WorldWideScience

Sample records for cupriavidus basilensis hmf14

  1. Identification and characterization of the furfural and 5-(hydroxymethyl)furfural degradation pathways of Cupriavidus basilensis HMF14

    OpenAIRE

    Koopman, F.; Wierckx, N.; Winde, de, J.H.; Ruijssenaars, H.J.

    2010-01-01

    The toxic fermentation inhibitors in lignocellulosic hydrolysates pose significant problems for the production of second-generation biofuels and biochemicals. Among these inhibitors, 5-(hydroxymethyl)furfural (HMF) and furfural are specifically notorious. In this study, we describe the complete molecular identification and characterization of the pathway by which Cupriavidus basilensis HMF14 metabolizes HMF and furfural. The identification of this pathway enabled the construction of an HMF an...

  2. Identification and characterization of the furfural and 5-(hydroxymethyl)furfural degradation pathways of Cupriavidus basilensis HMF14

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, F.; De Winde, J.H. [Bio-Based Sustainable Industrial Chemistry (B-Basic), Delft University of Technology, Department of Biotechnology, Julianalaan 67, 2628 BC, Delft (Netherlands); Wierckx, N. [Kluyver Centre for Genomics of Industrial Fermentation, P.O. Box 5057, 2600 GB, Delft (Netherlands); Ruijssenaars, H.J. [Netherlands Organization for Applied Scientific Research, Quality of Life, Department of Bioconversion, Julianalaan 67, 2628 BC, Delft (Netherlands); O' Neal Ingram, L. (ed.) [University of Florida, Gainesville, Gainesville, FL (United States)

    2010-03-16

    The toxic fermentation inhibitors in lignocellulosic hydrolysates pose significant problems for the production of second-generation biofuels and biochemicals. Among these inhibitors, 5-(hydroxymethyl) furfural (HMF) and furfural are specifically notorious. In this study, we describe the complete molecular identification and characterization of the pathway by which Cupriavidus basilensis HMF14 metabolizes HMF and furfural. The identification of this pathway enabled the construction of an HMF and furfural-metabolizing Pseudomonas putida. The genetic information obtained furthermore enabled us to predict the HMF and furfural degrading capabilities of sequenced bacterial species that had not previously been connected to furanic aldehyde metabolism. These results pave the way for in situ detoxification of lignocellulosic hydrolysates, which is a major step toward improved efficiency of utilization of lignocellulosic feedstock.

  3. Identification and characterization of the furfural and 5-(hydroxymethyl)furfural degradation pathways of Cupriavidus basilensis HMF14

    Science.gov (United States)

    Koopman, Frank; Wierckx, Nick; de Winde, Johannes H.; Ruijssenaars, Harald J.

    2010-01-01

    The toxic fermentation inhibitors in lignocellulosic hydrolysates pose significant problems for the production of second-generation biofuels and biochemicals. Among these inhibitors, 5-(hydroxymethyl)furfural (HMF) and furfural are specifically notorious. In this study, we describe the complete molecular identification and characterization of the pathway by which Cupriavidus basilensis HMF14 metabolizes HMF and furfural. The identification of this pathway enabled the construction of an HMF and furfural-metabolizing Pseudomonas putida. The genetic information obtained furthermore enabled us to predict the HMF and furfural degrading capabilities of sequenced bacterial species that had not previously been connected to furanic aldehyde metabolism. These results pave the way for in situ detoxification of lignocellulosic hydrolysates, which is a major step toward improved efficiency of utilization of lignocellulosic feedstock. PMID:20194784

  4. Isolation and characterization of Cupriavidus basilensis HMF14 for biological removal of inhibitors from lignocellulosic hydrolysatembt

    NARCIS (Netherlands)

    Wierckx, N.; Koopman, F.; Bandounas, L.; Winde, J.H.de; Ruijssenaars, H.J.

    2010-01-01

    The formation of toxic fermentation inhibitors such as furfural and 5-hydroxy-2-methylfurfural (HMF) during acid (pre-)treatment of lignocellulose, calls for the efficient removal of these compounds. Lignocellulosic hydrolysates can be efficiently detoxified biologically with microorganisms that

  5. Identification and characterization of the furfural and 5-(hydroxymethyl)furfural degradation pathways of Cupriavidus basilensis HMF14

    NARCIS (Netherlands)

    Koopman, F.; Wierckx, N.; Winde, J.H.de; Ruijssenaars, H.J.

    2010-01-01

    The toxic fermentation inhibitors in lignocellulosic hydrolysates pose significant problems for the production of second-generation biofuels and biochemicals. Among these inhibitors, 5-(hydroxymethyl) furfural (HMF) and furfural are specifically notorious. In this study, we describe the complete

  6. Characterization and genomic analysis of kraft lignin biodegradation by the beta-proteobacterium Cupriavidus basilensis B-8

    Directory of Open Access Journals (Sweden)

    Shi Yan

    2013-01-01

    Full Text Available Abstract Background Lignin materials are abundant and among the most important potential sources for biofuel production. Development of an efficient lignin degradation process has considerable potential for the production of a variety of chemicals, including bioethanol. However, lignin degradation using current methods is inefficient. Given their immense environmental adaptability and biochemical versatility, bacterial could be used as a valuable tool for the rapid degradation of lignin. Kraft lignin (KL is a polymer by-product of the pulp and paper industry resulting from alkaline sulfide treatment of lignocellulose, and it has been widely used for lignin-related studies. Results Beta-proteobacterium Cupriavidus basilensis B-8 isolated from erosive bamboo slips displayed substantial KL degradation capability. With initial concentrations of 0.5–6 g L-1, at least 31.3% KL could be degraded in 7 days. The maximum degradation rate was 44.4% at the initial concentration of 2 g L-1. The optimum pH and temperature for KL degradation were 7.0 and 30°C, respectively. Manganese peroxidase (MnP and laccase (Lac demonstrated their greatest level of activity, 1685.3 U L-1 and 815.6 U L-1, at the third and fourth days, respectively. Many small molecule intermediates were formed during the process of KL degradation, as determined using GC-MS analysis. In order to perform metabolic reconstruction of lignin degradation in this bacterium, a draft genome sequence for C. basilensis B-8 was generated. Genomic analysis focused on the catabolic potential of this bacterium against several lignin-derived compounds. These analyses together with sequence comparisons predicted the existence of three major metabolic pathways: β-ketoadipate, phenol degradation, and gentisate pathways. Conclusion These results confirmed the capability of C. basilensis B-8 to promote KL degradation. Whole genomic sequencing and systematic analysis of the C. basilensis B-8 genome

  7. Taxonomy of the genus Cupriavidus: a tale of lost and found.

    Science.gov (United States)

    Vandamme, Peter; Coenye, Tom

    2004-11-01

    DNA-DNA hybridization experiments and an evaluation of phenotypic characteristics, DNA base ratios and 16S rRNA gene sequences demonstrated that Wautersia eutropha (Davies 1969) Vaneechoutte et al. 2004, the type species of the genus Wautersia, is a later synonym of Cupriavidus necator Makkar and Casida 1987, the type species of the genus Cupriavidus. In conformity with Rules 15, 17, 23a and 37a(1) of the International Code of Nomenclature of Bacteria, the genus name Cupriavidus has priority over the genus name Wautersia, and all other members of the genus Wautersia are reclassified into Cupriavidus as Cupriavidus basilensis comb. nov. (type strain LMG 18990(T)=DSM 11853(T)), Cupriavidus campinensis comb. nov. (type strain LMG 19282(T)=CCUG 44526(T)), Cupriavidus gilardii comb. nov. (type strain LMG 5886(T)=CCUG 38401(T)), Cupriavidus metallidurans comb. nov. (type strain LMG 1195(T)=DSM 2839(T)), Cupriavidus oxalaticus comb. nov. (type strain LMG 2235(T)=CCUG 2086(T)=DSM 1105(T)), Cupriavidus pauculus comb. nov. (type strain LMG 3244(T)=CCUG 12507(T)), Cupriavidus respiraculi comb. nov. (type strain LMG 21510(T)=CCUG 46809(T)) and Cupriavidus taiwanensis comb. nov. (type strain LMG 19424(T)=CCUG 44338(T)).

  8. A Fatal Case of Community Acquired Cupriavidus Pauculus Pneumonia

    Directory of Open Access Journals (Sweden)

    Almasy Emoke

    2016-10-01

    Full Text Available Introduction: Cupriavidus pauculus is a rarely isolated non-fermentative, aerobic bacillus, which occasionally causes severe human infections, especially in immunocompromised patients. Strains have been isolated from various clinical and environmental sources.

  9. A Fatal Case of Community Acquired Cupriavidus Pauculus Pneumonia

    OpenAIRE

    Almasy Emoke; Szederjesi Janos; Rad Paul; Georgescu Anca

    2016-01-01

    Introduction: Cupriavidus pauculus is a rarely isolated non-fermentative, aerobic bacillus, which occasionally causes severe human infections, especially in immunocompromised patients. Strains have been isolated from various clinical and environmental sources.

  10. Cupriavidus pauculus bacteremia in a child on extracorporeal membrane oxygenation.

    Science.gov (United States)

    Uzodi, Adaora S; Schears, Gregory J; Neal, James R; Henry, Nancy K

    2014-01-01

    We report a case of bacteremia secondary to Cupriavidus pauculus in a 15-month-old boy on extracorporeal membrane oxygenation (ECMO). The source of the organism was water in the thermoregulator reservoir. The child responded well to cefepime and ciprofloxacin, a delayed oxygenator change out and replacement of the thermoregulator reservoir with a unit that was cleaned and decontaminated with sodium hypochlorite. Isolation of Cupriavidus pauculus from a patient on ECMO support should raise suspicion of the reservoir as a source.

  11. Improved production of 2,5-furandicarboxylic acid by overexpression of 5-hydroxymethylfurfural oxidase and 5-hydroxymethylfurfural/furfural oxidoreductase in Raoultella ornithinolytica BF60.

    Science.gov (United States)

    Yuan, Haibo; Li, Jianghua; Shin, Hyun-Dong; Du, Guocheng; Chen, Jian; Shi, Zhongping; Liu, Long

    2018-01-01

    2,5-Furandicarboxylic acid (FDCA) is a promising bio-based building block and can be produced by biotransformation of 5-hydroxymethylfurfural (HMF). To improve the FDCA production, two genes-one encoding HMF oxidase (HMFO; from Methylovorus sp. strain MP688) and another encoding for HMF/Furfural oxidoreductase (HmfH; from Cupriavidus basilensis HMF14)-were introduced into Raoultella ornithinolytica BF60. The FDCA production in the engineered whole-cell biocatalyst increased from 51.0 to 93.6mM, and the molar conversion ratio of HMF to FDCA increased from 51.0 to 93.6%. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Nosocomial transmission of Cupriavidus pauculus during extracorporeal membrane oxygenation.

    Science.gov (United States)

    Stovall, S H; Wisdom, C; McKamie, W; Ware, W; Dedman, H; Fiser, R T

    2010-01-01

    Patients undergoing extracorporeal membrane oxygenation (ECMO) are at increased risk of infection. We present the first known report of nosocomial infection with Cupriavidus pauculus attributable to contamination from ECMO equipment and describe the measures taken to halt subsequent infections. A cluster of infections in ECMO patients should prompt team members to consider contamination of equipment with environmental pathogens as a possible cause.

  13. The initial metabolic conversion of levulinic acid in Cupriavidus necator.

    Science.gov (United States)

    Jaremko, Matt; Yu, Jian

    2011-09-20

    Levulinic acid or 4-ketovaleric acid is a potential renewable substrate for production of polyhydroxyalkanoates. In this work, the initial reactions of LA metabolism by Cupriavidus necator were examined in vitro. The organic acid was converted by membrane-bound crude enzymes obtained from the cells pre-grown on LA, while no LA activity was detected from cells pre-grown on acetic acid. Acetyl-CoA and propionyl-CoA were two major intermediates in the initial reactions of LA conversion. A mass balance on propionyl-CoA accounts for 84 mol% of LA added in vitro. It explains an interesting phenomenon that 3-hydroxbutyrate and 3-hydroxyvalerate are two major monomers of the biopolyester formed from LA, instead of 4-hydroxvalerate that has the similar chemical structure of LA as the precursor. A Monod model was used to describe the kinetics of LA utilization as a sole carbon source or a co-substrate of glucose and fructose. The μ(max) and K(m) of LA alone were 0.26 h⁻¹ and 0.01 g/L, respectively. The content and composition of PHA are also dependent on the culture conditions such as carbon to nitrogen ratio. The in vitro observation is supported by the high utilization rate of LA and the high molar percentage of 3HB and 3HV in the PHA derived from LA. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Study of interaction of the bacterium cupriavidus metallidurans with strontium

    International Nuclear Information System (INIS)

    Boussiga, Rim

    2010-01-01

    Cupriavidus metallidurans strain Ch 34 (previously known as Ralstonia metallidurans, Ralstonia eutropha, and Alcaligenes eutrophus) is an ideal subject to study heavy metal disturbance of cellular processes. Moreover, the capacity of C. metallidurans Ch 34 for in situ bioremediation was assessed and proved to be feasible on pilot scale. In this work, the molecular and physiological response to strontium cations (Sr 2+ ) by C.metallidurans Ch 34 was studied. Results showed that C. metallidurans Ch 34 resisted to high concentrations of Sr (120 m M) and that this resistance is not linked to the presence of its 2 large plasmid pMOL30 or pMOL28. During this study, a tctCBA-dependent tripartite tricarboxylate transport (TTT) system in strain Ch 34 was discovered. Transmission Electron Microscopy (TEM) observation of C.metallidurans challenged with strontium confirms the precipitation of Sr 2+ ) directly onto the surface of cells, inside and in the microenvironment around the cells. These results highlight the potential of C. metalliduras Ch 34 to endure environmental extremes and suggest that in situ bioremediation of Sr-containing waste with Ch 34 might be feasible.

  15. Uranium and selenium resistance in Cupriavidus metallidurans CH34

    International Nuclear Information System (INIS)

    Avoscan, L.; Untereiner, G.; Carriere, M.; Gouget, B.; Degrouard, J.

    2007-01-01

    Cupriavidus metallidurans CH34, a soil bacterium, is known to resist a variety of heavy metals and metalloids. Its capacity to resist, accumulate and transform selenium (Se as selenite or selenate) and uranium (U as uranyl-carbonate and uranyl-citrate) was investigated. C. metallidurans CH34 resists to high U concentrations (up to 10 mM) whatever its speciation. However, no major accumulation could be measured: U-carbonate and U-citrate are not bio-available for the bacteria. The anaerobic response of C. metallidurans CH34 to U will be looked for. C. metallidurans CH34 resists to high Se concentrations (up to 4 mM of selenite and 8 mM of selenate). Bacteria exposed to 2 mM of selenite accumulate 25 times more Se than when they are exposed to same concentration of selenate. Se resistance is characterized by the reduction of oxy-anions in the bacteria. Selenite is reduced to elemental Se by an intracellular process, but the metabolic fate of selenate is unknown. By combining three methods of speciation (X-ray absorption spectroscopy (XANES and EXAFS), HPLC-ICP-MS and SDS-PAGE coupled with particle induced X-ray emission (PIXE)), we both identified and specified the chemical intermediates formed by this bacterium upon exposure to these oxy-anions. Two mechanisms of reduction of Se oxides in C. metallidurans CH34 were highlighted. Assimilation transforms selenite and selenate into organic Se, identified as seleno-methionine and leads to its non-specific incorporation into bacterial proteins (presence of selenious proteins). Detoxication precipitates selenite in nano-particles of elemental Se. (authors)

  16. First case of pneumonia caused by Cupriavidus pauculus in an infant in the Gulf Cooperation Council.

    Science.gov (United States)

    Yahya, Raghda; Alyousef, Wafaa; Omara, Abdelwahab; Alamoudi, Suha; Alshami, Alanoud; Abdalhamid, Baha

    2017-02-28

    Cupriavidus pauculus is an emerging organism causing infections in immunocompromised and immunocompetent patients. We report a C.pauculus pneumonia case susceptible to cefepime in an infant with end-stage renal failure. To our knowledge, this is the first case report of C. pauculus causing respiratory infections in the Gulf Cooperation Council.

  17. Draft Genome Sequence of an Active Heterotrophic Nitrifier-Denitrifier, Cupriavidus pauculus UM1.

    Science.gov (United States)

    Putonti, Catherine; Polley, Nathaniel; Castignetti, Domenic

    2018-02-08

    Here, we present the draft genome sequence of Cupriavidus pauculus UM1, a metal-resistant heterotrophic nitrifier-denitrifier capable of synthesizing nitrite from pyruvic oxime. The size of the genome is 7,402,815 bp with a GC content of 64.8%. This draft assembly consists of 38 scaffolds. Copyright © 2018 Putonti et al.

  18. Draft Genome Sequence of an Active Heterotrophic Nitrifier-Denitrifier, Cupriavidus pauculus UM1

    OpenAIRE

    Putonti, Catherine; Polley, Nathaniel; Castignetti, Domenic

    2018-01-01

    ABSTRACT Here, we present the draft genome sequence of Cupriavidus pauculus UM1, a metal-resistant heterotrophic nitrifier-denitrifier capable of synthesizing nitrite from pyruvic oxime. The size of the genome is 7,402,815 bp with a GC content of 64.8%. This draft assembly consists of 38 scaffolds.

  19. Cupriavidus pauculus (Ralstonia paucula) concomitant meningitis and septicemia in a neonate: First case report from India

    OpenAIRE

    S Duggal; R Gur; R Nayar; S R Rongpharpi; D Jain; R K Gupta

    2013-01-01

    Ralstonia paucula (formerly classified as CDC (Centre for Disease Control) group IVc-2, Wautersia paucula; recently renamed as Cupriavidus pauculus) is an environmental Gram-negative bacillus isolated from water sources and can cause serious human infections. Patients recover bacteriologically indicating low virulence. A total of 32 cases have been reported world-wide, but no isolation has ever been reported from cerebrospinal fluid or in India. The first case of R. paucula meningitis and sep...

  20. Quantitative Raman Spectroscopy Analysis of Polyhydroxyalkanoates Produced by Cupriavidus necator H16

    Czech Academy of Sciences Publication Activity Database

    Samek, Ota; Obruča, S.; Šiler, Martin; Sedláček, P.; Benešová, P.; Kučera, D.; Márová, I.; Ježek, Jan; Bernatová, Silvie; Zemánek, Pavel

    2016-01-01

    Roč. 16, č. 11 (2016), 1808:1-7 ISSN 1424-8220 R&D Projects: GA ČR(CZ) GA15-20645S; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : Raman spectroscopy * Cupriavidus necator H16 * polyhydroxyalkanoates Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.677, year: 2016

  1. Purification and Characterization of the Acetone Carboxylase of Cupriavidus metallidurans Strain CH34

    Science.gov (United States)

    Rosier, Caroline; Leys, Natalie; Henoumont, Céline; Mergeay, Max

    2012-01-01

    Acetone carboxylase (Acx) is a key enzyme involved in the biodegradation of acetone by bacteria. Except for the Helicobacteraceae family, genome analyses revealed that bacteria that possess an Acx, such as Cupriavidus metallidurans strain CH34, are associated with soil. The Acx of CH34 forms the heterohexameric complex α2β2γ2 and can carboxylate only acetone and 2-butanone in an ATP-dependent reaction to acetoacetate and 3-keto-2-methylbutyrate, respectively. PMID:22492439

  2. The complete multipartite genome sequence of Cupriavidus necator JMP134, a versatile pollutant degrader.

    Directory of Open Access Journals (Sweden)

    Athanasios Lykidis

    Full Text Available BACKGROUND: Cupriavidus necator JMP134 is a Gram-negative beta-proteobacterium able to grow on a variety of aromatic and chloroaromatic compounds as its sole carbon and energy source. METHODOLOGY/PRINCIPAL FINDINGS: Its genome consists of four replicons (two chromosomes and two plasmids containing a total of 6631 protein coding genes. Comparative analysis identified 1910 core genes common to the four genomes compared (C. necator JMP134, C. necator H16, C. metallidurans CH34, R. solanacearum GMI1000. Although secondary chromosomes found in the Cupriavidus, Ralstonia, and Burkholderia lineages are all derived from plasmids, analyses of the plasmid partition proteins located on those chromosomes indicate that different plasmids gave rise to the secondary chromosomes in each lineage. The C. necator JMP134 genome contains 300 genes putatively involved in the catabolism of aromatic compounds and encodes most of the central ring-cleavage pathways. This strain also shows additional metabolic capabilities towards alicyclic compounds and the potential for catabolism of almost all proteinogenic amino acids. This remarkable catabolic potential seems to be sustained by a high degree of genetic redundancy, most probably enabling this catabolically versatile bacterium with different levels of metabolic responses and alternative regulation necessary to cope with a challenging environment. From the comparison of Cupriavidus genomes, it is possible to state that a broad metabolic capability is a general trait for Cupriavidus genus, however certain specialization towards a nutritional niche (xenobiotics degradation, chemolithoautotrophy or symbiotic nitrogen fixation seems to be shaped mostly by the acquisition of "specialized" plasmids. CONCLUSIONS/SIGNIFICANCE: The availability of the complete genome sequence for C. necator JMP134 provides the groundwork for further elucidation of the mechanisms and regulation of chloroaromatic compound biodegradation.

  3. The Complete Multipartite Genome Sequence of Cupriavidus necator JMP134, a Versatile Pollutant Degrader

    Energy Technology Data Exchange (ETDEWEB)

    Lykidis, Athanasios; Perez-Pantoja, Danilo; Ledger, Thomas; Mavromatis, Kostantinos; Anderson, Iain J.; Ivanova, Natalia N.; Hooper, Sean D.; Lapidus, Alla; Lucas, Susan; Gonzalez, Bernardo; Kyrpides, Nikos C.

    2010-02-01

    Cupriavidus necator JMP134 (formerly Ralstonia eutropha JMP134) is a Gram-negative {beta}-proteobacterium able to degrade a variety of chloroaromatic compounds and chemically-related pollutants. It was originally isolated based on its ability to use 2,4 dichlorophenoxyacetic acid (2,4-D) as a sole carbon and energy source [1]. In addition to 2,4-D, this strain can also grow on a variety of aromatic substrates, such as 4-chloro-2-methylphenoxyacetate (MCPA), 3-chlorobenzoic acid (3-CB) [2], 2,4,6-trichlorophenol [3], and 4-fluorobenzoate [4]. The genes necessary for 2,4-D utilization have been identified. They are located in two clusters on plasmid pPJ4: tfd{sub I} and tfd{sub II} [5,6,7,8]. The sequence and analysis of plasmid pJP4 was reported and a congruent model for bacterial adaptation to chloroaromatic pollutants was proposed [9]. According to this model, catabolic gene clusters assemble in a modular manner into broad-host-range plasmid backbones by means of repeated chromosomal capture events. Cupriavidus and related Burkholderia genomes are typically multipartite, composed of two large replicons (chromosomes) accompanied by classical plasmids. Previous work with Burkholderia xenovorans LB400 revealed a differential gene distribution with core functions preferentially encoded by the larger chromosome and secondary functions by the smaller [10]. It has been proposed that the secondary chromosomes in many bacteria originated from ancestral plasmids which, in turn, had been the recipient of genes transferred earlier from ancestral primary chromosomes [11]. The existence of multiple Cupriavidus and Burkholderia genomes provides the opportunity for comparative studies that will lead to a better understanding of the evolutionary mechanisms for the formation of multipartite genomes and the relation with biodegradation abilities.

  4. Tolerance to and Accumulation of Cadmium, Copper, and Zinc by Cupriavidus necator

    Directory of Open Access Journals (Sweden)

    Rayssa Pereira Vicentin

    2018-03-01

    Full Text Available ABSTRACT Preliminary results of in vitro experiments with multicontaminated soils and solid media indicated that nodulating diazotrophic bacteria of the genus Cupriavidus are promising for the remediation of contaminated environments due to their symbiosis with legumes and metal tolerance. Thus, strains of Cupriavidus spp. (LMG 19424T, UFLA 01-659, UFLA 01-663, and UFLA 02-71 were tested for their ability to tolerate and bioaccumulate cadmium (Cd, copper (Cu, and zinc (Zn in Luria-Bertani broth. Changes in the growth pattern of Cupriavidus strains in the presence or absence of heavy metals were analyzed by scanning electron microscopy and metal allocation by transmission electron microscopy, to clarify the mechanisms of bioremediation. Highest tolerance was detected for strain UFLA 01-659 (minimum inhibitory concentration of 5, 4.95, and 14.66 mmol L−1 of Cd, Cu, and Zn, respectively. Among the removal rates of the metals tested (9.0, 4.6, and 3.2 mg L−1 of Cd, Cu, and Zn, respectively, the bacterial activity was clearly highest for Cd. The efficiency of strain UFLA 01-659 in removing the heavy metals is associated with its high biomass production and/or higher contents of heavy metals adsorbed and absorbed in the biomass. In response to the presence of heavy metals in the liquid culture medium, the bacteria produced exopolysaccharides and small and aggregated cells. However, these responses varied according to the strains and heavy metals. Regarding allocation, all heavy metals were adsorbed on the cell wall and membrane, whereas complexation was observed intracellularly and only for Cu and Zn. These results indicate the possibility of using C. necator UFLA 01-659 for remediation in areas with very high Cd, Cu, and Zn contents.

  5. Cupriavidus pauculus (Ralstonia paucula) concomitant meningitis and septicemia in a neonate: first case report from India.

    Science.gov (United States)

    Duggal, S; Gur, R; Nayar, R; Rongpharpi, S R; Jain, D; Gupta, R K

    2013-01-01

    Ralstonia paucula (formerly classified as CDC (Centre for Disease Control) group IVc-2, Wautersia paucula; recently renamed as Cupriavidus pauculus) is an environmental Gram-negative bacillus isolated from water sources and can cause serious human infections. Patients recover bacteriologically indicating low virulence. A total of 32 cases have been reported world-wide, but no isolation has ever been reported from cerebrospinal fluid or in India. The first case of R. paucula meningitis and septicemia is being reported here along with the brief summary of cases reported world-wide.

  6. Cupriavidus pauculus (Ralstonia paucula concomitant meningitis and septicemia in a neonate: First case report from India

    Directory of Open Access Journals (Sweden)

    S Duggal

    2013-01-01

    Full Text Available Ralstonia paucula (formerly classified as CDC (Centre for Disease Control group IVc-2, Wautersia paucula; recently renamed as Cupriavidus pauculus is an environmental Gram-negative bacillus isolated from water sources and can cause serious human infections. Patients recover bacteriologically indicating low virulence. A total of 32 cases have been reported world-wide, but no isolation has ever been reported from cerebrospinal fluid or in India. The first case of R. paucula meningitis and septicemia is being reported here along with the brief summary of cases reported world-wide.

  7. A case of newborn with community acquired pneumonia caused by Cupriavidus pauculus.

    Science.gov (United States)

    Aydın, Banu; Dilli, Dilek; Zenciroğlu, Ayşegül; Okumuş, Nurullah; Ozkan, Sengül; Tanır, Gönül

    2012-01-01

    Cupriavidus pauculus is a gram-negative, aerobic, non-spore forming, non-fermentative motile bacillus. The bacillus can be isolated from water, bottled mineral water, and water from ultrafiltration systems in hospital setting. C. pauculus rarely causes human infections, however it may be an infectious agent especially in immunocompromised individuals. In this report, we present the first case of community acquired pneumonia caused by C. pauculus in a previously healthy newborn who was hospitalized in neonatal intensive care unit on postnatal day 16 because of respiratory distress.

  8. Draft Genome Sequence of Cupriavidus pauculus Strain KF709, a Biphenyl-Utilizing Bacterium Isolated from Biphenyl-Contaminated Soil.

    Science.gov (United States)

    Watanabe, Takahito; Yamazoe, Atsushi; Hosoyama, Akira; Fujihara, Hidehiko; Suenaga, Hikaru; Hirose, Jun; Futagami, Taiki; Goto, Masatoshi; Kimura, Nobutada; Furukawa, Kensuke

    2015-03-26

    We report the draft genome sequence of Cupriavidus pauculus strain KF709, which comprises 6,826,799 bp with 6,272 coding sequences. The strain KF709 utilizes biphenyl and degrades low-chlorinated biphenyls; however, it possesses fewer coding sequences involved in the degradation of aromatic compounds than other strains belonging to the Betaproteobacteria. Copyright © 2015 Watanabe et al.

  9. Draft Genome Sequence of Cupriavidus pauculus Strain KF709, a Biphenyl-Utilizing Bacterium Isolated from Biphenyl-Contaminated Soil

    OpenAIRE

    Watanabe, Takahito; Yamazoe, Atsushi; Hosoyama, Akira; Fujihara, Hidehiko; Suenaga, Hikaru; Hirose, Jun; Futagami, Taiki; Goto, Masatoshi; Kimura, Nobutada; Furukawa, Kensuke

    2015-01-01

    We report the draft genome sequence of Cupriavidus pauculus strain KF709, which comprises 6,826,799 bp with 6,272 coding sequences. The strain KF709 utilizes biphenyl and degrades low-chlorinated biphenyls; however, it possesses fewer coding sequences involved in the degradation of aromatic compounds than other strains belonging to the Betaproteobacteria.

  10. Pseudo-Outbreak of Cupriavidus pauculus Infection at an Outpatient Clinic Related to Rinsing Culturette Swabs in Tap Water▿

    Science.gov (United States)

    Balada-Llasat, Joan-Miquel; Elkins, Camille; Swyers, Lettie; Bannerman, Tammy; Pancholi, Preeti

    2010-01-01

    Cupriavidus pauculus is a water microorganism rarely isolated from clinical specimens. We describe a pseudo-outbreak in which multiple strains that were associated with moistening of culturette swabs with tap water were isolated from a single clinic before collecting the patient specimen. PMID:20444965

  11. Pseudo-outbreak of Cupriavidus pauculus infection at an outpatient clinic related to rinsing culturette swabs in tap water.

    Science.gov (United States)

    Balada-Llasat, Joan-Miquel; Elkins, Camille; Swyers, Lettie; Bannerman, Tammy; Pancholi, Preeti

    2010-07-01

    Cupriavidus pauculus is a water microorganism rarely isolated from clinical specimens. We describe a pseudo-outbreak in which multiple strains that were associated with moistening of culturette swabs with tap water were isolated from a single clinic before collecting the patient specimen.

  12. Pseudo-Outbreak of Cupriavidus pauculus Infection at an Outpatient Clinic Related to Rinsing Culturette Swabs in Tap Water▿

    OpenAIRE

    Balada-Llasat, Joan-Miquel; Elkins, Camille; Swyers, Lettie; Bannerman, Tammy; Pancholi, Preeti

    2010-01-01

    Cupriavidus pauculus is a water microorganism rarely isolated from clinical specimens. We describe a pseudo-outbreak in which multiple strains that were associated with moistening of culturette swabs with tap water were isolated from a single clinic before collecting the patient specimen.

  13. Aerobic biotransformation of 3-methylindole to ring cleavage products by Cupriavidus sp. strain KK10.

    Science.gov (United States)

    Fukuoka, Kimiko; Ozeki, Yasuhiro; Kanaly, Robert A

    2015-09-01

    3-Methylindole, also referred to as skatole, is a pollutant of environmental concern due to its persistence, mobility and potential health impacts. Petroleum refining, intensive livestock production and application of biosolids to agricultural lands result in releases of 3-methylindole to the environment. Even so, little is known about the aerobic biodegradation of 3-methylindole and comprehensive biotransformation pathways have not been established. Using glycerol as feedstock, the soil bacterium Cupriavidus sp. strain KK10 biodegraded 100 mg/L of 3-methylindole in 24 h. Cometabolic 3-methylindole biodegradation was confirmed by the identification of biotransformation products through liquid chromatography electrospray ionization tandem mass spectrometry analyses. In all, 14 3-methylindole biotransformation products were identified which revealed that biotransformation occurred through different pathways that included carbocyclic aromatic ring-fission of 3-methylindole to single-ring pyrrole carboxylic acids. This work provides first comprehensive evidence for the aerobic biotransformation mechanisms of 3-methylindole by a soil bacterium and expands our understanding of the biodegradative capabilities of members of the genus Cupriavidus towards heteroaromatic pollutants.

  14. Evaluation of the Biocidal Efficacy of Different Forms of Silver Against Cupriavidus (formerly Wautersia) Species Bacteria

    Science.gov (United States)

    Gazda, Daniel B.; Schultz, John R.; Wong, Wing; Algate, Michelle T.; Bryant, Becky; Castro, Victoria A.

    2009-01-01

    Contingency Water Containers (CWCs) are used to store potable and technical water that is transferred to the International Space Station (ISS) from the Shuttle orbiter vehicles. When CWCs are filled, water from the orbiter galley is passed through an ion exchange/activated carbon cartridge that removes the residual iodine biocide used on Shuttle before silver biocide is added. Removal of iodine and addition of silver is necessary to inhibit microbial growth inside CWCs and maintain compatibility with the water systems in the Russian segment of ISS. As part of nominal water transfer activities, crewmembers collect samples from several CWCs for postflight analysis. Results from the analysis of water transfer samples collected during the docked phases of STS-118/13A.1 and STS-120/10A showed that several of the CWCs contained up to 10(exp 4) CFU/mL of bacteria despite the fact that the silver concentrations in the CWCs were within acceptable limits. The samples contained pure cultures of a single bacteria, a Cupriavidus (formerly Wautersia) species that has been shown to be resistant to metallic biocides. As part of the investigation into the cause and remediation of the bacterial contamination in these CWCs, ground studies were initiated to evaluate the resistance of the Cupriavidus species to the silver biocides used on ISS and to determine the minimum effective concentration for the different forms of silver present in the biocides. The initial findings from those experiments are discussed herein.

  15. Biodegradation of pentachloronitrobenzene by Cupriavidus sp. YNS-85 and its potential for remediation of contaminated soils.

    Science.gov (United States)

    Teng, Ying; Wang, Xiaomi; Zhu, Ye; Chen, Wei; Christie, Peter; Li, Zhengao; Luo, Yongming

    2017-04-01

    Pentachloronitrobenzene (PCNB) is a toxic chlorinated nitroaromatic compound. However, only a few bacteria have been reported to be able to utilize PCNB. In the present study, one pentachloronitrobenzene (PCNB)-degrading bacterium, Cupriavidus sp. YNS-85, was isolated from a contaminated Panax notoginseng plantation. The strain co-metabolized 200 mg L -1 PCNB in aqueous solution with a removal rate of 73.8% after 5 days. The bacterium also degraded PCNB effectively under acid conditions (pH 4-6) and showed resistance to toxic trace elements (arsenic, copper, and cadmium). Its ability to utilize proposed PCNB intermediates as sole carbon sources was also confirmed. The soil microcosm experiment further demonstrated that bacterial bioaugmentation enhanced the removal of PCNB (37.8%) from soil and the accumulation of pentachloroaniline (89.3%) after 30 days. Soil enzyme activity and microbial community functional diversity were positively influenced after bioremediation. These findings indicate that Cupriavidus sp. YNS-85 may be a suitable inoculant for in situ bioremediation of PCNB-polluted sites, especially those with acid soils co-contaminated with heavy metal(loid)s.

  16. Uranium interaction with two multi-resistant environmental bacteria: Cupriavidus metallidurans CH34 and Rhodopseudomonas palustris.

    Science.gov (United States)

    Llorens, Isabelle; Untereiner, Guillaume; Jaillard, Danielle; Gouget, Barbara; Chapon, Virginie; Carriere, Marie

    2012-01-01

    Depending on speciation, U environmental contamination may be spread through the environment or inversely restrained to a limited area. Induction of U precipitation via biogenic or non-biogenic processes would reduce the dissemination of U contamination. To this aim U oxidation/reduction processes triggered by bacteria are presently intensively studied. Using X-ray absorption analysis, we describe in the present article the ability of Cupriavidus metallidurans CH34 and Rhodopseudomonas palustris, highly resistant to a variety of metals and metalloids or to organic pollutants, to withstand high concentrations of U and to immobilize it either through biosorption or through reduction to non-uraninite U(IV)-phosphate or U(IV)-carboxylate compounds. These bacterial strains are thus good candidates for U bioremediation strategies, particularly in the context of multi-pollutant or mixed-waste contaminations.

  17. Uranium Interaction with Two Multi-Resistant Environmental Bacteria: Cupriavidus metallidurans CH34 and Rhodopseudomonas palustris

    Science.gov (United States)

    Llorens, Isabelle; Untereiner, Guillaume; Jaillard, Danielle; Gouget, Barbara; Chapon, Virginie; Carriere, Marie

    2012-01-01

    Depending on speciation, U environmental contamination may be spread through the environment or inversely restrained to a limited area. Induction of U precipitation via biogenic or non-biogenic processes would reduce the dissemination of U contamination. To this aim U oxidation/reduction processes triggered by bacteria are presently intensively studied. Using X-ray absorption analysis, we describe in the present article the ability of Cupriavidus metallidurans CH34 and Rhodopseudomonas palustris, highly resistant to a variety of metals and metalloids or to organic pollutants, to withstand high concentrations of U and to immobilize it either through biosorption or through reduction to non-uraninite U(IV)-phosphate or U(IV)-carboxylate compounds. These bacterial strains are thus good candidates for U bioremediation strategies, particularly in the context of multi-pollutant or mixed-waste contaminations. PMID:23251623

  18. From organic pollutants to bioplastics: insights into the bioremediation of aromatic compounds by Cupriavidus necator.

    Science.gov (United States)

    Berezina, Nathalie; Yada, Bopha; Lefebvre, Rodrigue

    2015-01-25

    Organic pollution by aromatic compounds is of increasing concern to our environment. Therefore, the transformation of aromatic pollutants into valuable aliphatic and biodegradable bioplastics was studied. Since benzoic acid was found to be the key compound for such bioremediation processes, its transformation, and metabolic pathways of digestion, by Cupriavidus necator were specifically analysed. It was found that the degradation of aromatic compounds follows the 2,3-dioxygenase pathway in this strain and that the batch transformations of benzoic acid with either fresh or adapted cells were limited to an initial concentration of 2.5 g/L of pollutant. The repeated fed-batch with partial withdrawal process, however, showed a 17.5-fold improvement, thus allowing the transformation of a total of 43.7 g/L in 12 weeks. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Genome Sequence Analysis of the Naphthenic Acid Degrading and Metal Resistant Bacterium Cupriavidus gilardii CR3.

