scholarly journals Detection and Characterization of Conjugative Degradative Plasmids in Xenobiotic-Degrading Sphingomonas Strains

2004 ◽  
Vol 186 (12) ◽  
pp. 3862-3872 ◽  
Author(s):  
Tamara Basta ◽  
Andreas Keck ◽  
Joachim Klein ◽  
Andreas Stolz
Keyword(s):  
Structural Changes ◽  
Kanamycin Resistance ◽  
Conjugative Transfer ◽  
Bacterial Strains ◽  
S1 Nuclease ◽  
Kanamycin Resistance Cassette ◽  
Large Plasmids ◽  
Almost All ◽  
Plasmid Rearrangements

ABSTRACT A systematic survey for the presence of plasmids in 17 different xenobiotic-degrading Sphingomonas strains was performed. In almost all analyzed strains, two to five plasmids with sizes of about 50 to 500 kb were detected by using pulsed-field gel electrophoresis. A comparison of plasmid preparations untreated or treated with S1 nuclease suggested that, in general, Sphingomonas plasmids are circular. Hybridization experiments with labeled gene probes suggested that large plasmids are involved in the degradation of dibenzo-p-dioxin, dibenzofuran, and naphthalenesulfonates in S. wittichii RW1, Sphingomonas sp. HH69, and S. xenophaga BN6, respectively. The plasmids which are responsible for the degradation of naphthalene, biphenyl, and toluene by S. aromaticivorans F199 (pNL1) and of naphthalenesulfonates by S. xenophaga BN6 (pBN6) were site-specifically labeled with a kanamycin resistance cassette. The conjugative transfer of these labeled plasmids was attempted with various bacterial strains as putative recipient strains. Thus, a conjugative transfer of plasmid pBN6 from S. xenophaga BN6 to a cured mutant of strain BN6 and to Sphingomonas sp. SS3 was observed. The conjugation experiments with plasmid pNL1 suggested a broader host range of this plasmid, because it was transferred without any obvious structural changes to S. yanoikuyae B1, Sphingomonas sp. SS3, and S. herbicidovorans. In contrast, major plasmid rearrangements were observed in the transconjugants after the transfer of plasmid pNL1 to Sphingomonas sp. HH69 and of pBN6 to Sphingomonas sp. SS3. No indications for the transfer of a Sphingomonas plasmid to bacteria outside of the Sphingomonadaceae were obtained.

scholarly journals Cloning and Characterization of α-Methylacyl Coenzyme A Racemase from Gordonia polyisoprenivorans VH2

2008 ◽  
Vol 74 (22) ◽  
pp. 7085-7089 ◽  
Author(s):  
Quyen Arenskötter ◽  
Jens Heller ◽  
David Dietz ◽  
Matthias Arenskötter ◽  
Alexander Steinbüchel
Keyword(s):  
Cytochrome P450 ◽  
Reverse Transcription ◽  
Kanamycin Resistance ◽  
P450 Monooxygenase ◽  
Transcription Analysis ◽  
Kanamycin Resistance Cassette ◽  
Short Chain Dehydrogenase ◽  
Gordonia Polyisoprenivorans ◽  
Rubber Degradation

ABSTRACT The mcr gene of Gordonia polyisoprenivorans VH2 is not clustered with genes required for rubber degradation. Its disruption by insertion of a kanamycin resistance cassette impaired growth on methyl-branched isoprenoids but not on linear hydrocarbons. Intact mcr from this bacterium or from Nocardia farcinica IFM 10152 complemented the mutant. Reverse transcription analysis showed similar mcr VH2 expression results during cultivation with poly(cis-1,4-isoprene) and propionate. Additional genes coding for a putative cytochrome P450 monooxygenase and a short-chain dehydrogenase/reductase involved in β-oxidation and poly(cis-1,4-isoprene) degradation were also characterized.

scholarly journals Isolation and Characterization of a Native Composite Transposon, Tn14751, Carrying 17.4 Kilobases of Corynebacterium glutamicum Chromosomal DNA

