Pelomyxa palustris is a giant anaerobic/microaerobic amoeba, characterized by a number of exceptional cytological and physiological features, among them the presumed absence of energy producing organelles and the presence of endosymbiotic bacteria. These endosymbionts have been previously distinguished as: a large rectangular-shaped Gram-variable rod with a central cleft; a slender Gram-negative rod; and a slender Gram-positive rod. Using DNA extracted from P. palustris cysts, we have obtained three SSU rRNA gene sequences. We have determined that these sequences are affiliated to three different prokaryotic genera: Methanosaeta (a methanogenic archaea), Syntrophorhabdus (a syntrophic Gram-negative bacteria) and Rhodococcus (an aerobic chemoorganotrophic Gram-positive bacteria). To our knowledge, it is the first time that Syntrophorhabdus has been described as an endosymbiont in association with a methanogen. Strikingly, no traces of Methanobacterium formicicum could be detected, despite this methanogen had allegedly been isolated from trophozoites of P. palustris. It seems that the host and the endosymbionts have established a multipartite syntrophic consortium resembling to some extent those found in sewage treatment plants.
- MeSH
- Archamoebae microbiology physiology MeSH
- RNA, Archaeal genetics MeSH
- RNA, Bacterial genetics MeSH
- Deltaproteobacteria classification genetics isolation & purification physiology MeSH
- Phylogeny MeSH
- Methanosarcinales classification genetics isolation & purification physiology MeSH
- Rhodococcus classification genetics isolation & purification physiology MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Sequence Analysis, RNA MeSH
- Symbiosis * MeSH
- Publication type
- Journal Article MeSH
Strain CCM 4446T, with notable biodegradation capabilities, was investigated in this study in order to elucidate its taxonomic position. Chemotaxonomic analyses of quinones, polar lipids, mycolic acids, polyamines and the diamino acid of the cell-wall peptidoglycan corresponded with characteristics of the genus Rhodococcus. Phylogenetic analysis, based on the 16S rRNA gene sequence, assigned strain CCM 4446T to the genus Rhodococcus and placed it in the Rhodococcus erythropolis 16S rRNA gene clade. Further analysis of catA and gyrB gene sequences, automated ribotyping with EcoRI restriction endonuclease, whole-cell protein profiling, DNA-DNA hybridization and extensive biotyping enabled differentiation of strain CCM 4446T from all phylogenetically closely related species, i.e., Rhodococcus baikonurensis, Rhodococcus qingshengii, Rhodococcus erythropolis and Rhodococcus globerulus. The results obtained show that the strain investigated represents a novel species within the genus Rhodococcus, for which the name Rhodococcus degradans sp. nov., is proposed. The type strain is CCM 4446T ( = LMG 28633T).
- MeSH
- Genes, Bacterial MeSH
- DNA, Bacterial genetics MeSH
- Phospholipids chemistry MeSH
- Phylogeny * MeSH
- Nucleic Acid Hybridization MeSH
- Diaminopimelic Acid chemistry MeSH
- Mycolic Acids chemistry MeSH
- Fatty Acids chemistry MeSH
- Molecular Sequence Data MeSH
- Peptidoglycan chemistry MeSH
- Polyamines chemistry MeSH
- Soil Microbiology * MeSH
- Rhodococcus classification genetics isolation & purification MeSH
- Ribotyping MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Sequence Analysis, DNA MeSH
- Bacterial Typing Techniques MeSH
- Vitamin K 2 chemistry MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Switzerland MeSH
An agar-degrading bacterium, Rhodococcus sp. Q5, was isolated from printing and dyeing wastewater using a mineral salts agar plate containing agar as the sole carbon source. The bacterium grew from pH 4.0 to 9.0, from 15 to 35°C, and in NaCl concentrations of 0-5 %; optimal values were pH 6.0, 30°C, and 1 % NaCl. Maximal agarase production was observed at pH 6.0 and 30°C. The bacterium did not require NaCl for growth or agarase production. The agarase secreted by Q5 was inducible by agar and was repressed by all simple sugars tested except lactose. Strain Q5 could hydrolyze starch but not cellulose or carboxymethyl cellulose. Agarase activity could also be detected in the medium when lactose or starch was the sole source of carbon and energy. Strain Q5 could grow in nitrogen-free mineral media; an organic nitrogen source was more effective than inorganic carbon sources for growth and agarase production. Addition of more organic nitrogen (peptone) to the medium corresponded with reduced agarase activity.
- MeSH
- Agar metabolism MeSH
- Bacterial Proteins genetics metabolism MeSH
- Sodium Chloride metabolism MeSH
- Phylogeny MeSH
- Glycoside Hydrolases genetics metabolism MeSH
- Molecular Sequence Data MeSH
- Wastewater microbiology MeSH
- Industrial Waste analysis MeSH
- Rhodococcus classification genetics isolation & purification metabolism MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
We used reversed phase liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (RP-HPLC/MS-APCI) for direct analysis of triacylglycerols (TAGs) from four different cultivations of Rhodococcus erythropolis CCM 2595. This technique enabled us to identify and quantify the specific molecular species of TAGs directly from lipid extracts of the bacterium, including the determination of their basic characteristics such as retention time and mass spectra. A total of 17 TAGs having at least one odd-numbered-chain FA (fatty acid) were found. This is the first time when odd-chain TAGs, predominantly with pentadecanoic, margaric, and margaroleic acids, were identified. Multiple linear regression analyses were used for predicting retention times of molecular species, predominantly of odd-chain TAGs. Cultivations on two different substrates at two different temperatures (20 and 30 degrees C) showed that only temperature had any effect on the content of TAGs. In cultivations with succinate as a carbon source the content of these TAGs increased by half (i.e., from 23.5 to 34.2%) when the cultivation temperature was lowered from 30 to 20 degrees C. The content of the PoPoMo, PoMoO and PPoMo (see Table 1) TAGs containing the odd-numbered-chain margaroleic acid rose from 0.0 to 7.1% while in cultivation on phenol as a carbon source the lowering of cultivation temperature caused an increase of these TAGs from 0.5 to 6.7%.
