In vitro assessment of antimicrobial and genotoxic effect of metallosurfactant based nickel hydroxide nanoparticles against Escherichia coli and its genomic DNA

2018 ◽  
Vol 170 ◽  
pp. 99-108 ◽  
Author(s):  
Varsha Dogra ◽  
Gurpreet Kaur ◽  
Amanpuneet Kaur ◽  
Rajeev Kumar ◽  
Sandeep Kumar
Keyword(s):  
Escherichia Coli ◽  
Nickel Hydroxide ◽  
Genomic Dna ◽  
Genotoxic Effect ◽  
In Vitro Assessment ◽  
Nickel Hydroxide Nanoparticles

Guanidinium and phosphonium scaffolds loaded with silver nanoparticles: synthesis, characterization, in vitro assessment of the antibacterial potential and toxicity

2021 ◽  
Author(s):  
M. N. Gorbunova ◽  
L.M. Lemkina ◽  
A.I. Nechaev
Keyword(s):  
Escherichia Coli ◽  
Silver Nanoparticles ◽  
Uv Spectroscopy ◽  
Planktonic Cells ◽  
Silver Nanocomposites ◽  
Nanoparticles Synthesis ◽  
In Vitro Assessment ◽  
Xrd Techniques ◽  
Antibacterial Potential

Abstract New silver nanocomposites based on polysulfones of 2,2-diallyl-1,1,3,3-tetraethylguanidiniumchloride [poly(AGC-SO2)], tris(diethylamino)diallylaminophosphonium tetrafluoroborate [poly(DAAP-BF4-SO2)] and chloride [poly(DAAP-Cl-SO2)] have been developed. UV- spectroscopy, SEM and XRD techniques were used to characterize the formation of silver nanoparticles in copolymers. Antibacterial action of new silver nanocomposites on S. epidermidis 33 and Escherichia coli (planktonic cells and biofilms) was studied. The silver nanocomposites strongly inhibited biofilms formation of S. epidermidis 33 and Escherichia coli. The silver nanocomposites based on phosphonium polysulfones have a significant cytotoxic activity against RD and MS line cells.

scholarly journals Lowering S-Adenosylmethionine Levels inEscherichia coli Modulates C-to-T Transition Mutations

2001 ◽  
Vol 183 (3) ◽  
pp. 921-927 ◽  
Author(s):  
Georgina Macintyre ◽  
C. Victoria Atwood ◽  
Claire G. Cupples
Keyword(s):  
Escherichia Coli ◽  
Dna Methylation ◽  
Genomic Dna ◽  
Synthetase Activity ◽  
Inescherichia Coli ◽  
Genome Methylation ◽  
Sam Synthetase ◽  
Methyl Cytosine

ABSTRACT Deoxycytosine methylase (Dcm) enzyme activity causes mutagenesis in vitro either directly by enzyme-induced deamination of cytosine to uracil in the absence of the methyl donor,S-adenosylmethionine (SAM), or indirectly through spontaneous deamination of [5-methyl]cytosine to thymine. Using a Lac reversion assay, we investigated the contribution of the first mechanism to Dcm mutagenesis in vivo by lowering the levels of SAM.Escherichia coli SAM levels were lowered by reducing SAM synthetase activity via the introduction of a metK84 allele or by hydrolyzing SAM using the bacteriophage T3 SAM hydrolase. ThemetK84 strains exhibited increased C-to-T mutagenesis. Expression of the T3 SAM hydrolase gene, under the control of the arabinose-inducible PBAD promoter, effectively reduced Dcm-mediated genomic DNA methylation. However, increased mutagenesis was not observed until extremely high arabinose concentrations were used, and genome methylation at Dcm sites was negligible.

scholarly journals Molecular cloning and over-expression of the glyoxylate bypass operon from Escherichia coli ML308

1987 ◽  
Vol 242 (3) ◽  
pp. 661-665 ◽  
Author(s):  
E M T el-Mansi ◽  
C MacKintosh ◽  
K Duncan ◽  
W H Holms ◽  
H G Nimmo
Keyword(s):  
Escherichia Coli ◽  
Enzyme Activities ◽  
Recombinant Plasmid ◽  
Genomic Dna ◽  
Isocitrate Lyase ◽  
Malate Synthase ◽  
Structural Genes ◽  
Glyoxylate Bypass ◽  
Over Expression