2005 ◽  
Vol 71 (1) ◽  
pp. 407-416 ◽  
Author(s):  
Masayuki Inui ◽  
Yota Tsuge ◽  
Nobuaki Suzuki ◽  
Alain A. Vert�s ◽  
Hideaki Yukawa
Keyword(s):  
Corynebacterium Glutamicum ◽  
Insertion Sequence ◽  
Kanamycin Resistance ◽  
Chromosomal Dna ◽  
Kanamycin Resistance Cassette ◽  
Isolation And Characterization ◽  
Genes Encoding ◽  
Genome Scale ◽  
Random Insertion

ABSTRACT A native composite transposon was isolated from Corynebacterium glutamicum ATCC 14751. This transposon comprises two functional copies of a corynebacterial IS31831-like insertion sequence organized as converging terminal inverted repeats. This novel 20.3-kb element, Tn14751, carries 17.4 kb of C. glutamicum chromosomal DNA containing various genes, including genes involved in purine biosynthesis but not genes related to bacterial warfare, such as genes encoding mediators of antibiotic resistance or extracellular toxins. A derivative of this element carrying a kanamycin resistance cassette, minicomposite Tn14751, transposed into the genome of C. glutamicum at an efficiency of 1.8 � 102 transformants per μg of DNA. Random insertion of the Tn14751 derivative carrying the kanamycin resistance cassette into the chromosome was verified by Southern hybridization. This work paves the way for realization of the concept of minimum genome factories in the search for metabolic engineering via genome-scale directed evolution through a combination of random and directed approaches.

scholarly journals Molecular Characterization of OXA-48-Like-Producing Enterobacteriaceae in the Czech Republic and Evidence for Horizontal Transfer of pOXA-48-Like Plasmids

2016 ◽  
Vol 61 (2) ◽  
Author(s):  
Anna Skalova ◽  
Katerina Chudejova ◽  
Veronika Rotova ◽  
Matej Medvecky ◽  
Vendula Studentova ◽  
...  
Keyword(s):  
Czech Republic ◽  
Horizontal Transfer ◽  
Sequencing Data ◽  
S1 Nuclease ◽  
The Czech Republic ◽  
Content Type ◽  
E Coli ◽  
Almost All ◽  
Sequence Types

ABSTRACT The aim of this study was to characterize the first cases and outbreaks of OXA-48-like-producing Enterobacteriaceae recovered from hospital settings in the Czech Republic. From 2013 to 2015, 22 Klebsiella pneumoniae isolates, 3 Escherichia coli isolates, and 1 Enterobacter cloacae isolate producing OXA-48-like carbapenemases were isolated from 20 patients. Four of the patients were colonized or infected by two or three different OXA-48-like producers. The K. pneumoniae isolates were classified into nine sequence types (STs), with ST101 being predominant (n = 8). The E. coli isolates were of different STs, while the E. cloacae isolate belonged to ST109. Twenty-four isolates carried bla OXA-48, while two isolates carried bla OXA-181 or bla OXA-232. Almost all isolates (n = 22) carried bla OXA-48-positive plasmids of a similar size (∼60 kb), except the two isolates producing OXA-181 or OXA-232. In an ST45 K. pneumoniae isolate and an ST38 E. coli isolate, S1 nuclease profiling plus hybridization indicated a chromosomal location of bla OXA-48. Sequencing showed that the majority of bla OXA-48-carrying plasmids exhibited high degrees of identity with the pOXA-48-like plasmid pE71T. Additionally, two novel pE71T derivatives, pOXA-48_30715 and pOXA-48_30891, were observed. The bla OXA-181-carrying plasmid was identical to the IncX3 plasmid pOXA181_EC14828, while the bla OXA-232-carrying plasmid was a ColE2-type plasmid, being a novel derivative of pOXA-232. Finally, sequencing data showed that the ST45 K. pneumoniae and ST38 E. coli isolates harbored the IS1R-based composite transposon Tn6237 containing bla OXA-48 integrated into their chromosomes. These findings underlined that the horizontal transfer of pOXA-48-like plasmids has played a major role in the dissemination of bla OXA-48 in the Czech Republic. In combination with the difficulties with their detection, OXA-48 producers constitute an important public threat.