    Directory of Open Access Journals (Sweden)

    Xiaoyu Wang

    Full Text Available Cupriavidus sp. are generally heavy metal tolerant bacteria with the ability to degrade a variety of aromatic hydrocarbon compounds, although the degradation pathways and substrate versatilities remain largely unknown. Here we studied the bacterium Cupriavidus gilardii strain CR3, which was isolated from a natural asphalt deposit, and which was shown to utilize naphthenic acids as a sole carbon source. Genome sequencing of C. gilardii CR3 was carried out to elucidate possible mechanisms for the naphthenic acid biodegradation. The genome of C. gilardii CR3 was composed of two circular chromosomes chr1 and chr2 of respectively 3,539,530 bp and 2,039,213 bp in size. The genome for strain CR3 encoded 4,502 putative protein-coding genes, 59 tRNA genes, and many other non-coding genes. Many genes were associated with xenobiotic biodegradation and metal resistance functions. Pathway prediction for degradation of cyclohexanecarboxylic acid, a representative naphthenic acid, suggested that naphthenic acid undergoes initial ring-cleavage, after which the ring fission products can be degraded via several plausible degradation pathways including a mechanism similar to that used for fatty acid oxidation. The final metabolic products of these pathways are unstable or volatile compounds that were not toxic to CR3. Strain CR3 was also shown to have tolerance to at least 10 heavy metals, which was mainly achieved by self-detoxification through ion efflux, metal-complexation and metal-reduction, and a powerful DNA self-repair mechanism. Our genomic analysis suggests that CR3 is well adapted to survive the harsh environment in natural asphalts containing naphthenic acids and high concentrations of heavy metals.

  20. Pyruvic Oxime Nitrification and Copper and Nickel Resistance by a Cupriavidus pauculus, an Active Heterotrophic Nitrifier-Denitrifier

    OpenAIRE

    Ramirez, Miguel; Obrzydowski, Jennifer; Ayers, Mary; Virparia, Sonia; Wang, Meijing; Stefan, Kurtis; Linchangco, Richard; Castignetti, Domenic

    2014-01-01

    Heterotrophic nitrifiers synthesize nitrogenous gasses when nitrifying ammonium ion. A Cupriavidus pauculus, previously thought an Alcaligenes sp. and noted as an active heterotrophic nitrifier-denitrifier, was examined for its ability to produce nitrogen gas (N2) and nitrous oxide (N2O) while heterotrophically nitrifying the organic substrate pyruvic oxime [CH3–C(NOH)–COOH]. Neither N2 nor N2O were produced. Nucleotide and phylogenetic analyses indicated that the organism is a member of a g...

  1. Pyruvic oxime nitrification and copper and nickel resistance by a Cupriavidus pauculus, an active heterotrophic nitrifier-denitrifier.

    Science.gov (United States)

    Ramirez, Miguel; Obrzydowski, Jennifer; Ayers, Mary; Virparia, Sonia; Wang, Meijing; Stefan, Kurtis; Linchangco, Richard; Castignetti, Domenic

    2014-01-01

    Heterotrophic nitrifiers synthesize nitrogenous gasses when nitrifying ammonium ion. A Cupriavidus pauculus, previously thought an Alcaligenes sp. and noted as an active heterotrophic nitrifier-denitrifier, was examined for its ability to produce nitrogen gas (N2) and nitrous oxide (N2O) while heterotrophically nitrifying the organic substrate pyruvic oxime [CH3-C(NOH)-COOH]. Neither N2 nor N2O were produced. Nucleotide and phylogenetic analyses indicated that the organism is a member of a genus (Cupriavidus) known for its resistance to metals and its metabolism of xenobiotics. The microbe (a Cupriavidus pauculus designated as C. pauculus strain UM1) was examined for its ability to perform heterotrophic nitrification in the presence of Cu(2+) and Ni(2+) and to metabolize the xenobiotic phenol. The bacterium heterotrophically nitrified well when either 1 mM Cu(2+) or 0.5 mM Ni(2+) was present in either enriched or minimal medium. The organism also used phenol as a sole carbon source in either the presence or absence of 1 mM Cu(2+) or 0.5 mM Ni(2+). The ability of this isolate to perform a number of different metabolisms, its noteworthy resistance to copper and nickel, and its potential use as a bioremediation agent are discussed.

  2. Characterization of a newly isolated highly effective 3,5,6-trichloro-2-pyridinol degrading strain Cupriavidus pauculus P2.

    Science.gov (United States)

    Cao, Li; Liu, Hongming; Zhang, Hao; Huang, Ke; Gu, Tao; Ni, Haiyan; Hong, Qing; Li, Shunpeng

    2012-09-01

    A bacterial strain P2 capable of degrading 3,5,6-trichloro-2-pyridinol (TCP) was isolated and characterized. Phylogenetic analysis based on 16S rRNA gene sequence indicated that it belonged to the genus of Cupriavidus, because it showed the highest sequence similarity to Cupriavidus pauculus LMG 3413(T) (99.7 %) and DNA-DNA relatedness value between strain P2 and C. pauculus LMG 3413(T) was 76.8 %. In combination with morphological, physiological and biochemical characters, strain P2 was identified as C. pauculus. It could use TCP as the sole carbon source and energy source for its growth. It showed a high average degradation rate of 10 mg/L h in mineral salt medium amended with TCP (50-800 mg/L). During TCP degradation, chloridion was released into the medium in two obvious discontinuous stages. Along with this, two colorful metabolites were produced. Finally, the molarity of the total released chloridion was three times that of the initial TCP in the medium. This is the first report of TCP-degrading strain from the genus of Cupriavidus and the detection of two colorful metabolites during TCP degradation. Strain P2 might be a promising candidate for its application in the bioremediation of TCP-polluted environments.

  3. Pyruvic Oxime Nitrification and Copper and Nickel Resistance by a Cupriavidus pauculus, an Active Heterotrophic Nitrifier-Denitrifier

    Directory of Open Access Journals (Sweden)

    Miguel Ramirez

    2014-01-01

    Full Text Available Heterotrophic nitrifiers synthesize nitrogenous gasses when nitrifying ammonium ion. A Cupriavidus pauculus, previously thought an Alcaligenes sp. and noted as an active heterotrophic nitrifier-denitrifier, was examined for its ability to produce nitrogen gas (N2 and nitrous oxide (N2O while heterotrophically nitrifying the organic substrate pyruvic oxime [CH3–C(NOH–COOH]. Neither N2 nor N2O were produced. Nucleotide and phylogenetic analyses indicated that the organism is a member of a genus (Cupriavidus known for its resistance to metals and its metabolism of xenobiotics. The microbe (a Cupriavidus pauculus designated as C. pauculus strain UM1 was examined for its ability to perform heterotrophic nitrification in the presence of Cu2+ and Ni2+ and to metabolize the xenobiotic phenol. The bacterium heterotrophically nitrified well when either 1 mM Cu2+ or 0.5 mM Ni2+ was present in either enriched or minimal medium. The organism also used phenol as a sole carbon source in either the presence or absence of 1 mM Cu2+ or 0.5 mM Ni2+. The ability of this isolate to perform a number of different metabolisms, its noteworthy resistance to copper and nickel, and its potential use as a bioremediation agent are discussed.

  4. Cupriavidus malaysiensis sp. nov., a novel poly(3-hydroxybutyrate-co-4-hydroxybutyrate) accumulating bacterium isolated from the Malaysian environment.

    Science.gov (United States)

    Ramachandran, Hema; Shafie, Nur Asilla Hani; Sudesh, Kumar; Azizan, Mohamad Noor; Majid, Mohamad Isa Abdul; Amirul, Al-Ashraf Abdullah

    2018-03-01

    Bacterial classification on the basis of a polyphasic approach was conducted on three poly(3 hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] accumulating bacterial strains that were isolated from samples collected from Malaysian environments; Kulim Lake, Sg. Pinang river and Sg. Manik paddy field. The Gram-negative, rod-shaped, motile, non-sporulating and non-fermenting bacteria were shown to belong to the genus Cupriavidus of the Betaproteobacteria on the basis of their 16S rRNA gene sequence analyses. The sequence similarity value with their near phylogenetic neighbour, Cupriavidus pauculus LMG3413 T , was 98.5%. However, the DNA-DNA hybridization values (8-58%) and ribotyping analysis both enabled these strains to be differentiated from related Cupriavidus species with validly published names. The RiboPrint patterns of the three strains also revealed that the strains were genetically related even though they displayed a clonal diversity. The major cellular fatty acids detected in these strains included C15:0 ISO 2OH/C16:1 ω7c, hexadecanoic (16:0) and cis-11-octadecenoic (C18:1 ω7c). Their G+C contents ranged from 68.0  to 68.6 mol%, and their major isoprenoid quinone was Ubiquinone Q-8. Of these three strains, only strain USMAHM13 (= DSM 25816 = KCTC 32390) was discovered to exhibit yellow pigmentation that is characteristic of the carotenoid family. Their assembled genomes also showed that the three strains were not identical in terms of their genome sizes that were 7.82, 7.95 and 8.70 Mb for strains USMAHM13, USMAA1020 and USMAA2-4, respectively, which are slightly larger than that of Cupriavidus necator H16 (7.42 Mb). The average nucleotide identity (ANI) results indicated that the strains were genetically related and the genome pairs belong to the same species. On the basis of the results obtained in this study, the three strains are considered to represent a novel species for which the name Cupriavidus malaysiensis sp. nov. is proposed. The

  5. EXTRAÇÃO DE POLI(3-HIDROXIBUTIRATO, PRODUZIDO POR Cupriavidus necator, COM CARBONATO DE PROPILENO

    Directory of Open Access Journals (Sweden)

    Luci K. M. Quines

    2015-02-01

    Full Text Available The environmental impact of plastic waste has attracted worldwide attention. Amid the current context of increasing concern for the environment, biodegradable plastics have been widely studied as a replacement for synthetic plastics. Poly(3-hydroxybutyrate (P(3HB is a biopolymer stored as an intracellular energy and reserve source in many microorganisms. Because it is an intracellular product, P(3HB must be extracted from the cells at the end of the culture. The purpose of this study was to investigate the effect of extraction time, heating temperature, first standing time (after filtration and extraction, second standing time (after P(3HB precipitation and solvent amount, during the process of extracting P(3HB from Cupriavidus necator DSM 545, using propylene carbonate as solvent. The extraction kinetic of P(3HB with propylene carbonate from thermally treated biomass was evaluated at different temperatures. The physical properties of the P(3HB obtained were also evaluated. In this case, P(3HB obtained at optimal conditions of recovery (98% and purity (99% was used. Results showed that temperature was the most important factor in these responses for the range of values studied (110-150 ºC.

  6. Acid pretreatment and enzymatic saccharification of brown seaweed for polyhydroxybutyrate (PHB) production using Cupriavidus necator.

    Science.gov (United States)

    Azizi, Nahid; Najafpour, Ghasem; Younesi, Habibollah

    2017-08-01

    The brown seaweed Sargassum sp. was used as a feedstock to produce polyhydroxybutyarte (PHB) using Cupriavidus necator PTCC 1615. In order to release monomeric sugars, dilute acid hydrolysis of Sargassum sp. biomass was followed by enzymatic saccharification. In addition, the effect of different nitrogen sources was evaluated for PHB production. The fermentation of hydrolysate with the ammonium sulfate as selected nitrogen source resulted PHB yield of 0.54±0.01g/g reducing sugar. Then, NaCl was used as external stress factor which was added to the media. Addition of 8g/L NaCl had a positive impact on high PHB yield of 0.74±0.01g/g reducing sugar. Increasing trend of NaCl concentration to 16g/L was found to inhibit the production of PHB. Based on obtained results using 20g/L of reducing sugar, at desired condition the highest cell dry weight and PHB concentrations were 5.36±0.22 and 3.93±0.24g/L, respectively. The findings of this study reveal that Sargassum sp. is a promising feedstock for biopolymer production. The characteristics of produced PHB were analyzed by FTIR, differential scanning calorimetry and 1 H NMR. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Unveiling the biotransformation mechanism of indole in a Cupriavidus sp. strain.

    Science.gov (United States)

    Qu, Yuanyuan; Ma, Qiao; Liu, Ziyan; Wang, Weiwei; Tang, Hongzhi; Zhou, Jiti; Xu, Ping

    2017-12-01

    Indole, an important signaling molecule as well as a typical N-heterocyclic aromatic pollutant, is widespread in nature. However, the biotransformation mechanisms of indole are still poorly studied. Here, we sought to unlock the genetic determinants of indole biotransformation in strain Cupriavidus sp. SHE based on genomics, proteomics and functional studies. A total of 177 proteins were notably altered (118 up- and 59 downregulated) in cells grown in indole mineral salt medium when compared with that in sodium citrate medium. RT-qPCR and gene knockout assays demonstrated that an indole oxygenase gene cluster was responsible for the indole upstream metabolism. A functional indole oxygenase, termed IndA, was identified in the cluster, and its catalytic efficiency was higher than those of previously reported indole oxidation enzymes. Furthermore, the indole downstream metabolism was found to proceed via the atypical CoA-thioester pathway rather than conventional gentisate and salicylate pathways. This unusual pathway was catalyzed by a conserved 2-aminobenzoyl-CoA gene cluster, among which the 2-aminobenzoyl-CoA ligase initiated anthranilate transformation. This study unveils the genetic determinants of indole biotransformation and will provide new insights into our understanding of indole biodegradation in natural environments and its functional studies. © 2017 John Wiley & Sons Ltd.

  8. Inventorying the molecular potential of Cupriavidus and Ralstonia strains surviving harsh space-related environments

    Science.gov (United States)

    Mijnendonckx, Kristel; van Houdt, Rob; Provoost, Ann; Bossus, Albert; Ott, C. Mark; Venkateswaran, Kasthuri; Leys, Natalie

    The craving of modern man to explore life beyond earth presents a lot of challenges. The control of microbial contamination of the confined manned spacecraft is an important aspect that has to be taken into account in this journey. Because the human body contains a huge amount of microorganisms, the crew itself is the most important contamination source. But contamination can also originate from residing environmental microorganisms or from materials that are supplied from the Earth. These microbial contaminations can cause problems for the astronauts -well documented to have a decreased immunity -and the infrastructure of the space station. In this study, 14 different Cupriavidus metallidurans and Ralstonia pickettii strains, isolated from such space-related environments, where characterised in detail. These unique strains were isolated from drinking water that returned from ISS (3), from the cooling water system of the American ISS segment (4), from a swab sample of the Mars Odyssey Orbitor surface prior to flight (4), and from an air sample taken in the space assembly facility PHSF during Mars exploration Rover assembly (3). Their resistance to heavy metals and antibiotics was screened. The C. metallidurans isolates were more resistant to Zn2+ and Hg+ but more sensitive to Ni2+ than the R. pickettii strains. The MIC values for Cu2+ ranged from 1,5mM to 12mM, for Co2+ from 1,58mM to 12,63mM and for Cd2+ from 0,25mM to 1mM. For Ni2+ , the MIC values were between 2 and 8mM, except for the strain C. metallidurans IV (0502478) that was able to grow on Ni+2 concentrations up to 48mM. A metal of special interest was Ag+ because it is used to sanitize ISS drinking water. The strains isolated from air and surface samples showed a MIC value ranging from 0,35µM to 4µM. The isolates from the water samples had MIC values from 0,3µM to 2µM, which is lower than (or comparable with) the lowest limit of the silver concentration used in the ISS (1,9µM -4,6µM). However, all

  9. Increasing polyhydroxyalkanoate (PHA) yields from Cupriavidus necator by using filtered digestate liquors.

    Science.gov (United States)

    Passanha, Pearl; Esteves, Sandra R; Kedia, Gopal; Dinsdale, Richard M; Guwy, Alan J

    2013-11-01

    The production of polyhydroxyalkanoates (PHAs) using digestate liquor as culture media is a novel application to extend the existing uses of digestates. In this study, two micro-filtered digestates (0.22 μm) were evaluated as a source of complex culture media for the production of PHA by Cupriavidus necator as compared to a conventional media. Culture media using a mixture of micro-filtered liquors from food waste and from wheat feed digesters showed a maximum PHA accumulation of 12.29 g/l PHA, with 90% cell dry weight and a yield of 0.48 g PHA/g VFA consumed, the highest reported to date for C. necator studies. From the analysis of the starting and residual media, it was concluded that ammonia, potassium, magnesium, sulfate and phosphate provided in the digestate liquors were vital for the initial growth of C. necator whereas copper, iron and nickel may have played a significant role in PHA accumulation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Furfural reduction mechanism of a zinc-dependent alcohol dehydrogenase from Cupriavidus necator JMP134

    Science.gov (United States)

    Kang, ChulHee; Hayes, Robert; Sanchez, Emiliano J.; Webb, Brian N.; Li, Qunrui; Hooper, Travis; Nissen, Mark S.; Xun, Luying

    2012-01-01

    Summary FurX is a tetrameric Zn-dependent alcohol dehydrogenase (ADH) from Cupriavidus necator JMP134. The enzyme rapidly reduces furfural with NADH as the reducing power. For the first time among characterized ADHs, the high-resolution structures of all reaction steps were obtained in a time-resolved manner, thereby illustrating the complete catalytic events of NADH-dependent reduction of furfural and the dynamic Zn2+ coordination among Glu66, water, substrate and product. In the fully closed conformation of the NADH complex, the catalytic turnover proved faster than observed for the partially closed conformation due to an effective proton transfer network. The domain motion triggered by NAD(H) association/dissociation appeared to facilitate dynamic interchanges in Zn2+ coordination with substrate and product molecules, ultimately increasing the enzymatic turnover rate. NAD+ dissociation appeared to be a slow process, involving multiple steps in concert with a domain opening and reconfiguration of Glu66. This agrees with the report that the cofactor is not dissociated from FurX during ethanol-dependent reduction of furfural, in which ethanol reduces NAD+ to NADH that is subsequently used for furfural reduction. PMID:22081946

  11. Cupriavidus necator JMP134 rapidly reduces furfural with a Zn-dependent alcohol dehydrogenase.

    Science.gov (United States)

    Li, Qunrui; Metthew Lam, L K; Xun, Luying

    2011-11-01

    Ethanol is a renewable biofuel, and it can be produced from lignocellulosic biomass. The biomass is usually converted to hydrolysates that consist of sugar and sugar derivatives, such as furfural. Yeast ferments sugar to ethanol, but furfural higher than 3 mM is inhibitory. It can take several days for yeast cells to reduce furfural to non-inhibitory furfuryl alcohol before producing ethanol. Bioreduction of furfural to furfuryl alcohol before fermentation may relieve yeast from furfural toxicity. We observed that Cupriavidus necator JMP134, a strict aerobe, rapidly reduced 17 mM furfural to less than 3 mM within 14 min with cell turbidity of 1.0 at 600 nm at 50°C. The rapid reduction consumed ethanol. The "furfural reductase" (FurX) was purified, and it oxidized ethanol to acetaldehyde and reduced furfural to furfuryl alcohol with NAD(+) as the cofactor. The protein was identified with mass spectrometry fingerprinting to be a hypothetical protein belonging to Zn-dependent alcohol dehydrogenase family. The furX-inactivation mutant of C. necator JMP134 lost the ability to rapidly reduce furfural, and Escherichia coli producing recombinant FurX gained the ability. Thus, an alcohol dehydrogenase enabled bacteria to rapidly reduce furfural with ethanol as the reducing power.

  12. Pseudomonas, Pantoea and Cupriavidus isolates induce calcium carbonate precipitation for biorestoration of ornamental stone.

    Science.gov (United States)

    Daskalakis, M I; Magoulas, A; Kotoulas, G; Catsikis, I; Bakolas, A; Karageorgis, A P; Mavridou, A; Doulia, D; Rigas, F

    2013-08-01

    Bacterially induced calcium carbonate precipitation from various isolates was investigated aiming at developing an environmentally friendly technique for ornamental stone protection and restoration. Micro-organisms isolated from stone samples and identified using 16S rDNA and biochemical tests promoted calcium carbonate precipitation in solid and novel liquid growth media. Biomineral morphology was studied on marble samples with scanning electron microscopy. Most isolates demonstrated specimen weight increase, covering partially or even completely the marble surfaces mainly with vaterite. The conditions under which vaterite precipitated and its stability throughout the experimental runs are presented. A growth medium that facilitated bacterial growth of different species and promoted biomineralization was formulated. Most isolates induced biomineralization of CaCO3 . Micro-organisms may actually be a milestone in the investigation of vaterite formation facilitating our understanding of geomicrobiological interactions. Pseudomonas, Pantoea and Cupriavidus strains could be candidates for bioconsolidation of ornamental stone protection. Characterization of biomineralization capacity of different bacterial species improves understanding of the bacterially induced mineralization processes and enriches the list of candidates for biorestoration applications. Knowledge of biomineral morphology assists in differentiating mineral from biologically induced precipitates. © 2013 The Society for Applied Microbiology.

  13. Cupriavidus metallidurans biomineralization ability and its application as a bioconsolidation enhancer for ornamental marble stone.

    Science.gov (United States)

    Daskalakis, Markos I; Magoulas, Antonis; Kotoulas, Georgios; Katsikis, Ioannis; Bakolas, Asterios; Karageorgis, Aristomenis P; Mavridou, Athena; Doulia, Danae; Rigas, Fotis

    2014-08-01

    Bacterially induced calcium carbonate precipitation of a Cupriavidus metallidurans isolate was investigated to develop an environmentally friendly method for restoration and preservation of ornamental stones. Biomineralization performance was carried out in a growth medium via a Design of Experiments (DoE) approach using, as design factors, the temperature, growth medium concentration, and inoculum concentration. The optimum conditions were determined with the aid of consecutive experiments based on response surface methodology (RSM) and were successfully validated thereafter. Statistical analysis can be utilized as a tool for screening bacterial bioprecipitation as it considerably reduced the experimental time and effort needed for bacterial evaluation. Analytical methods provided an insight to the biomineral characteristics, and sonication tests proved that our isolate could create a solid new layer of vaterite on marble substrate withstanding sonication forces. C. metallidurans ACA-DC 4073 provided a compact vaterite layer on the marble substrate with morphological characteristics that assisted in its differentiation. The latter proved valuable during spraying minimum amount of inoculated media on marble substrate under conditions close to an in situ application. A sufficient and clearly distinguishable layer was identified.

  14. Low frequency sonic waves assisted cloud point extraction of polyhydroxyalkanoate from Cupriavidus necator.

    Science.gov (United States)

    Murugesan, Sivananth; Iyyaswami, Regupathi

    2017-08-15

    Low frequency sonic waves, less than 10kHz were introduced to assist cloud point extraction of polyhydroxyalkanoate from Cupriavidus necator present within the crude broth. Process parameters including surfactant system variables and sonication parameters were studied for their effect on extraction efficiency. Introduction of low frequency sonic waves assists in the dissolution of microbial cell wall by the surfactant micelles and release of cellular content, polyhydroxyalkanoate granules released were encapsulated by the micelle core which was confirmed by crotonic acid assay. In addition, sonic waves resulted in the separation of homogeneous surfactant and broth mixture into two distinct phases, top aqueous phase and polyhydroxyalkanoate enriched bottom surfactant rich phase. Mixed surfactant systems showed higher extraction efficiency compared to that of individual Triton X-100 concentrations, owing to increase in the hydrophobicity of the micellar core and its interaction with polyhydroxyalkanoate. Addition of salts to the mixed surfactant system induces screening of charged surfactant head groups and reduces inter-micellar repulsion, presence of ammonium ions lead to electrostatic repulsion and weaker cation sodium enhances the formation of micellar network. Addition of polyethylene glycol 8000 resulted in increasing interaction with the surfactant tails of the micelle core there by reducing the purity of polyhydroxyalkanoate. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Production and optimization of polyhydroxyalkanoates from non-edible Calophyllum inophyllum oil using Cupriavidus necator.

    Science.gov (United States)

    Arumugam, A; Senthamizhan, S G; Ponnusami, V; Sudalai, S

    2018-06-01

    Polyhydroxyalkanoates (PHA) are biodegradable polymers found in the cellular masses of a wide range of bacterial species and the demand for PHA is steadily growing. In this work we have produced PHA from a low-cost substrate, Calophyllum inophyllum oil, using Cupriavidus necator. Effects of various process parameters such as Oil concentration, Nitrogen source and inoculum size on the production of PHA were studied using Response Surface Methodology. A quadratic equation was used in the model to fit the experimental data. It was found that the model could satisfactorily predict the PHA yield (R 2 =99.17%). Linear, quadratic and interaction terms used in the model were found to be statistically significant. Maximum PHA yield of 10.6gL -1 was obtained under the optimized conditions of oil concentration - 17.5%, inoculum concentration - 50mL/L and nitrogen content - 1.125gL -1 , respectively. The product obtained was characterized using FTIR and NMR to confirm that it was PHA. The results demonstrate that C. inophyllum oil, a non-edible oil, can be potentially used as a low-cost substrate for the production of PHA. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Novel approach for productivity enhancement of polyhydroxyalkanoates (PHA) production by Cupriavidus necator DSM 545.

    Science.gov (United States)

    Berezina, Nathalie

    2013-01-25

    In the global context of increased concerns for our environment, the use of bioplastics as a replacement for existing petroleum-based polymers is an important challenge. Indeed, bioplastics hardly meet economical and technical constraints. One, of the most promising among currently studied bioplastics, is the polyhydroxyalkanoate (PHA). To circumvent the economical issue for this particular biopolymer one solution can be the enhancement of the overall productivity by the improvement of the nutritional medium of the microorganism producing the biopolymer. Thus, several nutrition media, supplemented or not with sodium glutamate, were tested for the growth and the PHA production by Cupriavidus necator DSM 545 strain. The most efficient for the biomass and the PHA production improvement were found to be the Luria broth (LB) and the Bonnarme's media, both supplemented with 10 g/L sodium glutamate. Hence the overall productivity was 33 times enhanced comparing to traditional cultivation methods. These results open a new route for the PHA production by C. necator which appears to be more suitable on a rich, or enriched, medium with no limiting factors. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Effect of limonene on the heterotrophic growth and polyhydroxybutyrate production by Cupriavidus necator H16.

    Science.gov (United States)

    Guzman Lagunes, F; Winterburn, J B

    2016-12-01

    The inhibitory effect of limonene on polyhydroxybutyrate (PHB) production in Cupriavidus necator H16 was studied. Firstly, results demonstrate the feasibility of using orange juicing waste (OJW) as a substrate for PHB production. An intracellular PHB content of 81.4% (w/w) was attained for a total dry matter concentration of 9.58gL -1 , when the OJW medium was used. Later, a mineral medium designed to mimic the nutrient levels found in the complex medium derived from OJW was used to study the effect of limonene on the production of PHB. Results showed a drop in specific growth rate (μ) of more than 50% when the initial limonene concentration was 2% (v/v) compared to the limonene free medium. This work highlights the importance of a limonene recovery stage prior to fermentation, to maintain levels below 1% (v/v) in the medium, adding value to the OJW and enhancing the fermentation process productivity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. PURIFICATION AND CHARACTERIZATION OF POLY-HYDROXYBUTYRATE (PHB IN CUPRIAVIDUS NECATOR

    Directory of Open Access Journals (Sweden)

    Sergio Leon De Rooy

    2010-06-01

    Full Text Available Purification and characterization of biodegradable plastic namely Polyhydroxybutyrate (PHB in Cupriavidus necator have been carried out. C. necator was grown on a Ramsay medium with fixed substrate conditions and optimized for time. Stepwise purification of PHB was carried out, by using hydrogen peroxide and chloroform. The effect of temperature, time, and hydrogen peroxide concentration on the purification were also evaluated. The extracted PHB was studied with XRD, FTIR and 1H-NMR and 13C-NMR to determine its structure and purity. Yield and crystallinity were also studied with HPLC and XRD, respectively. The results of the research showed that higher concentrations of hydrogen peroxide gave better yields, whereas higher temperatures and longer lysis times led to different results. Higher crystallinity was observed when purification temperatures were elevated, but higher hydrogen peroxide concentration and longer extraction time gave varying crystallinity. The highest yield ca 66.10 % DCW was reached by purification using H2O2 20 %, at 100 oC for 2 h. The results of   TGA analysis indicated that the purity of the PHB obtained was about 75 % and by using DSC, it was found that the PHB showed good thermal properties.   Keywords:  PHB, recovery, hydrogen peroxide, characterization

  19. Effect of sodium accumulation on heterotrophic growth and polyhydroxybutyrate (PHB) production by Cupriavidus necator.

    Science.gov (United States)

    Mozumder, Md Salatul Islam; Garcia-Gonzalez, Linsey; De Wever, Heleen; Volcke, Eveline I P

    2015-09-01

    This study evaluates the effect of sodium (Na(+)) concentration on the growth and PHB production by Cupriavidus necator. Both biomass growth and PHB production were inhibited by Na(+): biomass growth became zero at 8.9 g/L Na(+) concentration while PHB production was completely stopped at 10.5 g/L Na(+). A mathematical model for pure culture heterotrophic PHB production was set up to describe the Na(+) inhibition effect. The parameters related to Na(+) inhibition were estimated based on shake flask experiments. The accumulated Na(+) showed non-linear inhibition effect on biomass growth but linear inhibition effect on PHB production kinetics. Fed-batch experiments revealed that a high accumulation of Na(+) due to a prolonged growth phase, using NaOH for pH control, decreased the subsequent PHB production. The model was validated based on independent experimental data sets, showing a good agreement between experimental data and simulation results. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Accumulation of PHA granules in Cupriavidus necator as seen by confocal fluorescence microscopy.

    Science.gov (United States)

    Mravec, Filip; Obruca, Stanislav; Krzyzanek, Vladislav; Sedlacek, Petr; Hrubanova, Kamila; Samek, Ota; Kucera, Dan; Benesova, Pavla; Nebesarova, Jana

    2016-05-01

    Many bacteria are capable of accumulating intracellular granules of polyhydroxyalkanoates (PHA). In this work, we developed confocal microscopy analysis of bacterial cells to study changes in the diameters of cells as well as PHA granules during growth and PHA accumulation in the bacterium Cupriavidus necator H16 (formerly Ralstonia eutropha). The cell envelope was stained by DiD(®) fluorescent probe and PHA granules by Nile Red. Signals from both probes were separated based on their spectral and fluorescence life-time properties. During growth and PHA accumulation, bacterial cells increased their length but the width of the cells remained constant. The volume fraction of PHA granules in cells increased during PHA accumulation, nevertheless, its value did not exceed 40 vol. % regardless of the PHA weight content. It seems that bacterial cultures lengthen the cells in order to control the PHA volume portion. However, since similar changes in cell length were also observed in a PHA non-accumulating mutant, it seems that there is no direct control mechanism, which regulates the prolongation of the cells with respect to PHA granules volume. It is more likely that PHA biosynthesis and the length of cells are influenced by the same external stimuli such as nutrient limitation. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Conversion and assimilation of furfural and 5-(hydroxymethylfurfural by Pseudomonas putida KT2440

    Directory of Open Access Journals (Sweden)

    Michael T. Guarnieri

    2017-06-01

    Full Text Available The sugar dehydration products, furfural and 5-(hydroxymethylfurfural (HMF, are commonly formed during high-temperature processing of lignocellulose, most often in thermochemical pretreatment, liquefaction, or pyrolysis. Typically, these two aldehydes are considered major inhibitors in microbial conversion processes. Many microbes can convert these compounds to their less toxic, dead-end alcohol counterparts, furfuryl alcohol and 5-(hydroxymethylfurfuryl alcohol. Recently, the genes responsible for aerobic catabolism of furfural and HMF were discovered in Cupriavidus basilensis HMF14 to enable complete conversion of these compounds to the TCA cycle intermediate, 2-oxo-glutarate. In this work, we engineer the robust soil microbe, Pseudomonas putida KT2440, to utilize furfural and HMF as sole carbon and energy sources via complete genomic integration of the 12 kB hmf gene cluster previously reported from Burkholderia phytofirmans. The common intermediate, 2-furoic acid, is shown to be a bottleneck for both furfural and HMF metabolism. When cultured on biomass hydrolysate containing representative amounts of furfural and HMF from dilute-acid pretreatment, the engineered strain outperforms the wild type microbe in terms of reduced lag time and enhanced growth rates due to catabolism of furfural and HMF. Overall, this study demonstrates that an approach for biological conversion of furfural and HMF, relative to the typical production of dead-end alcohols, enables both enhanced carbon conversion and substantially improves tolerance to hydrolysate inhibitors. This approach should find general utility both in emerging aerobic processes for the production of fuels and chemicals from biomass-derived sugars and in the biological conversion of high-temperature biomass streams from liquefaction or pyrolysis where furfural and HMF are much more abundant than in biomass hydrolysates from pretreatment.

  2. Conversion and assimilation of furfural and 5-(hydroxymethyl)furfural by Pseudomonas putida KT2440.

    Science.gov (United States)

    Guarnieri, Michael T; Ann Franden, Mary; Johnson, Christopher W; Beckham, Gregg T

    2017-06-01

    The sugar dehydration products, furfural and 5-(hydroxymethyl)furfural (HMF), are commonly formed during high-temperature processing of lignocellulose, most often in thermochemical pretreatment, liquefaction, or pyrolysis. Typically, these two aldehydes are considered major inhibitors in microbial conversion processes. Many microbes can convert these compounds to their less toxic, dead-end alcohol counterparts, furfuryl alcohol and 5-(hydroxymethyl)furfuryl alcohol. Recently, the genes responsible for aerobic catabolism of furfural and HMF were discovered in Cupriavidus basilensis HMF14 to enable complete conversion of these compounds to the TCA cycle intermediate, 2-oxo-glutarate. In this work, we engineer the robust soil microbe, Pseudomonas putida KT2440, to utilize furfural and HMF as sole carbon and energy sources via complete genomic integration of the 12 kB hmf gene cluster previously reported from Burkholderia phytofirmans . The common intermediate, 2-furoic acid, is shown to be a bottleneck for both furfural and HMF metabolism. When cultured on biomass hydrolysate containing representative amounts of furfural and HMF from dilute-acid pretreatment, the engineered strain outperforms the wild type microbe in terms of reduced lag time and enhanced growth rates due to catabolism of furfural and HMF. Overall, this study demonstrates that an approach for biological conversion of furfural and HMF, relative to the typical production of dead-end alcohols, enables both enhanced carbon conversion and substantially improves tolerance to hydrolysate inhibitors. This approach should find general utility both in emerging aerobic processes for the production of fuels and chemicals from biomass-derived sugars and in the biological conversion of high-temperature biomass streams from liquefaction or pyrolysis where furfural and HMF are much more abundant than in biomass hydrolysates from pretreatment.

  3. Optimization of Cultural Conditions for Production of Extracellular Polymeric Substances (EPS) by Serpentine Rhizobacterium Cupriavidus pauculus KPS 201

    OpenAIRE

    Arundhati Pal; A. K. Paul

    2013-01-01

    Extracellular polymeric substances (EPS) are complex biopolymers produced by a wide array of microorganisms for protection against dessication, aggregation, adhesion, and expression of virulence. Growth associated production of EPS by Ni-resistant Cupriavidus pauculus KPS 201 was determined in batch culture using sodium gluconate as the sole carbon source. The optimum pH and temperature for EPS production were 6.5 and 25°C, respectively. Optimal EPS yield (118 μg/mL) was attained at 0.35% Na-...

  4. Screening and Evaluation of Polyhydroxybutyrate-Producing Strains from Indigenous Isolate Cupriavidus taiwanensis Strains

    Directory of Open Access Journals (Sweden)

    Om-Murugan Janarthanan

    2011-01-01

    Full Text Available Polyhydroxyalkanoate (PHA is a biodegradable material with many potential biomedical applications, including medical implants and drug delivery. This study developed a system for screening production strains in order to optimize PHA production in Cupriavidus taiwanensis 184, 185, 186, 187, 204, 208, 209 and Pseudomona oleovorans ATCC 29347. In this study, Sudan black B staining, Infrared (IR and Gas Chromatography (GC analysis indicated that the best strain for PHA synthesis is C. taiwanensis 184, which obtains polyhydroxybutyrate (PHB. Cultivation of C. taiwanensis 184 under a pH of 7.0, at 30 °C, and at an agitation rate of 200 rpm, obtained a PHB content of 10% and PHB production of 0.14 g/L. The carbon and nitrogen types selected for analysis of PHB production by C. taiwanensis 184 were gluconic acid and NH4Cl, respectively. Optimal carbon/nitrogen ratio for PHB production was also determined. This study demonstrated a PHB content of 58.81% and a PHB production of 2.44 g/L when the carbon/nitrogen ratio of 8/1 was selected for C. taiwanensis 184. A two‑stage fermentation strategy significantly enhanced PHB content and PHB production. Under a two-stage fermentation strategy with nutrient‑limited conditions, C. taiwanensis 184 obtained a PHB content of 72% and a PHB concentration of 7 g/L. Finally, experimental results confirmed that optimizing the growth medium and fermentation conditions for cultivating the indigenous C. taiwanensis 184 strain substantially elevated PHB content from 10% to 72% and PHB production from 0.14 g/L to 7 g/L, respectively.

  5. Connecting lignin-degradation pathway with pretreatment inhibitor sensitivity of Cupriavidus necator

    Directory of Open Access Journals (Sweden)

    Wei eWang

    2014-05-01

    Full Text Available To produce lignocellulosic biofuels economically, the complete release of monomers from the plant cell wall components, cellulose, hemicellulose and lignin, through pretreatment and hydrolysis (both enzymatic and chemical, and the efficient utilization of these monomers as carbon sources, is crucial. In addition, the identification and development of robust microbial biofuel production strains that can tolerate the toxic compounds generated during pretreatment and hydrolysis is also essential. In this work, Cupriavidus necator was selected due to its capabilities for utilizing lignin monomers and producing polyhydroxylbutyrate (PHB, a bioplastic as well as an advanced biofuel intermediate. We characterized the growth kinetics of C. necator in pretreated corn stover slurry as well as individually in the presence of 11 potentially toxic compounds in the saccharified slurry. We found that C. necator was sensitive to the saccharified slurry produced from dilute acid pretreated corn stover. Five out of 11 compounds within the slurry were characterized as toxic to C. necator, namely ammonium acetate, furfural, hydroxymethylfurfural (HMF, benzoic acid, and p-coumaric acid. Aldehydes (e.g., furfural and HMF were more toxic than the acetate and the lignin degradation products benzoic acid and p-coumaric acid; furfural was identified as the most toxic compound. Although toxic to C. necator at high concentration, ammonium acetate, benzoic acid, and p-coumaric acid could be utilized by C. necator with a stimulating effect on C. necator growth. Consequently, the lignin degradation pathway of C. necator was reconstructed based on genomic information and literature. The efficient conversion of intermediate catechol to downstream products of cis,cis-muconate or 2-hydroxymuconate-6-semialdehyde may help improve the robustness of C. necator to benzoic acid and p-coumaric acid as well as improve PHB productivity.

  6. Revisiting the single cell protein application of Cupriavidus necator H16 and recovering bioplastic granules simultaneously.

