Tetraploidy in a growth-retarded fetus with a thick placenta.
Explore the source record for details and available documents.
Abortion, Induced↗
Biomedical subjects
H Reichenbach
Publications and source records attributed to H Reichenbach.
Molecular evidence for association between the sphingobacterium-like organism "Candidatus comitans" and the myxobacterium Chondromyces crocatus.
Seven strains of the myxobacterium Chondromyces crocatus, isolated from widely separated geographic regions, were investigated for the presence of an associate gram-negative, rod-shaped companion bacterium that is phylogenetically related to the genus Sphingobacterium and has been named "Candidatus comitans" (C. A. Jacobi, E. Stackebrandt, H. Reichenbach, and B. J. Tindall, Int. J. Syst. Bacteriol. 46:119-122, 1996). Five of the Chondromyces strains were found to be associated with a companion bacterium, and one strain lost its companion during the study. A 16S ribosomal DNA (16S rDNA) clone library was generated for each Chondromyces culture. Sequence similarity was > 99.1% for all but one strain of C. crocatus and all but one strain of "Candidatus comitans". The three analyzed 16S rDNA clone sequences of the companion of Cm c7 indicated that this companion strain is slightly less related to the other companion strains. The association between the companion and the myxobacterium including the sporangioles was determined by in situ hybridization with fluorescently labeled rRNA probes and scanning confocal laser microscopy. Based on these results, there are indications that the companion strains may survive environmental stress by inclusion in the aggregates and in the sporangioles of the myxobacterium.
Bacteria↗
Further characterization and in situ localization of chain-like aggregates of the gliding bacteria Myxococcus fulvus and Myxococcus xanthus.
For the first time, chain-like aggregates, called "strands," have been enriched from crude cell wall preparations of liquid-grown vegetative cells of two strains of Myxococcus xanthus. These strands are highly isomorphic to macromolecular structures, previously described for Myxococcus fulvus (Lünsdorf and Reichenbach, J. Gen. Microbiol. 135:1633-1641, 1989). The strands are morphologically composed of ring elements, consisting of six or more peripheral protein masses and possibly three small central masses. The ring elements are linked by two parallel strings of filamentous proteins, called elongated elements, which keep the ring elements at a constant distance. The overall dimensions of the ring elements are 16.6 +/- 1.0 nm (n = 55) for M. xanthus Mx x48 and 16.4 +/- 1.5 nm (n = 37) for M. xanthus DK 1622. The distance between the ring elements, as a measure of the length of the elongated elements, is 16.6 +/- 1.1 nm (n = 59) for strain Mx x48 and 15.5 +/- 0.6 nm (n = 41) for strain DK 1622. Characteristically, the strands and oligomeric forms thereof show a strict association with the outer membrane. In situ studies of freeze-fractured cells of M. fulvus showed ring elements, isomorphic to those described for M. xanthus, within the periplasm; they appeared in parallel rows just below the outer membrane but not in direct contact with the cytoplasmic membrane. A three-dimensional model summarizes the morphological data. It is hypothesized that the chain-like strands, as building blocks of a more complex belt-like continuum, represent the peripheral part of the gliding machinery, which transforms membrane potential energy into mechanical work.
Bacterial Proteins↗
"Candidatus comitans," a bacterium living in coculture with Chondromyces crocatus (myxobacteria).
We describe the phylogenetic position and some taxonomically relevant characteristics of a small pleomorphic gram-negative bacterium that was cocultured with some strains of the myxobacterium Chondromyces crocatus that were isolated from the same geographic and ecological habitat. A 16S ribosomal DNA analysis revealed that the companion was a member of the "Cytophaga-Flavobacterium-Bacteroides" complex and was most closely related to members of the genus Sphingobacterium. The results of a fatty acid analysis, an isoprenoid composition analysis, and a DNA G+C content analysis and the presence of sphingolipids confirmed that this bacterium is affiliated with the genus Sphingobacterium. As the companion bacterium survived for only a few generations on solid media and could not be maintained in pure culture, we assign to this novel taxon that lives in close association with the myxobacterium C. crocatus Candidatus status as "Candidatus comitans."
Bacteroidetes↗
Epothilons A and B: antifungal and cytotoxic compounds from Sorangium cellulosum (Myxobacteria). Production, physico-chemical and biological properties.