scholarly journals Host Range of the Conjugative Transfer System of IncP-9 Naphthalene-Catabolic Plasmid NAH7 and Characterization of Its oriT Region and Relaxase

2016 ◽  
Vol 83 (1) ◽  
Author(s):  
Kouhei Kishida ◽  
Kei Inoue ◽  
Yoshiyuki Ohtsubo ◽  
Yuji Nagata ◽  
Masataka Tsuda
Keyword(s):  
Host Range ◽  
Broad Host Range ◽  
Conjugative Transfer ◽  
Bacterial Strains ◽  
Conjugation System ◽  
Independent Manner ◽  
Content Type ◽  
Catabolic Plasmid ◽  
Catabolic Plasmids

ABSTRACT NAH7 and pWW0 from gammaproteobacterial Pseudomonas putida strains are IncP-9 conjugative plasmids that carry the genes for degradation of naphthalene and toluene, respectively. Although such genes on these plasmids are well-characterized, experimental investigation of their conjugation systems remains at a primitive level. To clarify these conjugation systems, in this study, we investigated the NAH7-encoded conjugation system by (i) analyzing the origin of its conjugative transfer (oriT)-containing region and its relaxase, which specifically nicks within the oriT region for initiation of transfer, and (ii) comparing the conjugation systems between NAH7 and pWW0. The NAH7 oriT (oriT N) region was located within a 430-bp fragment, and the strand-specific nicking (nic) site and its upstream sequences that were important for efficient conjugation in the oriT N region were identified. Unlike many other relaxases, the NAH7 relaxase exhibited unique features in its ability to catalyze, in a conjugation-independent manner, the site-specific intramolecular recombination between two copies of the oriT N region, between two copies of the pWW0 oriT (oriT W) region (which is clearly different from the oriT N region), and between the oriT N and oriT W regions. The pWW0 relaxase, which is also clearly different from the NAH7 relaxase, was strongly suggested to have the ability to conjugatively and efficiently mobilize the oriT N-containing plasmid. Such a plasmid was, in the presence of the NAH7Δnic derivative, conjugatively transferable to alphaproteobacterial and betaproteobacterial strains in which the NAH7 replication machinery is nonfunctional, indicating that the NAH7 conjugation system has a broader host range than its replication system. IMPORTANCE Various studies have strongly suggested an important contribution of conjugative transfer of catabolic plasmids to the rapid and wide dissemination of the plasmid-loaded degradation genes to microbial populations. Degradation genes on such plasmids are often loaded on transposons, which can be inserted into the genomes of the recipient bacterial strains where the transferred plasmids cannot replicate. The aim was to advance detailed molecular knowledge of the determinants of host range for plasmids. This aim is expected to be easily and comprehensively achieved using an experimental strategy in which the oriT region is connected with a plasmid that has a broad host range of replication. Using such a strategy in this study, we showed that (i) the NAH7 oriT-relaxase system has unique properties that are significantly different from other well-studied systems and (ii) the host range of the NAH7 conjugation system is broader than previously thought.

scholarly journals Optimization and Molecular Characterization of Lipase Producing Bacillus subtilis Strain Rcps3 and Bacillus fumarioli Strain Rcps4 from Oil-contaminated Soils of Warangal

2020 ◽  
Vol 14 (3) ◽  
pp. 2063-2074
Author(s):  
Ramya Chouhan ◽  
Suresh Lapaka ◽  
Nagaraju Alpula ◽  
Srinivas Podeti
Keyword(s):  
Bacillus Subtilis ◽  
Contaminated Soil ◽  
Contaminated Soils ◽  
Lipase Production ◽  
Subtilis Strain ◽  
Bacterial Strains ◽  
Almost All ◽  
Bacterial Sources ◽  
Hydrolysis Of