    Directory of Open Access Journals (Sweden)

    Balakrishnan Kunasundari

    Full Text Available Cupriavidus necator H16 (formerly known as Hydrogenomonas eutropha was famous as a potential single cell protein (SCP in the 1970s. The drawback however was the undesirably efficient accumulation of non-nutritive polyhydroxybutyrate (PHB storage compound in the cytoplasm of this bacterium. Eventually, competition from soy-based protein resulted in SCP not receiving much attention. Nevertheless, C. necator H16 remained in the limelight as a producer of PHB, which is a material that resembles commodity plastics such as polypropylene. PHB is a 100% biobased and biodegradable polyester. Although tremendous achievements have been attained in the past 3 decades in the efficient production of PHB, this bioplastic is still costly. One of the main problems has been the recovery of PHB from the cell cytoplasm. In this study, we showed for the first time that kilogram quantities of PHB can be easily recovered in the laboratory without the use of any solvents and chemicals, just by using the cells as SCP. In addition, the present study also demonstrated the safety and tolerability of animal model used, Sprague Dawley given lyophilized cells of C. necator H16. The test animals readily produced fecal pellets that were whitish in color, as would be expected of PHB granules. The pellets were determined to contain about 82-97 wt% PHB and possessed molecular mass of around 930 kg/mol. The PHB granules recovered biologically possessed similar molecular mass compared to chloroform extracted PHB [950 kg/mol]. This method now allows the production and purification of substantial quantities of PHB for various experimental trials. The method reported here is easy, does not require expensive instrumentation, scalable and does not involve extensive use of solvents and strong chemicals.

  7. High cell density strategy for poly(3-hydroxybutyrate production by Cupriavidus necator

    Directory of Open Access Journals (Sweden)

    J. L. Ienczak

    2011-12-01

    Full Text Available Poly(3-hydroxybutyrate (P(3HB is a carbon and intracellular storage source for different microorganisms and its production can achieve high productivities by means of high cell density cultures. The aim of this study was to propose a high cell density strategy for P(3HB production by Cupriavidus necator. The exponential growth phase demands an accurate control of the oxygen transfer system in the bioreactor, due to maximum specific growth rate (µXr, and, consequently, a maximum specific oxygen uptake rate (QO2, in addition to significant residual biomass (Xr growth in high cell density cultures. In this context, this work investigated the strategy for obtaining high cell density, with the inclusion of a linear growth phase for P(3HB production by C. necator in a fed-batch culture. The linear growth phase was included between the exponential growth phase and the P(3HB production phase as a strategy to reduce the specific growth rate (µXr and specific oxygen uptake rate (QO2, with constant residual biomass growth rate (d(V.Xr/dt = k = constant and linear increase of biomass. Three strategies of culture were performed. The results showed that a high residual biomass concentration (30 gXr.L-1 can be reached by the inclusion of the linear growth strategy and specific growth rates (µXr between 0.08 and 0.05 h-1, at the beginning of the production phase, are necessary to attain a high P(3HB productivity.

  8. Connecting Lignin-Degradation Pathway with Pre-Treatment Inhibitor Sensitivity of Cupriavidus necator

    Energy Technology Data Exchange (ETDEWEB)

    Wang, W. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Yang, S. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hunsinger, G. B. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Pienkos, P. T. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Johnson, D. K. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-05-27

    In order to produce lignocellulosic biofuels economically, the complete release of monomers from the plant cell wall components, cellulose, hemicellulose, and lignin, through pre-treatment and hydrolysis (both enzymatic and chemical), and the efficient utilization of these monomers as carbon sources, is crucial. In addition, the identification and development of robust microbial biofuel production strains that can tolerate the toxic compounds generated during pre-treatment and hydrolysis is also essential. In this work, Cupriavidus necator was selected due to its capabilities for utilizing lignin monomers and producing polyhydroxylbutyrate (PHB), a bioplastic as well as an advanced biofuel intermediate. We characterized the growth kinetics of C. necator in pre-treated corn stover slurry as well as individually in the pre-sence of 11 potentially toxic compounds in the saccharified slurry. We found that C. necator was sensitive to the saccharified slurry produced from dilute acid pre-treated corn stover. Five out of 11 compounds within the slurry were characterized as toxic to C. necator, namely ammonium acetate, furfural, hydroxymethylfurfural (HMF), benzoic acid, and p-coumaric acid. Aldehydes (e.g., furfural and HMF) were more toxic than the acetate and the lignin degradation products benzoic acid and p-coumaric acid; furfural was identified as the most toxic compound. Although toxic to C. necator at high concentration, ammonium acetate, benzoic acid, and p-coumaric acid could be utilized by C. necator with a stimulating effect on C. necator growth. Consequently, the lignin degradation pathway of C. necator was reconstructed based on genomic information and literature. The efficient conversion of intermediate catechol to downstream products of cis,cis-muconate or 2-hydroxymuconate-6-semialdehyde may help improve the robustness of C. necator to benzoic acid and p-coumaric acid as well as improve PHB productivity.

  9. Draft Genome Sequence of the Plant Growth-Promoting Cupriavidus gilardii Strain JZ4 Isolated from the Desert Plant Tribulus terrestris

    KAUST Repository

    Lafi, Feras Fawzi

    2016-07-28

    We isolated the plant endophytic bacterium Cupriavidus gilardii strain JZ4 from the roots of the desert plant Tribulus terrestris, collected from the Jizan region, Saudi Arabia. We report here the draft genome sequence of JZ4, together with several enzymes related to plant growth-promoting activity, environmental adaption, and antifungal activity.

  10. Draft Genome Sequence of the Plant Growth-Promoting Cupriavidus gilardii Strain JZ4 Isolated from the Desert Plant Tribulus terrestris

    KAUST Repository

    Lafi, Feras Fawzi; Bokhari, Ameerah; Alam, Intikhab; Bajic, Vladimir B.; Hirt, Heribert; Saad, Maged

    2016-01-01

    We isolated the plant endophytic bacterium Cupriavidus gilardii strain JZ4 from the roots of the desert plant Tribulus terrestris, collected from the Jizan region, Saudi Arabia. We report here the draft genome sequence of JZ4, together with several enzymes related to plant growth-promoting activity, environmental adaption, and antifungal activity.

  11. Correlation between Either Cupriavidus or Porphyromonas and Primary Pulmonary Tuberculosis Found by Analysing the Microbiota in Patients' Bronchoalveolar Lavage Fluid.

    Science.gov (United States)

    Zhou, Yuhua; Lin, Feishen; Cui, Zelin; Zhang, Xiangrong; Hu, Chunmei; Shen, Tian; Chen, Chunyan; Zhang, Xia; Guo, Xiaokui

    2015-01-01

    Pulmonary tuberculosis (TB) has gained attention in recent decades because of its rising incidence trend; simultaneously, increasing numbers of studies have identified the relationship between microbiota and chronic infectious diseases. In our work, we enrolled 32 patients with primary TB characterised by unilateral TB lesion formation diagnosed by chest radiographic exam. Bronchoalveolar lavage fluid was taken from both lungs. Twenty-four healthy people were chosen as controls. Pyrosequencing was performed on the V3 hypervariable region of 16S rDNA in all bacterial samples and used as a culture-independent method to describe the phylogenetic composition of the microbiota. Through pyrosequencing, 271,764 amplicons were detected in samples and analysed using tools in the Ribosomal Database Project (RDP) and bioinformatics. These analyses revealed significant differences in the microbiota in the lower respiratory tract (LRT) of TB patients compared with healthy controls; in contrast, the microbiota of intra/extra-TB lesions were similar. These results showed that the dominant bacterial genus in the LRT of TB patients was Cupriavidus and not Streptococcus, which resulted in a significant change in the microbiota in TB patients. The abundance of Mycobacteria and Porphyromonas significantly increased inside TB lesions when compared with non-lesion-containing contralateral lungs. From these data, it can be concluded that Cupriavidus plays an important role in TB's secondary infection and that in addition to Mycobacteria, Porphyromonas may also be a co-factor in lesion formation. The mechanisms underlying this connection warrant further research.

  12. [A case of ventilator-associated pneumonia caused by Cupriavidus pauculus].

    Science.gov (United States)

    Taşbakan, Mehmet Sezai; Yamazhan, Tansu; Aydemir, Söhret; Bacakoğlu, Feza

    2010-01-01

    Cupriavidus pauculus (formerly CDC Group IVc-2) is a non-fermentative, motile, gram-negative bacillus, rarely associated with human infections. It has been isolated from water, water from ultrafiltration systems and bottled mineral water. To date, 19 cases of bacteremia, two cases of peritonitis and one case of tenosynovitis associated with C. pauculus have been reported in English literature. In this paper, we report the first case of C. pauculus ventilator-associated pneumonia (VAP) in Turkey. A 47 years-old female with breast cancer was performed total mastectomy six years ago and received six cures of chemotherapy after surgery. The patient was hospitalized in medical oncology clinic with complaints of weight loss, nausea and vomiting for one year. Since she had problems of consiousness, dysphagia and pitosis, lumbar puncture was performed to rule out central nervous system infection or metastasis. Cryptococcal meningitis was diagnosed upon the examination of Indian-ink stained smear of cerebrospinal fluid and amphotericin B was initiated. On the 11th day of her follow up, she developed respiratory distress and was transferred to pulmonary intensive care and underwent invasive mechanical ventilator (IMV) therapy. On the 4th day of IMV; a new infiltration was detected on the upper zone of chest X-ray in addition to fever (38.3 degrees C) and intense endotracheal secretion. Therefore, bronchoscopic examination was performed and bronchoalveolar lavage and bronchoscope aspiration materials were obtained and cultivated. Bacteria grown at blood agar and EMB agar after 48 hours of incubation were stained as gram-negative bacilli and identified as C. pauculus by VITEK 2 compact system (bioMérieux Inc, USA). The strain was susceptible to ceftazidime, ciprofloxacin, imipenem, trimethoprim-sulfamethoxazole, piperacilin/tazobactam and resistant to amikacin. The case was considered as C. pauculus VAP and imipenem (500 mg, 4 x 1) for 14 days was initiated. Clinical and

  13. The components of the unique Zur regulon of Cupriavidus metallidurans mediate cytoplasmic zinc handling.

    Science.gov (United States)

    Bütof, Lucy; Schmidt-Vogler, Christopher; Herzberg, Martin; Große, Cornelia; Nies, Dietrich H

    2017-08-14

    Zinc is an essential trace element and at the same time it is toxic at high concentrations. In the beta-proteobacterium Cupriavidus metallidurans the highly efficient removal of surplus zinc from the periplasm is responsible for its outstanding metal resistance. Rather than having a typical Zur-dependent, high-affinity ATP-binding cassette transporter of the ABC protein superfamily for zinc uptake at low concentrations, C. metallidurans instead has the secondary zinc importer ZupT of the ZRT/IRT (ZIP) family. It is important to understand, therefore, how this zinc-resistant bacterium copes when it is exposed to low zinc concentrations. Members of the Zur regulon in C. metallidurans were identified by comparing the transcriptomes of a Δ zur mutant and its parent strain. The consensus sequence of the Zur-binding box was derived for the zupTp promoter-regulatory region using a truncation assay. The motif was used to predict possible Zur-boxes upstream of Zur regulon members. Binding of Zur to these boxes was confirmed. Two Zur-boxes upstream of the cobW 1 gene, encoding a putative zinc chaperone, proved to be required for complete repression of cobW 1 and its downstream genes in cells cultivated in mineral salts medium. A Zur box upstream of each of zur-cobW 2 , cobW 3 and zupT permitted low-expression level of these genes plus their up-regulation under zinc starvation conditions. This demonstrates a compartmentalization of zinc homeostasis in C. metallidurans with the periplasm being responsible for removal of surplus zinc and cytoplasmic components for management of zinc as an essential co-factor, with both compartments connected by ZupT. Importance Elucidating zinc homeostasis is necessary to understand both host-pathogen interactions and performance of free-living bacteria in their natural environment. Escherichia coli acquires zinc under low zinc concentrations by the Zur-controlled ZnuABC importer of the ABC superfamily, and this was also the paradigm for other

  14. Chicken feather hydrolysate as an inexpensive complex nitrogen source for PHA production by Cupriavidus necator on waste frying oils.

    Science.gov (United States)

    Benesova, P; Kucera, D; Marova, I; Obruca, S

    2017-08-01

    The chicken feather hydrolysate (FH) has been tested as a potential complex nitrogen source for the production of polyhydroxyalkanoates by Cupriavidus necator H16 when waste frying oil was used as a carbon source. The addition of FH into the mineral salt media with decreased inorganic nitrogen source concentration improved the yields of biomass and polyhydrohyalkanoates. The highest yields were achieved when 10 vol.% of FH prepared by microwave-assisted alkaline hydrolysis of 60 g l -1 feather was added. In this case, the poly(3-hydroxybutyrate) (PHB) yields were improved by more than about 50% as compared with control cultivation. A positive impact of FH was also observed for accumulation of copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) when sodium propionate was used as a precursor. The copolymer has superior processing and mechanical properties in comparison with PHB homopolymer. The application of FH eliminated the inhibitory effect of propionate and resulted in altered content of 3-hydroxyvalerate (3HV) in copolymer. Therefore, the hydrolysed feather can serve as an excellent complex source of nitrogen for the polyhydroxyalkanoates (PHA) production. Moreover, by the combination of two inexpensive types of waste, such as waste frying oil and feather hydrolysate, it is possible to produce PHA with substantially improved efficiency and sustainability. Millions of tons of feathers, important waste product of poultry-processing industry, are disposed off annually without any further benefits. Thus, there is an inevitable need for new technologies that enable ecologically and economically sensible processing of this waste. Herein, we report that alkali-hydrolysed feathers can be used as a complex nitrogen source considerably improving polyhydroxyalkanoates production on waste frying oil employing Cupriavidus necator. © 2017 The Society for Applied Microbiology.

  15. The complete genome sequence of Cupriavidus metallidurans strain CH34, a master survivalist in harsh and anthropogenic environments.

    Directory of Open Access Journals (Sweden)

    Paul J Janssen

    Full Text Available Many bacteria in the environment have adapted to the presence of toxic heavy metals. Over the last 30 years, this heavy metal tolerance was the subject of extensive research. The bacterium Cupriavidus metallidurans strain CH34, originally isolated by us in 1976 from a metal processing factory, is considered a major model organism in this field because it withstands milli-molar range concentrations of over 20 different heavy metal ions. This tolerance is mostly achieved by rapid ion efflux but also by metal-complexation and -reduction. We present here the full genome sequence of strain CH34 and the manual annotation of all its genes. The genome of C. metallidurans CH34 is composed of two large circular chromosomes CHR1 and CHR2 of, respectively, 3,928,089 bp and 2,580,084 bp, and two megaplasmids pMOL28 and pMOL30 of, respectively, 171,459 bp and 233,720 bp in size. At least 25 loci for heavy-metal resistance (HMR are distributed over the four replicons. Approximately 67% of the 6,717 coding sequences (CDSs present in the CH34 genome could be assigned a putative function, and 9.1% (611 genes appear to be unique to this strain. One out of five proteins is associated with either transport or transcription while the relay of environmental stimuli is governed by more than 600 signal transduction systems. The CH34 genome is most similar to the genomes of other Cupriavidus strains by correspondence between the respective CHR1 replicons but also displays similarity to the genomes of more distantly related species as a result of gene transfer and through the presence of large genomic islands. The presence of at least 57 IS elements and 19 transposons and the ability to take in and express foreign genes indicates a very dynamic and complex genome shaped by evolutionary forces. The genome data show that C. metallidurans CH34 is particularly well equipped to live in extreme conditions and anthropogenic environments that are rich in metals.

  16. Characterization of the Metabolically Modified Heavy Metal-Resistant Cupriavidus metallidurans Strain MSR33 Generated for Mercury Bioremediation

    Science.gov (United States)

    Rojas, Luis A.; Yáñez, Carolina; González, Myriam; Lobos, Soledad; Smalla, Kornelia; Seeger, Michael

    2011-01-01

    Background Mercury-polluted environments are often contaminated with other heavy metals. Therefore, bacteria with resistance to several heavy metals may be useful for bioremediation. Cupriavidus metallidurans CH34 is a model heavy metal-resistant bacterium, but possesses a low resistance to mercury compounds. Methodology/Principal Findings To improve inorganic and organic mercury resistance of strain CH34, the IncP-1β plasmid pTP6 that provides novel merB, merG genes and additional other mer genes was introduced into the bacterium by biparental mating. The transconjugant Cupriavidus metallidurans strain MSR33 was genetically and biochemically characterized. Strain MSR33 maintained stably the plasmid pTP6 over 70 generations under non-selective conditions. The organomercurial lyase protein MerB and the mercuric reductase MerA of strain MSR33 were synthesized in presence of Hg2+. The minimum inhibitory concentrations (mM) for strain MSR33 were: Hg2+, 0.12 and CH3Hg+, 0.08. The addition of Hg2+ (0.04 mM) at exponential phase had not an effect on the growth rate of strain MSR33. In contrast, after Hg2+ addition at exponential phase the parental strain CH34 showed an immediate cessation of cell growth. During exposure to Hg2+ no effects in the morphology of MSR33 cells were observed, whereas CH34 cells exposed to Hg2+ showed a fuzzy outer membrane. Bioremediation with strain MSR33 of two mercury-contaminated aqueous solutions was evaluated. Hg2+ (0.10 and 0.15 mM) was completely volatilized by strain MSR33 from the polluted waters in presence of thioglycolate (5 mM) after 2 h. Conclusions/Significance A broad-spectrum mercury-resistant strain MSR33 was generated by incorporation of plasmid pTP6 that was directly isolated from the environment into C. metallidurans CH34. Strain MSR33 is capable to remove mercury from polluted waters. This is the first study to use an IncP-1β plasmid directly isolated from the environment, to generate a novel and stable bacterial strain

  17. Characterization of the metabolically modified heavy metal-resistant Cupriavidus metallidurans strain MSR33 generated for mercury bioremediation.

    Directory of Open Access Journals (Sweden)

    Luis A Rojas

    Full Text Available BACKGROUND: Mercury-polluted environments are often contaminated with other heavy metals. Therefore, bacteria with resistance to several heavy metals may be useful for bioremediation. Cupriavidus metallidurans CH34 is a model heavy metal-resistant bacterium, but possesses a low resistance to mercury compounds. METHODOLOGY/PRINCIPAL FINDINGS: To improve inorganic and organic mercury resistance of strain CH34, the IncP-1β plasmid pTP6 that provides novel merB, merG genes and additional other mer genes was introduced into the bacterium by biparental mating. The transconjugant Cupriavidus metallidurans strain MSR33 was genetically and biochemically characterized. Strain MSR33 maintained stably the plasmid pTP6 over 70 generations under non-selective conditions. The organomercurial lyase protein MerB and the mercuric reductase MerA of strain MSR33 were synthesized in presence of Hg(2+. The minimum inhibitory concentrations (mM for strain MSR33 were: Hg(2+, 0.12 and CH(3Hg(+, 0.08. The addition of Hg(2+ (0.04 mM at exponential phase had not an effect on the growth rate of strain MSR33. In contrast, after Hg(2+ addition at exponential phase the parental strain CH34 showed an immediate cessation of cell growth. During exposure to Hg(2+ no effects in the morphology of MSR33 cells were observed, whereas CH34 cells exposed to Hg(2+ showed a fuzzy outer membrane. Bioremediation with strain MSR33 of two mercury-contaminated aqueous solutions was evaluated. Hg(2+ (0.10 and 0.15 mM was completely volatilized by strain MSR33 from the polluted waters in presence of thioglycolate (5 mM after 2 h. CONCLUSIONS/SIGNIFICANCE: A broad-spectrum mercury-resistant strain MSR33 was generated by incorporation of plasmid pTP6 that was directly isolated from the environment into C. metallidurans CH34. Strain MSR33 is capable to remove mercury from polluted waters. This is the first study to use an IncP-1β plasmid directly isolated from the environment, to generate a novel

  18. Probing the Kinetic Anabolism of Poly-Beta-Hydroxybutyrate in Cupriavidus necator H16 Using Single-Cell Raman Spectroscopy

    Directory of Open Access Journals (Sweden)

    Zhanhua Tao

    2016-08-01

    Full Text Available Poly-beta-hydroxybutyrate (PHB can be formed in large amounts in Cupriavidus necator and is important for the industrial production of biodegradable plastics. In this investigation, laser tweezers Raman spectroscopy (LTRS was used to characterize dynamic changes in PHB content—as well as in the contents of other common biomolecule—in C. necator during batch growth at both the population and single-cell levels. PHB accumulation began in the early stages of bacterial growth, and the maximum PHB production rate occurred in the early and middle exponential phases. The active biosynthesis of DNA, RNA, and proteins occurred in the lag and early exponential phases, whereas the levels of these molecules decreased continuously during the remaining fermentation process until the minimum values were reached. The PHB content inside single cells was relatively homogenous in the middle stage of fermentation; during the late growth stage, the variation in PHB levels between cells increased. In addition, bacterial cells in various growth phases could be clearly discriminated when principle component analysis was performed on the spectral data. These results suggest that LTRS is a valuable single-cell analysis tool that can provide more comprehensive information about the physiological state of a growing microbial population.

  19. Construction and use of a Cupriavidus necator H16 soluble hydrogenase promoter (PSH fusion to gfp (green fluorescent protein

    Directory of Open Access Journals (Sweden)

    Bat-Erdene Jugder

    2016-07-01

    Full Text Available Hydrogenases are metalloenzymes that reversibly catalyse the oxidation or production of molecular hydrogen (H2. Amongst a number of promising candidates for application in the oxidation of H2 is a soluble [Ni–Fe] uptake hydrogenase (SH produced by Cupriavidus necator H16. In the present study, molecular characterisation of the SH operon, responsible for functional SH synthesis, was investigated by developing a green fluorescent protein (GFP reporter system to characterise PSH promoter activity using several gene cloning approaches. A PSH promoter-gfp fusion was successfully constructed and inducible GFP expression driven by the PSH promoter under de-repressing conditions in heterotrophic growth media was demonstrated in the recombinant C. necator H16 cells. Here we report the first successful fluorescent reporter system to study PSH promoter activity in C. necator H16. The fusion construct allowed for the design of a simple screening assay to evaluate PSH activity. Furthermore, the constructed reporter system can serve as a model to develop a rapid fluorescent based reporter for subsequent small-scale process optimisation experiments for SH expression.

  20. Effective recovery of poly-β-hydroxybutyrate (PHB) biopolymer from Cupriavidus necator using a novel and environmentally friendly solvent system.

    Science.gov (United States)

    Fei, Tao; Cazeneuve, Stacy; Wen, Zhiyou; Wu, Lei; Wang, Tong

    2016-05-01

    This work demonstrates a significant advance in bioprocessing for a high-melting lipid polymer. A novel and environmental friendly solvent mixture, acetone/ethanol/propylene carbonate (A/E/P, 1:1:1 v/v/v) was identified for extracting poly-hydroxybutyrate (PHB), a high-value biopolymer, from Cupriavidus necator. A set of solubility curves of PHB in various solvents was established. PHB recovery of 85% and purity of 92% were obtained from defatted dry biomass (DDB) using A/E/P. This solvent mixture is compatible with water, and from non-defatted wet biomass, PHB recovery of 83% and purity of 90% were achieved. Water and hexane were evaluated as anti-solvents to assist PHB precipitation, and hexane improved recovery of PHB from biomass to 92% and the purity to 93%. A scale-up extraction and separation reactor was designed, built and successfully tested. Properties of PHB recovered were not significantly affected by the extraction solvent and conditions, as shown by average molecular weight (1.4 × 10(6) ) and melting point (175.2°C) not being different from PHB extracted using chloroform. Therefore, this biorenewable solvent system was effective and versatile for extracting PHB biopolymers. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:678-685, 2016. © 2016 American Institute of Chemical Engineers.

  1. Biosynthesis of poly(3-hydroxybutyrate) (PHB) by Cupriavidus necator H16 from jatropha oil as carbon source.

    Science.gov (United States)

    Batcha, Abeed Fatima Mohidin; Prasad, D M Reddy; Khan, Maksudur R; Abdullah, Hamidah

    2014-05-01

    Poly(3-hydroxybutyrate) (PHB) is a biodegradable polymer that can be synthesized through bacterial fermentation. In this study, Cupriavidus necator H16 is used to synthesize PHB by using Jatropha oil as its sole carbon source. Different variables mainly jatropha oil and urea concentrations, and agitation rate were investigated to determine the optimum condition for microbial fermentation in batch culture. Based on the results, the highest cell dry weight and PHB concentrations of 20.1 and 15.5 g/L, respectively, were obtained when 20 g/L of jatropha oil was used. Ethanol was used as external stress factor and the addition of 1.5 % ethanol at 38 h had a positive effect with a high PHB yield of 0.987 g PHB/g jatropha oil. The kinetic studies for cell growth rate and PHB production were conducted and the data were fitted with Logistic and Leudeking–Piret models. The rate constants were evaluated and the theoretical values were in accordance with the experimental data obtained

  2. Interactions of core–shell quantum dots with metal resistant bacterium Cupriavidus metallidurans: Consequences for Cu and Pb removal

    Energy Technology Data Exchange (ETDEWEB)

    Slaveykova, Vera I., E-mail: vera.slaveykova@unige.ch [Environmental Biogeochemistry and Ecotoxicology, Institute F.-A. Forel, Earth and Environment Science, Faculty of Sciences, University of Geneva, 10, route de Suisse, 1290 Versoix (Switzerland); Pinheiro, José Paulo [IBB/CBME, Department of Chemistry and Biochemistry, University of the Algarve, Gambelas Campus, 8005-139 Faro (Portugal); Floriani, Magali [IRSN/DEI/SECRE/LRE CEA Cadarache, 13115 Saint-Paul-Lez-Durance (France); Garcia, Miguel [School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Station 15, CH-1015 Lausanne (Switzerland)

    2013-10-15

    Highlights: • QDs associate with C. metallidurans in time and concentration dependent manner. • 12.9 nm size QDs adhere to the bacterial surface and enter the periplasmic space. • QDs bound significantly Cu and Pb. • QDs increase Cu and Pb content in C. metallidurans during short term exposure. -- Abstract: In the present study we address the interactions of carboxyl-CdSe/ZnS core/shell quantum dots (QDs), as a model of water dispersible engineered nanoparticles, and metal resistant bacteria Cupriavidus metallidurans, largely used in metal decontamination. The results demonstrate that QDs with average hydrodynamic size of 12.9 nm adhere to C. metallidurans. The percentage of bacterial cells displaying QD-fluorescence increased proportionally with contact time and QD concentration in bacterial medium demonstrating the association of QDs with the metal resistant bacteria. No evidence of QD internalization into bacterial cytoplasm was found by transmission electron microscopy with energy dispersive X-ray spectrometry, however QD clusters of sizes between 20 and 50 nm were observed on the bacterial surface and in the bacterial periplasmic compartment; observations consistent with the losses of membrane integrity induced by QDs. The presence of 20 nM QDs induced about 2-fold increase in Cu and Pb uptake fluxes by C. metallidurans exposed to 500 nM Pb or Cu, respectively. Overall, the results of this work suggest that when present in mixture with Cu and Pb, low levels of QDs originating from possible incidental release or QD disposal could increase metal accumulation in metal resistant bacterium.

  3. Biofilm vs. Planktonic Lifestyle: Consequences for Pesticide 2,4-D Metabolism by Cupriavidus necator JMP134

    Directory of Open Access Journals (Sweden)

    Thomas Z. Lerch

    2017-05-01

    Full Text Available The development of bacterial biofilms in natural environments may alter important functions, such as pollutant bioremediation by modifying both the degraders' physiology and/or interactions within the matrix. The present study focuses on the influence of biofilm formation on the metabolism of a pesticide, 2,4-dichlorophenoxyacetic acid (2,4-D, by Cupriavidus necator JMP134. Pure cultures were established in a liquid medium with 2,4-D as a sole carbon source with or without sand grains for 10 days. Bacterial numbers and 2,4-D concentrations in solution were followed by spectrophotometry, the respiration rate by gas chromatography and the surface colonization by electron microscopy. In addition, isotopic techniques coupled with Fatty Acid Methyl Ester (FAME profiling were used to determine possible metabolic changes. After only 3 days, approximately 80% of the cells were attached to the sand grains and microscopy images showed that the porous medium was totally clogged by the development of a biofilm. After 10 days, there was 25% less 2,4-D in the solution in samples with sand than in control samples. This difference was due to (1 a higher (+8% mineralization of 2,4-D by sessile bacteria and (2 a retention (15% of 2,4-D in the biofilm matrix. Besides, the amount of carbohydrates, presumably constituting the biofilm polysaccharides, increased by 63%. Compound-specific isotope analysis revealed that the FAME isotopic signature was less affected by the biofilm lifestyle than was the FAME composition. These results suggest that sessile bacteria differ more in their anabolism than in their catabolism compared to their planktonic counterparts. This study stresses the importance of considering interactions between microorganisms and their habitat when studying pollutant dynamics in porous media.

  4. Minimal Influence of [NiFe] Hydrogenase on Hydrogen Isotope Fractionation in H2-Oxidizing Cupriavidus necator

    Directory of Open Access Journals (Sweden)

    Brian J. Campbell

    2017-10-01

    Full Text Available Fatty acids produced by H2-metabolizing bacteria are sometimes observed to be more D-depleted than those of photoautotrophic organisms, a trait that has been suggested as diagnostic for chemoautotrophic bacteria. The biochemical reasons for such a depletion are not known, but are often assumed to involve the strong D-depletion of H2. Here, we cultivated the bacterium Cupriavidus necator H16 (formerly Ralstonia eutropha H16 under aerobic, H2-consuming, chemoautotrophic conditions and measured the isotopic compositions of its fatty acids. In parallel with the wild type, two mutants of this strain, each lacking one of two key hydrogenase enzymes, were also grown and measured. In all three strains, fractionations between fatty acids and water ranged from -173‰ to -235‰, and averaged -217‰, -196‰, and -226‰, respectively, for the wild type, SH- mutant, and MBH- mutant. There was a modest increase in δD as a result of loss of the soluble hydrogenase enzyme. Fractionation curves for all three strains were constructed by growing parallel cultures in waters with δDwater values of approximately -25‰, 520‰, and 1100‰. These curves indicate that at least 90% of the hydrogen in fatty acids is derived from water, not H2. Published details of the biochemistry of the soluble and membrane-bound hydrogenases confirm that these enzymes transfer electrons rather than intact hydride (H- ions, providing no direct mechanism to connect the isotopic composition of H2 to that of lipids. Multiple lines of evidence thus agree that in this organism, and presumably others like it, environmental H2 plays little or no direct role in controlling lipid δD values. The observed fractionations must instead result from isotope effects in the reduction of NAD(PH by reductases with flavin prosthetic groups, which transfer two electrons and acquire H+ (or D+ from solution. Parallels to NADPH reduction in photosynthesis may explain why D/H fractionations in C. necator

  5. Engineering Deinococcus radiodurans R1 for bioremediation of non radioactive and radioactive wastes facilitated by comparative genomics with Cupriavidus metallidurans CH34

    International Nuclear Information System (INIS)

    Badri, Hanene; Sghaier, Haitham; Barkallah, Insaf; Ben Salem, Issam; Wafa; Essouiss, Imen; Saied, Nadia; Saidi, M.; Gatri, Faten; Gatri, Maher; Boadabous, Abdellatifs; Leys, Natalie

    2009-01-01

    Deinococcus radiodurans R1 is a poly-extremophile for which a system of genetic transformation and manipulation has been developed and it is being engineered for in situ bioremediation of wastes particularly for cleanup of radioactive waste sites. In this study, additional attempts have been made to evaluate ''bioremediation determinants'' in the genome of D. radiodurans using a comparative-genomic approach with Cupriavidus metallidurans CH34, a multiple metal resistant bacterium. This resulted in the delineation of a set of ORFs that are common or peculiar to C. metallidurans and D. radiodurans. We identified 12 ORFs related to multidrug resistance efflux pumps as a special feature of C. metallidurans compared to D. radiodurans, which is the subject of further experimental work

  6. Comparison of chemical washing and physical cell-disruption approaches to assess the surface adsorption and internalization of cadmium by Cupriavidus metallidurans CH34

    Energy Technology Data Exchange (ETDEWEB)

    Desaunay, Aurélien; Martins, Jean M.F., E-mail: jean.martins@ujf-grenoble.fr

    2014-05-01

    Highlights: • Subcellular distribution of cadmium in Cupriavidus metallidurans CH34 cells. • Comparison of a chemical (EDTA washing) and a physical method (physical disruption). • EDTA washings strongly overestimated membrane-bound Cd concentrations. • The physical method revealed surprisingly over 80% of Cd internalization in the cells. • Metal biosorption by bacteria cannot be considered as a surface complexation process. - Abstract: Bacterial biosorption of heavy metals is often considered as a surface complexation process, without considering other retention compartments than cell walls. Although this approach gives a good description of the global biosorption process, it hardly permits the prediction of the fate of biosorbed metals in the environment. This study examines the subcellular distribution of cadmium (Cd) in the metal-tolerant bacterium Cupriavidus metallidurans CH34 through the comparison of an indirect chemical method (washing cells with EDTA) and a direct physical method (physical disruption of cells). The chemical washing approach presented strong experimental biases leading to the overestimation of washed amount of Cd, supposedly bound to cell membranes. On the contrary, the physical disruption approach gave reproducible and robust results of Cd subcellular distribution. Unexpectedly, these results showed that over 80% of passively biosorbed Cd is internalized in the cytoplasm. In disagreement with the common concept of surface complexation of metals onto bacteria the cell wall was poorly reactive to Cd. Our results indicate that metal sorption onto bacterial surfaces is only a first step in metal management by bacteria and open new perspectives on metal biosorption by bacteria in the environment, with implications for soil bioremediation or facilitated transport of metals by bacteria.

  7. Global changes in the proteome of Cupriavidus necator H16 during poly-(3-hydroxybutyrate) synthesis from various biodiesel by-product substrates.

    Science.gov (United States)

    Sharma, Parveen K; Fu, Jilagamazhi; Spicer, Victor; Krokhin, Oleg V; Cicek, Nazim; Sparling, Richard; Levin, David B

    2016-12-01

    Synthesis of poly-[3-hydroxybutyrate] (PHB) by Cupriavidus necator H16 in batch cultures was evaluated using three biodiesel-derived by-products as the sole carbon sources: waste glycerol (REG-80, refined to 80 % purity with negligible free fatty acids); glycerol bottom (REG-GB, with up to 65 % glycerol and 35 % free fatty acids), and free fatty acids (REG-FFA, with up to 75 % FFA and no glycerol). All the three substrates supported growth and PHB production by C. necator, with polymer accumulation ranging from 9 to 84 % cell dry weight (cdw), depending on the carbon source. To help understand these differences, proteomic analysis indicated that although C. necator H16 was able to accumulate PHB during growth on all three biodiesel by-products, no changes in the levels of PHB synthesis enzymes were observed. However, significant changes in the levels of expression were observed for two Phasin proteins involved with PHB accumulation, and for a number of gene products in the fatty acid β-oxidation pathway, the Glyoxylate Shunt, and the hydrogen (H2) synthesis pathways in C. necator cells cultured with different substrates. The glycerol transport protein (GlpF) was induced in REG-GB and REG-80 glycerol cultures only. Cupriavidus necator cells cultured with REG-GB and REG-FFA showed up-regulation of β-oxidation and Glyoxylate Shunt pathways proteins at 24 h pi, but H2 synthesis pathways enzymes were significantly down-regulated, compared with cells cultured with waste glycerol. Our data confirmed earlier observations of constitutive expression of PHB synthesis proteins, but further suggested that C. necator H16 cells growing on biodiesel-derived glycerol were under oxidative stress.

  8. Enhanced production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) copolymer and antimicrobial yellow pigmentation from Cupriavidus sp. USMAHM13 with antibiofilm capability.

    Science.gov (United States)

    Ismail, Iszatty; Gurusamy, Tana Poorani; Ramachandran, Hema; Al-Ashraf Amirul, Abdullah

    2017-04-21

    Antibiofilm polymers have the ability to inhibit bacterial biofilm formation, which is known to occur ubiquitously in the environment and pose risks of infection. In this study, production of P(3HB-co-4HB) copolymer and antimicrobial yellow pigment from Cupriavidus sp. USMAHM13 are enhanced through medium optimization. Before the improvement of yellow pigment production, screening for the best additional supplement was performed resulting in high-yield yellow pigmentation using yeast extract with optimum concentration of 2 g/L. Effects of different concentrations of 1,4-butanediol, ammonium acetate, and yeast extract were studied using central composite design. Under optimal conditions, 53 wt% of polyhydroxyalkanoate (PHA) content, 0.35 g/L of pigment concentration, and 5.87 g/L of residual biomass were achieved at 0.56 wt% C of 1,4-butanediol, 1.14 g/L of ammonium acetate, and 2 g/L of yeast extract. Antibiofilm tests revealed that the yellow pigment coated on P(3HB-co-4HB) copolymer had significant effect on the inhibition of bacteria proliferation and colonization from 6 hr onward reaching 100% inhibition by 12 hr, hence effectively inhibiting the biofilm formation.

  9. Swimming, swarming, twitching, and chemotactic responses of Cupriavidus metallidurans CH34 and Pseudomonas putida mt2 in the presence of cadmium.

    Science.gov (United States)

    Shamim, Saba; Rehman, Abdul; Qazi, Mahmood Hussain

    2014-04-01

    To use of microorganisms for bioremediation purposes, the study of their motility behavior toward metals is essential. In the present study, Cupriavidus metallidurans CH34 and Pseudomonas putida mt2 were used as cadmium (Cd)-resistant and -sensitive bacteria, respectively, to evaluate the effects of Cd on their motility behaviors. Potassium morpholinopropane sulfonate (MOPS) buffer was used to observe the motility behavior of both isolates. Movement of mt2 was less in MOPS buffer compared with CH34, likely reflecting the mono-flagellated nature of mt2 and the peritrichous nature of CH34. The swimming, swarming, twitching, and chemotaxis behaviors of mt2 were greater in the presence of glucose than that of Cd. mt2 exhibited negative motility behaviors when exposed to Cd, but the opposite effect was seen in CH34. Cd was found to be a chemorepellent for mt2 but a chemoattractant for CH34, suggesting that CH34 is a potential candidate for metal (Cd) bioremediation.

  10. Characterization of d-succinylase from Cupriavidus sp. P4-10-C and its application in d-amino acid synthesis.

    Science.gov (United States)

    Sumida, Yosuke; Iwai, Sachio; Nishiya, Yoshiaki; Kumagai, Shinya; Yamada, Toshihide; Azuma, Masayuki

    2018-03-01

    d-Amino acids are important building blocks for various compounds, such as pharmaceuticals and agrochemicals. A more cost-effective enzymatic method for d-amino acid production is needed in the industry. We improved a one-pot enzymatic method for d-amino acid production by the dynamic kinetic resolution of N-succinyl amino acids using two enzymes: d-succinylase (DSA) from Cupriavidus sp. P4-10-C, which hydrolyzes N-succinyl-d-amino acids enantioselectively to their corresponding d-amino acid, and N-succinyl amino acid racemase (NSAR, EC.4.2.1.113) from Geobacillus stearothermophilus NCA1503. In this study, DSA and NSAR were purified and their properties were investigated. The optimum temperature of DSA was 50°C and it was stable up to 55°C. The optimum pH of DSA and NSAR was around 7.5. In d-phenylalanine production, the optical purity of product was improved to 91.6% ee from the examination about enzyme concentration. Moreover, 100 mM N-succinyl-dl-tryptophan was converted to d-tryptophan at 81.8% yield with 94.7% ee. This enzymatic method could be useful for the industrial production of various d-amino acids. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  11. Cloud-point extraction of green-polymers from Cupriavidus necator lysate using thermoseparating-based aqueous two-phase extraction.