A microtiter plate-based assay was developed for the automatic monitoring of degradation profile of the yellow-coloured nitrophenolic compounds. The method enables to reduce the intervals between measurements of substrate concentration to minutes and to overcome the problem of discontinuity of sampling typical for conventional methods. The concentrations of nitrophenolic compounds were calculated from the absorbance values determined automatically by BIOSCREEN C. Verification of the method was based on the comparison of results with the conventional HPLC method results. The values of the rate and saturation constants were comparable for both the microtiter plate-based assay and the conventional HPLC method. The automatic method described here seems to be efficient for the screening degradation studies, which requires the treatment of quantity of samples.
- MeSH
- Arthrobacter isolation & purification metabolism growth & development MeSH
- Bacteriological Techniques methods instrumentation MeSH
- Biodegradation, Environmental MeSH
- Financing, Organized MeSH
- Catechols metabolism MeSH
- Kinetics MeSH
- Culture Media MeSH
- Molecular Sequence Data MeSH
- Nitrophenols metabolism MeSH
- Soil Microbiology MeSH
- Rhodococcus genetics isolation & purification classification metabolism MeSH
- Sequence Analysis, DNA MeSH
- Chromatography, High Pressure Liquid MeSH
- Publication type
- Evaluation Study MeSH
Microorganisms were isolated from lignite freshly excavated in the Záhorie coal mine (southwestern Slovakia) under conditions excluding contamination with either soil or air-borne microorganisms. The isolates represented both Prokarya and Eukarya (fungi). All were able to grow on standard media, although some microorganisms were unstable and became extinct during storage of coal samples. Bacteria belonged to the genera Bacillus, Staphylococcus, and Rhodococcus, according to both morphological criteria and ITS sequences. Several bacterial isolates were resistant to antibiotics. The presence of anaerobic bacteria was also documented, although they have not yet been identified. Fungal isolates were typified by using their ITS sequences. They belonged to the genera Trichoderma (Hypocrea), Penicillium, Epicoccum, Metarhizium (Cordyceps), and Cladosporium. Several fungi produced compounds with antibiotic action against standard bacterial strains. The evidence for the presence of microorganisms in native lignite was obtained by means of fluorescence microscopy, scanning electron microscopy, and electron microprobe analysis. Results demonstrated that microorganisms were able to survive in the low-rank coal over a long time period.
- MeSH
- Bacteria, Anaerobic isolation & purification MeSH
- Anti-Bacterial Agents biosynthesis pharmacology MeSH
- Drug Resistance, Microbial MeSH
- Antibiosis MeSH
- Bacillus isolation & purification classification MeSH
- Bacteria isolation & purification classification MeSH
- DNA, Bacterial genetics chemistry MeSH
- Financing, Organized MeSH
- Microscopy, Fluorescence MeSH
- Mining MeSH
- DNA, Ribosomal Spacer genetics chemistry MeSH
- Electron Probe Microanalysis MeSH
- Microscopy, Electron, Scanning MeSH
- Mitosporic Fungi isolation & purification classification MeSH
- Molecular Sequence Data MeSH
- Rhodococcus isolation & purification classification MeSH
- DNA, Ribosomal genetics chemistry MeSH
- Sequence Analysis, DNA MeSH
- Staphylococcus isolation & purification classification MeSH
- Coal microbiology MeSH
- Geographicals
- Slovakia MeSH
The taxonomic position of a bacterial strain isolated from the femur of the remains of Jost Lucemburský, margrave in Moravia, Brno (Czech Republic), was investigated by phenotypic, chemotaxonomic and molecular taxonomic methods. The chemotaxonomic characteristics, including the cell-wall amino acid and sugar compositions, the quinone system and the fatty acid profile, were in good agreement with those of the genus Rhodococcus. The G+C content of the DNA was 67.4 mol%. Comparative 16S rRNA gene sequencing demonstrated that the unknown strain represents a distinct line of descent within the genus Rhodococcus. The nearest relatives of the bacterium were Rhodococcus opacus and Rhodococcus percolatus. The unknown bacterium was readily distinguished from these species by using phenotypic methods. On the basis of phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium be classified as Rhodococcus jostii sp. nov. The type strain is strain IFO 16295T (= CCM 4760T).
- MeSH
- Amino Acids analysis MeSH
- Benzoquinones analysis MeSH
- Cell Wall chemistry MeSH
- DNA, Bacterial genetics MeSH
- Phenotype MeSH
- Phylogeny MeSH
- Humans MeSH
- Fatty Acids analysis MeSH
- Molecular Sequence Data MeSH
- Paleontology MeSH
- Rhodococcus classification genetics isolation & purification MeSH
- RNA, Ribosomal, 16S chemistry MeSH
- Carbohydrates analysis MeSH
- Base Composition MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Comparative Study MeSH
- Geographicals
- Czech Republic MeSH