Microbial sources are regularly used as reliable biocatalysts sources which are often used in the process and production industry. Demands for such organisms with greater capacity of intended enzyme production are on the rise. Lipase is important enzyme used in the biotechnological process of hydrolysis of fats in almost all the relevant industries We have utilized the local oil-contaminated soil resources to search for efficacious bacterial strains that have excellent lipase activity. We were successful in identifying two such bacterial sources, namely, Bacillus subtilis strain RCPS3 and Bacillus fumarioli strain RCPS4, responsible for lipase production from oil effluent contaminated soil of Telangana. This is the first report of these two strains from this part of India that are involved in lipase production. The strains were isolated, optimized, and purified using standard microbiology protocols and were characterized at the molecular level using the biomarker 16s ribosomal RNA genes of the strains. The identified and isolated bacterial strains were confirmed as Bacillus subtilis strain RCPS3, and Bacillus fumarioli strain RCPS4 through molecular and computational characterization.

A Thorough Theoretical Exploration of Intriguing Characteristics of Cyclo[18]carbon: Geometry, Bonding Nature, Aromaticity, Weak Interaction, Reactivity, Excited States, Vibrations, Molecular Dynamics and Various Molecular Properties

2019 ◽  
Author(s):  
Tian Lu ◽  
Qinxue Chen ◽  
Zeyu Liu
Keyword(s):  
Molecular Dynamics ◽  
Excited States ◽  
Electronic Excitation ◽  
Ring Structure ◽  
Molecular Properties ◽  
Molecular Vibration ◽  
Full Characterization ◽  
Long Time ◽  
Almost All

Although cyclo[18]carbon has been theoretically and experimentally investigated since long time ago, only very recently it was prepared and directly observed by means of STM/AFM in condensed phase (Kaiser et al., <i>Science</i>, <b>365</b>, 1299 (2019)). The unique ring structure and dual 18-center π delocalization feature bring a variety of unusual characteristics and properties to the cyclo[18]carbon, which are quite worth to be explored. In this work, we present an extremely comprehensive and detailed investigation on almost all aspects of the cyclo[18]carbon, including (1) Geometric characteristics (2) Bonding nature (3) Electron delocalization and aromaticity (4) Intermolecular interaction (5) Reactivity (6) Electronic excitation and UV/Vis spectrum (7) Molecular vibration and IR/Raman spectrum (8) Molecular dynamics (9) Response to external field (10) Electron ionization, affinity and accompanied process (11) Various molecular properties. We believe that our full characterization of the cyclo[18]carbon will greatly deepen researchers' understanding of this system, and thereby help them to utilize it in practice and design its various valuable derivatives.

A Thorough Theoretical Exploration of Intriguing Characteristics of Cyclo[18]carbon: Geometry, Bonding Nature, Aromaticity, Weak Interaction, Reactivity, Excited States, Vibrations, Molecular Dynamics and Various Molecular Properties

2019 ◽  
Author(s):  
Tian Lu ◽  
Qinxue Chen ◽  
Zeyu Liu
Keyword(s):  
Molecular Dynamics ◽  
Excited States ◽  
Electronic Excitation ◽  
Ring Structure ◽  
Molecular Properties ◽  
Molecular Vibration ◽  
Full Characterization ◽  
Long Time ◽  
Almost All

Although cyclo[18]carbon has been theoretically and experimentally investigated since long time ago, only very recently it was prepared and directly observed by means of STM/AFM in condensed phase (Kaiser et al., <i>Science</i>, <b>365</b>, 1299 (2019)). The unique ring structure and dual 18-center π delocalization feature bring a variety of unusual characteristics and properties to the cyclo[18]carbon, which are quite worth to be explored. In this work, we present an extremely comprehensive and detailed investigation on almost all aspects of the cyclo[18]carbon, including (1) Geometric characteristics (2) Bonding nature (3) Electron delocalization and aromaticity (4) Intermolecular interaction (5) Reactivity (6) Electronic excitation and UV/Vis spectrum (7) Molecular vibration and IR/Raman spectrum (8) Molecular dynamics (9) Response to external field (10) Electron ionization, affinity and accompanied process (11) Various molecular properties. We believe that our full characterization of the cyclo[18]carbon will greatly deepen researchers' understanding of this system, and thereby help them to utilize it in practice and design its various valuable derivatives.