    Science.gov (United States)

    Leong, Yoong Kit; Lan, John Chi-Wei; Loh, Hwei-San; Ling, Tau Chuan; Ooi, Chien Wei; Show, Pau Loke

    2017-03-01

    Polyhydroxyalkanoates (PHAs), a class of renewable and biodegradable green polymers, have gained attraction as a potential substitute for the conventional plastics due to the increasing concern towards environmental pollution as well as the rapidly depleting petroleum reserve. Nevertheless, the high cost of downstream processing of PHA has been a bottleneck for the wide adoption of PHAs. Among the options of PHAs recovery techniques, aqueous two-phase extraction (ATPE) outshines the others by having the advantages of providing a mild environment for bioseparation, being green and non-toxic, the capability to handle a large operating volume and easily scaled-up. Utilizing unique properties of thermo-responsive polymer which has decreasing solubility in its aqueous solution as the temperature rises, cloud point extraction (CPE) is an ATPE technique that allows its phase-forming component to be recycled and reused. A thorough literature review has shown that this is the first time isolation and recovery of PHAs from Cupriavidus necator H16 via CPE was reported. The optimum condition for PHAs extraction (recovery yield of 94.8% and purification factor of 1.42 fold) was achieved under the conditions of 20 wt/wt % ethylene oxide-propylene oxide (EOPO) with molecular weight of 3900 g/mol and 10 mM of sodium chloride addition at thermoseparating temperature of 60°C with crude feedstock limit of 37.5 wt/wt %. Recycling and reutilization of EOPO 3900 can be done at least twice with satisfying yield and PF. CPE has been demonstrated as an effective technique for the extraction of PHAs from microbial crude culture. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  12. Mineralization of PCBs by the genetically modified strain Cupriavidus necator JMS34 and its application for bioremediation of PCBs in soil

    Energy Technology Data Exchange (ETDEWEB)

    Saavedra, Juan Matias; Acevedo, Francisca; Gonzalez, Myriam; Seeger, Michael [Universidad Tecnica Federico Santa Maria, Valparaiso (Chile). Lab. de Microbiologia Molecular y Biotecnologia

    2010-07-15

    Polychlorobiphenyls (PCBs) are classified as ''high-priority pollutants''. Diverse microorganisms are able to degrade PCBs. However, bacterial degradation of PCBs is generally incomplete, leading to the accumulation of chlorobenzoates (CBAs) as dead-end metabolites. To obtain a microorganism able to mineralize PCB congeners, the bph locus of Burkholderia xenovorans LB400, which encodes one of the most effective PCB degradation pathways, was incorporated into the genome of the CBA-degrading bacterium Cupriavidus necator JMP134-X3. The bph genes were transferred into strain JMP134-X3, using the mini-Tn5 transposon system and biparental mating. The genetically modified derivative, C. necator strain JMS34, had only one chromosomal insertion of bph locus, which was stable under nonselective conditions. This modified bacterium was able to grow on biphenyl, 3-CBA and 4-CBA, and degraded 3,5-CBA in the presence of m-toluate. The strain JMS34 mineralized 3-CB, 4-CB, 2,4{sup '}-CB, and 3,5-CB, without accumulation of CBAs. Bioaugmentation of PCB-polluted soils with C. necator strain JMS34 and with the native B. xenovorans LB400 was monitored. It is noteworthy that strain JMS34 degraded, in 1 week, 99% of 3-CB and 4-CB and approximately 80% of 2,4{sup '}-CB in nonsterile soil, as well as in sterile soil. Additionally, the bacterial count of strain JMS34 increased by almost two orders of magnitude in PCB-polluted nonsterile soil. In contrast, the presence of native microflora reduced the degradation of these PCBs by strain LB400 from 73% (sterile soil) to approximately 50% (nonsterile soil). This study contributes to the development of improved biocatalysts for remediation of PCB-contaminated environments. (orig.)

  13. Study of the Cupriavidus metallidurans CH34 resistance of selenite and selenate oxy-anions: accumulation, localisation and transformation of selenium

    International Nuclear Information System (INIS)

    Avoscan, L.

    2007-06-01

    Selenium is an essential trace element for the living organisms but it is very toxic at high concentration. Selenite and selenate oxides, soluble forms, highly toxic and bio-assimilable, are the most prevalent forms in the environment. Some soil micro-organisms play a dominant role and contribute to the natural cycle of selenium. Our study model, Cupriavidus (formerly Ralstonia) metallidurans CH34, a telluric bacterium characteristic of metal-contaminated biotopes, is known to resist selenite by reducing it into elemental selenium, an insoluble and less toxic form of selenium. In order to better understand the mechanisms of selenium reduction in the bacteria, three methods of speciation were combined (XAS (XANES and EXAFS), HPLC-ICP-MS and SDS-PAGEPIXE). They were completed by the direct quantification of selenium accumulated in the bacteria. Speciation analyses highlighted the existence of two mechanisms of reduction of selenium oxides in C. metallidurans CH34. Assimilation transforms selenite and selenate into organic selenium, identified as seleno-methionine and leads to its non-specific incorporation into bacterial proteins (presence of selenious proteins). Detoxication precipitates selenite in nano-particles of elemental selenium. This way of detoxication is not set up after an exposure to selenate although it is nevertheless possible to detect elemental selenium but in very small amount compared to the exposure of selenite. Seleno-diglutathion is detected in bacteria stressed by an exposure to selenate in medium limited in sulphate. Bacteria exposed to selenite accumulate 25 times more selenium than when they are exposed to selenate. The study of mutants resistant to selenite, which do not express the membrane protein DedA, showed that the accumulation of selenium after exposure to selenite is decreased compared with the wild strain meaning probable link between the transport of selenite and the DedA protein. Finally, selenate would use the sulphate permease

  14. The Impact of Space Flight on Survival and Interaction of Cupriavidus metallidurans CH34 with Basalt, a Volcanic Moon Analog Rock

    Directory of Open Access Journals (Sweden)

    Natalie Leys

    2017-04-01

    Full Text Available Microbe-mineral interactions have become of interest for space exploration as microorganisms could be used to biomine from extra-terrestrial material and extract elements useful as micronutrients in life support systems. This research aimed to identify the impact of space flight on the long-term survival of Cupriavidus metallidurans CH34 in mineral water and the interaction with basalt, a lunar-type rock in preparation for the ESA spaceflight experiment, BIOROCK. Therefore, C. metallidurans CH34 cells were suspended in mineral water supplemented with or without crushed basalt and send for 3 months on board the Russian FOTON-M4 capsule. Long-term storage had a significant impact on cell physiology and energy status (by flow cytometry analysis, plate count and intracellular ATP measurements as 60% of cells stored on ground lost their cell membrane potential, only 17% were still active, average ATP levels per cell were significantly lower and cultivability dropped to 1%. The cells stored in the presence of basalt and exposed to space flight conditions during storage however showed less dramatic changes in physiology, with only 16% of the cells lost their cell membrane potential and 24% were still active, leading to a higher cultivability (50% and indicating a general positive effect of basalt and space flight on survival. Microbe-mineral interactions and biofilm formation was altered by spaceflight as less biofilm was formed on the basalt during flight conditions. Leaching from basalt also changed (measured with ICP-OES, showing that cells release more copper from basalt and the presence of cells also impacted iron and magnesium concentration irrespective of the presence of basalt. The flight conditions thus could counteract some of the detrimental effects observed after the 3 month storage conditions.

  15. Eficiência simbiótica de estirpes de Cupriavidus necator tolerantes a zinco, cádmio, cobre e chumbo

    Directory of Open Access Journals (Sweden)

    Paulo Ademar Avelar Ferreira

    2012-01-01

    Full Text Available O objetivo deste trabalho foi avaliar a tolerância de estirpes de Cupriavidus necator a zinco, cádmio, cobre e chumbo, além de determinar a eficiência simbiótica das estirpes mais tolerantes em associação a espécies leguminosas com potencial para revegetação. A tolerância foi testada em meio LB, suplementado com 2,5; 5,0; 7,5; 10; 12,5 e 15 mmol L-1 de ZnSO4.7H2O, CdSO4.8H2O, CuSO4.5H2O e PbCl2, respectivamente, em comparação ao controle sem adição de metal. Determinou-se a eficiência simbiótica das quatro estirpes de C. necator mais tolerantes aos metais avaliados (UFLA02-71, UFLA02-73, UFLA01-659 e UFLA01-663, as quais foram inoculadas nas espécies: Leucaena leucocephala, Enterolobium contortisiliquum, Acacia mangium, Mimosa caesalpiniifolia, M. pudica, M. pigra e M. acutistipula. Em vasos com solos, avaliaram-se L. leucocephala, M. pudica e M. caesalpiniifolia e as estirpes UFLA01-659 e UFLA02-71, selecionadas na avaliação de eficiência simbiótica. A estirpe UFLA02-71 proporcionou incrementos de matéria seca da parte aérea de 870% em M. caesalpiniifolia, enquanto que UFLA01-659 proporcionou 885% em M. pudica e 924% em L. leucocephala. As estirpes UFLA01-659 e UFLA02-71, além da alta tolerância a metais pesados, apresentaram eficiência em fixar nitrogênio, em simbiose com essas leguminosas, em solos com rizóbios nativos capazes de nodulá-las, e devem ser avaliadas quanto ao seu potencial de utilização em programas de recuperação de áreas degradadas.

  16. Study of the Cupriavidus metallidurans CH34 resistance of selenite and selenate oxy-anions: accumulation, localisation and transformation of selenium; Etude de la resistance de Cupriavidus metallidurans CH34 aux oxyanions selenite et seleniate: accumulation, localisation et transformation du selenium

    Energy Technology Data Exchange (ETDEWEB)

    Avoscan, L

    2007-06-15

    Selenium is an essential trace element for the living organisms but it is very toxic at high concentration. Selenite and selenate oxides, soluble forms, highly toxic and bio-assimilable, are the most prevalent forms in the environment. Some soil micro-organisms play a dominant role and contribute to the natural cycle of selenium. Our study model, Cupriavidus (formerly Ralstonia) metallidurans CH34, a telluric bacterium characteristic of metal-contaminated biotopes, is known to resist selenite by reducing it into elemental selenium, an insoluble and less toxic form of selenium. In order to better understand the mechanisms of selenium reduction in the bacteria, three methods of speciation were combined (XAS (XANES and EXAFS), HPLC-ICP-MS and SDS-PAGEPIXE). They were completed by the direct quantification of selenium accumulated in the bacteria. Speciation analyses highlighted the existence of two mechanisms of reduction of selenium oxides in C. metallidurans CH34. Assimilation transforms selenite and selenate into organic selenium, identified as seleno-methionine and leads to its non-specific incorporation into bacterial proteins (presence of selenious proteins). Detoxication precipitates selenite in nano-particles of elemental selenium. This way of detoxication is not set up after an exposure to selenate although it is nevertheless possible to detect elemental selenium but in very small amount compared to the exposure of selenite. Seleno-diglutathion is detected in bacteria stressed by an exposure to selenate in medium limited in sulphate. Bacteria exposed to selenite accumulate 25 times more selenium than when they are exposed to selenate. The study of mutants resistant to selenite, which do not express the membrane protein DedA, showed that the accumulation of selenium after exposure to selenite is decreased compared with the wild strain meaning probable link between the transport of selenite and the DedA protein. Finally, selenate would use the sulphate permease

  17. Valorization of waste glycerol for the production of poly (3-hydroxybutyrate) and poly (3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer by Cupriavidus necator and extraction in a sustainable manner.

    Science.gov (United States)

    Gahlawat, Geeta; Soni, Sanjeev Kumar

    2017-11-01

    Glycerol is a by-product of many industrial processes and huge amounts of it are generated in the form of waste, thereby necessitating a search for the method of its disposal. An interesting solution is the valorization of crude glycerol into value added product such as polyhydroxyalkanoates (PHAs). The feasibility of producing PHAs by Cupriavidus necator was evaluated using crude glycerol (WG). Various cultivation strategies were designed for the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer by adding different organic acids as precursors at different concentrations levels. Batch cultivation of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) production showed accumulation of 6.76g/L biomass containing 4.84g/L copolymer on WG with a maximum 3-hydroxyvalerate content of 24.6mol%. PHAs extraction using a non-toxic and recyclable solvent, 1,2 propylene carbonate, showed the highest recovery yield (90%) and purity (93%) at 120°C temperature and 30min incubation. This is the first report on jatropha based glycerol valorization for poly(3-hydroxybutyrate-co-3-hydroxyvalerate) production coupled with extraction using non-toxic solvent. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Polyaromatic hydrocarbon (PAH) degradation potential of a new acid tolerant, diazotrophic P-solubilizing and heavy metal resistant bacterium Cupriavidus sp. MTS-7 isolated from long-term mixed contaminated soil.

    Science.gov (United States)

    Kuppusamy, Saranya; Thavamani, Palanisami; Megharaj, Mallavarapu; Lee, Yong Bok; Naidu, Ravi

    2016-11-01

    An isolate of Cupriavidus (strain MTS-7) was identified from a long-term PAHs and heavy metals mixed contaminated soil with the potential to biodegrade both LMW and HMW PAHs with added unique traits of acid and alkali tolerance, heavy metal tolerance, self-nutrient assimilation by N fixation and P solubilization. This strain completely degraded the model 3 (150 mg L(-1) Phe), 4 (150 mg L(-1) Pyr) and 5 (50 mg L(-1) BaP) ring PAHs in 4, 20 and 30 days, respectively. It could mineralize 90-100% of PAHs (200 mg L(-1) of Phe and Pyr) within 15 days across pH ranging from 5 to 8 and even in the presence of toxic metal contaminations. During biodegradation, the minimum inhibitory concentrations were 5 (Cu(2+)) and 3 (Cd(2+), Pb(2+), Zn(2+)) mg L(-1) of the potentially bioavailable metal ions and over 17 mg L(-1) metal levels was lethal for the microbe. Further, it could fix 217-274 μg mL(-1) of N and solubilize 79-135 μg mL(-1) of P while PAHs degradation. MTS-7 as a superior candidate could be thus used in the enhanced bioaugmentation and/or phytoremediation of long-term mixed contaminated sites. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Improved fed-batch production of high-purity PHB (poly-3 hydroxy butyrate) by Cupriavidus necator (MTCC 1472) from sucrose-based cheap substrates under response surface-optimized conditions.

    Science.gov (United States)

    Dey, Pinaki; Rangarajan, Vivek

    2017-10-01

    Experimental investigations were carried out for Cupriavidus necator (MTCC 1472)-based improved production of poly-3 hydroxy butyrate (PHB) through induced nitrogen limiting fed-batch cultivation strategies. Initially Plackett-Burman design and response surface methodology were implemented to optimize most influencing process parameters. With optimized process parameter values, continuous feeding strategies ware applied in a 5-l fermenter with table sugar concentration of 100 g/l, nitrogen concentration of 0.12 g/l for fed-batch fermentation with varying dilution rates of 0.02 and 0.046 1/h. To get enriched production of PHB, concentration of the sugar was further increased to 150 and 200 g/l in feeding. Maximum concentrations of PHB achieved were 22.35 and 23.07 g/l at those dilution rates when sugar concentration maintains at 200 g/l in feeding. At maximum concentration of PHB (23.07 g/l), productivity of 0.58 g/l h was achieved with maximum PHB accumulation efficiency up to 64% of the dry weight of biomass. High purity of PHB, close to medical grade was achieved after surfactant hypochlorite extraction method, and it was further confirmed by SEM, EDX, and XRD studies.

  20. Transcriptomic profiling of Burkholderia phymatum STM815, Cupriavidus taiwanensis LMG19424 and Rhizobium mesoamericanum STM3625 in response to Mimosa pudica root exudates illuminates the molecular basis of their nodulation competitiveness and symbiotic evolutionary history.

    Science.gov (United States)

    Klonowska, Agnieszka; Melkonian, Rémy; Miché, Lucie; Tisseyre, Pierre; Moulin, Lionel

    2018-01-30

    Rhizobial symbionts belong to the classes Alphaproteobacteria and Betaproteobacteria (called "alpha" and "beta"-rhizobia). Most knowledge on the genetic basis of symbiosis is based on model strains belonging to alpha-rhizobia. Mimosa pudica is a legume that offers an excellent opportunity to study the adaptation toward symbiotic nitrogen fixation in beta-rhizobia compared to alpha-rhizobia. In a previous study (Melkonian et al., Environ Microbiol 16:2099-111, 2014) we described the symbiotic competitiveness of M. pudica symbionts belonging to Burkholderia, Cupriavidus and Rhizobium species. In this article we present a comparative analysis of the transcriptomes (by RNAseq) of B. phymatum STM815 (BP), C. taiwanensis LMG19424 (CT) and R. mesoamericanum STM3625 (RM) in conditions mimicking the early steps of symbiosis (i.e. perception of root exudates). BP exhibited the strongest transcriptome shift both quantitatively and qualitatively, which mirrors its high competitiveness in the early steps of symbiosis and its ancient evolutionary history as a symbiont, while CT had a minimal response which correlates with its status as a younger symbiont (probably via acquisition of symbiotic genes from a Burkholderia ancestor) and RM had a typical response of Alphaproteobacterial rhizospheric bacteria. Interestingly, the upregulation of nodulation genes was the only common response among the three strains; the exception was an up-regulated gene encoding a putative fatty acid hydroxylase, which appears to be a novel symbiotic gene specific to Mimosa symbionts. The transcriptional response to root exudates was correlated to each strain nodulation competitiveness, with Burkholderia phymatum appearing as the best specialised symbiont of Mimosa pudica.

  1. Characterization of Phosphate Solubilizing Bacteria in Sediments from a Shallow Eutrophic Lake and a Wetland: Isolation, Molecular Identification and Phosphorus Release Ability Determination

    Directory of Open Access Journals (Sweden)

    Jie Tang

    2010-11-01

    Full Text Available The transformation of phosphorus (P is a major factor of lake eutrophication, and phosphate releasing bacteria play an important role in the release process. Experiments were conducted to investigate P content and characterize phosphate solubilizing bacterial composition at the molecular level in a shallow eutrophic lake and a wetland. Results showed that P concentrations were relatively high and derived from agricultural runoff and domestic or industrial pollution. Enumeration and molecular identification of these strains indicated that these bacterial groups were abundant in the ecosystem and various kinds of bacteria participated in the phosphorus release process. Twelve phosphate solubilizing bacteria, including eight organic P-solubilizing bacteria (OPBs and four inorganic P-solubilizing bacteria (IPBs, which belonged to three different families, were isolated and identified. Cupriavidus basilensis was found for the first time to have the ability to mineralize organic P (OP. Laboratory tests on P release ability revealed that IPBs were more effective at releasing P than OPBs. The most efficient IPB strain could accumulate over 170 mg·L-1 orthophosphate, while the equivalent OPB strain only liberated less than 4 mg·L-1 orthophosphate in liquid culture. The results obtained from this investigation should help clarify the roles of microorganisms in aquatic systems and the mechanisms of eutrophication.

  2. POLY(3-HYDROXYBUTYRATE) PRODUCTION BY Cupriavidus necator SUPPLEMENTED WITH MINIEMULSIFIED SOYBEAN OIL

    OpenAIRE

    Schmidt, M.; Ienczak, J. L.; Quines, L. K.; Zanfonato, K.; Schmidell, W.; Aragão, G. M. F.

    2016-01-01

    Abstract Studies have shown that the supplementation of vegetable oils, in poly(3-hydroxybutyrate) production, provides an increase in the process productivity, besides inducing lipase activity in the medium. The supplementation with miniemulsified oils could potentialize these results. In this work, the influence of supplementation of the medium with soybean oil, without treatment and miniemulsified, on polymerr production was evaluated. The best moment to supplement the medium and its influ...

  3. Disinfection of Spacecraft Potable Water Systems by Photocatalytic Oxidation Using UV-A Light Emitting Diodes

    Science.gov (United States)

    Birmele, Michele N.; O'Neal, Jeremy A.; Roberts, Michael S.

    2011-01-01

    Ultraviolet (UV) light has long been used in terrestrial water treatment systems for photodisinfection and the removal of organic compounds by several processes including photoadsorption, photolysis, and photocatalytic oxidation/reduction. Despite its effectiveness for water treatment, UV has not been explored for spacecraft applications because of concerns about the safety and reliability of mercury-containing UV lamps. However, recent advances in ultraviolet light emitting diodes (UV LEDs) have enabled the utilization of nanomaterials that possess the appropriate optical properties for the manufacture of LEDs capable of producing monochromatic light at germicidal wavelengths. This report describes the testing of a commercial-off-the-shelf, high power Nichia UV-A LED (250mW A365nnJ for the excitation of titanium dioxide as a point-of-use (POD) disinfection device in a potable water system. The combination of an immobilized, high surface area photocatalyst with a UV-A LED is promising for potable water system disinfection since toxic chemicals and resupply requirements are reduced. No additional consumables like chemical biocides, absorption columns, or filters are required to disinfect and/or remove potentially toxic disinfectants from the potable water prior to use. Experiments were conducted in a static test stand consisting of a polypropylene microtiter plate containing 3mm glass balls coated with titanium dioxide. Wells filled with water were exposed to ultraviolet light from an actively-cooled UV-A LED positioned above each well and inoculated with six individual challenge microorganisms recovered from the International Space Station (ISS): Burkholderia cepacia, Cupriavidus metallidurans, Methylobacterium fujisawaense, Pseudomonas aeruginosa, Sphingomonas paucimobilis and Wautersia basilensis. Exposure to the Nichia UV-A LED with photocatalytic oxidation resulted in a complete (>7-log) reduction of each challenge bacteria population in UV-A LEDs and semi

  4. A bionic system with Fenton reaction and bacteria as a model for bioprocessing lignocellulosic biomass.

    Science.gov (United States)

    Zhang, Kejing; Si, Mengying; Liu, Dan; Zhuo, Shengnan; Liu, Mingren; Liu, Hui; Yan, Xu; Shi, Yan

    2018-01-01

    The recalcitrance of lignocellulosic biomass offers a series of challenges for biochemical processing into biofuels and bio-products. For the first time, we address these challenges with a biomimetic system via a mild yet rapid Fenton reaction and lignocellulose-degrading bacterial strain Cupriavidus basilensis B-8 (here after B-8) to pretreat the rice straw (RS) by mimicking the natural fungal invasion process. Here, we also elaborated the mechanism through conducting a systematic study of physicochemical changes before and after pretreatment. After synergistic Fenton and B-8 pretreatment, the reducing sugar yield was increased by 15.6-56.6% over Fenton pretreatment alone and 2.7-5.2 times over untreated RS (98 mg g -1 ). Morphological analysis revealed that pretreatment changed the surface morphology of the RS, and the increase in roughness and hydrophilic sites enhanced lignocellulose bioavailability. Chemical components analyses showed that B-8 removed part of the lignin and hemicellulose which caused the cellulose content to increase. In addition, the important chemical modifications also occurred in lignin, 2D NMR analysis of the lignin in residues indicated that the Fenton pretreatment caused partial depolymerization of lignin mainly by cleaving the β- O -4 linkages and by demethoxylation to remove the syringyl (S) and guaiacyl (G) units. B-8 could depolymerize amount of the G units by cleaving the β-5 linkages that interconnect the lignin subunits. A biomimetic system with a biochemical Fenton reaction and lignocellulose-degrading bacteria was confirmed to be able for the pretreatment of RS to enhance enzymatic hydrolysis under mild conditions. The high digestibility was attributed to the destruction of the lignin structure, partial hydrolysis of the hemicellulose and partial surface oxidation of the cellulose. The mechanism of synergistic Fenton and B-8 pretreatment was also explored to understand the change in the RS and the bacterial effects on

  5. Solution NMR Structure of Hypothetical Protein CV_2116 Encoded by a Viral Prophage Element in Chromobacterium violaceum

    Directory of Open Access Journals (Sweden)

    Yunhuang Yang

    2012-06-01

    Full Text Available CV_2116 is a small hypothetical protein of 82 amino acids from the Gram-negative coccobacillus Chromobacterium violaceum. A PSI-BLAST search using the CV_2116 sequence as a query identified only one hit (E = 2e−07 corresponding to a hypothetical protein OR16_04617 from Cupriavidus basilensis OR16, which failed to provide insight into the function of CV_2116. The CV_2116 gene was cloned into the p15TvLic expression plasmid, transformed into E. coli, and 13C- and 15N-labeled NMR samples of CV_2116 were overexpressed in E. coli and purified for structure determination using NMR spectroscopy. The resulting high-quality solution NMR structure of CV_2116 revealed a novel α + β fold containing two anti-parallel β -sheets in the N-terminal two-thirds of the protein and one α-helix in the C-terminal third of the protein. CV_2116 does not belong to any known protein sequence family and a Dali search indicated that no similar structures exist in the protein data bank. Although no function of CV_2116 could be derived from either sequence or structural similarity searches, the neighboring genes of CV_2116 encode various proteins annotated as similar to bacteriophage tail assembly proteins. Interestingly, C. violaceum exhibits an extensive network of bacteriophage tail-like structures that likely result from lateral gene transfer by incorporation of viral DNA into its genome (prophages due to bacteriophage infection. Indeed, C. violaceum has been shown to contain four prophage elements and CV_2116 resides in the fourth of these elements. Analysis of the putative operon in which CV_2116 resides indicates that CV_2116 might be a component of the bacteriophage tail-like assembly that occurs in C. violaceum.

  6. NCBI nr-aa BLAST: CBRC-MLUC-01-0418 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available ol deshydrogenase (AdhA) [Cupriavidus taiwanensis] emb|CAQ69467.1| putative three-component membrane-bound a...lcohol deshydrogenase (AdhA) [Cupriavidus taiwanensis] YP_002005534.1 0.34 27% ...

  7. Identification of two combined genes responsible for dechlorination of 3,5,6-trichloro-2-pyridinol (TCP) in Cupriavidus pauculus P2.

    Science.gov (United States)

    Cao, Li; Xu, Jianhong; Wu, Guang; Li, Mingxing; Jiang, Jiandong; He, Jian; Li, Shunpeng; Hong, Qing

    2013-09-15

    Dehalogenation is an important mechanism for degrading and detoxifying halogenated aromatics in microbes. However, the biochemical and molecular mechanisms of dehalogenation of 3,5,6-trichloro-2-pyridinol (TCP) are still unknown. In this study, a novel 6012 bp gene cluster was cloned from TCP-degrading strain P2, which was responsible for the dehalogenation of TCP. The cluster included a monooxygenase gene (tcpA1), a flavin reductase gene (tcpB1), tcpR1, orf1 and orf2. TcpA1 and TcpB1 were indispensable for the dehalogenation of TCP. They worked together to catalyze the dehalogenation of three chlorine of TCP, and generated a more readily biodegradable product of 3,6-dihydroxypyridine-2,5-dione. TcpA1 displayed the highest activity against TCP at 40°C and at pH 8.0. Cu(2+), Zn(2+), and Hg(2+) significantly inhibited enzyme activity. To the best of our knowledge, this is the first report on a gene cluster responsible for TCP degradation. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Cupriavidus pinatubonensis AEO106 deals with copper-induced oxidative stress before engaging in biodegradation of the herbicide 4-chloro-2-methylphenoxyacetic acid

    DEFF Research Database (Denmark)

    Svenningsen, Nanna Bygvraa; Damgaard, Mette; Rasmussen, Maria Katrine

    2017-01-01

    to Cu leads to accumulation of intracellular reactive oxygen species (ROS) in some bacteria, but it is not known how Cu-derived ROS and an ensuing oxidative stress affect the degradation of PA herbicides. Based on the previously proposed paradigm that bacteria deal with environmental stress before...... that it is involved in the oxidative stress response in C. pinatubonensis. The increased ROS accumulation and increased expression of the oxidative stress defense coincided with a delay in the catabolic performance, since both expression of the catabolic tfdA gene and MCPA mineralization were delayed compared...... increased accumulation of ROS measured by the oxidant sensing probe 2,7-dichlorodihydrofluorescein diacetate and flow cytometry, and resulted in upregulation of a gene encoding a protein belong to the Ohr/OsmC protein family. The ohr/osmC gene was also highly induced by H2O2 exposure suggesting...

  9. Footprint area analysis of binary imaged Cupriavidus necator cells to study PHB production at balanced, transient, and limited growth conditions in a cascade process.

    Science.gov (United States)

    Vadlja, Denis; Koller, Martin; Novak, Mario; Braunegg, Gerhart; Horvat, Predrag

    2016-12-01

    Statistical distribution of cell and poly[3-(R)-hydroxybutyrate] (PHB) granule size and number of granules per cell are investigated for PHB production in a five-stage cascade (5CSTR). Electron microscopic pictures of cells from individual cascade stages (R1-R5) were converted to binary pictures to visualize footprint areas for polyhydroxyalkanoate (PHA) and non-PHA biomass. Results for each stage were correlated to the corresponding experimentally determined kinetics (specific growth rate μ and specific productivity π). Log-normal distribution describes PHA granule size dissimilarity, whereas for R1 and R4, gamma distribution best reflects the situation. R1, devoted to balanced biomass synthesis, predominately contains cells with rather small granules, whereas with increasing residence time τ, maximum and average granule sizes by trend increase, approaching an upper limit determined by the cell's geometry. Generally, an increase of intracellular PHA content and ratio of granule to cell area slow down along the cascade. Further, the number of granules per cell decreases with increasing τ. Data for μ and π obtained by binary picture analysis correlate well with the experimental results. The work describes long-term continuous PHA production under balanced, transient, and nutrient-deficient conditions, as well as their reflection on the granules size, granule number, and cell structure on the microscopic level.

  10. Produção de poli(3-hidroxibutirato por Cupriavidus Necator em meio hidrolisado de amido de arroz com suplementação de óleo de soja em diferentes temperaturas Production of poly(3-hydroxybutyrate by Cupriavidus Necator in hydrolyzed rice starch medium with soybean oil supplementation at different temperatures

    Directory of Open Access Journals (Sweden)

    Francieli Dalcanton

    2010-01-01

    Full Text Available Poly (3-hydroxybutyrate (P(3HB is a biopolymer, completely biodegradable, which has similar properties to fuel-based polymers. However to make it economically competitive it is necessary the study of cheap sources of substrate. The influence of hydrolyzed rice starch supplemented with soybean oil at different temperatures (30, 35 and 40 °C was studied in the production of P(3HB by C. necator. The percentage of P(3HB produced in the cultures at 30, 35 °C was 30, 39% and 35, 43% without and with supplementation of oil, respectively. The culture at 40 °C showed no production phase due to a possible oxygen limitation. These results demonstrate that hydrolyzed rice starch supplemented with soybean oil increases the yield of P(3HB and temperature of 35 ºC is the most favorable for biopolymer production.

  11. Dicty_cDB: Contig-U04424-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available _2( CU633751 |pid:none) Cupriavidus taiwanensis str. LMG19... 36 0.93 BT065311_1(...a sp. wRi, complete geno... 33 7.9 >CU633751_2( CU633751 |pid:none) Cupriavidus taiwanensis str. LMG19424 pl

  12. AcEST: BP917133 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 775_CUPTR Putative PROPIONYL-COA CARBOXYLASE (BETA SUBUNIT) PROTEIN OS=Cupriavidus taiwan...TA SUBUNIT) PROTEIN OS=Cupriavidus taiwanensis (strain R1 / LMG 19424) GN=RALTA_A2850 PE=4 SV=1 Length = 533

  13. Dicty_cDB: SLE686 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 016 |pid:none) Xenopus tropicalis methylcrotonoyl... 324 2e-87 CU633749_120( CU633749 |pid:none) Cupriavidus taiwan... 2e-87 CU633749_1505( CU633749 |pid:none) Cupriavidus taiwanensis str. LM... 323

  14. AcEST: BP915397 [AcEST

    Lifescience Database Archive (English)

    Full Text Available UPTR Putative uncharacterized protein OS=Cupriavidus taiwanensis (strain R1 / LMG...Cupri... 33 9.9 >tr|B3R9M4|B3R9M4_CUPTR Putative uncharacterized protein OS=Cupriavidus taiwanensis (strain

  15. Dicty_cDB: AFM534 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available chloromonas aromatica RCB, comp... 315 2e-84 CU633749_120( CU633749 |pid:none) Cupriavidus taiwan...et... 313 9e-84 CU633749_1505( CU633749 |pid:none) Cupriavidus taiwanensis str. LM... 313 9e-84 (Q5XIT9) Rec

  16. Dicty_cDB: VFA387 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available e) Dechloromonas aromatica RCB, comp... 315 3e-84 CU633749_120( CU633749 |pid:none) Cupriavidus taiwanensis ...complet... 313 1e-83 CU633749_1505( CU633749 |pid:none) Cupriavidus taiwanensis str. LM... 313 1e-83 protein

  17. AcEST: BP914624 [AcEST

    Lifescience Database Archive (English)

    Full Text Available t_id B2AIZ9 Definition tr|B2AIZ9|B2AIZ9_CUPTR Fused transposase IS66/IS21 OS=Cupriavidus taiwanensis (strain...Z9|B2AIZ9_CUPTR Fused transposase IS66/IS21 OS=Cupriavidus taiwanensis (strain R1

  18. NCBI nr-aa BLAST: CBRC-MMUR-01-1593 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MMUR-01-1593 ref|YP_002007133.1| methionyl-tRNA formyltransferase [Cupriavidus taiwan...ensis] emb|CAQ71072.1| 10-formyltetrahydrofolate:L-methionyl-tRNA(fMet) N-formyltransferase [Cupriavidus taiwanensis] YP_002007133.1 7.7 32% ...

  19. Poly(3-hydroxybutyrate) production in an integrated electromicrobial setup: Investigation under stress-inducing conditions

    KAUST Repository

    Al Rowaihi, Israa Salem; Paillier, Alexis; Rasul, Shahid; Karan, Ram; Grö tzinger, Stefan Wolfgang; Takanabe, Kazuhiro; Eppinger, Jö rg

    2018-01-01

    extorquens AM1 and Cupriavidus necator H16. This setup allows to investigate the influence of different stress conditions, such as coexisting electrolysis, relatively high salinity, nutrient limitation, and starvation, on the production of PHB. The overall

  20. Influence of bacteria on degradation of bioplastics

    Science.gov (United States)

    Blinková, M.; Boturová, K.

    2017-10-01

    The degradation rate of bioplastic in soil is closely related to the diversity of soil microbiota. To investigate the effect of soil bacterial on biodegradation, 4 bacterial strains of soil - Pseudomonas chlororaphis, Kocuria rosea, Cupriavidus necator and Bacillus cereus, were used to accelerate the decomposition of bioplastics manufactured from Polylactid acid (PLA) by direct action during 250 days. The best results were obtained with bacterial strains Cupriavidus necator and Pseudomonas chlororaphis that were isolated of lagoons with anthropogenic sediments.

  1. AcEST: DK953842 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 37 0.74 tr|B3R4M5|B3R4M5_CUPTR Histone deacetylase OS=Cupriavidus taiwan... 36 0.96 tr|B1XVX0|B1XVX0_POLNS ...3R4M5|B3R4M5_CUPTR Histone deacetylase OS=Cupriavidus taiwanensis (strain R1 / LMG 19424) GN=RALTA_A1299 PE=

  2. Gene clusters involved in isethionate degradation by terrestrial and marine bacteria.

    KAUST Repository

    Weinitschke, Sonja; Sharma, Pia I; Stingl, Ulrich; Cook, Alasdair M; Smits, Theo H M

    2010-01-01

    Ubiquitous isethionate (2-hydroxyethanesulfonate) is dissimilated by diverse bacteria. Growth of Cupriavidus necator H16 with isethionate was observed, as was inducible membrane-bound isethionate dehydrogenase (IseJ) and inducible transcription of the genes predicted to encode IseJ and a transporter (IseU). Biodiversity in isethionate transport genes was observed and investigated by transcription experiments.

  3. Dicty_cDB: SSI516 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available |pid:none) Cupriavidus taiwanensis str. LM... 141 2e-32 AM260479_1059( AM260479 ...e-33 CP000384_1738( CP000384 |pid:none) Mycobacterium sp. MCS, complete... 142 5e-33 CU633749_1028( CU633749

  4. Dicty_cDB: [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available |pid:none) Cupriavidus taiwanensis str. LM... 34 4.1 AE015928_2526( AE015928 |pid:none) Bacteroides thetaiot...168 |pid:none) Ralstonia solanacearum strain I... 35 3.1 CU633749_1834( CU633749

  5. Biotechnological strategies to improve production of microbial poly-(3-hydroxybutyrate): a review of recent research work

    OpenAIRE

    Peña, C; Castillo, T; García, A; Millán, M; Segura, D

    2014-01-01

    Poly-(3-hydroxybutyrate) [P(3HB)] is a polyester synthesized as a carbon and energy reserve material by a wide number of bacteria. This polymer is characterized by its thermo-plastic properties similar to plastics derived from petrochemical industry, such as polyethylene and polypropylene. Furthermore, P(3HB) is an inert, biocompatible and biodegradable material which has been proposed for several uses in medical and biomedical areas. Currently, only few bacterial species such as Cupriavidus ...

  6. The presence of PHB granules in cytoplasm protects non-halophilic bacterial cells against the harmful impact of hypertonic environments

    Czech Academy of Sciences Publication Activity Database

    Obruča, S.; Sedláček, P.; Mravec, F.; Krzyžánek, Vladislav; Nebesářová, Jana; Samek, Ota; Kučera, D.; Benešová, P.; Hrubanová, Kamila; Milerová, M.; Márová, I.

    2017-01-01

    Roč. 39, OCT (2017), s. 68-80 ISSN 1871-6784 R&D Projects: GA ČR(CZ) GA15-20645S Institutional support: RVO:68081731 ; RVO:60077344 Keywords : Poly(3-hydroxybutyrate) * PHB * cupriavidus necator * hyperosmotic conditions * plasmolysis * stress conditions Subject RIV: BH - Optics, Masers, Lasers; CE - Biochemistry (BC-A) OBOR OECD: Electrical and electronic engineering; Electrical and electronic engineering (BC-A) Impact factor: 3.813, year: 2016

  7. C:\\Users\\HP Pro 2000\\Desktop\\KOUADJO G..xps

    African Journals Online (AJOL)

    HP Pro 2000

    Soixante-six Staphylococci résistants au chrome appartenant aux espèces : S. epidermidis, S. aureus, S. saprophyticus et S. arlettae ont été ... chr du plasmide pMOL28 qui confère la résistance au chrome chez Cupriavidus metallidurans. Par utilisation .... cycles of 94 °C for 30 seconds, 59 ºC for. 30 seconds and 72 ºC for ...

