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Carla C. C. R. De Carvalho - One of the best experts on this subject based on the ideXlab platform.
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Phenotypic Adaptations Help Rhodococcus erythropolis Cells during the Degradation of Paraffin Wax.
Biotechnology Journal, 2019Co-Authors: Carlos J. C. Rodrigues, Carla C. C. R. De CarvalhoAbstract:During crude oil extraction, the reduction in temperature and pressure results in the precipitation of paraffin wax that contains 20-40 carbon chain hydrocarbons. The paraffin wax may accumulate inside production tubes, pipelines, and processing facilities, and also in tankers during petroleum transportation. There are few bacterial strains that are able to degrade solid substrates. In the present study, the biodegradation of paraffin is evaluated using Rhodococcus erythropolis cells. This bacterium is able to grow using paraffin wax from an oil refinery plant as the sole carbon source. The cells grow as a thick biofilm over the solid substrate, make scale-like structures that increase the area of the initially smooth surface of paraffin, produce biosurfactants, and become more negatively charged than ethanol- or glucose-grown cells. When paraffin wax is supplied as microparticles, to increase the cell-substrate contact area and to simulate paraffin precipitation, the cells also adjust the composition of the fatty acids of the phospholipids of the cellular membrane to decrease its fluidity and paraffin biodegradation increases considerably. The study suggests that the phenotypic adaptation of R. erythropolis cells may be used to degrade paraffin wax under real conditions.
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rapid adaptation of Rhodococcus erythropolis cells to salt stress by synthesizing polyunsaturated fatty acids
Applied Microbiology and Biotechnology, 2014Co-Authors: Carla C. C. R. De Carvalho, Marco P C Marques, Nancy Hachicho, Hermann J HeipieperAbstract:Bacterial cells are known to adapt to challenging environmental conditions such as osmotic stress. However, most of the work done in this field describes the adaptation of growing populations where the new generations acquire traits that improve their ability to survive. In the present study, the responses of Rhodococcus erythropolis cells within the first 30 min after exposure to osmotic stress caused by sodium chloride were studied. The cells changed the total lipid fatty acid composition and also the net surface charge in the 30 min following exposure. Surprisingly, the cells produced a high percentage of polyunsaturated fatty acids. In the presence of 7.5 % NaCl, these polyunsaturated fatty acids, mainly eicosapentaenoic acid (C20:5ω3), arachidonic acid (C20:4ω6) and docosapentaenoic acid (C22:5ω3), comprise more than 36 % of the total fatty acids. The possible function of these very uncommon fatty acids in bacteria could be the decrease in the number of negatively charged groups in ion channels resulting in a repellence of the NaCl.
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adaptation of Rhodococcus erythropolis cells for growth and bioremediation under extreme conditions
Research in Microbiology, 2012Co-Authors: Carla C. C. R. De CarvalhoAbstract:Abstract Bioremediation of contaminated sites is rarely performed in nature under ideal growth conditions for bacteria. Extremophiles can grow at extreme values of temperature, pH, ionic strength and metal concentrations, but it may be difficult to find and isolate those possessing the required metabolic activities. In the present work, Rhodococcus erythropolis, a bacterium known to possess a large number of catabolic activities, was adapted to grow at 4–37 °C, pH 3–11 and in the presence of up to 7.5% sodium chloride and 1% copper sulfate. The large majority of adapted cells were able to maintain polarization of the membrane under the most difficult conditions tested and to adjust the net surface charge. The cells changed the composition of fatty acids of the cellular membrane according to conditions endured. Changes in the relative proportion of straight, methyl and cyclopropyl saturated, unsaturated and hydroxyl substituted fatty acids were observed, as well as production of polyunsaturated fatty acids unusual in bacteria. The adapted R. erythropolis cells were able to degrade C6–C16 n-alkanes and alcohols under the previously considered extreme conditions for this bacterium.
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adaptation of Rhodococcus erythropolis cells to high concentrations of toluene
Applied Microbiology and Biotechnology, 2007Co-Authors: Carla C. C. R. De Carvalho, Vanessa Fatal, S S Alves, Manuela M R Da FonsecaAbstract:Cells of Rhodococcus erythropolis DCL14 were adapted to increasing toluene concentrations in a mechanically stirred reactor. When the initial non-adapted cells were placed in contact with toluene, only 10.5% of cells remained viable after 1 h in the presence of 20% (v/v) toluene, while 8.6% of cells were viable after 28 h in the presence of an organic phase containing 80% (v/v) toluene in n-dodecane. Cell adaptation was studied by following the toluene consumption rate, the viability of the cell population, and the composition of the bacteria cellular membrane in the presence of increasing concentrations of toluene in the reactor. A maximum toluene concentration of 4.9 M, which corresponds to 52.4% (v/v) toluene in the organic phase, was achieved, toluene being consumed at 10.7 mg/(h mg protein). The adapted cells showed a substantially increased resistance to 50% ethanol and to concentrations of Betadine® and Micropur® tablets currently used in water purification, when compared to non-adapted cells.