Extraction and characterization of sea anemones compound and its Anti bacterial and hemolytic studies

2020 ◽  
Vol 10 (4) ◽  
pp. 93-97
Author(s):  
Anil Kumar A ◽  
Raja Sheker K ◽  
Naveen B ◽  
Abhilash G ◽  
Akila CR
Keyword(s):  
Antibacterial Activity ◽  
Focal Point ◽  
Haemolytic Activity ◽  
Klebsiella Pneumonia ◽  
Bacterial Strains ◽  
Sea Anemones ◽  
Marine Plants ◽  
Heteractis Magnifica ◽  
Trididemnum Solidum

Seas assets that give us a variety of characteristic items to control bacterial, contagious and viral ailment and mostly utilized for malignancy chemotherapy practically from spineless creatures, for example, bryozoans, wipes, delicate corals, coelenterates, ocean fans, ocean bunnies, molluscs and echinoderms. In the previous 30 - 40 years, marine plants and creatures have been the focal point of overall endeavours to characterize the regular results of the marine condition. Numerous marine characteristic items have been effectively exceptional to the last phases of clinical preliminaries, including dolastatin-10, a group of peptides disengaged from Indian ocean rabbit, Dollabella auricularia. Ecteinascidin-743 from mangrove tunicate Ecteinascidia turbinata, Didemnins was isolated from Caribbean tunicate Trididemnum solidum and Conopeptides from cone snails (Conus sp.), and a developing number of up-and-comers have been chosen as promising leads for expanded pre-clinical appraisals. Sea anemones possess numerous tentacles containing stinging cells or cnidocytes. The stinging cells are equipped with small organelles known as nematocysts. The two species of sea anemones namely, Heteractis magnificaandStichodactyla haddoni, were collected from Mandapam coastal waters of Ramanathapuram district, Tamilnadu, India. The Nematocyst was collected and centrifuged, and the supernatant was lyophilized and stored for further analysis. The amount of protein from Heteractis Magnifica and Stichodactyla haddoni was estimated. The crude extract has shown haemolytic activity on chicken blood and goat blood. In the antibacterial activity of the sea anemone against six bacterial strains Staphylococcus aureus, Salmonella typhii, Salmonella paratyphii, Klebsiella pneumonia, Vibrio cholerae, Pseudomonas aeruginosa. Antibacterial activity of H. Magnifica and S.haddoni was measured as the radius of the zone of inhibition.

Thermal characterization of ABS-Graphene blended three dimensional printed functional prototypes for electro chemical energy storage

2018 ◽  
Vol 1 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Kamaljit Singh Boparai ◽  
Rupinder Singh
Keyword(s):  
Energy Storage ◽  
Structural Changes ◽  
Fused Deposition Modeling ◽  
Morphological Changes ◽  
Three Dimensional ◽  
Thermal Characterization ◽  
Chemical Energy ◽  
Flow Index ◽  
Fused Deposition

This study highlights the thermal characterization of ABS-Graphene blended three dimensional (3D) printed functional prototypes by fused deposition modeling (FDM) process. These functional prototypes have some applications as electro-chemical energy storage devices (EESD). Initially, the suitability of ABS-Graphene composite material for FDM applications has been examined by melt flow index (MFI) test. After establishing MFI, the feedstock filament for FDM has been prepared by an extrusion process. The fabricated filament has been used for printing 3D functional prototypes for printing of in-house EESD. The differential scanning calorimeter (DSC) analysis was conducted to understand the effect on glass transition temperature with the inclusion of Graphene (Gr) particles. It has been observed that the reinforced Gr particles act as a thermal reservoir (sink) and enhances its thermal/electrical conductivity. Also, FT-IR spectra realized the structural changes with the inclusion of Gr in ABS matrix. The results are supported by scanning electron microscopy (SEM) based micrographs for understanding the morphological changes.

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