  8. Planetary protection protecting earth and planets against alien microbes

    International Nuclear Information System (INIS)

    Leys, N.

    2006-01-01

    Protecting Earth and planets against the invasion of 'alien life forms' is not military science fiction, but it is the peaceful daily job of engineers and scientists of space agencies. 'Planetary Protection' is preventing microbial contamination of both the target planet and the Earth when sending robots on interplanetary space mission. It is important to preserve the 'natural' conditions of other planets and to not bring with robots 'earthly microbes' (forward contamination) when looking for 'spores of extra terrestrial life'. The Earth and its biosphere must be protected from potential extraterrestrial biological contamination when returning samples of other planets to the Earth (backward contamination). The NASA-Caltech Laboratory for Planetary Protection of Dr. Kasthuri Venkateswaran at the Jet Propulsion Laboratory (JPL) (California, USA) routinely monitors and characterizes the microbes of NASA spacecraft assembly rooms and space robots prior to flight. They have repeatedly isolated Cupriavidus and Ralstonia strains pre-flight from spacecraft assembly rooms (floor and air) and surfaces of space robots such as the Mars Odyssey Orbiter (La Duc et al., 2003). Cupriavidus and Ralstonia strains have also been found in-flight, in ISS cooling water and Shuttle drinking water (Venkateswaran et al., Pyle et al., Ott et al., all unpublished). The main objective of this study is to characterise the Cupriavidus and Ralstonia strains isolated at JPL and compare them to the Cupriavidus metallidurans CH34T model strain, isolated from a Belgian contaminated soil and studied since 25 years at SCK-CEN and to enhance our knowledge by performing additional tests at JPL and gathering information regarding the environmental conditions and the cleaning and isolation methods used in such spacecraft assembling facilities

  9. Assessment of the Residual Life of Steam Pipeline Material beyond the Computational Working Time

    Directory of Open Access Journals (Sweden)

    Marek Sroka

    2017-03-01

    Full Text Available This paper presents the evaluation of durability for the material of repair welded joints made from (13HMF 14MoV6-3 steel after long-term service, and from material in the as-received condition and after long-term service. Microstructure examinations using a scanning electron microscope, hardness measurements and creep tests of the basic material and welded joints of these steels were carried out. These tests enabled the time of further safe service of the examined repair welded joints to be determined in relation to the residual life of the materials. The evaluation of residual life and disposable life, and thus the estimation and determination of the time of safe service, is of great importance for the operation of components beyond the design service life. The obtained test results are part of the materials’ characteristics developed by the Institute for Ferrous Metallurgy for steels and welded joints made from these steels to work under creep conditions.

  10. Isolation, identification, and environmental adaptability of heavy-metal-resistant bacteria from ramie rhizosphere soil around mine refinery

    OpenAIRE

    Jiang, Jie; Pan, Chaohu; Xiao, Aiping; Yang, Xiai; Zhang, Guimin

    2017-01-01

    Six bacteria strains from heavy-metal-polluted ramie rhizosphere soil were isolated through Cd2+ stress, which were numbered as JJ1, JJ2, JJ10, JJ11, JJ15, and JJ18. Sequence alignment and phylogenic analysis showed that strain JJ1 belonged to Pseudomonas, strain JJ2 belonged to Cupriavidus, strains JJ11 and JJ15 belonged to Bacillus, and strains JJ10 and JJ18 belonged to Acinetobacter. The tolerance capability of all the strains was the trend of Pb2+?>?Zn2+?>?Cu2+?>?Cd2+, the maximum toleran...

  11. Surviving space flight: case study on MELiSSA's CIII nitrifying compartment

    Science.gov (United States)

    Ilgrande, Chiara; Lasseur, Christophe; Mastroleo, Felice; Paille, Christel; Leys, Natalie; Morozova, Julia; Ilyin, Vyacheslav; Clauwaert, Peter; Christiaens, Marlies E. R.; Lindeboom, Ralph E. F.; Vlaeminck, Siegfried; Prat, Delphine; Arroyo, Jose M. C.; Conincx, Ilse; Van Hoey, Olivier; Roume, Hugo; Udert, Kai; Sas, Benedikt

    2016-07-01

    Space synthetic biology offers key opportunities for long-term space missions. Planets mining, terraformation, space medicine and Life Support technologies would all benefit from an integrative biological approach. However, space is a harsh environment for life: microgravity, temperature, UV and cosmic radiation can affect the health and functionality of microorganisms and plants, possibly preventing the optimal performance of the systems. The European Space Agency's Life Support System (MELiSSA) has been developed as a model for future long term Space missions and Space habitation. MELiSSA is a 5 compartment artificial ecosystem with microorganisms and higher, that aims at completely recycling gas, liquid and solid waste. In this study, the survival and functional activity after Lower Earth Orbit conditions of microbial nitrogen conversions, relevant for MELiSSA's CIII compartment, was tested. Synthetic communities containing Nitrosomonas europeae, Nitrosomonas ureae, Nitrobacter winogradskyi, Nitrospira moscoviensis and Cupriavidus pinatubonensis were exposed to the Lower Earth Orbit conditions of the International Space Station (ISS) for 7 days. Nitrosomonas europeae, Nitrobacter winogradskyi, Cupriavidus pinatubonensis, and three mixed communities (a urine nitrification sludge, a sludge containing aerobic ammonia oxidizing bacteria and anammox bacteria (OLAND), and an aquaculture sludge containing ammonia oxidizing archaea) were exposed to Lower Earth Orbit conditions for 44 days. Survival after both space flights was demonstrated because nitritation, nitratation, denitrification and anammox activity could be restored at a rate comparable to ground storage conditions. Our results validate the potential survival feasibility and suggest future space applications for N-related microorganisms.

  12. Bacterial genomic adaptation and response to metals

    International Nuclear Information System (INIS)

    Van Houdt, R.

    2009-01-01

    The beta-proteobacterium Cupriavidus metallidurans CH34 (formerly Ralstonia metallidurans) has been intensively studied since 1976 in SCK-CEN and VITO, for its adaptation capacity to survive in harsh (mostly industrial) environments, to overcome acute environmental stresses, for its resistance to a variety of heavy metals and for applications in environmental biotechnology. Recently, CH34 has become a model bacterium to study the effect of spaceflight conditions in several space flight experiments conducted by SCK-CEN (e.g. MESSAGE, BASE). Furthermore, Cupriavidus and Ralstonia species are isolated from the floor, air and surfaces of spacecraft assembly rooms; were found prior-to-flight on surfaces of space robots such as the Mars Odyssey Orbiter and even in-flight in ISS cooling water and Shuttle drinking water, vindicating its role as model bacterium in space research. In addition, Ralstonia species are also the causative agent of nosocomial infections and are among the unusual species recovered from cystic fibrosis (CF) patients. The genomic organization of Cuprivavidus metallidurans CH34 was studied in-depth to identify the genetic and regulatory structures involved in the resistance to heavy metals

  13. Biotechnological strategies to improve production of microbial poly-(3-hydroxybutyrate): a review of recent research work.

    Science.gov (United States)

    Peña, C; Castillo, T; García, A; Millán, M; Segura, D

    2014-07-01

    Poly-(3-hydroxybutyrate) [P(3HB)] is a polyester synthesized as a carbon and energy reserve material by a wide number of bacteria. This polymer is characterized by its thermo-plastic properties similar to plastics derived from petrochemical industry, such as polyethylene and polypropylene. Furthermore, P(3HB) is an inert, biocompatible and biodegradable material which has been proposed for several uses in medical and biomedical areas. Currently, only few bacterial species such as Cupriavidus necator, Azohydromonas lata and recombinant Escherichia coli have been successfully used for P(3HB) production at industrial level. Nevertheless, in recent years, several fermentation strategies using other microbial models such as Azotobacter vinelandii, A. chroococcum, as well as some methane-utilizing species, have been developed in order to improve the P(3HB) production and also its mean molecular weight. © 2014 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  14. Adhesion to sand and ability to mineralise low pesticide concentrations are required for efficient bioaugmentation of flow-through sand filters

    DEFF Research Database (Denmark)

    Samuelsen, Elin Djurhuus; Badawi, Nora; Nybroe, Ole

    2017-01-01

    (Sphingomonas sp. PM2, Sphingomonas sp. ERG5, Burkholderia sp. TFD34, Cupriavidus sp. TFD38) were characterised with regard to their motility, cell surface hydrophobicity, biofilm formation, adhesion behaviour and ability to mineralise MCPA. Strains PM2 and ERG5 were non-motile and hydrophobic, whilst strains...... TFD34 and TFD38 were motile and less hydrophobic. All the strains except ERG5 showed low biofilm formation on polystyrene, although it was significantly higher on glass. PM2 was the most efficient MCPA degrader as it displayed no lag phase and reached >50 % mineralisation at all concentrations (0.......0016-25 mg L(-1)). PM2 adhered significantly better to sand than the other strains. No link was found between motility, biofilm formation and the ability to adhere to sand. PM2 completely removed MCPA for 14 days when inoculated in sand columns with a constant inlet of 1 mg L(-1) MCPA. These results...

  15. Assessment of uranium and selenium speciation in human and bacterial biological models to probe changes in their structural environment

    Energy Technology Data Exchange (ETDEWEB)

    Avoscan, L.; Milgram, S.; Untereiner, G.; Collins, R.; Khodja, H.; Carriere, M.; Gouget, B. [Lab. Pierre Sue, CEA-CNRS UMR 9956, CEA/Saclay, Gif-sur-Yvette (France); Coves, J. [Inst. de Biologie Structurale - J.-P. Ebel, Lab. des Proteines Membranaires, Grenoble (France); Hazemann, J.L. [Lab. de Geophysique Interne et Tectonopbysique, UMR CNRS/Univ. Joseph Fourier, Saint-Martin-D' Heres (France)

    2009-07-01

    This study illustrates the potential of physicochemical techniques to speciate uranium (U) and selenium (Se) in biological samples. Speciation, defined he0re as the study of structural environment, of both toxic elements, was characterized at several levels in biological media and directly in human cells or bacteria once the metal(loid)s were internalized. External speciation that is extracellular speciation in culture media was predicted by thermodynamic equilibrium computer modelling using the JChess software and validated by spectroscopic measurements (XANES and EXAFS). Internal speciation that is intracellular speciation in eukaryotic and prokaryotic cells was studied in vitro with a soil bacterium Cupriavidus metallidurans CH34 and ROS 17/2.8 osteoblasts, human cells responsible for bone formation. XANES, EXAFS, HPLC-ICP-MS and SDS-PAGE coupled to particle induced X-ray emission (PIXE) permitted the identification and quantification of complexes formed with organic or inorganic molecules and/or larger proteins. (orig.)

  16. Assessment of uranium and selenium speciation in human and bacterial biological models to probe changes in their structural environment

    International Nuclear Information System (INIS)

    Avoscan, L.; Milgram, S.; Untereiner, G.; Collins, R.; Khodja, H.; Carriere, M.; Gouget, B.; Coves, J.; Hazemann, J.L.

    2009-01-01

    This study illustrates the potential of physicochemical techniques to speciate uranium (U) and selenium (Se) in biological samples. Speciation, defined he0re as the study of structural environment, of both toxic elements, was characterized at several levels in biological media and directly in human cells or bacteria once the metal(loid)s were internalized. External speciation that is extracellular speciation in culture media was predicted by thermodynamic equilibrium computer modelling using the JChess software and validated by spectroscopic measurements (XANES and EXAFS). Internal speciation that is intracellular speciation in eukaryotic and prokaryotic cells was studied in vitro with a soil bacterium Cupriavidus metallidurans CH34 and ROS 17/2.8 osteoblasts, human cells responsible for bone formation. XANES, EXAFS, HPLC-ICP-MS and SDS-PAGE coupled to particle induced X-ray emission (PIXE) permitted the identification and quantification of complexes formed with organic or inorganic molecules and/or larger proteins. (orig.)

  17. Influence of Environmental Stressors on the Physiology of Pollutant Degrading Bacteria

    DEFF Research Database (Denmark)

    Svenningsen, Nanna Bygvraa

    of model degrader bacteria to nutrient- and oxidative stress, two highly relevant stress scenarios in natural environments, and at evaluating the impact of these environmental stress conditions on catabolic gene expression. The results suggest that environmental bacteria, here represented by the toluene...... biodegradative or catabolic performance. To date, details concerning the physiology of degrader microorganisms and their ability to express the relevant catabolic genes in the context of a complex and stressful environment have yet to be elucidated. In order to fully exploit the catabolic potential of degrader......- and xylene degrading bacterium Pseudomonas putida mt-2 and the phenoxy acid herbicide degrading bacterium Cupriavidus pinatubonensis JMP134, have a high defense capacity towards archetypical environmental stressors. However, the results also showed that induction of a stress defense may have a cost in regard...

  18. SBRC-Nottingham: sustainable routes to platform chemicals from C1 waste gases.

    Science.gov (United States)

    Burbidge, Alan; Minton, Nigel P

    2016-06-15

    Synthetic Biology Research Centre (SBRC)-Nottingham (www.sbrc-nottingham.ac.uk) was one of the first three U.K. university-based SBRCs to be funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and Engineering and Physical Sciences Research Council (EPSRC) as part of the recommendations made in the U.K.'s Synthetic Biology Roadmap. It was established in 2014 and builds on the pioneering work of the Clostridia Research Group (CRG) who have previously developed a range of gene tools for the modification of clostridial genomes. The SBRC is primarily focussed on the conversion of single carbon waste gases into platform chemicals with a particular emphasis on the use of the aerobic chassis Cupriavidus necator. © 2016 The Author(s).

  19. Comprehensive analysis of an Antarctic bacterial community with the adaptability of growth at higher temperatures than those in Antarctica.

    Science.gov (United States)

    Hosoi-Tanabe, Shoko; Zhang, Hongyan; Zhu, Daochen; Nagata, Shinichi; Ban, Syuhei; Imura, Satoshi

    2010-06-01

    To investigate the adaptability to higher temperatures of Antarctic microorganisms persisting in low temperature conditions for a long time, Antarctic lake samples were incubated in several selection media at 25 degrees C and 30 degrees C. The microorganisms did not grow at 30 degrees C; however, some of them grew at 25 degrees C, indicating that the bacteria in Antarctic have the ability to grow at a wide range of temperatures. Total DNA was extracted from these microorganisms and amplified using the bacteria-universal primers. The amplified fragments were cloned, and randomly selected 48 clones were sequenced. The sequenced clones showed high similarity to the alpha-subdivision of the Proteobacteria with specific affinity to the genus Agrobacterium, Caulobacter and Brevundimonas, the ss-subdivision of Proteobacteria with specific affinity to the genus Cupriavidus, and Bacillus of the phylum Firmicutes. These results showed the presence of universal genera, suggesting that the bacteria in the Antarctic lake were not specific to this environment.

  20. Biofunctionalized Nanofibers Using Arthrospira (Spirulina Biomass and Biopolymer

    Directory of Open Access Journals (Sweden)

    Michele Greque de Morais

    2015-01-01

    Full Text Available Electrospun nanofibers composed of polymers have been extensively researched because of their scientific and technical applications. Commercially available polyhydroxybutyrate (PHB and polyhydroxybutyrate-co-valerate (PHB-HV copolymers are good choices for such nanofibers. We used a highly integrated method, by adjusting the properties of the spinning solutions, where the cyanophyte Arthrospira (formally Spirulina was the single source for nanofiber biofunctionalization. We investigated nanofibers using PHB extracted from Spirulina and the bacteria Cupriavidus necator and compared the nanofibers to those made from commercially available PHB and PHB-HV. Our study assessed nanofiber formation and their selected thermal, mechanical, and optical properties. We found that nanofibers produced from Spirulina PHB and biofunctionalized with Spirulina biomass exhibited properties which were equal to or better than nanofibers made with commercially available PHB or PHB-HV. Our methodology is highly promising for nanofiber production and biofunctionalization and can be used in many industrial and life science applications.

  1. Isolation, characterization and development of bacteria in the Mine Gafsa for applications in bioremediation

    International Nuclear Information System (INIS)

    Heni, Sana

    2010-01-01

    Today pollution represents an important environmental problem. Bacterial ability to bioremediate many types of pollutants in different matrixes (soil, water, and air) have been widely acknowledged. The goal of the present work is to isolate from contaminated soil of Gafsa, in Tunisia, bacterial strains to evaluate their potential for bioremediation. Soil from the mining area of Gafsa was collected. Initially, many bacterial strains were isolated in TGY agar (Tryptone/Glucose/Yeast extract agar) based on the presence of pigments. The primary bacterial selection was performed using heavy metals and the minimal inhibitory concentrations (MICs) of a metal-resistant bacterium, Cupriavidus metallidurans CH34. Isolated metal-resistant bacterium was checked for its potential to resistant to gamma radiation. Selected strain, Micrococcus luteus S7, was assessed for its bioremediation potential of matrixes artificially contaminated under laboratory conditions for its future use in developing a bio product for contaminated soil inoculation.

  2. Mobile genetic elements, a key to microbial adaptation in extreme environments

    Science.gov (United States)

    van Houdt, Rob; Mijnendonckx, Kristel; Provoost, Ann; Monsieurs, Pieter; Mergeay, Max; Leys, Natalie

    To ensure well-being of the crew during manned spaceflight, continuous monitoring of different microbial contaminants in air, in water and on surfaces in the spacecraft is vital. Next to microorganisms originating mainly from human activity, strains from the closely related gen-era Cupriavidus and Ralstonia have been identified and isolated during numerous monitoring campaigns from different space-related environments. These strains have been found in the air of the Mars Exploration Rover assembly room, on the surface of the Mars Odyssey Orbiter and in different water sources from the International Space Station, Shuttle and Mir space station. In previous studies, we investigated the response of the model bacterium Cupriavidus metallidurans CH34 when cultured in the international space station (ISS) and space gravity and radiation simulation facilities, to understand it's ways to adapt to space flight conditions. It was also demonstrated that genetic rearrangements due to the movement of IS (insertion sequence) elements, enabled CH34 to adapt to toxic zinc concentrations, in space flight and on ground. In this study, we screened the full genome sequence of C. metallidurans CH34 for the presence of mobile genetic elements (MGEs), with the purpose to identified their putative role in adaptation to the new environments. Eleven genomic islands (GI) were identified in chro-mosome 1, three on the native plasmid pMOL28 and two on the native plasmid pMOL30. On the plasmids pMOL28 and pMOL30, all genes involved in the response to metals were located within GIs. Three of the GIs on chromosome 1 contained genes involved in the response to metals. Three GIs (CMGI-2, -3 and -4) on chromosome 1 belonged to the Tn4371 family, with CMGI-2 containing at least 25 genes involved in the degradation of toluene corresponding to CH34's ability to grow at expense of toluene, benzene or xylene as sole carbon source. CMGI-3 sheltered accessory genes involved in CO2 fixation and

  3. Poly(3-hydroxybutyrate production in an integrated electromicrobial setup: Investigation under stress-inducing conditions.

    Directory of Open Access Journals (Sweden)

    Israa Salem Al Rowaihi

    Full Text Available Poly(3-hydroxybutyrate (PHB, a biodegradable polymer, can be produced by different microorganisms. The PHB belongs to the family of polyhydroxyalkanoate (PHA that mostly accumulates as a granule in the cytoplasm of microorganisms to store carbon and energy. In this study, we established an integrated one-pot electromicrobial setup in which carbon dioxide is reduced to formate electrochemically, followed by sequential microbial conversion into PHB, using the two model strains, Methylobacterium extorquens AM1 and Cupriavidus necator H16. This setup allows to investigate the influence of different stress conditions, such as coexisting electrolysis, relatively high salinity, nutrient limitation, and starvation, on the production of PHB. The overall PHB production efficiency was analyzed in reasonably short reaction cycles typically as short as 8 h. As a result, the PHB formation was detected with C. necator H16 as a biocatalyst only when the electrolysis was operated in the same solution. The specificity of the source of PHB production is discussed, such as salinity, electricity, concurrent hydrogen production, and the possible involvement of reactive oxygen species (ROS.

  4. The Molecular Level Characterization of Biodegradable Polymers Originated from Polyethylene Using Non-Oxygenated Polyethylene Wax as a Carbon Source for Polyhydroxyalkanoate Production.

    Science.gov (United States)

    Johnston, Brian; Jiang, Guozhan; Hill, David; Adamus, Grazyna; Kwiecień, Iwona; Zięba, Magdalena; Sikorska, Wanda; Green, Matthew; Kowalczuk, Marek; Radecka, Iza

    2017-08-28

    There is an increasing demand for bio-based polymers that are developed from recycled materials. The production of biodegradable polymers can include bio-technological (utilizing microorganisms or enzymes) or chemical synthesis procedures. This report demonstrates the corroboration of the molecular structure of polyhydroxyalkanoates (PHAs) obtained by the conversion of waste polyethylene (PE) via non-oxygenated PE wax (N-PEW) as an additional carbon source for a bacterial species. The N-PEW, obtained from a PE pyrolysis reaction, has been found to be a beneficial carbon source for PHA production with Cupriavidus necator H16. The production of the N-PEW is an alternative to oxidized polyethylene wax (O-PEW) (that has been used as a carbon source previously) as it is less time consuming to manufacture and offers fewer industrial applications. A range of molecular structural analytical techniques were performed on the PHAs obtained; which included nuclear magnetic resonance (NMR) and electrospray ionisation tandem mass spectrometry (ESI-MS/MS). Our study showed that the PHA formed from N-PEW contained 3-hydroxybutyrate (HB) with 11 mol% of 3-hydroxyvalerate (HV) units.

  5. Poly(3-hydroxybutyrate) production in an integrated electromicrobial setup: Investigation under stress-inducing conditions

    Science.gov (United States)

    Al Rowaihi, Israa Salem; Paillier, Alexis; Rasul, Shahid; Karan, Ram; Grötzinger, Stefan Wolfgang; Eppinger, Jörg

    2018-01-01

    Poly(3-hydroxybutyrate) (PHB), a biodegradable polymer, can be produced by different microorganisms. The PHB belongs to the family of polyhydroxyalkanoate (PHA) that mostly accumulates as a granule in the cytoplasm of microorganisms to store carbon and energy. In this study, we established an integrated one-pot electromicrobial setup in which carbon dioxide is reduced to formate electrochemically, followed by sequential microbial conversion into PHB, using the two model strains, Methylobacterium extorquens AM1 and Cupriavidus necator H16. This setup allows to investigate the influence of different stress conditions, such as coexisting electrolysis, relatively high salinity, nutrient limitation, and starvation, on the production of PHB. The overall PHB production efficiency was analyzed in reasonably short reaction cycles typically as short as 8 h. As a result, the PHB formation was detected with C. necator H16 as a biocatalyst only when the electrolysis was operated in the same solution. The specificity of the source of PHB production is discussed, such as salinity, electricity, concurrent hydrogen production, and the possible involvement of reactive oxygen species (ROS). PMID:29698424

  6. Efficacy of various chemical disinfectants on biofilms formed in spacecraft potable water system components.

    Science.gov (United States)

    Wong, Wing C; Dudinsky, Lynn A; Garcia, Veronica M; Ott, Charlie M; Castro, Victoria A

    2010-07-01

    As the provision of potable water is critical for successful habitation of the International Space Station (ISS), life support systems were installed in December 2008 to recycle both humidity from the atmosphere and urine to conserve available water in the Station. In-flight pre-consumption testing from the dispensing needle at the Potable Water Dispenser (PWD) indicated that bacterial concentrations exceeded the current ISS specifications of 50 colony-forming units (CFU) ml(-1). Subsequent investigations revealed that a corrugated stainless steel flex hose upstream of the dispensing needle in the PWD was filled with nonsterile water and left at room temperature for more than 1 month before launch. To simulate biofilm formation that was suspected in the flight system, sterile flex hoses were seeded with a consortium of bacterial isolates previously recovered from other ISS water systems, including Ralstonia pickettii, Burkholderia multivorans, Caulobacter vibrioides, and Cupriavidus pauculus. After incubation for 5 days, the hoses were challenged with various chemical disinfectants including hydrogen peroxide (H2O2), colloidal silver, and buffered pH solutions to determine the ability of the disinfectants to decrease and maintain bacterial concentrations below ISS specifications. The disinfection efficacy over time was measured by collecting daily heterotrophic plate counts after exposure to the disinfectants. A single flush with either 6% H2O2 solution or a mixture of 3% H2O2 and 400 ppb colloidal silver effectively reduced the bacterial concentrations to <1 CFU ml(-1) for a period of up to 3 months.

  7. Evaluation of pyrrolidonyl arylamidase for the identification of nonfermenting Gram-negative rods.

    Science.gov (United States)

    Bombicino, Karina A; Almuzara, Marisa N; Famiglietti, Angela M R; Vay, Carlos

    2007-01-01

    To evaluate the activity of pyrrolidonyl arylamidase (PYR) for the differentiation and identification of nonfermenting gram negative rods (NFGNR), 293 isolates were tested. A 24 h culture of each test organism was prepared. From this a 108-109 cfu/mL suspension was added to 0.25 mL of sterile physiologic solution. A PYR disk was then added and the test was incubated for 30 minutes at 35-37 degrees C, at environmental atmosphere. Reading was done by adding 1 drop of cinnamaldehyde reagent. Strains of Acinetobacter baumannii, Acinetobacter haemolyticus, Alcaligenes faecalis, Bergeyella zoohelcum, Bordetella bronchiseptica, Bordetella hinzii, Brevundimonas diminuta, Brevundimonas vesicularis, Brucella ovis, Brucella spp., Brucella suis, Burkholderia cepacia complex, Moraxella catarrhalis, Moraxella lacunata, Moraxella nonliquefaciens, Moraxella osloensis, Oligella ureolytica, Pseudomonas alcaligenes, Pseudomonas mendocina, Pseudomonas pseudoalcaligenes, Pseudomonas putida, Pseudomonas stutzeri, Pseudomonas Vb3, Psychrobacter phenylpyruvicus, and Stenotrophomonas maltophilia were PYR negative. On the other hand Achromobacter piechaudii, Achromobacter denitrificans, Achromobacter xylosoxidans, Burkholderia gladioli, Chryseobacterium gleum-indologenes, Comamonas testosroni, Cupriavidus pauculus, Delftia acidovorans, Elizabethkingia meningoseptica, Myroides spp., Ochrobactrum anthropi, Pseudomonas oryzihabitans, Ralstonia pickettii, Rhizobium radiobacter, Shewanella spp., Sphingobacterium multivorum, Sphingobacterium spiritivorum, and Weeksella virosa were PYR positive. Finally, Acinetobacter lwoffii, Pseudomonas aeruginosa, Pseudomonas fluorescens, Roseomonas spp., and Sphingomonas paucimobilis-parapaucimobilis were PYR variable. PYR testing should be considered as a useful tool to facilitate the identification of NFGNR.

  8. Analysis of the bacterial diversity existing on animal hide and wool: development of a preliminary PCR-restriction fragment length polymorphism fingerprint database for identifying isolates.

    Science.gov (United States)

    Chen, Yu; Gao, Hongwei; Zhang, Yanming; Deng, Mingjun; Wu, Zhenxing; Zhu, Laihua; Duan, Qing; Xu, Biao; Liang, Chengzhu; Yue, Zhiqin; Xiao, Xizhi

    2012-01-01

    Twenty-one bacterial strains were isolated from imported cattle hide and rabbit wool using two types of media, nutrient broth, and nutrient broth with serum. The bacteria identified were Brevibacillus laterosporus, Leclercia adecarboxylata, Peptococcus niger, Bacillus circulans, Raoultella ornithinolytica, Bacillus subtilis, Bacillus cereus, Bacillus thermobacillus, Bacillus choshinensis, Bacillus sphaericus, Acinetobacter haemolyticus, Sphingomonas paucimobilis, Bacillus thuringiensis, Staphylococcus intermedius, Mycobacteria, Moraxella, Klebsiella pneumoniae, Ralstonia pickettii, Staphylococcus chromogenes, Comamonas testosteroni, and Cupriavidus pauculus. The 16s rDNA gene of each bacterium was amplified using the universal primers 27f and 1492r. The amplicons were digested with AvaI, BamHI, BgII, DraI, EcoRI, EcoRV, HindIII, HinfI, HpaI, PstI, SmaI, TaqII, XbaI, XmaI, AluI, XhoI, and PvuI individually. A specific fingerprint from the PCR-restriction fragment length polymorphism method based on 16s rDNA was obtained for each bacterium. The results showed that the method developed was useful not only for bacterial identification but also for the etiological investigation of pathogens in imported animal hair and wool.

  9. Metabolic engineering to expand the substrate spectrum of Pseudomonas putida toward sucrose.

    Science.gov (United States)

    Löwe, Hannes; Schmauder, Lukas; Hobmeier, Karina; Kremling, Andreas; Pflüger-Grau, Katharina

    2017-08-01

    Sucrose is an important disaccharide used as a substrate in many industrial applications. It is a major component of molasses, a cheap by-product of the sugar industry. Unfortunately, not all industrially relevant organisms, among them Pseudomonas putida, are capable of metabolizing sucrose. We chose a metabolic engineering approach to circumvent this blockage and equip P. putida with the activities necessary to consume sucrose. Therefore, we constructed a pair of broad-host range mini-transposons (pSST - sucrose splitting transposon), carrying either cscA, encoding an invertase able to split sucrose into glucose and fructose, or additionally cscB, encoding a sucrose permease. Introduction of cscA was sufficient to convey sucrose consumption and the additional presence of cscB had no further effect, though the sucrose permease was built and localized to the membrane. Sucrose was split extracellularly by the activity of the invertase CscA leaking out of the cell. The transposons were also used to confer sucrose consumption to Cupriavidus necator. Interestingly, in this strain, CscB acted as a glucose transporter, such that C. necator also gained the ability to grow on glucose. Thus, the pSST transposons are functional tools to extend the substrate spectrum of Gram-negative bacterial strains toward sucrose. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  10. Predicting metabolic pathways by sub-network extraction.

    Science.gov (United States)

    Faust, Karoline; van Helden, Jacques

    2012-01-01

    Various methods result in groups of functionally related genes obtained from genomes (operons, regulons, syntheny groups, and phylogenetic profiles), transcriptomes (co-expression groups) and proteomes (modules of interacting proteins). When such groups contain two or more enzyme-coding genes, graph analysis methods can be applied to extract a metabolic pathway that interconnects them. We describe here the way to use the Pathway extraction tool available on the NeAT Web server ( http://rsat.ulb.ac.be/neat/ ) to piece together the metabolic pathway from a group of associated, enzyme-coding genes. The tool identifies the reactions that can be catalyzed by the products of the query genes (seed reactions), and applies sub-graph extraction algorithms to extract from a metabolic network a sub-network that connects the seed reactions. This sub-network represents the predicted metabolic pathway. We describe here the pathway prediction process in a step-by-step way, give hints about the main parametric choices, and illustrate how this tool can be used to extract metabolic pathways from bacterial genomes, on the basis of two study cases: the isoleucine-valine operon in Escherichia coli and a predicted operon in Cupriavidus (Ralstonia) metallidurans.

  11. Study of biosorbents application on the treatment of radioactive liquid wastes with americium-241

    International Nuclear Information System (INIS)

    Borba, Tania Regina de

    2010-01-01

    The use of nuclear energy for many different purposes has been intensified and highlighted by the benefits that it provides. Medical diagnosis and therapy, agriculture, industry and electricity generation are examples of its application. However, nuclear energy generates radioactive wastes that require suitable treatment ensuring life and environmental safety. Biosorption and bioaccumulation represent an emergent alternative for the treatment of radioactive liquid wastes, providing volume reduction and physical state change. This work aimed to study biosorbents for the treatment of radioactive liquid wastes contaminated with americium-241 in order to reduce the volume and change the physical state from liquid to solid. The biosorbents evaluated were Saccharomyces cerevisiae immobilized in calcium alginate beads, inactivated and free cells of Saccharomyces cerevisiae, calcium alginate beads, Bacillus subtilis, Cupriavidus metallidurans and Ochrobactrum anthropi. The results were quite satisfactory, achieving 100% in some cases. The technique presented in this work may be useful and viable for implementing at the Waste Management Laboratory of IPEN - CNEN/SP in short term, since it is an easy and low cost method. (author)

  12. A new biological recovery approach for PHA using mealworm, Tenebrio molitor.

    Science.gov (United States)

    Murugan, Paramasivam; Han, Lizhu; Gan, Chee-Yuen; Maurer, Frans H J; Sudesh, Kumar

    2016-12-10

    Bacterial polyhydroxyalkanoates (PHA) are expensive partly due to the recovery and purification processes. Thus, many studies have been carried out in order to minimize the cost. Here we report on the use of mealworm, which is the larva of mealworm beetle (Tenebrio molitor) to recover PHA granules from Cupriavidus necator. Mealworms were shown to readily consume the freeze-dried C. necator cells and excrete the PHA granules in the form of whitish feces. Further purification using water, detergent and heat resulted in almost 100% pure PHA granules. Comparison with chloroform extraction showed no signs of reduction in the molecular weight and dispersion of the PHA molecules. Scanning electron microscopy and dynamic light scattering measurements revealed that the biologically recovered PHA granules retained their native spherical morphology. The PHA granules were subjected to a battery of tests to determine their purity and properties in comparison to the chloroform extracted PHA. This study has demonstrated the possibility of using mealworms as a biological agent to partially purify the PHA granules. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Identification of Inhibitors in Lignocellulosic Slurries and Determination of Their Effect on Hydrocarbon-Producing Microorganisms

    Directory of Open Access Journals (Sweden)

    Shihui Yang

    2018-04-01

    Full Text Available The aim of this work was to identify inhibitors in pretreated lignocellulosic slurries, evaluate high-throughput screening strategies, and investigate the impact of inhibitors on potential hydrocarbon-producing microorganisms. Compounds present in slurries that could inhibit microbial growth were identified through a detailed analysis of saccharified slurries by applying a combination of approaches of high-performance liquid chromatography, GC-MS, LC-DAD-MS, and ICP-MS. Several high-throughput assays were then evaluated to generate toxicity profiles. Our results demonstrated that Bioscreen C was useful for analyzing bacterial toxicity but not for yeast. AlamarBlue reduction assay can be a useful high-throughput assay for both bacterial and yeast strains as long as medium components do not interfere with fluorescence measurements. In addition, this work identified two major inhibitors (furfural and ammonium acetate for three potential hydrocarbon-producing bacterial species that include Escherichia coli, Cupriavidus necator, and Rhodococcus opacus PD630, which are also the primary inhibitors for ethanologens. This study was strived to establish a pipeline to quantify inhibitory compounds in biomass slurries and high-throughput approaches to investigate the effect of inhibitors on microbial biocatalysts, which can be applied for various biomass slurries or hydrolyzates generated through different pretreatment and enzymatic hydrolysis processes or different microbial candidates.

  14. Metagenomic identification of bacterioplankton taxa and pathways involved in microcystin degradation in lake erie.

    Directory of Open Access Journals (Sweden)

    Xiaozhen Mou

    Full Text Available Cyanobacterial harmful blooms (CyanoHABs that produce microcystins are appearing in an increasing number of freshwater ecosystems worldwide, damaging quality of water for use by human and aquatic life. Heterotrophic bacteria assemblages are thought to be important in transforming and detoxifying microcystins in natural environments. However, little is known about their taxonomic composition or pathways involved in the process. To address this knowledge gap, we compared the metagenomes of Lake Erie free-living bacterioplankton assemblages in laboratory microcosms amended with microcystins relative to unamended controls. A diverse array of bacterial phyla were responsive to elevated supply of microcystins, including Acidobacteria, Actinobacteria, Bacteroidetes, Planctomycetes, Proteobacteria of the alpha, beta, gamma, delta and epsilon subdivisions and Verrucomicrobia. At more detailed taxonomic levels, Methylophilales (mainly in genus Methylotenera and Burkholderiales (mainly in genera Bordetella, Burkholderia, Cupriavidus, Polaromonas, Ralstonia, Polynucleobacter and Variovorax of Betaproteobacteria were suggested to be more important in microcystin degradation than Sphingomonadales of Alphaproteobacteria. The latter taxa were previously thought to be major microcystin degraders. Homologs to known microcystin-degrading genes (mlr were not overrepresented in microcystin-amended metagenomes, indicating that Lake Erie bacterioplankton might employ alternative genes and/or pathways in microcystin degradation. Genes for xenobiotic metabolism were overrepresented in microcystin-amended microcosms, suggesting they are important in bacterial degradation of microcystin, a phenomenon that has been identified previously only in eukaryotic systems.

  15. Sophorolipid biosurfactants: Possible uses as antibacterial and antibiofilm agent.

    Science.gov (United States)

    Díaz De Rienzo, Mayri A; Banat, Ibrahim M; Dolman, Ben; Winterburn, James; Martin, Peter J

    2015-12-25

    Biosurfactants are amphipathic, surface-active molecules of microbial origin which accumulate at interfaces reducing interfacial tension and leading to the formation of aggregated micellular structures in solution. Some biosurfactants have been reported to have antimicrobial properties, the ability to prevent adhesion and to disrupt biofilm formation. We investigated antimicrobial properties and biofilm disruption using sophorolipids at different concentrations. Growth of Gram negative Cupriavidus necator ATCC 17699 and Gram positive Bacillus subtilis BBK006 were inhibited by sophorolipids at concentrations of 5% v/v with a bactericidal effect. Sophorolipids (5% v/v) were also able to disrupt biofilms formed by single and mixed cultures of B. subtilis BBK006 and Staphylococcus aureus ATCC 9144 under static and flow conditions, as was observed by scanning electron microscopy. The results indicated that sophorolipids may be promising compounds for use in biomedical application as adjuvants to other antimicrobial against some pathogens through inhibition of growth and/or biofilm disruption. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Endophytic bacteria from Piper tuberculatum Jacq.: isolation, molecular characterization, and in vitro screening for the control of Fusarium solani f. sp piperis, the causal agent of root rot disease in black pepper (Piper nigrum L.).