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The remarkable Rhodococcus erythropolis
Applied Microbiology and Biotechnology, 2005Co-Authors: Carla C. C. R. De Carvalho, M. Manuela R. FonsecaAbstract:Rhodococcus erythropolis cells contain a large set of enzymes that allow them to carry out an enormous number of bioconversions and degradations. Oxidations, dehydrogenations, epoxidations, hydrolysis, hydroxylations, dehalogenations and desulfurisations have been reported to be performed by R. erythropolis cells or enzymes. This large array of enzymes fully justifies the prospective application of this bacterium in biotechnology.
Tomohiro Tamura - One of the best experts on this subject based on the ideXlab platform.
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Identification of a novel bacteriocin-like protein and structural gene from Rhodococcus erythropolis JCM 2895, using suppression-subtractive hybridization
The Journal of Antibiotics, 2018Co-Authors: Wataru Kitagawa, Miyako Hata, Shinya Mitsuhashi, Tomohiro TamuraAbstract:A novel bacteriocin-like protein and its structural gene ( rap ) were identified from Rhodococcus erythropolis JCM 2895. The rapA and B genes are located on a 5.4-kb circular plasmid, and were obtained using a modified suppression-subtractive hybridization method. The rapA and B genes were heterologously expressed in Rhodococcus sp. or Escherichia coli , and then characterized. The results indicated that RapA is a small, water-soluble, heat-stable antimicrobial protein, and that RapB is an immunity protein against RapA, estimated to be located on the cell membrane. RapA showed antimicrobial activity particularly against R. erythropolis , and the activity persisted even after SDS-PAGE analysis. For the heterologous expressed RapA protein, N-terminal amino acid sequence was also confirmed. This is the first report of a bacteriocin-like substance obtained from the genus Rhodococcus .
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A Quinoline Antibiotic from Rhodococcus erythropolis JCM 6824
The Journal of Antibiotics, 2008Co-Authors: Wataru Kitagawa, Tomohiro TamuraAbstract:A new quinoline antibiotic, aurachin RE, was isolated and identified from a culture broth of Rhodococcus erythropolis JCM 6824. The aurachin RE structure was determined based on NMR and mass spectrometric analysis. The structure is similar to that of aurachin C antibiotics that have been identified from Stigmatella aurantiaca . Compared to aurachin C, however, aurachin RE exhibits a wide and strong antimicrobial spectrum against both high- and low-GC Gram-positive bacteria.
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three types of antibiotics produced from Rhodococcus erythropolis strains
Microbes and Environments, 2008Co-Authors: Wataru Kitagawa, Tomohiro TamuraAbstract:A total of 15 Rhodococcus erythropolis strains were characterized as antibiotic producers and classified into three groups according to their antibiotic spectrum and growth compatibility (strains within a group did not inhibit each other's growth). Each of the antibiotic groups exhibited antibiotic activity against a taxonomically different breadth of bacteria: Group I exhibited antibiotic activity against a broad range of Gram-positives; Group II, mainly against the genus Rhodococcus and some other Gram-positives; and Group III, particularly against R. erythropolis. The antibiotic compounds of the strains belonging to Groups I and II were partially purified from liquid culture media. It was found that each group produces distinct antibiotics. In contrast to the diversity of antibiotic activity, the sequence of the 16S rRNA gene in the analyzed 1,440-nt region was found to be identical in all these 15 Rhodococcus strains. In addition to the antibiotic diversity in R. erythropolis strains, we elucidated the diversity in antibiotic-producing species of the genus Rhodococcus. Thus far, only a few antibiotic-producing strains have been reported in Rhodococcus; however, our results demonstrated that the genus comprises diverse antibiotic producers, and is a good source of new antibiotics.