An antifungal activity against Mucor hiemalis was detected in the culture broth of Sorangium cellulosum (Myxococcales) strain So ce90. The activity was excreted into the supernatant during the log and early stationary phase. When the adsorber resin XAD-16 was added to the culture, the active metabolites were quantitatively bound to the resin. The epothilons showed a high cytotoxicity for animal cells and mimic the biological effects of taxol (BOLLAG et al., Cancer Res. 55: 2325 approximately 2333, 1995).
Animals↗
The jerangolids: A family of new antifungal compounds from Sorangium cellulosum (Myxobacteria). Production, physico-chemical and biological properties of jerangolid A.
An antifungal activity was detected in the culture broth of the myxobacterium, Sorangium cellulosum strain So ce 307. The activity was excreted into the supernatant during the log and early stationary phase. When the organism was fermented in the presence of the adsorber resin XAD-16, the metabolite was quantitatively bound to the resin. The main component, jerangolid A, has structural similarities to ambruticin, which is also produced by strains of Sorangium cellulosum.
Antifungal Agents↗
Hereditary congenital posterior dislocation of radial heads.
We report on 4 patients with congenital posterior dislocation of radial heads in 3 generations of a family. Radiographs of the elbow joints of 3 individuals are presented. All affected subjects have mild limitation of extension and a strong restriction of rotation in the elbows. Comparison with previously described patients shows similarities in the X-ray findings. Congenital posterior dislocation of the radial head can be unilateral or bilateral. This malformation is also found in patients with antecubital pterygium or nail-patella syndrome. This family confirms the autosomal dominant inheritance of congenital posterior dislocation of radial heads.
Adolescent↗
Chondramides A approximately D, new antifungal and cytostatic depsipeptides from Chondromyces crocatus (myxobacteria). Production, physico-chemical and biological properties.
Novel depsipeptides, named chondramides were produced at levels up to 4.3 mg/liter by several myxobacteria of the genus Chondromyces. The compounds are structurally closely related to jaspamide/jasplakinolide from marine sponges of the genus Jaspis. Initially the chondramides were detected in acetone extracts of the biomass of Chondromyces crocatus, strain Cm c2. So far, four structural variants could be characterized, the chondramides A approximately D. They inhibited the growth of a few yeasts and showed high cytostatic activity against cultivated human and animal cells.
Animals↗
Gephyronic acid, a novel inhibitor of eukaryotic protein synthesis from Archangium gephyra (myxobacteria). Production, isolation, physico-chemical and biological properties, and mechanism of action.
A new antibiotic compound, gephyronic acid was isolated from the culture broth of the myxobacterium, Archangium gephyra strain Ar 3895. Up to 3 mg/liter was produced during the logarithmic and stationary growth phase. The compound is an aliphatic acid, which tends to form a hemiacetal. Both forms inhibited growth of yeasts and molds (MIC 1-25 micrograms/ml) and had a cytostatic effect on mammalian cell cultures (IC50 10-60 ng/ml). Gephyronic acid is a specific inhibitor of eukaryotic protein synthesis showing an IC50 of 1-2 x 10(-7) mol/liter in an in vitro translation assay.
Animals↗
The tartrolons, new boron-containing antibiotics from a myxobacterium, Sorangium cellulosum.
New antibiotics were isolated from the culture broth of the myxobacterium, Sorangium cellulosum, strain So ce 678. The antibiotics were active against Gram-positive bacteria and mammalian cells. They were named tartrolon A and B. Tartrolon B contains a boron atom. The boron binding region of tartrolon is identical with that of boromycin and aplasmomycin.
Anti-Bacterial Agents↗
Disorazol A, an efficient inhibitor of eukaryotic organisms isolated from myxobacteria.
A new antibiotic, disorazol, was isolated from the culture broth of the myxobacterium, Sorangium cellulosum strain So ce 12. It is a macrocyclic compound containing two oxazole rings. The antibiotic acted against many fungi and mammalian cell cultures. The latter responded to extremely low doses (MIC 3-30 pg/ml). None of the tested bacteria and yeasts were inhibited.
Animals↗
The ripostatins, novel inhibitors of eubacterial RNA polymerase isolated from myxobacteria.