    Science.gov (United States)

    Nascimento, S B; Lima, A M; Borges, B N; de Souza, C R B

    2015-07-06

    Endophytic bacteria have been found to colonize internal tissues in many different plants, where they can have several beneficial effects, including defense against pathogens. In this study, we aimed to identify endophytic bacteria associated with roots of the tropical piperaceae Piper tuberculatum, which is known for its resistance to infection by Fusarium solani f. sp piperis, the causal agent of black pepper (Piper nigrum) root rot disease in the Amazon region. Based on 16S rRNA gene sequence analysis, we isolated endophytes belonging to 13 genera: Bacillus, Paenibacillus, Pseudomonas, Enterobacter, Rhizobium, Sinorhizobium, Agrobacterium, Ralstonia, Serratia, Cupriavidus, Mitsuaria, Pantoea, and Staphylococcus. The results showed that 56.52% of isolates were associated with the phylum Proteobacteria, which comprised α, β, and γ classes. Other bacteria were related to the phylum Firmicutes, including Bacillus, which was the most abundant genus among all isolates. Antagonistic assays revealed that Pt12 and Pt13 isolates, identified as Pseudomonas putida and Pseudomonas sp, respectively, were able to inhibit F. solani f. sp piperis growth in vitro. We describe, for the first time, the molecular identification of 23 endophytic bacteria from P. tuberculatum, among which two Pseudomonas species have the potential to control the pathogen responsible for root rot disease in black pepper in the Amazon region.

  17. The Legionella pneumophila GIG operon responds to gold and copper in planktonic and biofilm cultures.

    Directory of Open Access Journals (Sweden)

    Kathleen Jwanoswki

    Full Text Available Legionella pneumophila contaminates man-made water systems and creates numerous exposure risks for Legionnaires' Disease. Because copper/silver ionization is commonly used to control L. pneumophila, its mechanisms of metal response and detoxification are of significant interest. Here we describe an L. pneumophila operon with significant similarity to the GIG operon of Cupriavidus metallidurans. The Legionella GIG operon is present in a subset of strains and has been acquired as part of the ICE-βox 65-kB integrative conjugative element. We assessed GIG promoter activity following exposure of L. pneumophila to multiple concentrations of HAuCl4, CuSO4 and AgNO3. At 37°C, control stationary phase cultures exhibited GIG promoter activity. This activity increased significantly in response to 20 and 50uM HAuCl4 and CuSO4 but not in response to AgNO3. Conversely, at 26°C, cultures exhibited decreased promoter response to copper. GIG promoter activity was also induced by HAuCl4 or CuSO4 during early biofilm establishment at both temperatures. When an L. pneumophila GIG promoter construct was transformed into E. coli DH5α, cultures showed baseline expression levels that did not increase following metal addition. Analysis of L. pneumophila transcriptional regulatory mutants suggested that GIG up-regulation in the presence of metal ions may be influenced by the stationary phase sigma factor, RpoS.

  18. Effect of red clay on diesel bioremediation and soil bacterial community.

    Science.gov (United States)

    Jung, Jaejoon; Choi, Sungjong; Hong, Hyerim; Sung, Jung-Suk; Park, Woojun

    2014-08-01

    Red clay is a type of soil, the red color of which results from the presence of iron oxide. It is considered an eco-friendly material, with many industrial, cosmetic, and architectural uses. A patented method was applied to red clay in order to change its chemical composition and mineral bioavailability. The resulting product was designated processed red clay. This study evaluates the novel use of red clay and processed red clay as biostimulation agents in diesel-contaminated soils. Diesel biodegradation was enhanced in the presence of red clay and processed red clay by 4.9- and 6.7-fold, respectively, and the number of culturable bacterial cells was correlated with the amount of diesel biodegradation. The growth of Acinetobacter oleivorans DR1, Pseudomonas putida KT2440, and Cupriavidus necator was promoted by both types of red clays. Culture-independent community analysis determined via barcoded pyrosequencing indicated that Nocardioidaceae, Xanthomonadaceae, Pseudomonadaceae, and Caulobacteraceae were enriched by diesel contamination. Bacterial strain isolation from naphthalene- and liquid paraffin-amended media was affiliated with enriched taxa based on 16S rRNA gene sequence identity. We suggest that the biostimulating mechanism of red clay and processed red clay is able to support bacterial growth without apparent selection for specific bacterial species.

  19. Impact of metal stress on the production of secondary metabolites in Pteris vittata L. and associated rhizosphere bacterial communities.

    Science.gov (United States)

    Pham, Hoang Nam; Michalet, Serge; Bodillis, Josselin; Nguyen, Tien Dat; Nguyen, Thi Kieu Oanh; Le, Thi Phuong Quynh; Haddad, Mohamed; Nazaret, Sylvie; Dijoux-Franca, Marie-Geneviève

    2017-07-01

    Plants adapt to metal stress by modifying their metabolism including the production of secondary metabolites in plant tissues. Such changes may impact the diversity and functions of plant associated microbial communities. Our study aimed to evaluate the influence of metals on the secondary metabolism of plants and the indirect impact on rhizosphere bacterial communities. We then compared the secondary metabolites of the hyperaccumulator Pteris vittata L. collected from a contaminated mining site to a non-contaminated site in Vietnam and identified the discriminant metabolites. Our data showed a significant increase in chlorogenic acid derivatives and A-type procyanidin in plant roots at the contaminated site. We hypothesized that the intensive production of these compounds could be part of the antioxidant defense mechanism in response to metals. In parallel, the structure and diversity of bulk soil and rhizosphere communities was studied using high-throughput sequencing. The results showed strong differences in bacterial composition, characterized by the dominance of Proteobacteria and Nitrospira in the contaminated bulk soil, and the enrichment of some potential human pathogens, i.e., Acinetobacter, Mycobacterium, and Cupriavidus in P. vittata's rhizosphere at the mining site. Overall, metal pollution modified the production of P. vittata secondary metabolites and altered the diversity and structure of bacterial communities. Further investigations are needed to understand whether the plant recruits specific bacteria to adapt to metal stress.

  20. A New Metal Binding Domain Involved in Cadmium, Cobalt and Zinc Transport

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Aaron T. [Northwestern Univ., Evanston, IL (United States); Barupala, Dulmini [Wayne State Univ., Detroit, MI (United States); Stemmler, Timothy L. [Wayne State Univ., Detroit, MI (United States); Rosenzweig, Amy C. [Northwestern Univ., Evanston, IL (United States)

    2015-07-20

    In the P1B-ATPases, which couple cation transport across membranes to ATP hydrolysis, are central to metal homeostasis in all organisms. An important feature of P1B-ATPases is the presence of soluble metal binding domains (MBDs) that regulate transport activity. Only one type of MBD has been characterized extensively, but bioinformatics analyses indicate that a diversity of MBDs may exist in nature. Here we report the biochemical, structural and functional characterization of a new MBD from the Cupriavidus metallidurans P1B-4-ATPase CzcP (CzcP MBD). The CzcP MBD binds two Cd2+, Co2+ or Zn2+ ions in distinct and unique sites and adopts an unexpected fold consisting of two fused ferredoxin-like domains. Both in vitro and in vivo activity assays using full-length CzcP, truncated CzcP and several variants indicate a regulatory role for the MBD and distinct functions for the two metal binding sites. Moreover, these findings elucidate a previously unknown MBD and suggest new regulatory mechanisms for metal transport by P1B-ATPases.

  1. The Legionella pneumophila GIG operon responds to gold and copper in planktonic and biofilm cultures.

    Science.gov (United States)

    Jwanoswki, Kathleen; Wells, Christina; Bruce, Terri; Rutt, Jennifer; Banks, Tabitha; McNealy, Tamara L

    2017-01-01

    Legionella pneumophila contaminates man-made water systems and creates numerous exposure risks for Legionnaires' Disease. Because copper/silver ionization is commonly used to control L. pneumophila, its mechanisms of metal response and detoxification are of significant interest. Here we describe an L. pneumophila operon with significant similarity to the GIG operon of Cupriavidus metallidurans. The Legionella GIG operon is present in a subset of strains and has been acquired as part of the ICE-βox 65-kB integrative conjugative element. We assessed GIG promoter activity following exposure of L. pneumophila to multiple concentrations of HAuCl4, CuSO4 and AgNO3. At 37°C, control stationary phase cultures exhibited GIG promoter activity. This activity increased significantly in response to 20 and 50uM HAuCl4 and CuSO4 but not in response to AgNO3. Conversely, at 26°C, cultures exhibited decreased promoter response to copper. GIG promoter activity was also induced by HAuCl4 or CuSO4 during early biofilm establishment at both temperatures. When an L. pneumophila GIG promoter construct was transformed into E. coli DH5α, cultures showed baseline expression levels that did not increase following metal addition. Analysis of L. pneumophila transcriptional regulatory mutants suggested that GIG up-regulation in the presence of metal ions may be influenced by the stationary phase sigma factor, RpoS.

  2. Light scattering on PHA granules protects bacterial cells against the harmful effects of UV radiation.

    Science.gov (United States)

    Slaninova, Eva; Sedlacek, Petr; Mravec, Filip; Mullerova, Lucie; Samek, Ota; Koller, Martin; Hesko, Ondrej; Kucera, Dan; Marova, Ivana; Obruca, Stanislav

    2018-02-01

    Numerous prokaryotes accumulate polyhydroxyalkanoates (PHA) in the form of intracellular granules. The primary function of PHA is the storage of carbon and energy. Nevertheless, there are numerous reports that the presence of PHA granules in microbial cells enhances their stress resistance and fitness when exposed to various stress factors. In this work, we studied the protective mechanism of PHA granules against UV irradiation employing Cupriavidus necator as a model bacterial strain. The PHA-accumulating wild type strain showed substantially higher UV radiation resistance than the PHA non-accumulating mutant. Furthermore, the differences in UV-Vis radiation interactions with both cell types were studied using various spectroscopic approaches (turbidimetry, absorption spectroscopy, and nephelometry). Our results clearly demonstrate that intracellular PHA granules efficiently scatter UV radiation, which provides a substantial UV-protective effect for bacterial cells and, moreover, decreases the intracellular level of reactive oxygen species in UV-challenged cells. The protective properties of the PHA granules are enhanced by the fact that granules specifically bind to DNA, which in turn provides shield-like protection of DNA as the most UV-sensitive molecule. To conclude, the UV-protective action of PHA granules adds considerable value to their primary storage function, which can be beneficial in numerous environments.

  3. The geographical patterns of symbiont diversity in the invasive legume Mimosa pudica can be explained by the competitiveness of its symbionts and by the host genotype.

    Science.gov (United States)

    Melkonian, Rémy; Moulin, Lionel; Béna, Gilles; Tisseyre, Pierre; Chaintreuil, Clémence; Heulin, Karine; Rezkallah, Naïma; Klonowska, Agnieszka; Gonzalez, Sophie; Simon, Marcelo; Chen, Wen-Ming; James, Euan K; Laguerre, Gisèle

    2014-07-01

    Variations in the patterns of diversity of symbionts have been described worldwide on Mimosa pudica, a pan-tropical invasive species that interacts with both α and β-rhizobia. In this study, we investigated if symbiont competitiveness can explain these variations and the apparent prevalence of β- over α-rhizobia. We developed an indirect method to measure the proportion of nodulation against a GFP reference strain and tested its reproducibility and efficiency. We estimated the competitiveness of 54 strains belonging to four species of β-rhizobia and four of α-rhizobia, and the influence of the host genotype on their competitiveness. Our results were compared with biogeographical patterns of symbionts and host varieties. We found: (i) a strong strain effect on competitiveness largely explained by the rhizobial species, with Burkholderia phymatum being the most competitive species, followed by B. tuberum, whereas all other species shared similar and reduced levels of competitiveness; (ii) plant genotype can increase the competitiveness of Cupriavidus taiwanensis. The latter data support the likelihood of the strong adaptation of C. taiwanensis with the M. pudica var. unijuga and help explain its prevalence as a symbiont of this variety over Burkholderia species in some environments, most notably in Taiwan. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

  4. Properties of PHA bi-, ter-, and quarter-polymers containing 4-hydroxybutyrate monomer units.

    Science.gov (United States)

    Zhila, Natalia; Shishatskaya, Ekaterina

    2018-05-01

    The present study investigates physicochemical, mechanical, and biological properties of polyhydroxyalkanoate (PHA) copolymers containing 4-hydroxybutyrate (4HB) synthesized in Cupriavidus eutrophus B10646 culture. In poly(3-hydroxybutyrate/4-hydroxybutyrate) [P(3HB/4HB)] bipolymers, 4HB varied between 10.4 and 75.0 mol%; in poly(3-hydroxybutyrate/3-hydroxyvalerate/4-hydroxybutyrate) terpolymers, 4HB constituted 28.7-55.6 mol%; and in poly(3-hydroxybutyrate/3-hydroxyvalerate/4-hydroxybutyrate/3-hydroxyhexanoate) quaterpolymers, 4HB varied between 9.3 and 13.3 mol%. The degree of crystallinity of P(3HB/4HB) copolymers decreased consistently with an increase in 4HB content, reaching 38%. The incorporation of 3-hydroxyvalerate and 3-hydroxyhexanoate into copolymers enhanced that effect. The effect of 4HB monomer units on temperature properties of copolymers was exhibited as lowering of the melting temperature and crystallization temperature, which improved the processing-related properties of the copolymers. All copolymers containing 4HB showed enhanced elongation at break compared to poly(3-hydroxybutyrate). Polymer films prepared from PHAs with different chemical composition had similar microstructure and porosity and had no toxic effect on mouse fibroblast NIH 3 T3 cells, proving their high biocompatibility. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Effect of ionizing radiation on solid and water solution Penicillin G

    International Nuclear Information System (INIS)

    Ben Salem, I.; Amine, Kh.M.; Mabrouk, Y.; Saidi, M.; Mezni, M; Boulila, N; Hafez, E

    2015-01-01

    Penicillin G is a conventional antibiotic used for treatment of different kinds of infectious diseases. Due to its huge quantity production and resistance to biodegradability, this molecule has been a serious concern for clinicians and environmentalists. In this study, the effect of ionizing radiation on the penicillin G powder and in water solution was investigated. The Nuclear Magnetic Resonance (NMR) and fourier transform infrared spectroscopy (FTIR) analysis showed that the ionizing radiation at 50 kGy has no effect on the integrity of solid Penicillin G. The anti-microbial assays revealed that the activity of irradiated solid Penicillin G did not reduce and was stable after storage for one month. Ionizing radiation at 50 kGy led to degradation of water solution Penicillin G. The complete disappear of peaks observed in the control sample confirmed the broken of β-lactam ring, the decarboxylation and cleavage of the thiazolidine ring. The product issued from the irradiation of Penicillin G, was completely removed by the bacterium Cupriavidus.metallidurans. Thus, the ionizing irradiation followed by a biological treatment was very effective method for removing of Penicillin G antibiotics residuals from water solution.

  6. Analysis and optimization of triacylglycerol synthesis in novel oleaginous Rhodococcus and Streptomyces strains isolated from desert soil.

    Science.gov (United States)

    Röttig, Annika; Hauschild, Philippa; Madkour, Mohamed H; Al-Ansari, Ahmed M; Almakishah, Naief H; Steinbüchel, Alexander

    2016-05-10

    As oleaginous microorganisms represent an upcoming novel feedstock for the biotechnological production of lipids or lipid-derived biofuels, we searched for novel, lipid-producing strains in desert soil. This was encouraged by the hypothesis that neutral lipids represent an ideal storage compound, especially under arid conditions, as several animals are known to outlast long periods in absence of drinking water by metabolizing their body fat. Ten lipid-accumulating bacterial strains, affiliated to the genera Bacillus, Cupriavidus, Nocardia, Rhodococcus and Streptomyces, were isolated from arid desert soil due to their ability to synthesize poly(β-hydroxybutyrate), triacylglycerols or wax esters. Particularly two Streptomyces sp. strains and one Rhodococcus sp. strain accumulate significant amounts of TAG under storage conditions under optimized cultivation conditions. Rhodococcus sp. A27 and Streptomyces sp. G49 synthesized approx. 30% (w/w) fatty acids from fructose or cellobiose, respectively, while Streptomyces isolate G25 reached a cellular fatty acid content of nearly 50% (w/w) when cultivated with cellobiose. The stored triacylglycerols were composed of 30-40% branched fatty acids, such as anteiso-pentadecanoic or iso-hexadecanoic acid. To date, this represents by far the highest lipid content described for streptomycetes. A biotechnological production of such lipids using (hemi)cellulose-derived raw material could be used to obtain sustainable biodiesel with a high proportion of branched-chain fatty acids to improve its cold-flow properties and oxidative stability. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Cloning and Expression of the PHA Synthase Gene From a Locally Isolated Chromobacterium sp. USM2

    Directory of Open Access Journals (Sweden)

    Bhubalan, K.

    2010-01-01

    Full Text Available Chromobacterium sp. USM2, a locally isolated bacterium was found to synthesize poly(3-hydroxybutyrate-co-3-hydroxyvalerate, P(3HB-co-3HV copolymer with high 3HV monomer composition. The PHA synthase gene was cloned and expressed in Cupriavidus necator PHB¯4 to investigate the possibilities of incorporating other monomer. The recombinant successfully incorporated 3-hydroxyhexanoate (3HHx monomer when fed with crude palm kernel oil (CPKO as the sole carbon source. Approximately 63 ± 2 wt% of P(3HB-co-3HHx copolymer with 4 mol% of 3HHx was synthesized from 5 g/L of oil after 48 h of cultivation. In addition, P(3HB-co-3HV-co-3HHx terpolymer with 9 mol% 3HV and 4 mol% 3HHx could be synthesized with a mixture of CPKO and sodium valerate. The presence of 3HV and 3HHx monomers in the copolymer and terpolymer was further confirmed with +H-NMR analysis. This locally isolated PHA synthase has demonstrated its ability to synthesize P(3HB-co-3HHx copolymer from a readily available and renewable carbon source; CPKO, without the addition of 3HHx precursors.

  8. Biorefinery production of poly-3-hydroxybutyrate using waste office paper hydrolysate as feedstock for microbial fermentation.

    Science.gov (United States)

    Neelamegam, Annamalai; Al-Battashi, Huda; Al-Bahry, Saif; Nallusamy, Sivakumar

    2018-01-10

    Waste paper, a major fraction of municipal solid waste, has a potential to serve as renewable feedstock for the biorefineries of fuels, chemicals and materials due to rich in cellulose and abundant at low cost. This study evaluates the possibility of waste office paper (WOP) to serve as a potential feedstock for the biorefinery production of poly (3-hydroxybutyrate). In this study, the WOP was pretreated, enzymatically saccharified and the hydrolysate was used for PHB production. The hydrolysate mainly consists of glucose (22.70g/L) and xylose (1.78g/L) and the corresponding sugar yield was about 816mg/g. Ammonium sulphate and C/N ratio 20 were identified as most favorable for high yield of PHB. The batch fermentation of Cupriavidus necator using the pretreated WOP hydrolysate resulted in cell biomass, PHB production and PHB content of 7.74g/L, 4.45g/L and 57.52%, respectively. The volumetric productivity and yield achieved were 0.061g/L/h and 0.210g/g sugar, respectively. The results suggested that WOP could be a potential alternative feedstock for the biorefinery production of bioplastics. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Production of green biodegradable plastics of poly(3-hydroxybutyrate) from renewable resources of agricultural residues.

    Science.gov (United States)

    Dahman, Yaser; Ugwu, Charles U

    2014-08-01

    This work describes potential opportunities for utilization of agro-industrial residues to produce green biodegradable plastics of poly(3-hydroxybutyrate) (PHB). Wheat straws were examined with good efficacy of carbon substrates using Cupriavidus necator. Production was examined in separate hydrolysis and fermentation (SHF) in the presence and absence of WS hydrolysis enzymes, and in simultaneous saccharification and fermentation (SSF) with enzymes. Results showed that production of PHB in SSF was more efficient in terms of viable cell count, cell dry weight, and PHB production and yield compared to those of SHF and glucose-control cultures. While glucose control experiment produced 4.6 g/L PHB; SSF produced 10.0 g/L compared to 7.1 g/L in SHF when utilizing enzymes during WS hydrolysis. Results showed that most of sugars produced during the hydrolysis were consumed in SHF (~98 %) compared to 89.2 % in SSF. Results also demonstrated that a combination of glucose and xylose can compensate for the excess carbon required for enhancing PHB production by C. necator. However, higher concentration of sugars at the beginning of fermentation in SHF can lead to cell inhibition and consequently catabolite repressions. Accordingly, results demonstrated that the gradual release of sugars in SSF enhanced PHB production. Moreover, the presence of sugars other than glucose and xylose can eliminate PHB degradation in medium of low carbon substrate concentrations in SSF.

  10. Geobiological Cycling of Gold: From Fundamental Process Understanding to Exploration Solutions

    Directory of Open Access Journals (Sweden)

    Frank Reith

    2013-11-01

    Full Text Available Microbial communities mediating gold cycling occur on gold grains from (sub-tropical, (semi-arid, temperate and subarctic environments. The majority of identified species comprising these biofilms are β-Proteobacteria. Some bacteria, e.g., Cupriavidus metallidurans, Delftia acidovorans and Salmonella typhimurium, have developed biochemical responses to deal with highly toxic gold complexes. These include gold specific sensing and efflux, co-utilization of resistance mechanisms for other metals, and excretion of gold-complex-reducing siderophores that ultimately catalyze the biomineralization of nano-particulate, spheroidal and/or bacteriomorphic gold. In turn, the toxicity of gold complexes fosters the development of specialized biofilms on gold grains, and hence the cycling of gold in surface environments. This was not reported on isoferroplatinum grains under most near-surface environments, due to the lower toxicity of mobile platinum complexes. The discovery of gold-specific microbial responses can now drive the development of geobiological exploration tools, e.g., gold bioindicators and biosensors. Bioindicators employ genetic markers from soils and groundwaters to provide information about gold mineralization processes, while biosensors will allow in-field analyses of gold concentrations in complex sampling media.

  11. Biological Production of a Hydrocarbon Fuel Intermediate Polyhydroxybutyrate (Phb) from a Process Relevant Lignocellulosic Derived Sugar

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei; Mohagheghi, Ali; Mittal, Ashutosh; Pilath, Heidi; Johnson, David K.

    2015-03-22

    PHAs are synthesized by many microorganisms to serve as intracellular carbon storage molecules. In some bacterial strains, PHB can account for up to 80% of cell mass. In addition to its application in the packaging sector, PHB also has great potential as an intermediate in the production of hydrocarbon fuels. PHB can be thermally depolymerized and decarboxylated to propene which can be upgraded to hydrocarbon fuels via commercial oligomerization technologies. In recent years a great effort has been made in bacterial production of PHB, yet the production cost of the polymer is still much higher than conventional petrochemical plastics. The high cost of PHB is because the cost of the substrates can account for as much as half of the total product cost in large scale fermentation. Thus searching for cheaper and better substrates is very necessary for PHB production. In this study, we demonstrate production of PHB by Cupriavidus necator from a process relevant lignocellulosic derived sugar stream, i.e., saccharified hydrolysate slurry from pretreated corn stover. Good cell growth was observed on slurry saccharified with advanced enzymes and 40~60% of PHB was accumulated in the cells. The mechanism of inhibition in the toxic hydrolysate generated by pretreatment and saccharification of biomass, will be discussed.

  12. Direct Production of Propene from the Thermolysis of Poly(..beta..-hydroxybutyrate)

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, Ashutosh; Pilath, Heidi M.; Johnson, David K.

    2015-03-22

    To transform biomass components into hydrocarbon fuels it is clear that there are two main transformations that need to occur, i.e., deoxygenation and carbon chain extension. The potential routes for decreasing the oxygen content of biomass intermediates include dehydration, hydrodeoxygenation and decarboxylation. One route that is examined here is the conversion of polyhydroxyalkanoates (PHA) to alkenes that would be intermediates to hydrocarbon fuels.Thermal breakdown of PHA proceeds via an intermediate carboxylic acid, which can then be decarboxylated to an alkene. Oligomerization of alkenes by well-known commercial technologies would permit production of a range of hydrocarbon fuels from a carbohydrate derived intermediate. Moreover, polyhydroxybutyrate (PHB) can be produced in Cupriavidus necator (formerly known as Ralstonia eutropha) and Alcaligenes eutrophus on a variety of carbon sources including glucose, fructose and glycerol with PHB accumulation reaching 75 percent of dry cell mass. We conducted thermal conversion of PHB and pure crotonic acid (CA), the intermediate carboxylic acid produced by thermal depolymerization of PHB, in a flow-through reactor. The results of initial experiments on the thermal conversion of CA showed that up to 75 mole percent yields of propene could be achieved by optimizing the residence time and temperature of the reactor. Further experiments are being investigated to optimize the reactor parameters and enhance propene yields via thermal conversion of PHB.

  13. The presence of PHB granules in cytoplasm protects non-halophilic bacterial cells against the harmful impact of hypertonic environments.

    Science.gov (United States)

    Obruca, Stanislav; Sedlacek, Petr; Mravec, Filip; Krzyzanek, Vladislav; Nebesarova, Jana; Samek, Ota; Kucera, Dan; Benesova, Pavla; Hrubanova, Kamila; Milerova, Miluse; Marova, Ivana

    2017-10-25

    Numerous prokaryotes accumulate polyhydroxybutyrate (PHB) intracellularly as a storage material. It has also been proposed that PHB accumulation improves bacterial stress resistance. Cupriavidus necator and its PHB non-accumulating mutant were employed to investigate the protective role of PHB under hypertonic conditions. The presence of PHB granules enhanced survival of the bacteria after exposure to hypertonic conditions. Surprisingly, when coping with such conditions, the bacteria did not utilize PHB to harvest carbon or energy, suggesting that, in the osmotic upshock of C. necator, the protective mechanism of PHB granules is not associated with their hydrolysis. The presence of PHB granules influenced the overall properties of the cells, since challenged PHB-free cells underwent massive plasmolysis accompanied by damage to the cell membrane and the leakage of cytoplasm content, while no such effects were observed in PHB containing bacteria. Moreover, PHB granules demonstrated "liquid-like" properties indicating that they can partially repair and stabilize cell membranes by plugging small gaps formed during plasmolysis. In addition, the level of dehydration and changes in intracellular pH in osmotically challenged cells were less pronounced for PHB-containing cultures, demonstrating the important role of PHB for bacterial survival under hyperosmotic conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Biological Production of a Hydrocarbon Fuel Intermediate Polyhydroxybutyrate (PHB) from a Process Relevant Lignocellulosic Derived Sugar (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Wang, W.; Mittal, A.; Mohagheghi, A.; Johnson, D. K.

    2014-04-01

    PHAs are synthesized by many microorganisms to serve as intracellular carbon storage molecules. In some bacterial strains, PHB can account for up to 80% of cell mass. In addition to its application in the packaging sector, PHB also has great potential as an intermediate in the production of hydrocarbon fuels. PHB can be thermally depolymerized and decarboxylated to propene which can be upgraded to hydrocarbon fuels via commercial oligomerization technologies. Cupriavidus necator is the microorganism that has been most extensively studied and used for PHB production on an industrial scale; However the substrates used for producing PHB are mainly fructose, glucose, sucrose, fatty acids, glycerol, etc., which are expensive. In this study, we demonstrate production of PHB from a process relevant lignocellulosic derived sugar stream, i.e., saccharified slurry from pretreated corn stover. The strain was first investigated in shake flasks for its ability to utilize glucose, xylose and acetate. In addition, the strain was also grown on pretreated lignocellulose hydrolyzate slurry and evaluated in terms of cell growth, sugar utilization, PHB accumulation, etc. The mechanism of inhibition in the toxic hydrolysate generated by the pretreatment and saccharification process of biomass, was also studied.

  15. Complex sputum microbial composition in patients with pulmonary tuberculosis

    Science.gov (United States)

    2012-01-01

    Background An increasing number of studies have implicated the microbiome in certain diseases, especially chronic diseases. In this study, the bacterial communities in the sputum of pulmonary tuberculosis patients were explored. Total DNA was extracted from sputum samples from 31 pulmonary tuberculosis patients and respiratory secretions of 24 healthy participants. The 16S rRNA V3 hyper-variable regions were amplified using bar-coded primers and pyro-sequenced using Roche 454 FLX. Results The results showed that the microbiota in the sputum of pulmonary tuberculosis patients were more diverse than those of healthy participants (ppulmonary tuberculosis patients and 17 of which were found in healthy participants. Furthermore, many foreign bacteria, such as Stenotrophomonas, Cupriavidus, Pseudomonas, Thermus, Sphingomonas, Methylobacterium, Diaphorobacter, Comamonas, and Mobilicoccus, were unique to pulmonary tuberculosis patients. Conclusions This study concluded that the microbial composition of the respiratory tract of pulmonary tuberculosis patients is more complicated than that of healthy participants, and many foreign bacteria were found in the sputum of pulmonary tuberculosis patients. The roles of these foreign bacteria in the onset or development of pulmonary tuberculosis shoud be considered by clinicians. PMID:23176186

  16. Effects of cosmetics on the skin microbiome of facial cheeks with different hydration levels.

    Science.gov (United States)

    Lee, Hyo Jung; Jeong, Sang Eun; Lee, Soyoun; Kim, Sungwoo; Han, Hyuntak; Jeon, Che Ok

    2018-04-01

    Basic cosmetics was used by volunteers belonging to high (HHG) and low (LHG) hydration groups for 4 weeks, and bacterial communities and biophysical parameters in facial skin were analyzed. Hydration level increases and transepidermal water loss and roughness decreases were observed in both groups after cosmetic use. Bacterial diversity was greater in LHG than HHG, and increased after cosmetic use in both groups. Bray-Curtis dissimilarities that were higher in LHG than HHG increased in HHG after cosmetic use, whereas they decreased in LHG. The phyla Actinobacteria, Proteobacteria, Firmicutes, and Bacteroidetes and the genera Propionibacterium, Ralstonia, Burkholderia, Staphylococcus, Corynebacterium, Cupriavidus, and Pelomonas were identified as common groups and they were not significantly different between LHG and HHG except for Propionibacterium that was more abundant in HHG. After cosmetic use, Propionibacterium, Staphylococcus, and Corynebacterium decreased, whereas Ralstonia, not a core genus, increased, as did KEGG categories of lipid metabolism and xenobiotics biodegradation and metabolism, suggesting that Ralstonia in skin may have the ability to metabolize cosmetics components. Bacterial communities after cosmetic use were different from those in both LHG and HHG before the cosmetic use, indicating that bacterial communities in LHG were not shifted to resemble those in HHG by cosmetics use. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  17. Poly(3-hydroxybutyrate) production in an integrated electromicrobial setup: Investigation under stress-inducing conditions

    KAUST Repository

    Al Rowaihi, Israa Salem

    2018-04-26

    Poly(3-hydroxybutyrate) (PHB), a biodegradable polymer, can be produced by different microorganisms. The PHB belongs to the family of polyhydroxyalkanoate (PHA) that mostly accumulates as a granule in the cytoplasm of microorganisms to store carbon and energy. In this study, we established an integrated one-pot electromicrobial setup in which carbon dioxide is reduced to formate electrochemically, followed by sequential microbial conversion into PHB, using the two model strains, Methylobacterium extorquens AM1 and Cupriavidus necator H16. This setup allows to investigate the influence of different stress conditions, such as coexisting electrolysis, relatively high salinity, nutrient limitation, and starvation, on the production of PHB. The overall PHB production efficiency was analyzed in reasonably short reaction cycles typically as short as 8 h. As a result, the PHB formation was detected with C. necator H16 as a biocatalyst only when the electrolysis was operated in the same solution. The specificity of the source of PHB production is discussed, such as salinity, electricity, concurrent hydrogen production, and the possible involvement of reactive oxygen species (ROS).

  18. Evaluating the Metal Tolerance Capacity of Microbial Communities Isolated from Alberta Oil Sands Process Water.

    Directory of Open Access Journals (Sweden)

    Mathew L Frankel

    Full Text Available Anthropogenic activities have resulted in the intensified use of water resources. For example, open pit bitumen extraction by Canada's oil sands operations uses an estimated volume of three barrels of water for every barrel of oil produced. The waste tailings-oil sands process water (OSPW-are stored in holding ponds, and present an environmental concern as they are comprised of residual hydrocarbons and metals. Following the hypothesis that endogenous OSPW microbial communities have an enhanced tolerance to heavy metals, we tested the capacity of planktonic and biofilm populations from OSPW to withstand metal ion challenges, using Cupriavidus metallidurans, a known metal-resistant organism, for comparison. The toxicity of the metals toward biofilm and planktonic bacterial populations was determined by measuring the minimum biofilm inhibitory concentrations (MBICs and planktonic minimum inhibitory concentrations (MICs using the MBEC ™ assay. We observed that the OSPW community and C. metallidurans had similar tolerances to 22 different metals. While thiophillic elements (Te, Ag, Cd, Ni were found to be most toxic, the OSPW consortia demonstrated higher tolerance to metals reported in tailings ponds (Al, Fe, Mo, Pb. Metal toxicity correlated with a number of physicochemical characteristics of the metals. Parameters reflecting metal-ligand affinities showed fewer and weaker correlations for the community compared to C. metallidurans, suggesting that the OSPW consortia may have developed tolerance mechanisms toward metals present in their environment.

  19. Enteropathogenic Bacteria Contamination of Unchlorinated Drinking Water in Korea, 2010

    Science.gov (United States)

    Lee, Si Won; Lee, Do Kyung; An, Hyang Mi; Cha, Min Kyeong; Kim, Kyung Jae

    2011-01-01

    Objectives The purpose of this study was to assess the microbiological quality of unchlorinated drinking water in Korea, 2010. One hundred and eighty unchlorinated drinking water samples were collected from various sites in Seoul and Gyeonggi province. Methods To investigate bacterial presence, the pour plate method was used with cultures grown on selective media for total bacteria, total coliforms, and Staphylococcus spp., respectively. Results In the 180 total bacteria investigation, 72 samples from Seoul and 33 samples from Gyeonggi province were of an unacceptable quality (>102 CFU/mL). Of all the samples tested, total coliforms were detected in 28 samples (15.6%) and Staphylococcus spp. in 12 samples (6.7%). Most of the coliform isolates exhibited high-level resistance to cefazolin (88.2%), cefonicid (64.7%) and ceftazidime (20.6%). In addition, Staphylococcus spp. isolates exhibited high-level resistance to mupirocin (42%). Species of Pseudomonas, Acinetobacter, Cupriavidus, Hafnia, Rahnella, Serratia, and Yersinia were isolated from the water samples. Conclusions The results of this study suggest that consumption of unchlorinated drinking water could represent a notable risk to the health of consumers. As such, there is need for continuous monitoring of these water sources and to establish standards. PMID:22216417

  20. Extensive cultivation of soil and water samples yields various pathogens in patients with cystic fibrosis but not Burkholderia multivorans.

    Science.gov (United States)

    Peeters, Charlotte; Depoorter, Eliza; Praet, Jessy; Vandamme, Peter

    2016-11-01

    While the epidemiology of Burkholderia cepacia complex (Bcc) bacteria in cystic fibrosis (CF) patients suggests that Burkholderia multivorans is acquired from environmental sources, this species has rarely been isolated from soil and water samples. Multiple isolation strategies were applied to water and soil samples that were previously shown to be B. multivorans PCR positive. These included direct plating and liquid enrichment procedures and the use of selective media, acclimatizing recovery and co-cultivation with CF sputum. MALDI-TOF mass spectrometry and sequence analysis of 16S rRNA and housekeeping genes were used to identify all isolates. None of the approaches yielded B. multivorans isolates. Other Burkholderia species, several Gram-negative non-fermenting bacteria (including Cupriavidus, Inquilinus, Pandoraea, Pseudomonas and Stenotrophomonas) and rapidly growing mycobacteria (including Mycobacterium chelonae) were all isolated from water and soil samples. The use of Bcc isolation media yielded a surprisingly wide array of rare but often clinically relevant CF pathogens, confirming that soil and water are reservoirs of these infectious agents. Copyright © 2016 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

  1. Genetic diversity of symbiotic Paraburkholderia species isolated from nodules of Mimosa pudica (L.) and Phaseolus vulgaris (L.) grown in soils of the Brazilian Atlantic Forest (Mata Atlântica).

    Science.gov (United States)

    Dall'Agnol, Rebeca Fuzinatto; Bournaud, Caroline; de Faria, Sérgio Miana; Béna, Gilles; Moulin, Lionel; Hungria, Mariangela

    2017-04-01

    Some species of the genus Paraburkholderia that are able to nodulate and fix nitrogen in symbiosis with legumes are called β-rhizobia and represent a group of ecological and biotechnological importance. We used Mimosa pudica and Phaseolus vulgaris to trap 427 rhizobial isolates from rhizospheric soil of Mimoseae trees in the Brazilian Atlantic Forest. Eighty-four representative strains were selected according to the 16S rRNA haplotypes and taxonomically characterized using a concatenated 16S rRNA-recA phylogeny. Most strains were assembled in the genus Paraburkholderia, including Paraburkholderia sabiae and Pa. nodosa. Mesorhizobium (α-rhizobia) and Cupriavidus (β-rhizobia) were also isolated, but in smaller proportions. Multilocus sequence analysis and BOX-PCR analyses indicated that six clusters of Paraburkholderia represent potential new species. In the phylogenetic analysis of the nodC gene, the majority of the strains were positioned in the same groups as in the 16S rRNA-recA tree, indicative of stability and vertical inheritance, but we also identified horizontal transfer of nodC in Pa. sabiae. All α- and β-rhizobial species were trapped by both legumes, although preferences of the host plants for specific rhizobial species have been observed. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Phylogenetic Analysis and Antimicrobial Profiles of Cultured Emerging Opportunistic Pathogens (Phyla Actinobacteria and Proteobacteria) Identified in Hot Springs.

    Science.gov (United States)

    Jardine, Jocelyn Leonie; Abia, Akebe Luther King; Mavumengwana, Vuyo; Ubomba-Jaswa, Eunice

    2017-09-15

    Hot spring water may harbour emerging waterborne opportunistic pathogens that can cause infections in humans. We have investigated the diversity and antimicrobial resistance of culturable emerging and opportunistic bacterial pathogens, in water and sediment of hot springs located in Limpopo, South Africa. Aerobic bacteria were cultured and identified using 16S ribosomal DNA (rDNA) gene sequencing. The presence of Legionella spp. was investigated using real-time polymerase chain reaction. Isolates were tested for resistance to ten antibiotics representing six different classes: β-lactam (carbenicillin), aminoglycosides (gentamycin, kanamycin, streptomycin), tetracycline, amphenicols (chloramphenicol, ceftriaxone), sulphonamides (co-trimoxazole) and quinolones (nalidixic acid, norfloxacin). Gram-positive Kocuria sp. and Arthrobacter sp. and gram-negative Cupriavidus sp., Ralstonia sp., Cronobacter sp., Tepidimonas sp., Hafnia sp. and Sphingomonas sp. were isolated, all recognised as emerging food-borne pathogens. Legionella spp. was not detected throughout the study. Isolates of Kocuria , Arthrobacter and Hafnia and an unknown species of the class Gammaproteobacteria were resistant to two antibiotics in different combinations of carbenicillin, ceftriaxone, nalidixic acid and chloramphenicol. Cronobacter sp. was sensitive to all ten antibiotics. This study suggests that hot springs are potential reservoirs for emerging opportunistic pathogens, including multiple antibiotic resistant strains, and highlights the presence of unknown populations of emerging and potential waterborne opportunistic pathogens in the environment.