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characterization of ltsa from Rhodococcus erythropolis an enzyme with glutamine amidotransferase activity
Journal of Bacteriology, 2005Co-Authors: Yasuo Mitani, Tomohiro Tamura, Xianying Meng, Yoichi KamagataAbstract:The nocardioform actinomycete Rhodococcus erythropolis has a characteristic cell wall structure. The cell wall is composed of arabinogalactan and mycolic acid and is highly resistant to the cell wall-lytic activity of lysozyme (muramidase). In order to improve the isolation of recombinant proteins from R. erythropolis host cells (N. Nakashima and T. Tamura, Biotechnol. Bioeng. 86:136-148, 2004), we isolated two mutants, L-65 and L-88, which are susceptible to lysozyme treatment. The lysozyme sensitivity of the mutants was complemented by expression of Corynebacterium glutamicum ltsA, which codes for an enzyme with glutamine amidotransferase activity that results from coupling of two reactions (a glutaminase activity and a synthetase activity). The lysozyme sensitivity of the mutants was also complemented by ltsA homologues from Bacillus subtilis and Mycobacterium tuberculosis, but the homologues from Streptomyces coelicolor and Escherichia coli did not complement the sensitivity. This result suggests that only certain LtsA homologues can confer lysozyme resistance. Wild-type recombinant LtsA from R. erythropolis showed glutaminase activity, but the LtsA enzymes from the L-88 and L-65 mutants displayed drastically reduced activity. Interestingly, an ltsA disruptant mutant, which expressed the mutated LtsA, changed from lysozyme sensitive to lysozyme resistant when NH4Cl was added into the culture media. The glutaminase activity of the LtsA mutants inactivated by site-directed mutagenesis was also restored by addition of NH4Cl, indicating that NH3 can be used as an amide donor molecule. Taken together, these results suggest that LtsA is critically involved in mediating lysozyme resistance in R. erythropolis cells.
Elen Aquino Perpetuo - One of the best experts on this subject based on the ideXlab platform.
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copper biosorption by Rhodococcus erythropolis isolated from the sossego mine pa brazil
Journal of materials research and technology, 2019Co-Authors: Marcela Dos Passos Galluzzi Baltazar, Louise Hase Gracioso, Ingrid Regina Avanzi, Bruno Karolski, Jorge Alberto Soares Tenorio, Claudio Augusto Oller Do Nascimento, Elen Aquino PerpetuoAbstract:Abstract This work evaluates the copper biosorption capacity (Cu2+) by the biomass of a bacterium strain identified as Rhodococcus erythropolis isolated from copper mining environmental samples. The copper uptake was analyzed under different influences of pH, biomass concentration, and metal concentration. The total copper uptake was measured using ICP-OES and the metal adsorption capacity calculated by construction of Langmuir and Freundlich isotherm models. R. erythropolis biomass is a potential material to treat and to remove copper from low concentration of aqueous contaminated effluents reaching a total absorption of 68.03 mg of Cu2+ per gram of biomass according to the Langmuir model at pH = 6, the optimal pH for maximum copper uptake. Our results showed a unique absorption rate when compared to other bacteria belonging to the Rhodococcus genus or even when compared to other bacteria genera able to adsorb metal from aqueous environments.
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Copper biosorption by Rhodococcus erythropolis isolated from the Sossego Mine – PA – Brazil
Elsevier, 2019Co-Authors: Marcela Dos Passos Galluzzi Baltazar, Louise Hase Gracioso, Ingrid Regina Avanzi, Bruno Karolski, Jorge Alberto Soares Tenorio, Claudio Augusto Oller Do Nascimento, Elen Aquino PerpetuoAbstract:This work evaluates the copper biosorption capacity (Cu2+) by the biomass of a bacterium strain identified as Rhodococcus erythropolis isolated from copper mining environmental samples. The copper uptake was analyzed under different influences of pH, biomass concentration, and metal concentration. The total copper uptake was measured using ICP-OES and the metal adsorption capacity calculated by construction of Langmuir and Freundlich isotherm models. R. erythropolis biomass is a potential material to treat and to remove copper from low concentration of aqueous contaminated effluents reaching a total absorption of 68.03 mg of Cu2+ per gram of biomass according to the Langmuir model at pH = 6, the optimal pH for maximum copper uptake. Our results showed a unique absorption rate when compared to other bacteria belonging to the Rhodococcus genus or even when compared to other bacteria genera able to adsorb metal from aqueous environments. Keywords: Metal biosorption, Bioprocess, Hydrometallurgy, Biomass, Rhodococcu
Manuela M R Da Fonseca - One of the best experts on this subject based on the ideXlab platform.