A recombinant plasmid carrying an 11 kb restriction-endonuclease-ClaI fragment of genomic DNA from Escherichia coli ML308 was constructed. This plasmid complements an aceA mutation. The plasmid encodes the structural genes of the glyoxylate bypass operon, namely malate synthase A (aceB), isocitrate lyase (aceA) and isocitrate dehydrogenase kinase/phosphatase (aceK), as judged by overexpression of enzyme activities and transcription/translation experiments in vitro. Subcloning confirmed that expression of the aceK gene is essential for growth on acetate.

scholarly journals Molecular Cloning of Cyanobacterial Pteridine Glycosyltransferases That Catalyze the Transfer of either Glucose or Xylose to Tetrahydrobiopterin

2010 ◽  
Vol 76 (22) ◽  
pp. 7658-7661 ◽  
Author(s):  
Yeol Gyun Lee ◽  
Ae Hyun Kim ◽  
Mi Bi Park ◽  
Hye-Lim Kim ◽  
Kon Ho Lee ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Molecular Cloning ◽  
Environmental Samples ◽  
Genomic Dna ◽  
Pcr Amplification ◽  
Activity Assay ◽  
Genes Encoding ◽  
Cyanobacterial Genes

ABSTRACT Here, we report cloning of cyanobacterial genes encoding pteridine glycosyltransferases that catalyze glucosyl or xylosyl transfer from UDP-sugars to tetrahydrobiopterin. The genes were cloned by PCR amplification from genomic DNA which was isolated from culture and environmental samples and overexpressed in Escherichia coli for an in vitro activity assay.

TiO2-NPs and cadmium co-exposure: in vitro assessment of genetic and genomic DNA damage on Dicentrarchus labrax embryonic cells

2021 ◽  
Author(s):  
Filomena Mottola ◽  
Marianna Santonastaso ◽  
Concetta Iovine ◽  
Giada Frenzilli ◽  
Simona Picchietti ◽  
...  
Keyword(s):  
Dna Damage ◽  
Genomic Dna ◽  
Dicentrarchus Labrax ◽  
Embryonic Cells ◽  
Tio2 Nps ◽  
In Vitro Assessment

scholarly journals Photoreactivation of Escherichia coli after Low- or Medium-Pressure UV Disinfection Determined by an Endonuclease Sensitive Site Assay

2002 ◽  
Vol 68 (12) ◽  
pp. 6029-6035 ◽  
Author(s):  
Kumiko Oguma ◽  
Hiroyuki Katayama ◽  
Shinichiro Ohgaki
Keyword(s):  
Escherichia Coli ◽  
Uv Irradiation ◽  
Genomic Dna ◽  
Uv Disinfection ◽  
E Coli ◽  
Medium Pressure ◽  
Pyrimidine Dimers ◽  
Sensitive Site ◽  
Uv Lamp

ABSTRACT Photoreactivation of Escherichia coli after inactivation by a low-pressure (LP) UV lamp (254 nm), by a medium-pressure (MP) UV lamp (220 to 580 nm), or by a filtered medium-pressure (MPF) UV lamp (300 to 580 nm) was investigated. An endonuclease sensitive site (ESS) assay was used to determine the number of UV-induced pyrimidine dimers in the genomic DNA of E. coli, while a conventional cultivation assay was used to investigate the colony-forming ability (CFA) of E. coli. In photoreactivation experiments, more than 80% of the pyrimidine dimers induced by LP or MPF UV irradiation were repaired, while almost no repair of dimers was observed after MP UV exposure. The CFA ratios of E. coli recovered so that they were equivalent to 0.9-, 2.3-, and 1.7-log inactivation after 3-log inactivation by LP, MP, and MPF UV irradiation, respectively. Photorepair treatment of DNA in vitro suggested that among the MP UV emissions, wavelengths of 220 to 300 nm reduced the subsequent photorepair of ESS, possibly by causing a disorder in endogenous photolyase, an enzyme specific for photoreactivation. On the other hand, the MP UV irradiation at wavelengths between 300 and 580 nm was observed to play an important role in reducing the subsequent recovery of CFA by inducing damage other than damage to pyrimidine dimers. Therefore, it was found that inactivating light at a broad range of wavelengths effectively reduced subsequent photoreactivation, which could be an advantage that MP UV irradiation has over conventional LP UV irradiation.

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