  3. Electrode Cultivation and Interfacial Electron Transport in Subsurface Microorganisms

    Science.gov (United States)

    Karbelkar, A. A.; Jangir, Y.; Reese, B. K.; Wanger, G.; Anderson, C.; El-Naggar, M.; Amend, J.

    2016-12-01

    Continental subsurface environments can present significant energetic challenges to the resident microorganisms. While these environments are geologically diverse, potentially allowing energy harvesting by microorganisms that catalyze redox reactions, many of the abundant electron donors and acceptors are insoluble and therefore not directly bioavailable. Microbes can use extracellular electron transfer (EET) as a metabolic strategy to interact with redox active surfaces. This process can be mimicked on electrode surfaces and hence can lead to enrichment and quantification of subsurface microorganisms A primary bioelectrochemical enrichment with different oxidizing and reducing potentials set up in a single bioreactor was applied in situ to subsurface microorganisms residing in iron oxide rich deposits in the Sanford Underground Research Facility. Secondary enrichment revealed a plethora of classified and unclassified subsurface microbiota on both oxidizing and reducing potentials. From this enrichment, we have isolated a Gram-positive Bacillus along with Gram-negative Cupriavidus and Anaerospora strains (as electrode reducers) and Comamonas (as an electrode oxidizer). The Bacillus and Comamonas isolates were subjected to a detailed electrochemical characterization in half-reactors at anodic and cathodic potentials, respectively. An increase in cathodic current upon inoculation and cyclic voltammetry measurements confirm the hypothesis that Comamonas is capable of electron uptake from electrodes. In addition, measurements of Bacillus on anodes hint towards novel mechanisms that allow EET from Gram-positive bacteria. This study suggests that electrochemical approaches are well positioned to dissect such extracellular interactions that may be prevalent in the subsurface, while using physical electrodes to emulate the microhabitats, redox and geochemical gradients, and the spatially dependent interspecies interactions encountered in the subsurface. Electrochemical

  4. New transposon tools tailored for metabolic engineering of Gram-negative microbial cell factories

    Directory of Open Access Journals (Sweden)

    Esteban eMartínez-García

    2014-10-01

    Full Text Available Re-programming microorganisms to modify their existing functions and/or to bestow bacteria with entirely new-to-Nature tasks have largely relied so far on specialized molecular biology tools. Such endeavors are not only relevant in the burgeoning metabolic engineering arena, but also instrumental to explore the functioning of complex regulatory networks from a fundamental point of view. À la carte modification of bacterial genomes thus calls for novel tools to make genetic manipulations easier. We propose the use of a series of new broad-host-range mini-Tn5 vectors, termed pBAMDs, for the delivery of gene(s into the chromosome of Gram-negative bacteria and for generating saturated mutagenesis libraries in gene function studies. These delivery vectors endow the user with the possibility of easy cloning and subsequent insertion of functional cargoes with three different antibiotic resistance markers (kanamycin, streptomycin, and gentamicin. After validating the pBAMD vectors in the environmental bacterium Pseudomonas putida KT2440, their use was also illustrated by inserting the entire poly(3-hydroxybutyrate (PHB synthesis pathway from Cupriavidus necator in the chromosome of a phosphotransacetylase mutant of Escherichia coli. PHB is a completely biodegradable polyester with a number of industrial applications that make it attractive as a potential replacement of oil-based plastics. The non-selective nature of chromosomal insertions of the biosynthetic genes was evidenced by a large landscape of PHB synthesis levels in independent clones. One clone was selected and further characterized as a microbial cell factory for PHB accumulation, and it achieved polymer accumulation levels comparable to those of a plasmid-bearing recombinant. Taken together, our results demonstrate that the new mini-Tn5 vectors can be used to confer interesting phenotypes in Gram-negative bacteria that would be very difficult to engineer through direct manipulation of the

  5. Community differentiation of the cutaneous microbiota in psoriasis.

    Science.gov (United States)

    Alekseyenko, Alexander V; Perez-Perez, Guillermo I; De Souza, Aieska; Strober, Bruce; Gao, Zhan; Bihan, Monika; Li, Kelvin; Methé, Barbara A; Blaser, Martin J

    2013-12-23

    Psoriasis is a common chronic inflammatory disease of the skin. We sought to characterize and compare the cutaneous microbiota of psoriatic lesions (lesion group), unaffected contralateral skin from psoriatic patients (unaffected group), and similar skin loci in matched healthy controls (control group) in order to discern patterns that govern skin colonization and their relationship to clinical diagnosis. Using high-throughput 16S rRNA gene sequencing, we assayed the cutaneous bacterial communities of 51 matched triplets and characterized these samples using community data analysis techniques. Intragroup Unifrac β diversity revealed increasing diversity from control to unaffected to lesion specimens. Likewise, principal coordinates analysis (PCoA) revealed separation of the lesion samples from unaffected and control along the first axis, suggesting that psoriasis is a major contributor to the observed diversity. The taxonomic richness and evenness decreased in both lesion and unaffected communities compared to control. These differences are explained by the combined increased abundance of the four major skin-associated genera (Corynebacterium, Propionibacterium, Staphylococcus, and Streptococcus), which present a potentially useful predictor for clinical skin type. Psoriasis samples also showed significant univariate decreases in relative abundances and strong classification performance of Cupriavidus, Flavisolibacter, Methylobacterium, and Schlegelella genera versus controls. The cutaneous microbiota separated into two distinct clusters, which we call cutaneotypes: (1) Proteobacteria-associated microbiota, and (2) Firmicutes-associated and Actinobacteria-associated microbiota. Cutaneotype 2 is enriched in lesion specimens compared to control (odds ratio 3.52 (95% CI 1.44 to 8.98), P microbial community structure in psoriasis patients are potentially of pathophysiologic and diagnostic significance.

  6. Simultaneous biodegradation of three mononitrophenol isomers by a tailor-made microbial consortium immobilized in sequential batch reactors.

    Science.gov (United States)

    Fu, H; Zhang, J-J; Xu, Y; Chao, H-J; Zhou, N-Y

    2017-03-01

    The ortho-nitrophenol (ONP)-utilizing Alcaligenes sp. strain NyZ215, meta-nitrophenol (MNP)-utilizing Cupriavidus necator JMP134 and para-nitrophenol (PNP)-utilizing Pseudomonas sp. strain WBC-3 were assembled as a consortium to degrade three nitrophenol isomers in sequential batch reactors. Pilot test was conducted in flasks to demonstrate that a mixture of three mononitrophenols at 0·5 mol l -1 each could be mineralized by this microbial consortium within 84 h. Interestingly, neither ONP nor MNP was degraded until PNP was almost consumed by strain WBC-3. By immobilizing this consortium into polyurethane cubes, all three mononitrophenols were continuously degraded in lab-scale sequential reactors for six batch cycles over 18 days. Total concentrations of ONP, MMP and PNP that were degraded were 2·8, 1·5 and 2·3 mol l -1 during this time course respectively. Quantitative real-time PCR analysis showed that each member in the microbial consortium was relatively stable during the entire degradation process. This study provides a novel approach to treat polluted water, particularly with a mixture of co-existing isomers. Nitroaromatic compounds are readily spread in the environment and pose great potential toxicity concerns. Here, we report the simultaneous degradation of three isomers of mononitrophenol in a single system by employing a consortium of three bacteria, both in flasks and lab-scale sequential batch reactors. The results demonstrate that simultaneous biodegradation of three mononitrophenol isomers can be achieved by a tailor-made microbial consortium immobilized in sequential batch reactors, providing a pilot study for a novel approach for the bioremediation of mixed pollutants, especially isomers present in wastewater. © 2016 The Society for Applied Microbiology.

  7. A fed-batch strategy to produce high poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxybutyrate) terpolymer yield with enhanced mechanical properties in bioreactor.

    Science.gov (United States)

    Aziz, Nursolehah Abd; Huong, Kai-Hee; Sipaut, Coswald Stephen; Amirul, A A

    2017-11-01

    This study reports an efficient fed-batch strategy to improve poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxybutyrate) [P(3HB-co-3HV-co-4HB)] terpolymer production by Cupriavidus sp. USMAA2-4 with enhanced mechanical properties in bioreactor. The cultivations have been performed by combining oleic acid with γ-butyrolactone at different concentration ratios with 1-pentanol at a fixed concentration. The batch and fed-batch fermentations have resulted in P(3HB-co-3HV-co-4HB) with compositions of 9-35 mol% 3HV and 4-24 mol% 4HB monomers. The DO-stat fed-batch fermentation strategies have significantly improved the production with a maximum 4.4-fold increment of cell dry weight (CDW). Besides, appropriate feeding of the substrates has resulted in an increment of terpolymer productivity from 0.086-0.347 g/L/h, with a significantly shortened cultivation time. The bacterial growth and terpolymer formation have been found to be affected by the concentration of carbon sources supplied. Characterization of P(3HB-co-3HV-co-4HB) has demonstrated that incorporation of 3HV and 4HB monomer has significantly improved the physical and thermodynamic properties of the polymers, by reducing the polymer's crystallinity. The tensile strength, Young's modulus of the terpolymer has been discovered to increase with the increase of M w . The fed-batch fermentation strategies employed in this study have resulted in terpolymers with a range of flexible materials having improved tensile strength and Young's modulus as compared to the terpolymer produced from batch fermentation. Possession of lower melting temperature indicates an enhanced thermal stability which broadens the polymer processing window.

  8. Pyrosequencing reveals the effect of mobilizing agents and lignocellulosic substrate amendment on microbial community composition in a real industrial PAH-polluted soil

    Energy Technology Data Exchange (ETDEWEB)

    Lladó, S., E-mail: llado@biomed.cas.cz [Department of Microbiology, University of Barcelona, Diagonal 645, E-08028 Barcelona (Spain); Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídenská 1083, 142 20 Prague 4 (Czech Republic); Covino, S., E-mail: covino@biomed.cas.cz [Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídenská 1083, 142 20 Prague 4 (Czech Republic); Solanas, A.M., E-mail: asolanas@ub.edu [Department of Microbiology, University of Barcelona, Diagonal 645, E-08028 Barcelona (Spain); Petruccioli, M., E-mail: petrucci@unitus.it [Department for Innovation in Biological, Agro-Food and Forest Systems [DIBAF], University of Tuscia, Via S. Camillo de Lellis snc, 01100 Viterbo (Italy); D’annibale, A., E-mail: dannib@unitus.it [Department for Innovation in Biological, Agro-Food and Forest Systems [DIBAF], University of Tuscia, Via S. Camillo de Lellis snc, 01100 Viterbo (Italy); Viñas, M., E-mail: marc.vinas@irta.cat [GIRO Joint Research Unit IRTA-UPC, Institute of Research and Technology Food and Agriculture [IRTA], Torre Marimon, E-08140 Caldes de Montbui (Spain)

    2015-02-11

    Highlights: • Soil microbial community assessment through classical (MPN) and molecular tools (DGGE and pyrosequencing) is provided. • A failure of exogenous white rot fungi to colonize the polluted soil is shown by DGGE and pyrosequencing. • Surfactant Brij 30 hampers 4-ring PAHs degradation due to toxicity over Actinobacteria and Bacteroidetes populations. • A high prevalence of Fusarium and Scedosporium populations is revealed during soil bioremediation. • Cupriavidus, Mycobacterium and Chithinophagaceae are potential HMW–PAH degraders in the soil. - Abstract: Bacterial and fungal biodiversity throughout different biostimulation and bioaugmentation treatments applied to an industrial creosote-polluted soil were analyzed by means of polyphasic approach in order to gain insight into the microbial community structure and dynamics. Pyrosequencing data obtained from initial creosote polluted soil (after a biopiling step) revealed that Alpha and Gammaproteobacteria were the most abundant bacterial groups, whereas Fusarium and Scedosporium were the main fungal genera in the contaminated soil. At the end of 60-days laboratory scale bioremediation assays, pyrosequencing and DGGE data showed that (i) major bacterial community shifts were caused by the type of mobilizing agent added to the soil and, to a lesser extent, by the addition of lignocellulosic substrate; and (ii) the presence of the non-ionic surfactant (Brij 30) hampered the proliferation of Actinobacteria (Mycobacteriaceae) and Bacteroidetes (Chitinophagaceae) and, in the absence of lignocellulosic substrate, also impeded polycyclic aromatic hydrocarbons (PAHs) degradation. The results show the importance of implementing bioremediation experiments combined with microbiome assessment to gain insight on the effect of crucial parameters (e.g. use of additives) over the potential functions of complex microbial communities harbored in polluted soils, essential for bioremediation success.

  9. Identification of tertiary butyl alcohol (TBA)-utilizing organisms in BioGAC reactors using 13C-DNA stable isotope probing.

    Science.gov (United States)

    Aslett, Denise; Haas, Joseph; Hyman, Michael

    2011-09-01

    Biodegradation of the gasoline oxygenates methyl tertiary-butyl ether (MTBE) and ethyl tertiary-butyl ether (ETBE) can cause tertiary butyl alcohol (TBA) to accumulate in gasoline-impacted environments. One remediation option for TBA-contaminated groundwater involves oxygenated granulated activated carbon (GAC) reactors that have been self-inoculated by indigenous TBA-degrading microorganisms in ground water extracted from contaminated aquifers. Identification of these organisms is important for understanding the range of TBA-metabolizing organisms in nature and for determining whether self-inoculation of similar reactors is likely to occur at other sites. In this study (13)C-DNA-stable isotope probing (SIP) was used to identify TBA-utilizing organisms in samples of self-inoculated BioGAC reactors operated at sites in New York and California. Based on 16S rRNA nucleotide sequences, all TBA-utilizing organisms identified were members of the Burkholderiales order of the β-proteobacteria. Organisms similar to Cupriavidus and Methylibium were observed in both reactor samples while organisms similar to Polaromonas and Rhodoferax were unique to the reactor sample from New York. Organisms similar to Hydrogenophaga and Paucibacter strains were only detected in the reactor sample from California. We also analyzed our samples for the presence of several genes previously implicated in TBA oxidation by pure cultures of bacteria. Genes Mpe_B0532, B0541, B0555, and B0561 were all detected in (13)C-metagenomic DNA from both reactors and deduced amino acid sequences suggested these genes all encode highly conserved enzymes. One gene (Mpe_B0555) encodes a putative phthalate dioxygenase-like enzyme that may be particularly appropriate for determining the potential for TBA oxidation in contaminated environmental samples.

  10. Biochemical characterization of ethanol-dependent reduction of furfural by alcohol dehydrogenases.

    Science.gov (United States)

    Li, Qunrui; Metthew Lam, L K; Xun, Luying

    2011-11-01

    Lignocellulosic biomass is usually converted to hydrolysates, which consist of sugars and sugar derivatives, such as furfural. Before yeast ferments sugars to ethanol, it reduces toxic furfural to non-inhibitory furfuryl alcohol in a prolonged lag phase. Bioreduction of furfural may shorten the lag phase. Cupriavidus necator JMP134 rapidly reduces furfural with a Zn-dependent alcohol dehydrogenase (FurX) at the expense of ethanol (Li et al. 2011). The mechanism of the ethanol-dependent reduction of furfural by FurX and three homologous alcohol dehydrogenases was investigated. The reduction consisted of two individual reactions: ethanol-dependent reduction of NAD(+) to NADH and then NADH-dependent reduction of furfural to furfuryl alcohol. The kinetic parameters of the coupled reaction and the individual reactions were determined for the four enzymes. The data indicated that limited NADH was released in the coupled reaction. The enzymes had high affinities for NADH (e.g., K ( d ) of 0.043 μM for the FurX-NADH complex) and relatively low affinities for NAD(+) (e.g., K ( d ) of 87 μM for FurX-NAD(+)). The kinetic data suggest that the four enzymes are efficient "furfural reductases" with either ethanol or NADH as the reducing power. The standard free energy change (ΔG°') for ethanol-dependent reduction of furfural was determined to be -1.1 kJ mol(-1). The physiological benefit for ethanol-dependent reduction of furfural is likely to replace toxic and recalcitrant furfural with less toxic and more biodegradable acetaldehyde.

  11. Whole genome amplification approach reveals novel polyhydroxyalkanoate synthases (PhaCs) from Japan Trench and Nankai Trough seawater.

    Science.gov (United States)

    Foong, Choon Pin; Lau, Nyok-Sean; Deguchi, Shigeru; Toyofuku, Takashi; Taylor, Todd D; Sudesh, Kumar; Matsui, Minami

    2014-12-24

    Special features of the Japanese ocean include its ranges of latitude and depth. This study is the first to examine the diversity of Class I and II PHA synthases (PhaC) in DNA samples from pelagic seawater taken from the Japan Trench and Nankai Trough from a range of depths from 24 m to 5373 m. PhaC is the key enzyme in microorganisms that determines the types of monomer units that are polymerized into polyhydroxyalkanoate (PHA) and thus affects the physicochemical properties of this thermoplastic polymer. Complete putative PhaC sequences were determined via genome walking, and the activities of newly discovered PhaCs were evaluated in a heterologous host. A total of 76 putative phaC PCR fragments were amplified from the whole genome amplified seawater DNA. Of these 55 clones contained conserved PhaC domains and were classified into 20 genetic groups depending on their sequence similarity. Eleven genetic groups have undisclosed PhaC activity based on their distinct phylogenetic lineages from known PHA producers. Three complete DNA coding sequences were determined by IAN-PCR, and one PhaC was able to produce poly(3-hydroxybutyrate) in recombinant Cupriavidus necator PHB-4 (PHB-negative mutant). A new functional PhaC that has close identity to Marinobacter sp. was discovered in this study. Phylogenetic classification for all the phaC genes isolated from uncultured bacteria has revealed that seawater and other environmental resources harbor a great diversity of PhaCs with activities that have not yet been investigated. Functional evaluation of these in silico-based PhaCs via genome walking has provided new insights into the polymerizing ability of these enzymes.

  12. New Transposon Tools Tailored for Metabolic Engineering of Gram-Negative Microbial Cell Factories

    International Nuclear Information System (INIS)

    Martínez-García, Esteban; Aparicio, Tomás; Lorenzo, Víctor de; Nikel, Pablo I.

    2014-01-01

    Re-programming microorganisms to modify their existing functions and/or to bestow bacteria with entirely new-to-Nature tasks have largely relied so far on specialized molecular biology tools. Such endeavors are not only relevant in the burgeoning metabolic engineering arena but also instrumental to explore the functioning of complex regulatory networks from a fundamental point of view. À la carte modification of bacterial genomes thus calls for novel tools to make genetic manipulations easier. We propose the use of a series of new broad-host-range mini-Tn5-vectors, termed pBAMDs, for the delivery of gene(s) into the chromosome of Gram-negative bacteria and for generating saturated mutagenesis libraries in gene function studies. These delivery vectors endow the user with the possibility of easy cloning and subsequent insertion of functional cargoes with three different antibiotic-resistance markers (kanamycin, streptomycin, and gentamicin). After validating the pBAMD vectors in the environmental bacterium Pseudomonas putida KT2440, their use was also illustrated by inserting the entire poly(3-hydroxybutyrate) (PHB) synthesis pathway from Cupriavidus necator in the chromosome of a phosphotransacetylase mutant of Escherichia coli. PHB is a completely biodegradable polyester with a number of industrial applications that make it attractive as a potential replacement of oil-based plastics. The non-selective nature of chromosomal insertions of the biosynthetic genes was evidenced by a large landscape of PHB synthesis levels in independent clones. One clone was selected and further characterized as a microbial cell factory for PHB accumulation, and it achieved polymer accumulation levels comparable to those of a plasmid-bearing recombinant. Taken together, our results demonstrate that the new mini-Tn5-vectors can be used to confer interesting phenotypes in Gram-negative bacteria that would be very difficult to engineer through direct manipulation of the structural genes.

  13. Isolation of phyllosilicate-iron redox cycling microorganisms from an illite-smectite rich hydromorphic soil.

    Science.gov (United States)

    Shelobolina, Evgenya; Konishi, Hiromi; Xu, Huifang; Benzine, Jason; Xiong, Mai Yia; Wu, Tao; Blöthe, Marco; Roden, Eric

    2012-01-01

    The biogeochemistry of phyllosilicate-Fe redox cycling was studied in a Phalaris arundinacea (reed canary grass) dominated redoximorphic soil from Shovelers Sink, a small glacial depression near Madison, WI. The clay size fraction of Shovelers Sink soil accounts for 16% of the dry weight of the soil, yet contributes 74% of total Fe. The dominant mineral in the clay size fraction is mixed layer illite-smectite, and in contrast to many other soils and sediments, Fe(III) oxides are present in low abundance. We examined the Fe biogeochemistry of Shovelers Sink soils, estimated the abundance of Fe redox cycling microorganisms, and isolated in pure culture representative phyllosilicate-Fe oxidizing and reducing organisms. The abundance of phyllosilicate-Fe reducing and oxidizing organisms was low compared to culturable aerobic heterotrophs. Both direct isolation and dilution-to-extinction approaches using structural Fe(II) in Bancroft biotite as a Fe(II) source, and O(2) as the electron acceptor, resulted in recovery of common rhizosphere organisms including Bradyrhizobium spp. and strains of Cupriavidus necator and Ralstonia solanacearum. In addition to oxidizing biotite and soluble Fe(II) with O(2), each of these isolates was able to oxidize Fe(II) in reduced NAu-2 smectite with [Formula: see text] as the electron acceptor. Oxidized NAu-2 smectite or amorphous Fe(III) oxide served as electron acceptors for enrichment and isolation of Fe(III)-reducing microorganisms, resulting in recovery of a strain related to Geobacter toluenoxydans. The ability of the recovered microorganisms to cycle phyllosilicate-Fe was verified in an experiment with native Shovelers Sink clay. This study confirms that Fe in the native Shovelers Sink clay is readily available for microbial redox transformation and can be cycled by the Fe(III)-reducing and Fe(II)-oxidizing microorganisms recovered from the soil.

  14. Isolation of Phyllosilicate–Iron Redox Cycling Microorganisms from an Illite–Smectite Rich Hydromorphic Soil

    Science.gov (United States)

    Shelobolina, Evgenya; Konishi, Hiromi; Xu, Huifang; Benzine, Jason; Xiong, Mai Yia; Wu, Tao; Blöthe, Marco; Roden, Eric

    2012-01-01

    The biogeochemistry of phyllosilicate–Fe redox cycling was studied in a Phalaris arundinacea (reed canary grass) dominated redoximorphic soil from Shovelers Sink, a small glacial depression near Madison, WI. The clay size fraction of Shovelers Sink soil accounts for 16% of the dry weight of the soil, yet contributes 74% of total Fe. The dominant mineral in the clay size fraction is mixed layer illite–smectite, and in contrast to many other soils and sediments, Fe(III) oxides are present in low abundance. We examined the Fe biogeochemistry of Shovelers Sink soils, estimated the abundance of Fe redox cycling microorganisms, and isolated in pure culture representative phyllosilicate–Fe oxidizing and reducing organisms. The abundance of phyllosilicate–Fe reducing and oxidizing organisms was low compared to culturable aerobic heterotrophs. Both direct isolation and dilution-to-extinction approaches using structural Fe(II) in Bancroft biotite as a Fe(II) source, and O2 as the electron acceptor, resulted in recovery of common rhizosphere organisms including Bradyrhizobium spp. and strains of Cupriavidus necator and Ralstonia solanacearum. In addition to oxidizing biotite and soluble Fe(II) with O2, each of these isolates was able to oxidize Fe(II) in reduced NAu-2 smectite with NO3- as the electron acceptor. Oxidized NAu-2 smectite or amorphous Fe(III) oxide served as electron acceptors for enrichment and isolation of Fe(III)-reducing microorganisms, resulting in recovery of a strain related to Geobacter toluenoxydans. The ability of the recovered microorganisms to cycle phyllosilicate–Fe was verified in an experiment with native Shovelers Sink clay. This study confirms that Fe in the native Shovelers Sink clay is readily available for microbial redox transformation and can be cycled by the Fe(III)-reducing and Fe(II)-oxidizing microorganisms recovered from the soil. PMID:22493596

  15. Structural characterization of the bacterial proteasome homolog BPH reveals a tetradecameric double-ring complex with unique inner cavity properties.

    Science.gov (United States)

    Fuchs, Adrian C D; Maldoner, Lorena; Hipp, Katharina; Hartmann, Marcus D; Martin, Jörg

    2018-01-19

    Eukaryotic and archaeal proteasomes are paradigms for self-compartmentalizing proteases. To a large extent, their function requires interplay with hexameric ATPases associated with diverse cellular activities (AAA+) that act as substrate unfoldases. Bacteria have various types of self-compartmentalizing proteases; in addition to the proteasome itself, these include the proteasome homolog HslV, which functions together with the AAA+ HslU; the ClpP protease with its partner AAA+ ClpX; and Anbu, a recently characterized ancestral proteasome variant. Previous bioinformatic analysis has revealed a novel bacterial member of the proteasome family Betaproteobacteria proteasome homolog (BPH). Using cluster analysis, we here affirmed that BPH evolutionarily descends from HslV. Crystal structures of the Thiobacillus denitrificans and Cupriavidus metallidurans BPHs disclosed a homo-oligomeric double-ring architecture in which the active sites face the interior of the cylinder. Using small-angle X-ray scattering (SAXS) and electron microscopy averaging, we found that BPH forms tetradecamers in solution, unlike the dodecamers seen in HslV. Although the highly acidic inner surface of BPH was in striking contrast to the cavity characteristics of the proteasome and HslV, a classical proteasomal reaction mechanism could be inferred from the covalent binding of the proteasome-specific inhibitor epoxomicin to BPH. A ligand-bound structure implied that the elongated BPH inner pore loop may be involved in substrate recognition. The apparent lack of a partner unfoldase and other unique features, such as Ser replacing Thr as the catalytic residue in certain BPH subfamilies, suggest a proteolytic function for BPH distinct from those of known bacterial self-compartmentalizing proteases. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Linkage of the Nit1C gene cluster to bacterial cyanide assimilation as a nitrogen source.

    Science.gov (United States)

    Jones, Lauren B; Ghosh, Pallab; Lee, Jung-Hyun; Chou, Chia-Ni; Kunz, Daniel A

    2018-05-21

    A genetic linkage between a conserved gene cluster (Nit1C) and the ability of bacteria to utilize cyanide as the sole nitrogen source was demonstrated for nine different bacterial species. These included three strains whose cyanide nutritional ability has formerly been documented (Pseudomonas fluorescens Pf11764, Pseudomonas putida BCN3 and Klebsiella pneumoniae BCN33), and six not previously known to have this ability [Burkholderia (Paraburkholderia) xenovorans LB400, Paraburkholderia phymatum STM815, Paraburkholderia phytofirmans PsJN, Cupriavidus (Ralstonia) eutropha H16, Gluconoacetobacter diazotrophicus PA1 5 and Methylobacterium extorquens AM1]. For all bacteria, growth on or exposure to cyanide led to the induction of the canonical nitrilase (NitC) linked to the gene cluster, and in the case of Pf11764 in particular, transcript levels of cluster genes (nitBCDEFGH) were raised, and a nitC knock-out mutant failed to grow. Further studies demonstrated that the highly conserved nitB gene product was also significantly elevated. Collectively, these findings provide strong evidence for a genetic linkage between Nit1C and bacterial growth on cyanide, supporting use of the term cyanotrophy in describing what may represent a new nutritional paradigm in microbiology. A broader search of Nit1C genes in presently available genomes revealed its presence in 270 different bacteria, all contained within the domain Bacteria, including Gram-positive Firmicutes and Actinobacteria, and Gram-negative Proteobacteria and Cyanobacteria. Absence of the cluster in the Archaea is congruent with events that may have led to the inception of Nit1C occurring coincidentally with the first appearance of cyanogenic species on Earth, dating back 400-500 million years.

  17. Proof that Burkholderia Strains Form Effective Symbioses with Legumes: a Study of Novel Mimosa-Nodulating Strains from South America

    Science.gov (United States)

    Chen, Wen-Ming; de Faria, Sergio M.; Straliotto, Rosângela; Pitard, Rosa M.; Simões-Araùjo, Jean L.; Chou, Jui-Hsing; Chou, Yi-Ju; Barrios, Edmundo; Prescott, Alan R.; Elliott, Geoffrey N.; Sprent, Janet I.; Young, J. Peter W.; James, Euan K.

    2005-01-01

    Twenty Mimosa-nodulating bacterial strains from Brazil and Venezuela, together with eight reference Mimosa-nodulating rhizobial strains and two other β-rhizobial strains, were examined by amplified rRNA gene restriction analysis. They fell into 16 patterns and formed a single cluster together with the known β-rhizobia, Burkholderia caribensis, Burkholderia phymatum, and Burkholderia tuberum. The 16S rRNA gene sequences of 15 of the 20 strains were determined, and all were shown to belong to the genus Burkholderia; four distinct clusters could be discerned, with strains isolated from the same host species usually clustering very closely. Five of the strains (MAP3-5, Br3407, Br3454, Br3461, and Br3469) were selected for further studies of the symbiosis-related genes nodA, the NodD-dependent regulatory consensus sequences (nod box), and nifH. The nodA and nifH sequences were very close to each other and to those of B. phymatum STM815, B. caribensis TJ182, and Cupriavidus taiwanensis LMG19424 but were relatively distant from those of B. tuberum STM678. In addition to nodulating their original hosts, all five strains could also nodulate other Mimosa spp., and all produced nodules on Mimosa pudica that had nitrogenase (acetylene reduction) activities and structures typical of effective N2-fixing symbioses. Finally, both wild-type and green fluorescent protein-expressing transconjugant strains of Br3461 and MAP3-5 produced N2-fixing nodules on their original hosts, Mimosa bimucronata (Br3461) and Mimosa pigra (MAP3-5), and hence this confirms strongly that Burkholderia strains can form effective symbioses with legumes. PMID:16269788

  18. New Transposon Tools Tailored for Metabolic Engineering of Gram-Negative Microbial Cell Factories

    Energy Technology Data Exchange (ETDEWEB)

    Martínez-García, Esteban; Aparicio, Tomás; Lorenzo, Víctor de; Nikel, Pablo I., E-mail: pablo.nikel@cnb.csic.es [Systems and Synthetic Biology Program, Centro Nacional de Biotecnología (CNB-CSIC), Madrid (Spain)

    2014-10-28

    Re-programming microorganisms to modify their existing functions and/or to bestow bacteria with entirely new-to-Nature tasks have largely relied so far on specialized molecular biology tools. Such endeavors are not only relevant in the burgeoning metabolic engineering arena but also instrumental to explore the functioning of complex regulatory networks from a fundamental point of view. À la carte modification of bacterial genomes thus calls for novel tools to make genetic manipulations easier. We propose the use of a series of new broad-host-range mini-Tn5-vectors, termed pBAMDs, for the delivery of gene(s) into the chromosome of Gram-negative bacteria and for generating saturated mutagenesis libraries in gene function studies. These delivery vectors endow the user with the possibility of easy cloning and subsequent insertion of functional cargoes with three different antibiotic-resistance markers (kanamycin, streptomycin, and gentamicin). After validating the pBAMD vectors in the environmental bacterium Pseudomonas putida KT2440, their use was also illustrated by inserting the entire poly(3-hydroxybutyrate) (PHB) synthesis pathway from Cupriavidus necator in the chromosome of a phosphotransacetylase mutant of Escherichia coli. PHB is a completely biodegradable polyester with a number of industrial applications that make it attractive as a potential replacement of oil-based plastics. The non-selective nature of chromosomal insertions of the biosynthetic genes was evidenced by a large landscape of PHB synthesis levels in independent clones. One clone was selected and further characterized as a microbial cell factory for PHB accumulation, and it achieved polymer accumulation levels comparable to those of a plasmid-bearing recombinant. Taken together, our results demonstrate that the new mini-Tn5-vectors can be used to confer interesting phenotypes in Gram-negative bacteria that would be very difficult to engineer through direct manipulation of the structural genes.

  19. Symbiotic Burkholderia Species Show Diverse Arrangements of nif/fix and nod Genes and Lack Typical High-Affinity Cytochrome cbb3 Oxidase Genes.

    Science.gov (United States)

    De Meyer, Sofie E; Briscoe, Leah; Martínez-Hidalgo, Pilar; Agapakis, Christina M; de-Los Santos, Paulina Estrada; Seshadri, Rekha; Reeve, Wayne; Weinstock, George; O'Hara, Graham; Howieson, John G; Hirsch, Ann M

    2016-08-01

    Genome analysis of fourteen mimosoid and four papilionoid beta-rhizobia together with fourteen reference alpha-rhizobia for both nodulation (nod) and nitrogen-fixing (nif/fix) genes has shown phylogenetic congruence between 16S rRNA/MLSA (combined 16S rRNA gene sequencing and multilocus sequence analysis) and nif/fix genes, indicating a free-living diazotrophic ancestry of the beta-rhizobia. However, deeper genomic analysis revealed a complex symbiosis acquisition history in the beta-rhizobia that clearly separates the mimosoid and papilionoid nodulating groups. Mimosoid-nodulating beta-rhizobia have nod genes tightly clustered in the nodBCIJHASU operon, whereas papilionoid-nodulating Burkholderia have nodUSDABC and nodIJ genes, although their arrangement is not canonical because the nod genes are subdivided by the insertion of nif and other genes. Furthermore, the papilionoid Burkholderia spp. contain duplications of several nod and nif genes. The Burkholderia nifHDKEN and fixABC genes are very closely related to those found in free-living diazotrophs. In contrast, nifA is highly divergent between both groups, but the papilionoid species nifA is more similar to alpha-rhizobia nifA than to other groups. Surprisingly, for all Burkholderia, the fixNOQP and fixGHIS genes required for cbb3 cytochrome oxidase production and assembly are missing. In contrast, symbiotic Cupriavidus strains have fixNOQPGHIS genes, revealing a divergence in the evolution of two distinct electron transport chains required for nitrogen fixation within the beta-rhizobia.

  20. Efficacy of Various Chemical Disinfectants on Biofilms Formed in Spacecraft Potable Water System Component

    Science.gov (United States)

    Wong, Willy; Garcia, Veronica; Castro, Victoria; Ott, Mark; Duane

    2009-01-01

    As the provision of potable water is critical for successful habitation of the International Space Station (ISS), life support systems were installed in December 2008 to recycle both humidity from the atmosphere and urine to conserve available water in the vehicle. Pre-consumption testing from the dispensing needle at the Potable Water Dispenser (PWD) indicated that bacterial concentrations exceeded the current ISS specifications of 50 colony forming units (CFU) per ml. Subsequent investigations revealed that a corrugated stainless steel flex hose upstream of the dispensing needle in the PWD was filled with non-sterile water and left at room temperature for over one month before launch. To simulate biofilm formation that was suspected in the flight system, sterile flex hoses were seeded with a consortium of bacterial isolates previously recovered from other ISS water systems, which included Ralstonia pickettii, Burkholderia multivorans, Caulobacter vibrioides., and Cupriavidus pauculus. After 5 days of incubation, these hoses were challenged with various chemical disinfectants including hydrogen peroxide, colloidal silver, and buffered pH solutions to determine the ability of the disinfectants to decrease and maintain bacterial concentrations below ISS specifications. Disinfection efficacy over time was measured by collecting daily heterotrophic plate counts following exposure to the disinfectants. A single flush with either 6% hydrogen peroxide solution or a mixture of 3% hydrogen peroxide and 400 ppb colloidal silver effectively reduced the bacterial concentrations to less than 1 CFU/ml for a period of up to 2 months. Testing results indicated that hydrogen peroxide and mixtures of hydrogen peroxide and colloidal silver have tremendous potential as alternative disinfectants for ISS water systems.

  1. Biological Recovery of Platinum Complexes from Diluted Aqueous Streams by Axenic Cultures.

    Directory of Open Access Journals (Sweden)

    Synthia Maes

    Full Text Available The widespread use of platinum in high-tech and catalytic applications has led to the production of diverse Pt loaded wastewaters. Effective recovery strategies are needed for the treatment of low concentrated waste streams to prevent pollution and to stimulate recovery of this precious resource. The biological recovery of five common environmental Pt-complexes was studied under acidic conditions; the chloro-complexes PtCl42- and PtCl62-, the amine-complex Pt(NH34Cl2 and the pharmaceutical complexes cisplatin and carboplatin. Five bacterial species were screened on their platinum recovery potential; the Gram-negative species Shewanella oneidensis MR-1, Cupriavidus metallidurans CH34, Geobacter metallireducens, and Pseudomonas stutzeri, and the Gram-positive species Bacillus toyonensis. Overall, PtCl42- and PtCl62- were completely recovered by all bacterial species while only S. oneidensis and C. metallidurans were able to recover cisplatin quantitatively (99%, all in the presence of H2 as electron donor at pH 2. Carboplatin was only partly recovered (max. 25% at pH 7, whereas no recovery was observed in the case of the Pt-tetraamine complex. Transmission electron microscopy (TEM revealed the presence of both intra- and extracellular platinum particles. Flow cytometry based microbial viability assessment demonstrated the decrease in number of intact bacterial cells during platinum reduction and indicated C. metallidurans to be the most resistant species. This study showed the effective and complete biological recovery of three common Pt-complexes, and estimated the fate and transport of the Pt-complexes in wastewater treatment plants and the natural environment.

  2. Ralstonia eutropha's Poly(3-hydroxybutyrate)(PHB) polymerase PhaC1 and PHB depolymerase PhaZa1 are phosphorylated in vivo.

    Science.gov (United States)

    Jüngert, Janina R; Patterson, Cameron; Jendrossek, Dieter

    2018-04-20

    In this study, we screened PHB synthase PhaC1 and PHB depolymerase PhaZa1 of Ralstonia eutropha for the presence of phosphorylated residues during the PHB accumulation and PHB degradation phase. Thr373 of PHB synthase PhaC1 was phosphorylated in the stationary growth phase but was not modified in the exponential and PHB accumulation phases. Ser35 of PHB depolymerase PhaZa1 was identified in phosphorylated form both in the exponential and in the stationary growth phase. Additional phosphosites were identified for both proteins in sample-dependent forms. Site-directed mutagenesis of the codon for Thr373 and other phosphosites of PhaC1 revealed a strong negative impact on PHB synthase activity. Modification of Thr26 and Ser35 of PhaZa1 reduced the ability of R. eutropha to mobilize PHB in the stationary growth phase. Our results show that phosphorylation of PhaC1 and PhaZa1 can be important for modulation of the activities of PHB synthase and PHB depolymerase. Importance Polyhydroxybutyrate (PHB) and related polyhydroxyalkanoates (PHAs) are important intracellular carbon and energy storage compounds in many prokaryotes. The accumulation of PHB or PHAs increases the fitness of cells during periods of starvation and other stress conditions. The simultaneous presence of poly(3-hydroxybutyrate) (PHB) synthase (PhaC1) and PHB depolymerase (PhaZa1) on synthesized PHB granules in Ralstonia eutropha (alternative designation Cupriavidus necator ) has been previously shown in several laboratories. These findings imply that the activities of PHB synthase and PHB depolymerase should be regulated to avoid a futile cycle of simultaneous synthesis and degradation of PHB. Here, we addressed this question by identifying phosphorylation sites on PhaC1 and PhaZa1 and by site-directed mutagenesis of identified residues. Furthermore, we conducted in vitro and in vivo analysis of PHB synthase activity and PHB contents. Copyright © 2018 American Society for Microbiology.