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adaptation of Rhodococcus erythropolis cells to high concentrations of toluene
Applied Microbiology and Biotechnology, 2007Co-Authors: Carla C. C. R. De Carvalho, Vanessa Fatal, S S Alves, Manuela M R Da FonsecaAbstract:Cells of Rhodococcus erythropolis DCL14 were adapted to increasing toluene concentrations in a mechanically stirred reactor. When the initial non-adapted cells were placed in contact with toluene, only 10.5% of cells remained viable after 1 h in the presence of 20% (v/v) toluene, while 8.6% of cells were viable after 28 h in the presence of an organic phase containing 80% (v/v) toluene in n-dodecane. Cell adaptation was studied by following the toluene consumption rate, the viability of the cell population, and the composition of the bacteria cellular membrane in the presence of increasing concentrations of toluene in the reactor. A maximum toluene concentration of 4.9 M, which corresponds to 52.4% (v/v) toluene in the organic phase, was achieved, toluene being consumed at 10.7 mg/(h mg protein). The adapted cells showed a substantially increased resistance to 50% ethanol and to concentrations of Betadine® and Micropur® tablets currently used in water purification, when compared to non-adapted cells.
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adaptation of Rhodococcus erythropolis dcl14 to growth on n alkanes alcohols and terpenes
Applied Microbiology and Biotechnology, 2005Co-Authors: Carla C. C. R. De Carvalho, Manuela M R Da Fonseca, Beatriz Parrenomarchante, Grit Neumann, Hermann J HeipieperAbstract:Rhodococcus erythropolis DCL14 has the ability to convert the terpene (−)-carveol to the valuable flavour compound (−)-carvone when growing on a wide range of carbon sources. To study the effect of carbon and energy sources such as alkanes, alkanols and terpenes on the biotechnological process, the cellular adaptation at the level of fatty acid composition of the membrane phospholipids and the (−)-carvone production were examined. All tested carbon sources caused a dose-dependent increase in the degree of saturation of the fatty acids. The exception was observed with short-chain alcohols such as methanol and ethanol, to which the cells adapted with a concentration-dependent decrease in the saturation degree of the membrane phospholipids. This influence of the different carbon sources on the rigidity of the cell membrane also had an impact on the (−)-carvone productivity of the strain.
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degradation of hydrocarbons and alcohols at different temperatures and salinities by Rhodococcus erythropolis dcl14
FEMS Microbiology Ecology, 2005Co-Authors: Carla C. C. R. De Carvalho, Manuela M R Da FonsecaAbstract:Rhodococcus erythropolis DCL14 cells were able to metabolise C5–C16 hydrocarbons and C1–C12 alcohols as sole carbon and energy sources, both at 15 and 28 °C. Metabolic activity was also observed at 1.00%, 1.95% and 2.50% sodium chloride. Almost complete degradation of n-, iso- and cyclo-alkanes and aromatic compounds present in fuel oil was achieved after 9 months, 60% being consumed in the first three months. The results from the conditions tested here suggest that this type of bacterium could be involved in bioremediation processes in marine environments such as the Atlantic, Pacific and Indian Ocean.
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mycobacterium sp Rhodococcus erythropolis and pseudomonas putida behavior in the presence of organic solvents
Microscopy Research and Technique, 2004Co-Authors: Carla C. C. R. De Carvalho, Manuela M R Da Fonseca, Alexandra A R L Da Cruz, Marienoelle Pons, H M Pinheiro, Joaquim M S Cabral, Bruno Sommer Ferreira, Pedro FernandesAbstract:This work aimed at studying the behavior and tolerance of Mycobacterium sp. NRRL B-3805, Rhodococcus erythropolis DCL14 and Pseudomonas putida S12 cells in the presence of various concentrations of water miscible (ethanol, butanol, and dimethylformamide, up to 50% v/v) and water immiscible solvents (dodecane, bis(2-ethylhexyl) phthalate and toluene, up to 5% v/v). When incubated in the presence of these solvents, the cells were found to have lower tolerance to butanol and toluene than to the remaining solvents. Nevertheless, the concentrations of solvents endured by the tested strains show that they are quite solvent-tolerant, confirming their potential as biocatalysts in nonconventional systems. Microscopic observation of samples showed that the hydrophobic Mycobacterium sp. and R. erythropolis cells were able to aggregate to protect the population under stress conditions. Comparison of the results obtained at the single cell level by fluorescence microscopy and colony development on agar plates indicated that the primary effects of most solvents tested were on the cell membrane and replicating capability of the cells.