A new antibiotic, ripostatin, was isolated from the culture supernatant of the myxobacterium, sorangium cellulosum strain So ce377. It is a macrocyclic lactone carbonic acid containing an unsubstituted phenyl ring in a side chain. The antibiotic acts especially on Staphylococcus aureus, but seems not to penetrate most bacteria. The MIC values are in the range of 1 microgram/ml. Ripostatin is an inhibitor of eubacterial RNA polymerase. It interferes with the initiation of RNA synthesis.
Anti-Bacterial Agents↗
Sorangiolid A, a new antibiotic isolated from the myxobacterium Sorangium cellulosum So ce 12.
Explore the source record for details and available documents.
Animals↗
Chivosazol A, a new inhibitor of eukaryotic organisms isolated from myxobacteria.
A new antibiotic, chivosazol, was isolated from the culture broth of the myxobacterium Sorangium cellulosum strain So ce12. It is a macrocyclic ring with one oxazol ring and a glycosidically bound 6-deoxyglucose (quinovose) at C-11. The antibiotic shows antimicrobial activity against yeasts and filamentous fungi, and is especially potent against mammalian cells. It was not active against bacteria.
Animals↗
Ratjadon: a new antifungal compound from Sorangium cellulosum (myxobacteria) production, physio-chemical and biological properties.
An antifungal activity, ratjadon, was detected in the culture broth of Sorangium cellulosum (Myxococcales) strain So ce360. The metabolite was quantitatively bound to the adsorber resin XAD-16, which was added to the medium at the beginning of the fermentation. The antibiotic spectrum was narrow, but some important phytopathogenic fungi, especially species of Oomycetes, were inhibited at very low concentrations.
Animals↗
Two binding sites of inhibitors in NADH: ubiquinone oxidoreductase (complex I). Relationship of one site with the ubiquinone-binding site of bacterial glucose:ubiquinone oxidoreductase.
The effect of ten naturally occurring and two synthetic inhibitors of NADH:ubiquinone oxidoreductase (complex I) of bovine heart, Neurospora crassa and Escherichia coli and glucose:ubiquinone oxidoreductase (glucose dehydrogenase) of Gluconobacter oxidans was investigated. These inhibitors could be divided into two classes with regard to their specificity and mode of action. Class I inhibitors, including the naturally occurring piericidin A, annonin VI, phenalamid A2, aurachins A and B, thiangazole and the synthetic fenpyroximate, inhibit complex I from all three species in a partially competitive manner and glucose dehydrogenase in a competitive manner, both with regard to ubiquinone. Class II inhibitors including the naturally occurring rotenone, phenoxan, aureothin and the synthetic benzimidazole inhibit complex I from all species in an non-competitive manner, but have no effect on the glucose dehydrogenase. Myxalamid PI could not be classified as above because it inhibits only the mitochondrial complex I and in a competitive manner. All inhibitors affect the electron-transfer step from the high-potential iron-sulphur cluster to ubiquinone. Class I inhibitors appear to act directly at the ubiquinone-catalytic site which is related in complex I and glucose dehydrogenase.
Acetobacteraceae↗
Identification of the yeast ACC1 gene product (acetyl-CoA carboxylase) as the target of the polyketide fungicide soraphen A.
Soraphen A, a polyketide isolated from the myxobacterium Sorangium cellulosum, is a potent inhibitor of fungal growth. We have used a genetic approach to localize the target of this drug, employing Saccharomyces cerevisiae as a model organism. we have isolated soraphen A-resistant mutants and found that all of them map at the same genetic locus and exhibit a broad range of semidominant phenotypes. Data from genetic crosses of soraphen A-resistant clones with an acc1 mutant revealed that ACC1, coding for acetyl-CoA carboxylase (E.C. 6.4.1.2), is tightly linked to soraphen A resistance. Partially-purified enzyme extracts containing acetyl-CoA carboxylase were prepared and assayed for their soraphen A sensitivity. Our experiments showed that the catalytic activity of the wild-type enzyme is inhibited in vitro by soraphen A while the mutant enzyme remains catalytically active. Taken together these data strongly suggest that the ACC1 gene product is the primary target for soraphen A in vivo.
Acetyl-CoA Carboxylase↗
Two binding sites for naturally occurring inhibitors in mitochondrial and bacterial NADH:ubiquinone oxidoreductase (complex I).
Explore the source record for details and available documents.
Animals↗