  3. Size control and catalytic activity of bio-supported palladium nanoparticles.

    Science.gov (United States)

    Søbjerg, Lina Sveidal; Lindhardt, Anders T; Skrydstrup, Troels; Finster, Kai; Meyer, Rikke Louise

    2011-07-01

    The development of nanoparticles has greatly improved the catalytic properties of metals due to the higher surface to volume ratio of smaller particles. The production of nanoparticles is most commonly based on abiotic processes, but in the search for alternative protocols, bacterial cells have been identified as excellent scaffolds of nanoparticle nucleation, and bacteria have been successfully employed to recover and regenerate platinum group metals from industrial waste. We report on the formation of bio-supported palladium (Pd) nanoparticles on the surface of two bacterial species with distinctly different surfaces: the gram positive Staphylococcus sciuri and the gram negative Cupriavidus necator. We investigated how the type of bacterium and the amount of biomass affected the size and catalytic properties of the nanoparticles formed. By increasing the biomass:Pd ratio, we could produce bio-supported Pd nanoparticles smaller than 10nm in diameter, whereas lower biomass:Pd ratios resulted in particles ranging from few to hundreds of nm. The bio-supported Pd nanoparticle catalytic properties were investigated towards the Suzuki-Miyaura cross coupling reaction and hydrogenation reactions. Surprisingly, the smallest nanoparticles obtained at the highest biomass:Pd ratio showed no reactivity towards the test reactions. The lack of reactivity appears to be caused by thiol groups, which poison the catalyst by binding strongly to Pd. Different treatments intended to liberate particles from the biomass, such as burning or rinsing in acetone, did not re-establish their catalytic activity. Sulphur-free biomaterials should therefore be explored as more suitable scaffolds for Pd(0) nanoparticle formation. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Rhizobia symbiosis of seven leguminous species growing along Xindian riverbank of Northern Taiwan

    Directory of Open Access Journals (Sweden)

    Cheng-Tai Huang

    2018-01-01

    Full Text Available Legume-rhizobia symbioses of seven leguminous species growing along Xindian riverbank of Northern Taiwan were investigated in this study. These legumes form either determinate or indeterminate types of root nodules. The determinate nodules of Alysicarpus vaginalis, Desmodium. triflorum, D. heterophyllum, Sesbania cannabina and the indeterminate nodules of Mimosa pudica harbored bacteroids of morphological uniformity (length of 1-3 μm, while the indeterminate nodules of Crotalaria zanzibarica and Trifolium repens contained bacteroids of highly pleomorphism (size varying from 1 to 5 μm. The enclosed bacteria were isolated from respective nodules, and twenty slow-growing and nine fast-growing rhizobial isolates were recovered. The slow-growing isolates were classified to the genus Bradyrhizobium based on the 16S rRNA sequences, whereas the fast-growing rhizobia comprise four genera, Neorhizobium, Rhizobium, Cupriavidus and Paraburkholderia. Results of stable isotope analyses revealed that the seven leguminous species had similar and consistently negative δ15N values in leaves (mean of -1.2 ‰, whereas the values were positive (varying from 3.7 to 7.3 ‰ in the nodules. These values were significantly higher in the indeterminate nodules than those in the determinate ones. In addition, variations in the values of leaf δ13C (varying from -29 to -34‰ among the seven legumes were measured, indicating their photosynthetic water use efficiencies were different. This is the first field survey to report the rhizobial diversity and the nutrient relationships of sympatric legume in Taiwan.

  5. Production of (R)-3-hydroxybutyric acid by Arxula adeninivorans.

    Science.gov (United States)

    Biernacki, Mateusz; Riechen, Jan; Hähnel, Urs; Roick, Thomas; Baronian, Kim; Bode, Rüdiger; Kunze, Gotthard

    2017-12-01

    (R)-3-hydroxybutyric acid can be used in industrial and health applications. The synthesis pathway comprises two enzymes, β-ketothiolase and acetoacetyl-CoA reductase which convert cytoplasmic acetyl-CoA to (R)-3-hydroxybutyric acid [(R)-3-HB] which is released into the culture medium. In the present study we used the non-conventional yeast, Arxula adeninivorans, for the synthesis enantiopure (R)-3-HB. To establish optimal production, we investigated three different endogenous yeast thiolases (Akat1p, Akat2p, Akat4p) and three bacterial thiolases (atoBp, thlp, phaAp) in combination with an enantiospecific reductase (phaBp) from Cupriavidus necator H16 and endogenous yeast reductases (Atpk2p, Afox2p). We found that Arxula is able to release (R)-3-HB used an existing secretion system negating the need to engineer membrane transport. Overexpression of thl and phaB genes in organisms cultured in a shaking flask resulted in 4.84 g L -1 (R)-3-HB, at a rate of 0.023 g L -1  h -1 over 214 h. Fed-batch culturing with glucose as a carbon source did not improve the yield, but a similar level was reached with a shorter incubation period [3.78 g L -1 of (R)-3-HB at 89 h] and the rate of production was doubled to 0.043 g L -1  h -1 which is higher than any levels in yeast reported to date. The secreted (R)-3-HB was 99.9% pure. This is the first evidence of enantiopure (R)-3-HB synthesis using yeast as a production host and glucose as a carbon source.

  6. Characterization and bioremediation potential of phosphate solubilizing bacteria isolated from tunisian phosphogypsum

    International Nuclear Information System (INIS)

    Trifi, Houda

    2011-01-01

    Phosphorus bioavailability is often limited in agricultural soils. In this work, two bacteria were isolated from Tunisian phosphogypsum (PG). These ones have the capacity to dissolve inorganic phosphate (CaHPO 4 and Ca 3 (PO 4 ) 2 ). This capacity is determined by the clear halo formation around colonies in NBRIP agar medium. To confirm the solubilization phenotype, the concentration of solubilized phosphate by isolates cultivated in NBRIP broth containing PG was measured. These two bacteria noted BRM17 and BRM18 are identified as Pantoea sp. and Pseudomonas sp, respectively. The results show that BRM17 solubilizes about 2 times more phosphate in broth NBRIP medium after 48 hours of incubation than BRM18. Tunisian phosphogypsum contains 1100 ppm of strontium (Sr). Sr toxicity on bacteria was determined by concentration that gives half-maximal inhibition of bacteria (IC 50 ). Compared with Cupriavidus metallidurans (bacteria tolerant to most of heavy metals), BRM17 and BRM18 cultivated in broth medium containing increasing concentrations of Sr were found tolerant to Sr. The potential of bioremediation is tested by the rate evaluation of Sr adsorption by these bacteria. The results show the high ability of BRM18 to adsorb Sr. The resistance of isolates to ionizing radiation is also determined by the exposure of bacterial cultures to various doses of gamma radiation. BRM17 is considered radioresistant while BRM18 is radiosensitive. The effect on seed germination of wheat and pea inoculated with bacteria was tested. No positive effect was detected. This study is considered with the use of BRM17 and BRM18 in a bioremediation process and the improvement of phosphate uptake by plants cultivated in polluted environments.

  7. Study of the impact of environmental bacteria ob uranium speciation in order to engage bioremediation process

    International Nuclear Information System (INIS)

    Untereiner, G.

    2008-11-01

    Uranium is both a radiological and a chemical toxic. Its concentration in the environment is low except when human activities have caused pollution. Uranium is a heavy reactive element, and thus it is easily complexed with soil component like minerals or organic molecules. These different complexes can be more or less bioavailable for microorganisms and plants, and then get in the human food chain. The knowledge and the understanding of transfer mechanisms and also the fate of toxic elements in the biosphere are a key issue to estimate health and ecological hazards. The knowledge of the speciation is very important for bioremediation processes. Here, we focused on the microorganisms effects onto uranium speciation in environment. Bacteria can accumulate and/or transform uranium depending on the initial form of the element. Thus, its bioavailability could be changed. The species used in this work are Cupriavidus metallidurans CH34, which is an environmental bacteria with a high resistance to heavy metal, Deinococcus radiodurans R1, which is known for his radiological resistance, and Rhodopseudomonas palustris, which is a purple photo-trophic bacteria capable of degrading aromatic compounds. Two forms of uranium were used with these bacteria, a mineral one, uranyl carbonate, and an organic one, uranyl citrate. In a first step, the growth media were modified in order to stabilize uranium complexes thanks to a simulation program. Then, the capacity of the bacteria to accumulate or transform uranium was studied. We saw a difference between minimal inhibition concentrations of these two speciation which is due to a difference between phosphate bioavailability. No accumulation was observed with environmental pH but uranium precipitation was observed with acidic pH (pH 1). Uranium speciation seemed to be well controlled in the growth media and the precipitates were uranyl phosphate. (author)

  8. Pyrosequencing reveals the effect of mobilizing agents and lignocellulosic substrate amendment on microbial community composition in a real industrial PAH-polluted soil

    International Nuclear Information System (INIS)

    Lladó, S.; Covino, S.; Solanas, A.M.; Petruccioli, M.; D’annibale, A.; Viñas, M.

    2015-01-01

    Highlights: • Soil microbial community assessment through classical (MPN) and molecular tools (DGGE and pyrosequencing) is provided. • A failure of exogenous white rot fungi to colonize the polluted soil is shown by DGGE and pyrosequencing. • Surfactant Brij 30 hampers 4-ring PAHs degradation due to toxicity over Actinobacteria and Bacteroidetes populations. • A high prevalence of Fusarium and Scedosporium populations is revealed during soil bioremediation. • Cupriavidus, Mycobacterium and Chithinophagaceae are potential HMW–PAH degraders in the soil. - Abstract: Bacterial and fungal biodiversity throughout different biostimulation and bioaugmentation treatments applied to an industrial creosote-polluted soil were analyzed by means of polyphasic approach in order to gain insight into the microbial community structure and dynamics. Pyrosequencing data obtained from initial creosote polluted soil (after a biopiling step) revealed that Alpha and Gammaproteobacteria were the most abundant bacterial groups, whereas Fusarium and Scedosporium were the main fungal genera in the contaminated soil. At the end of 60-days laboratory scale bioremediation assays, pyrosequencing and DGGE data showed that (i) major bacterial community shifts were caused by the type of mobilizing agent added to the soil and, to a lesser extent, by the addition of lignocellulosic substrate; and (ii) the presence of the non-ionic surfactant (Brij 30) hampered the proliferation of Actinobacteria (Mycobacteriaceae) and Bacteroidetes (Chitinophagaceae) and, in the absence of lignocellulosic substrate, also impeded polycyclic aromatic hydrocarbons (PAHs) degradation. The results show the importance of implementing bioremediation experiments combined with microbiome assessment to gain insight on the effect of crucial parameters (e.g. use of additives) over the potential functions of complex microbial communities harbored in polluted soils, essential for bioremediation success

  9. Fe-phyllosilicate redox cycling organisms from a redox transition zone in Hanford 300 Area sediments

    Directory of Open Access Journals (Sweden)

    Jason eBenzine

    2013-12-01

    Full Text Available Microorganisms capable of reducing or oxidizing structural iron (Fe in Fe-bearing phyllosilicate minerals were enriched and isolated from a subsurface redox transition zone at the Hanford 300 Area site in eastern Washington, USA. Both conventional and in situ i-chip enrichment strategies were employed. One Fe(III-reducing Geobacter (G. bremensis strain R1, Deltaproteobacteria and six Fe(II phyllosilicate-oxidizing isolates from the Alphaproteobacteria (Bradyrhizobium japonicum strains 22, is5, and in8p8, Betaproteobacteria (Cupriavidus necator strain A5-1, Dechloromonas agitata strain is5, and Actinobacteria (Nocardioides sp. strain in31 were recovered. The G. bremensis isolate grew by oxidizing acetate with the oxidized form of NAu-2 smectite as the electron acceptor. The Fe(II-oxidizers grew by oxidation of chemically reduced smectite as the energy source with nitrate as the electron acceptor. The Bradyrhizobium isolates could also carry out aerobic oxidation of biotite. This is the first report of the recovery of a Fe(II-oxidizing Nocardioides, and to date only one other Fe(II-oxidizing Bradyrhizobium is known. The 16S rRNA gene sequences of the isolates were similar to ones found in clone libraries from Hanford 300 sediments and groundwater, suggesting that such organisms may be present and active in situ. Whole genome sequencing of the isolates is underway, the results of which will enable comparative genomic analysis of mechanisms of extracellular phyllosilicate Fe redox metabolism, and facilitate development of techniques to detect the presence and expression of genes associated with microbial phyllosilicate Fe redox cycling in sediments.

  10. Population structure of manganese-oxidizing bacteria in stratified soils and properties of manganese oxide aggregates under manganese-complex medium enrichment.

    Directory of Open Access Journals (Sweden)

    Weihong Yang

    Full Text Available Manganese-oxidizing bacteria in the aquatic environment have been comprehensively investigated. However, little information is available about the distribution and biogeochemical significance of these bacteria in terrestrial soil environments. In this study, stratified soils were initially examined to investigate the community structure and diversity of manganese-oxidizing bacteria. Total 344 culturable bacterial isolates from all substrata exhibited Mn(II-oxidizing activities at the range of 1 µM to 240 µM of the equivalent MnO2. The high Mn(II-oxidizing isolates (>50 mM MnO2 were identified as the species of phyla Actinobacteria, Firmicutes and Proteobacteria. Seven novel Mn(II-oxidizing bacterial genera (species, namely, Escherichia, Agromyces, Cellulomonas, Cupriavidus, Microbacterium, Ralstonia, and Variovorax, were revealed via comparative phylogenetic analysis. Moreover, an increase in the diversity of soil bacterial community was observed after the combined enrichment of Mn(II and carbon-rich complex. The phylogenetic classification of the enriched bacteria represented by predominant denaturing gradient gel electrophoresis bands, was apparently similar to culturable Mn(II-oxidizing bacteria. The experiments were further undertaken to investigate the properties of the Mn oxide aggregates formed by the bacterial isolates with high Mn(II-oxidizing activity. Results showed that these bacteria were closely encrusted with their Mn oxides and formed regular microspherical aggregates under prolonged Mn(II and carbon-rich medium enrichment for three weeks. The biotic oxidation of Mn(II to Mn(III/IV by these isolates was confirmed by kinetic examinations. X-ray diffraction assays showed the characteristic peaks of several Mn oxides and rhodochrosite from these aggregates. Leucoberbelin blue tests also verified the Mn(II-oxidizing activity of these aggregates. These results demonstrated that Mn oxides were formed at certain amounts under the

  11. MAPEAMENTO TECNOLÓGICO DO PROCESSO DE OBTENÇÃO DO PHB ATRAVÉS DA ANÁLISE DE PEDIDOS DE PATENTES

    Directory of Open Access Journals (Sweden)

    Larissa Alves de Sousa Costa

    2013-06-01

    Full Text Available Os polihidroxialcanoatos (PHAs são os únicos polímeros de origem microbiana totalmente biodegradável. Eles são sintetizados por diversos microrganismos, possuindo, após extração, propriedades semelhantes ao polipropileno. O polihidroxibutirato (PHB é o polímero mais comum da família dos PHAs e historicamente é o que tem sido mais estudado, ele é obtido a partir da bactéria Cupriavidus necator por fermentação da glicose em meio limitante de fonte de nitrogênio ou fósforo. Devido à importância econômica deste biopolímero, o objetivo deste trabalho foi analisar as potencialidades, características e evolução das competências tecnológicas, traduzidas através de documentos de patentes, no que diz respeito à obtenção do PHB no período de 1979 a 2010. Para tanto, foram analisados banco de dados do Espacenet, do Derwent Innovations Index, do United States Patent and Trademark Office e do Instituto Nacional de Propriedades Industrial. Foram realizadas buscas em relação à evolução anual das patentes depositadas, a origem da tecnologia, os detentores da tecnologia e principais inventores. Os códigos de Classificação Internacional de Patentes de maior incidência no Espacenet e no INPI são das classes C12 (bioquímica e mutações de engenharia genética e C08L (composições de compostos orgânicos macromoleculares, respectivamente. Nas bases pesquisadas, as empresas depositaram mais documentos que as universidades e os centros de pesquisa, sendo os anos de 2006 e 2009 os de maior relevância. Dos países pesquisados, os Estados Unidos foi o que apresentou maior número de registros (34%. O Brasil ainda possui poucas patentes na área, sendo necessários mais incentivos que visem aumentar o cenário inovativo do país.

  12. Uso de filtros de carvão ativado granular associado a microrganismos para remoção de fármacos no tratamento de água de abastecimento

    Directory of Open Access Journals (Sweden)

    Rívea Medri Borges

    Full Text Available RESUMO O modo de vida das sociedades modernas originou o aporte diário, nos ambientes aquáticos, de fármacos e outras inúmeras moléculas de uso contínuo, compostos emergentes, com potencial de risco à saúde humana principalmente pela exposição em razão da inevitável contaminação dos mananciais de abastecimento de água e da transferência para as estações de tratamento de água (ETA, onde não são removidos. O uso de carvão ativado granular na filtração demonstra ser uma opção viável para ETA, porém, uma eficiência satisfatória requer regeneração periódica do material, onerando o tratamento. Contudo, observa-se que em baixas taxas de filtração a colonização natural dos filtros por microrganismos - formação de biofilme - pode ser uma alternativa para aumentar o tempo de vida útil do carvão, bem como para decompor essas moléculas complexas em elementos minerais assimiláveis, reintroduzindo-os nos ciclos biogeoquímicos naturais. Este trabalho avaliou, durante 24 semanas, em condições de laboratório, o carvão ativado com biofilme como meio filtrante para remoção dos fármacos: diclofenaco de sódio, ibuprofeno, naproxeno e amoxicilina; experimentou em sistema batch o potencial dos microrganismos colonizadores de filtros em degradar os fármacos testados, assim como identificou filogeneticamente os microrganismos predominantes na biodegradação. Os resultados demonstram a remoção dos fármacos acima de 80%. Constatou-se a presença das bactérias dos gêneros Bacillus , Burkholderia , Cupriavidus , Pseudomonas , Shinella , e Sphingomonas . Este estudo permite inferir a capacidade de remoção de fármacos por bactérias presentes em filtros de carvão ativado e o possível uso dessa tecnologia como alternativa de controle e remoção dessas substâncias no tratamento de água potável.

  13. Thermophilic Coenzyme B12-Dependent Acyl Coenzyme A (CoA) Mutase from Kyrpidia tusciae DSM 2912 Preferentially Catalyzes Isomerization of (R)-3-Hydroxybutyryl-CoA and 2-Hydroxyisobutyryl-CoA.

    Science.gov (United States)

    Weichler, Maria-Teresa; Kurteva-Yaneva, Nadya; Przybylski, Denise; Schuster, Judith; Müller, Roland H; Harms, Hauke; Rohwerder, Thore

    2015-07-01

    The recent discovery of a coenzyme B12-dependent acyl-coenzyme A (acyl-CoA) mutase isomerizing 3-hydroxybutyryl- and 2-hydroxyisobutyryl-CoA in the mesophilic bacterium Aquincola tertiaricarbonis L108 (N. Yaneva, J. Schuster, F. Schäfer, V. Lede, D. Przybylski, T. Paproth, H. Harms, R. H. Müller, and T. Rohwerder, J Biol Chem 287:15502-15511, 2012, http://dx.doi.org/10.1074/jbc.M111.314690) could pave the way for a complete biosynthesis route to the building block chemical 2-hydroxyisobutyric acid from renewable carbon. However, the enzyme catalyzes only the conversion of the stereoisomer (S)-3-hydroxybutyryl-CoA at reasonable rates, which seriously hampers an efficient combination of mutase and well-established bacterial poly-(R)-3-hydroxybutyrate (PHB) overflow metabolism. Here, we characterize a new 2-hydroxyisobutyryl-CoA mutase found in the thermophilic knallgas bacterium Kyrpidia tusciae DSM 2912. Reconstituted mutase subunits revealed highest activity at 55°C. Surprisingly, already at 30°C, isomerization of (R)-3-hydroxybutyryl-CoA was about 7,000 times more efficient than with the mutase from strain L108. The most striking structural difference between the two mutases, likely determining stereospecificity, is a replacement of active-site residue Asp found in strain L108 at position 117 with Val in the enzyme from strain DSM 2912, resulting in a reversed polarity at this binding site. Overall sequence comparison indicates that both enzymes descended from different prokaryotic thermophilic methylmalonyl-CoA mutases. Concomitant expression of PHB enzymes delivering (R)-3-hydroxybutyryl-CoA (beta-ketothiolase PhaA and acetoacetyl-CoA reductase PhaB from Cupriavidus necator) with the new mutase in Escherichia coli JM109 and BL21 strains incubated on gluconic acid at 37°C led to the production of 2-hydroxyisobutyric acid at maximal titers of 0.7 mM. Measures to improve production in E. coli, such as coexpression of the chaperone MeaH and repression of

  14. Waste cooking oil as substrate for biosynthesis of poly(3-hydroxybutyrate and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate: Turning waste into a value-added product

    Directory of Open Access Journals (Sweden)

    Yang, T. A.

    2013-01-01

    Full Text Available Aims: Improper disposal of domestic wastes, such as waste cooking oil (WCO, contributes to the deterioration of the environment and may lead to health problems. In this study, we evaluated the potential of plant-based WCO as a carbon source for the commercial biosynthesis of the bio-plastics, poly(3-hydroxybutyrate and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate. The consumption of WCO for this purpose would mitigate their pollution of the environment at the same time.Methodology and Results: WCO collected from several cafeterias in USM was tested as the carbon source for polyhydroxyalkanoates (PHA production. A selection of suitable nitrogen source was first conducted in order to obtain an acceptable number of dry cell weight (DCW and PHA content. Urea was found to be a suitable nitrogen source for the two bacterial strains used in our study, Cupriavidus necator H16 and its transformed mutant, C. necator PHB¯4 harboring the PHA synthase gene of Aeromonas caviae (PHB¯4/pBBREE32d13. With WCO as the sole carbon source, C. necator H16 yielded a relatively good dry cell weight (DCW=25.4 g/L, with 71 wt% poly(3-hydroxybutyrate P(3HBcontent. In comparison, the DCW obtained with fresh cooking oil (FCO was 24.8 g/L. The production of poly(3 hydroxybutyrate-co-3- hydroxyhexanoate [P(3HB-co-3HHx] from WCO by the transformant C. necator PHB¯4 was comparable, yielding a DCW of 22.3 g/L and P(3HB-co-3HHx content of 85 wt%. Lipase activities for both bacterial strains reached a maximum after 72 h of cultivation when time profile was conducted. Conclusion, significance and impact of study: The use of WCO as a carbon source in the biosynthesis of the bioplastic, PHA, turns a polluting domestic waste into a value-added biodegradable product. This renewable source material can thus be exploited for the low cost production of PHA.

  15. Diversity and Efficiency of Rhizobia Communities from Iron Mining Areas Using Cowpea as a Trap Plant

    Directory of Open Access Journals (Sweden)

    Jordana Luísa de Castro

    2017-08-01

    Atlantic Forest, and as low in the rehabilitated area revegetated with grass; and the pH, with intermediate acidity level in the rehabilitated area revegetated with grass, high level of acidity in the iron outcrops and neotropical savanna, and very high acidity in the Atlantic Forest. After isolation of the nodules, 380 bacterial strains were obtained and separated into 27 groups by cultural characterization analysis. Genetic diversity was evaluated by the 16S rRNA gene partial sequencing of 156 strains, which identified some bacteria belonging to nitrogen-fixing Leguminosae nodulating bacterial genera (Rhizobium, Bradyrhizobium, Burkholderia, and Cupriavidus, some representative of associative bacteria (Bacillus, Paenibacillus, Herbaspirillum, Pseudomonas, and Agrobacterium, and other genera (Brevibacillus, Novosphingobium, Chitinophaga, Dyella, Acinetobacter, and Stenotrophomonas. The highest genetic diversity of bacteria was found in the rehabilitated area revegetated with grass indicated that it was effective in soil rehabilitation

  16. Bacteria as Potential Indicators of Heavy Metal Contamination in a Tropical Mangrove and the Implications on Environmental and Human Health

    Directory of Open Access Journals (Sweden)

    Melanie De La Rosa-Acosta

    2015-09-01

    Full Text Available Heavy metal (HM exposure has been associated with human health diseases like cancer, kidney and liver damage, neurological disorders, motor skills, low bone density and learning problems. With the beginning of the industrialization, the heavy metals in high concentration contribute to putting on the risk the humans in the vicinity. Our study site is located in Cataño, Puerto Rico. This is a highly industrialized area. It is surrounded by a recreational park, a rum distillery, two thermoelectric factories, and was impacted by CAPECO (oil refinery explosion in 2009. Las Cucharillas marsh is part of The San Juan Bay Estuary System, considered as a critical wildlife area. The mangrove marsh has three of the four mangrove species found in PR Laguncularia racemosa, Avicennia germinans and Rhizophora mangle . This study was aimed at seven different heavy metals: Arsenic (As, Cadmium (Cd, Chromium (Cr, Lead (Pb, Zinc (Zn, Mercury (Hg and Copper (Cu. These metals at high concentrations are of human health concern due to their toxicity, persistence, bioaccumulative and bio magnification potentials. Contamination of surface sediments with HM affects the food chain, starting with marine organisms up to humans. The people who live near the contaminated area and the local fishermen are at high risk of exposure. Studies reveal that certain microorganisms can resist the toxicity of heavy metals even at high concentrations. Our study pretends to exploit the sensitive nature of some bacteria to HM and use them as bioindicators. The objective of this research is to assess the bacterial community on the mangrove marsh, identify these bacteria and correlate bacterial species with the type and concentration of the metals found on the site. Our preliminary results with the BIOLOG® identification were five bacteria that are: Carnobacterium inhibens , Cupriavidus gilardii, Enterococcus maloduratus , Microbacterium flavescens and Ralstonia pickettii . This study will

  17. Solubilisation of inorganic phosphates by inoculant strains from tropical legumes

    Directory of Open Access Journals (Sweden)

    Leandro Marciano Marra

    2011-10-01

    Full Text Available Microbial solubilisation of low soluble inorganic phosphates is an important process contributing for the phosphorus available to plants in tropical soils. This study evaluates the ability of inoculant strains for tropical legumes to solubilise inorganic phosphates of low solubility that are found in tropical soils. Seven strains of Leguminosae nodulating bacteria (LNB were compared with one another and with a non-nodulating positive control, Burkholderia cepacia (LMG 1222T. Four of the strains are used as inoculants for cowpeas (Vigna unguiculata (Bradyrhizobium sp. UFLA 03-84; Bradyrhizobium elkani INPA 03-11B and Bradyrhizobium japonicum BR3267 or for common beans (Phaseolus vulgaris (Rhizobium tropici CIAT 899T. Rhizobium etli UFLA 02-100 and Rhizobium leguminosarum 316C10a are also efficient nodulators of beans and Cupriavidus taiwanensis LMG 19424T nodulates on Mimosa pudica. Two experiments, with solid and liquid media, were performed to determine whether the strains were able to solubilise CaHPO4, Al(H2PO43 or FePO4.2H2O. On solid GELP medium none of the strains dissolved FePO4.2H2O, but LMG 1222, UFLA 03-84 and CIAT 899 solubilised CaHPO4 particularly well. These strains, along with LMG 19424 and BR 3267, were also able to increase the solubility of Al(H2PO43. In liquid GELP medium, LMG 1222 solubilised all phosphate sources, but no legume nodulating strain could increase the solubility of Al(H2PO43. The strains CIAT 899 and UFLA 02-100 were the only legume nodulating bacteria able to solubilise the other phosphate sources in liquid media, dissolving both CaHPO4 and FePO4.2H2O. There was a negative correlation between the pH of the culture medium and the concentration of soluble phosphate when the phosphorus source was CaHPO4 or FePO4.2H2O. The contribution of these strains to increasing the phosphorus nutrition of legumes and non-legume plant species should be investigated further by in vivo experiments.

  18. [Isolation and characterization of petroleum catabolic broad-host-range plasmids from Shen-Fu wastewater irrigation zone].

    Science.gov (United States)

    Wang, Ya-Fei; Wang, Ya-Fei; Li, Hui; Li, Xiao-Bin

    2013-11-01

    Based on triparental mating, we isolated a total of eight broad host range (BHR) petroleum hydrocarbon catabolic plasmids from the soils, sediments, and wastewater samples in the Shen-Fu irrigation zone. The antibiotic resistance of the plasmids was tested, and then, the plasmids were transferred to Escherichia coli EC100. The plasmids carrying no antibiotic resistance were tagged by miniTn5 transposon consisting of antibiotic resistant genes. The PCR-based incompatibility test revealed that the pS3-2C and pS4-6G belonged to Inc P group, the pS3-2G, pW22-3G, and pA15-7G belonged to Inc N group, the pS7-2G was identified as Inc W plasmid, and the pA23-1G and pA10-1C were placed into Inc Q group. By adopting the reported PCR amplification methods of petroleum hydrocarbon-degrading catabolic genes, the petroleum-degrading capability of these BHR plasmids were preliminarily analyzed. The plasmids pS3-2G, pS7-2G, pA23-1G, pW22-3G, and pA10-1C carried aromatic ring- hydroxylating dioxygenase gene phdA and toluene monooxygenase gene touA; the plasmid pA15-7G carried touA and toluene dioxygenase gene tod; the plasmid pS3-2C carried ben, phdA, and tod; whereas the pS4-6G only carried ben. The host range test showed that all the isolated plasmids except pS3-2C could be transferred and maintained stably in the representative strains Agrobacterium tumefaciens C58, Cupriavidus necator JMP228, and E. coli EC100 of the alpha-, beta-, and gamma-Proteobacteria, respectively.

  19. Sulfur isotopic fractionation of carbonyl sulfide during degradation by soil bacteria and enzyme

    Science.gov (United States)

    Kamezaki, Kazuki; Hattori, Shohei; Ogawa, Takahiro; Toyoda, Sakae; Kato, Hiromi; Katayama, Yoko; Yoshida, Naohiro

    2017-04-01

    Carbonyl sulfide (COS) is an atmospheric trace gas that possess great potential for tracer of carbon cycle (Campbell et al., 2008). COS is taken up by vegetation during photosynthesis like absorption of carbon dioxide but COS can not emit by respiration of vegetation, suggesting possible tracer for gross primary production. However, some studies show the COS-derived GPP is larger than the estimates by using carbon dioxide flux because COS flux by photolysis and soil flux are not distinguished (e.g. Asaf et al., 2013). Isotope analysis is a useful tool to trace sources and transformations of trace gases. Recently our group developed a promising new analytical method for measuring the stable sulfur isotopic compositions of COS using nanomole level samples: the direct isotopic analytical technique of on-line gas chromatography-isotope ratio mass spectrometry (GC-IRMS) using fragmentation ions S+ enabling us to easily analyze sulfur isotopes in COS (Hattori et al., 2015). Soil is thought to be important as both a source and a sink of COS in the troposphere. In particular, soil has been reported as a large environmental sink for atmospheric COS. Bacteria isolated from various soils actively degrade COS, with various enzymes such as carbonic anhydrase and COSase (Ogawa et al., 2013) involved in COS degradation. However, the mechanism and the magnitude of bacterial contribution in terms of a sink for atmospheric COS is still uncertain. Therefore, it is important to quantitatively evaluate this contribution using COS sulfur isotope analysis. We present isotopic fractionation constants for COS by laboratory incubation experiments during degradation by soil bacteria and COSase. Incubation experiments were conducted using strains belonging to the genera Mycobacterium, Williamsia, Cupriavidus, and Thiobacillus, isolated from natural soil or activated sludge and enzyme purified from a bacteria. As a result, the isotopic compositions of OCS were increased during degradation of

  20. Sulfur isotopic analysis of carbonyl sulfide and its application for biogeochemical cycles

    Science.gov (United States)

    Hattori, Shohei; Kamezaki, Kazuki; Ogawa, Takahiro; Toyoda, Sakae; Katayama, Yoko; Yoshida, Naohiro

    2016-04-01

    Carbonyl sulfide (OCS or COS) is the most abundant gas containing sulfur in the atmosphere, with an average mixing ratio of 500 p.p.t.v. in the troposphere. OCS is suggested as a sulfur source of the stratospheric sulfate aerosols (SSA) which plays an important role in Earth's radiation budget and ozone depletion. Therefore, OCS budget should be validated for prediction of climate change, but the global OCS budget is imbalance. Recently we developed a promising new analytical method for measuring the stable sulfur isotopic compositions of OCS using nanomole level samples: the direct isotopic analytical technique of on-line gas chromatography-isotope ratio mass spectrometry (GC-IRMS) using fragmentation ions S+ (Hattori et al., 2015). The first measurement of the δ34S value for atmospheric OCS coupled with isotopic fractionation for OCS sink reactions in the stratosphere (Hattori et al., 2011; Schmidt et al., 2012; Hattori et al., 2012) explains the reported δ34S value for background stratospheric sulfate, suggesting that OCS is a potentially important source for background (nonepisodic or nonvolcanic) stratospheric sulfate aerosols. This new method measuring δ34S values of OCS can be used to investigate OCS sources and sinks in the troposphere to better understand its cycle. It is known that some microorganisms in soil can degrade OCS, but the mechanism and the contribution to the OCS in the air are still uncertain. In order to determine sulfur isotopic enrichment factor of OCS during degradation via microorganisms, incubation experiments were conducted using strains belonging to the genera Mycobacterium, Williamsia and Cupriavidus, isolated from natural soil environments (Kato et al., 2008). As a result, sulfur isotope ratios of OCS were increased during degradation of OCS, indicating that reaction for OC32S is faster than that for OC33S and OC34S. OCS degradation via microorganisms is not mass-independent fractionation (MIF) process, suggesting that this

  1. Microbial Oxidation of Hg(0) - Its Effect on Hg Stable Isotope Fractionation and Methylmercury Production

    Energy Technology Data Exchange (ETDEWEB)

    Yee, Nathan [Rutgers Univ., New Brunswick, NJ (United States); Barkay, Tamar [Rutgers Univ., New Brunswick, NJ (United States); Reinfelder, John [Rutgers Univ., New Brunswick, NJ (United States)

    2016-06-28

    Mercury (Hg) associated with mixed waste generated by nuclear weapons manufacturing has contaminated vast areas of the Oak Ridge Reservation (ORR). Neurotoxic methylmercury (MeHg) has been formed from the inorganic Hg wastes discharged into headwaters of East Fork Poplar Creek (EFPC). Thus, understanding the processes and mechanisms that lead to Hg methylation along the flow path of EFPC is critical to predicting the impacts of the contamination and the design of remedial action at the ORR. In part I of our project, we investigated Hg(0) oxidation and methylation by anaerobic bacteria. We discovered that the anaerobic bacterium Desulfovibrio desulfuricans ND132 can oxidize elemental mercury [Hg(0)]. When provided with dissolved elemental mercury, D. desulfuricans ND132 converts Hg(0) to Hg(II) and neurotoxic methylmercury [MeHg]. We also demonstrated that diverse species of subsurface bacteria oxidizes dissolved elemental mercury under anoxic conditions. The obligate anaerobic bacterium Geothrix fermentans H5, and the facultative anaerobic bacteria Shewanella oneidensis MR-1 and Cupriavidus metallidurans AE104 can oxidize Hg(0) to Hg(II) under anaerobic conditions. In part II of our project, we established anaerobic enrichment cultures and obtained new bacterial strains from the DOE Oak Ridge site. We isolated three new bacterial strains from subsurface sediments collected from Oak Ridge. These isolates are Bradyrhizobium sp. strain FRC01, Clostridium sp. strain FGH, and a novel Negativicutes strain RU4. Strain RU4 is a completely new genus and species of bacteria. We also demonstrated that syntrophic interactions between fermentative bacteria and sulfate-reducing bacteria in Oak Ridge saprolite mediate iron reduction via multiple mechanisms. Finally, we tested the impact of Hg on denitrification in nitrate reducing enrichment cultures derived from subsurface sediments from the Oak Ridge site, where nitrate is a major contaminant. We showed that there is an inverse

  2. Engineering Ralstonia eutropha for Production of Isobutanol (IBT) Motor Fuel from Carbon Dioxide, Hydrogen, and Oxygen Project Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Sinskey, Anthony J. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Worden, Robert Mark [Michigan State Univ., East Lansing, MI (United States); Brigham, Christopher [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Lu, Jingnan [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Quimby, John Westlake [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Gai, Claudia [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Speth, Daan [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Elliott, Sean [Boston Univ., MA (United States); Fei, John Qiang [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Bernardi, Amanda [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Li, Sophia [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Grunwald, Stephan [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Grousseau, Estelle [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Maiti, Soumen [Michigan State Univ., East Lansing, MI (United States); Liu, Chole [Michigan State Univ., East Lansing, MI (United States)

    2013-12-16

    This research project is a collaboration between the Sinskey laboratory at MIT and the Worden laboratory at Michigan State University. The goal of the project is to produce Isobutanol (IBT), a branched-chain alcohol that can serve as a drop-in transportation fuel, through the engineered microbial biosynthesis of Carbon Dioxide, Hydrogen, and Oxygen using a novel bioreactor. This final technical report presents the findings of both the biological engineering work at MIT that extended the native branched-chain amino acid pathway of the wild type Ralstonia eutropha H16 to perform this biosynthesis, as well as the unique design, modeling, and construction of a bioreactor for incompatible gasses at Michigan State that enabled the operational testing of the complete system. This 105 page technical report summarizing the three years of research includes 72 figures and 11 tables of findings. Ralstonia eutropha (also known as Cupriavidus necator) is a Gram-negative, facultatively chemolithoautotrophic bacteria. It has been the principle organism used for the study of polyhydroxybutyrate (PHB) polymer biosynthesis. The wild-type Ralstonia eutropha H16 produces PHB as an intracellular carbon storage material while under nutrient stress in the presence of excess carbon. Under this stress, it can accumulate approximately 80 % of its cell dry weight (CDW) as this intracellular polymer. With the restoration of the required nutrients, the cells are then able to catabolize this polymer. If extracted from the cell, this PHB polymer can be processed into biodegradable and biocompatible plastics, however for this research, it is the efficient metabolic pathway channeling the captured carbon that is of interest. R. eutropha is further unique in that it contains two carbon-fixation Calvin–Benson–Bassham cycle operons, two oxygen-tolerant hydrogenases, and several formate dehydrogenases. It has also been much studied for its ability in the presence of oxygen, to fix carbon dioxide