Hiroshi Takagi - One of the best experts on this subject based on the ideXlab platform.
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utilization of atmospheric ammonia by an extremely oligotrophic bacterium Rhodococcus erythropolis n9t 4
Journal of Bioscience and Bioengineering, 2014Co-Authors: Nobuyuki Yoshida, Satoshi Inaba, Hiroshi TakagiAbstract:Rhodococcus erythropolis N9T-4 shows extremely oligotrophic growth and requires CO2 for its growth. In this report, nitrogen sources for the oligotrophic growth of N9T-4 were examined. As is true for most other bacteria, N9T-4 preferred ammonium salt to nitrate as the nitrogen source on an inorganic minimum medium without carbon sources. Interestingly, N9T-4 could also grow on the minimal medium solidified by agarose or silica gel without carbon and nitrogen sources, suggesting that this bacterium is also oligotrophic for nitrogen. We can rule out the possibility of diazotrophic growth of this bacterium, because nitrogenase activity was not detected in the cells and the putative gene encoding nitrogenase was not found in N9T-4 genome. DNA microarray analysis revealed that one of the ammonium transporter genes (amtB) was strongly upregulated 40–50 fold higher under oligotrophic conditions than under heterotrophic conditions. Disruption of amtB led to a growth defect under nitrogen-limiting conditions. Furthermore, additional ammonia vapor enhanced the growth of N9T-4 on the minimum medium without nitrogen sources in a closed culture system. These results suggest that N9T-4 utilizes the trace amount of atmospheric ammonia as the nitrogen source.
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gene expression analysis of methylotrophic oxidoreductases involved in the oligotrophic growth of Rhodococcus erythropolis n9t 4
Bioscience Biotechnology and Biochemistry, 2011Co-Authors: Nobuyuki Yoshida, Takuya Hayasaki, Hiroshi TakagiAbstract:Rhodococcus erythropolis N9T-4 shows extremely oligotrophic growth requiring atmospheric CO2 without any additional carbon or energy source. We performed a gene expression analysis of the oxidoreductases, which are involved in methanol metabolism, under various growth and induction conditions in N9T-4. A real-time PCR analysis revealed that the genes encoding NAD-dependent formaldehyde dehydrogenase (nFADH) and N,N′-dimethyl-4-nitrosoaniline-dependent methanol dehydrogenase (MDH) were strongly expressed under the oligotrophic conditions at levels of 20–100 fold those under heterotrophic conditions, in which n-tetradecane was used as the sole carbon source, while glucose did not affect the gene expression pattern in a minimum medium. The genes encoding mycothiol-dependent formaldehyde dehydrogenase (mFADH) and formate dehydrogenase were not induced under oligotrophic conditions, although mFADH expression was observed when formaldehyde was added to the induction medium. These results suggest that N9T-4 had ...
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an extremely oligotrophic bacterium Rhodococcus erythropolis n9t 4 isolated from crude oil
Journal of Bacteriology, 2007Co-Authors: Naoko Ohhata, Nobuyuki Yoshida, Hiroshi Egami, Tohoru Katsuragi, Yoshiki Tani, Hiroshi TakagiAbstract:Rhodococcus erythropolis N9T-4, which was isolated from crude oil, showed extremely oligotrophic growth and formed its colonies on a minimal salt medium solidified using agar or silica gel without any additional carbon source. N9T-4 did not grow under CO2-limiting conditions but could grow on a medium containing NaHCO3 under the same conditions, suggesting that the oligotrophic growth of N9T-4 depends on CO2. Proteomic analysis of N9T-4 revealed that two proteins, with molecular masses of 45 and 55 kDa, were highly induced under the oligotrophic conditions. The primary structures of these proteins exhibited striking similarities to those of methanol: N,N′-dimethyl-4-nitrosoaniline oxidoreductase and an aldehyde dehydrogenase from Rhodococcus sp. These enzyme activities were three times higher under oligotrophic conditions than under n-tetradecane-containing heterotrophic conditions, and gene disruption for the aldehyde dehydrogenase caused a lack of growth on the minimal salt medium. Furthermore, 3-hexulose 6-phosphate synthase and phospho-3-hexuloisomerase activities, which are key enzymes in the ribulose monophosphate pathway in methylotrophic bacteria, were detected specifically in the cell extract of oligotrophically grown N9T-4. These results suggest that CO2 fixation involves methanol (formaldehyde) metabolism in the oligotrophic growth of R. erythropolis N9T-4.