopes 16, bark of living trees 9, and rotting wood 16 fruiting myxobacterial species. Myxococcus fulvus, Myxococcus coralloides and Archangium gephyra occurred in all biotops studied. The rare species were Melittangium boletus, Polyangium vitellinum, Stigmatella aurantiaca, and Chondramyces apiculatus. The composition of the myxobacterial flora depends on ecological factors (kind of dung pellets, rock, bark and pH). The ecological influences upon the distribution are discussed.

Altitude↗
PubMed1978

Comparison of spontaneous, UV-induced, and nitrosoguanidine-induced mutability to drug resistance in myxobacteria.

The UV survival curves of different strains of myxobacteria exhibited shoulders; in the case of Polyangium luteum, an unusual double shoulder appeared. Repair inhibitors like acriflavine, caffeine, and coumarin reduced the survival of UV-irradiated cells if the drugs were incorporated in the post-irradiation plating medium. The shoulders were reduced, but the final inactivation slopes were not affected by the repair inhibitors. Those strains that were resistant to UV were also more resistant to being killed by nitrosoguanidine. A variety of drug-resistant mutants occurred. The spontaneous mutation frequencies to drug resistance varied with the drug and the strain used. Drug-resistant mutants were inducible by UV irradiation and nitrosoguanidine. The UV mutability of Myxococcus xanthus was high compared to Cystobacter sp. However, the nitrosoguanidine mutability of M. xanthus was low compared to the other strains.

Acriflavine↗
PubMed1977

Isolation of sporopollenin from four myxobacteria.

Sporopollenin, a resistance material previously found only in algae, fungi, pollen grains, and in some plant spores, has been found in four species of Myxococcus. Sporopollenin was isolated from vegetative cells and myxospores of the myxobacteria tested but it was not detected in any of the other bacteria tested.

Bacteria↗
PubMed1977

A quantitative assay to study cell movement in the myxobacteria.

A simple quantitative assay has been developed to test the rate of cell movement of myxobacteria. The assay employs an agar surface and at no time are the cells cultured in a liquid environment. Isolation of a rate-increasing substance(s) from fruiting Myxococcus xanthus is reported. The understanding of the aggregative process in these bacteria will be aided by characterization of the chemotactic system.

Agar↗
PubMed1978

[On the distribution of myxobacteria in the temperate South America (author's transl)].

60 soil samples from Southern Chile, mainly from forests and grassland, yielded six species of myxobacteria. In forest soils Myxococcus coralloides and Myxococcus fulvus occur frequently, in grassland soils Myxococcus coralloides and Archangium gephyra are predominating. Myxococcus virescens, Melittangium lichenicola, and Cytobacter fuscus have been observed rarely. It is pointed out that due to climate factors a high soil acidity causes the low nuber of myxobacter species. A comparison with the number of species in substrates from important plant formations over various climates is given.

Chile↗
PubMed1975

[Myxobacteria of the Myxococcus family as indirect indicators of fecal matter in surface water. 1. Communication (author's transl)].

The fruiting-body-forming Myxobacteria of the Myxococcus order are coprophilic, i.e., they accumulate in biotopes that contain faecal substances. Therefore, a special detection of Myxococcus in water, based on the membrane-filter method, has been worked-out. Field studies, undertaken in the region of a mechanico-biological clarifying plant, above a certain stretch of a stream (the Regnitz) laden with waste-water, and on the Bodensee (=Lake Constance) have revealed a clear correlation between the load of faecal substances in such waters and their content of Myxococci. In this way, then, these germs can be used as indirect bacterial indicators of faecal substances.

Agar↗
PubMed1977

Bacteriolytic myxobacteria: parasites or scavengers?

The activity range of an enzymatic preparation from Myxococcus xanthus was assayed against some soil and rhizospheric bacteria. The lysis of unequally aged sensitive eubacterial populations, as related to their viability, was investigated and, at last, the often used streak method was checked and the relationship between cell viability and susceptibility to lysis is discussed.

Bacteriolysis↗
PubMed1975

Scanning electron microscopy of fruiting body formation by myxobacteria.

Scanning electron microscopy was used to follow fruiting body formation by pure cultures of Chondromyces crocatus M38 and Stigmatella aurantica. Vegetative cells were grown on SP agar and then transferred to Bonner salts agar for fructification. Fruiting in both species commences with the formation of aggregation centers which resemble a fried egg in appearance. In Chondromyces the elevated center or "yolk" region of the aggregation enlarges into a bulbous structure under which the stalk forms and lengthens. At maximum stalk height the bulb extends laterally as bud-like swellings appear. These are immature sporangia and are arranged in a distintive radial pattern around the top of the stalk. This symmetry is lost as more sporangia are formed. Stigmatella does not form a bulb; rather the yolk region of the aggregation center projects upward to form a column-like stalk which is nearly uniform in diameter throughout its length. At maximum stalk height, the terminus of the stalk develops an irregular pattern of bud-like swellings. These differentiate into sporangia. Stalks of 2-week-old mature fruiting bodies of both species appear to be cellular in composition. Stereomicrographs suggest orientation of these cells parallel to the long axis of the stalk. Stalks of 8-week-old fruiting bodies of Chondromyces were acellular and consisted of empty tubules, suggesting that the cells undergo degeneration with aging of the fruiting body.

Microscopy, Electron, Scanning↗
PubMed2026

Aggregicoccus is a myxobacterial genus inherently deficient in fruiting genes.

Myxobacteria are fascinating and important prokaryotes with remarkable multicellular behaviors, which make them a model system for studying prokaryotic development and cooperation. Although there have been sporadic discoveries of myxobacterial species unable to fruit, it is unclear whether the non-fruiting characteristic is due to taxon-specific genetic deficiency or suboptimal cultivation conditions. Aggregicoccus is a non-fruiting myxobacterial genus typified by a single validly published species, Ag. edonensis. In this study, we report five novel Aggregicoccus strains, which are classified into three novel type species, Ag. lacus, Ag. agri, and Ag. guangxiensis, based on polyphasic taxonomic analysis. All the Aggregicoccus strains are unable to produce fruiting bodies, but can still sporulate. We compared the genome differences between Aggregicoccus and Myxococcus; both genera belong to the Myxococcaceae family, and all the genomes are of similar sizes. The results showed that the Aggregicoccus strains are inherently deficient in the fruiting body-associated genomic information (FAGI). We propose an assessment of FAGI for the classification of non-fruiting myxobacterial species.IMPORTANCEFruiting body formation is traditionally regarded as a defining trait of myxobacteria. Here, we report that Aggregicoccus spp., including six strains of four species, can sporulate but are deficient in the fruiting body-associated genomic information (FAGI). This demonstrates that the non-fruiting characteristic in Aggregicoccus stems from inherent genetic deficiencies rather than suboptimal cultivation. Our findings highlight the need to assess FAGI presence in classifying non-fruiting lineages, innovate the isolation method, and refine our understanding of the diversity and evolution of the myxobacteria.

Aggregicoccus↗