Neutron and Gamma-Radiation Sensitivity of Plasmid DNA of Varying Superhelical Density

AbstractThe effects of seven gamma radiation dosages from 5 to 100 krad on all metamorphic stages of the spider beetle, Gibbium psylloides (Czenpinski), were studied. Five kilorads prevented development of adults from treated eggs and larvae. Some adults emerged from the pupal cocoon at all treatment levels except 50 and 100 krad, but their longevity was greatly reduced. Adults were fairly resistant to sterilizing effects of the radiation. Twenty kilokrads was not completely sterilizing to either males or females, but fecundity was greatly reduced. The longevity of treated adults was significantly reduced, but some survived for 20 weeks after a 20-krad exposure. Adults and pupae of this species were more radiation resistant than were most other stored-product Coleoptera.

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Gamma Radiation Sensitivity of Enterobacter sakazakii in Dehydrated Powdered Infant Formula

Journal of Food Protection ◽

10.4315/0362-028x-69.6.1434 ◽

2006 ◽

Vol 69 (6) ◽

pp. 1434-1437 ◽

Cited By ~ 18

Author(s):

J. W. LEE ◽

S. H. OH ◽

J. H. KIM ◽

H. S. YOOK ◽

M. W. BYUN

Keyword(s):

Radiation Dose ◽

Gamma Radiation ◽

Infant Formula ◽

Marked Effect ◽

Radiation Sensitivity ◽

Sensory Properties ◽

Hot Water ◽

Powdered Infant Formula ◽

Enterobacter Sakazakii ◽

Nutritional Studies

The observed Enterobacter sakazakii D10-values for tryptic soy broth and dehydrated powdered infant formula were 0.27 ± 0.05 and 0.76 ± 0.08 kGy, respectively. A decrease of approximately 3 log in the dehydrated powdered infant formula was obtained by irradiation with 3.0 kGy or rehydration with hot water at 80°C. No recoverable bacteria were found in the powdered infant formula irradiated at 5.0 kGy and stored, either before or after rehydration. A radiation dose of up to 5.0 kGy had no marked effect on the sensory properties of the dehydrated powdered infant formula after rehydration and heating. Gamma radiation could potentially be used to inactivate E. sakazakii in dehydrated powdered infant formula; however, nutritional studies need to be conducted before the use of radiation can be recommended.

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Application of Plasmid Engineering to Enhance Yield and Quality of Plasmid for Vaccine and Gene Therapy

Bioengineering ◽

10.3390/bioengineering6020054 ◽

2019 ◽

Vol 6 (2) ◽

pp. 54

Author(s):

Folarin ◽

Nesbeth ◽

Ward ◽

Keshavarz-Moore

Keyword(s):

Plasmid Dna ◽

Downstream Processing ◽

Point Of View ◽

High Yield ◽

Bacteriophage Mu ◽

E Coli ◽

Yield And Quality ◽

Superhelical Density ◽

High Level ◽

Binding Sequence

There is an increased interest in plasmid DNA as therapeutics. This is evident in the number of ongoing clinical trials involving the use of plasmid DNA. In order to be an effective therapeutic, high yield and high level of supercoiling are required. From the bioprocessing point of view, the supercoiling level potentially has an impact on the ease of downstream processing. We approached meeting these requirements through plasmid engineering. A 7.2 kb plasmid was developed by the insertion of a bacteriophage Mu strong gyrase-binding sequence (Mu-SGS) to a 6.8 kb pSVβ-Gal and it was used to transform four different E. coli strains, and cultured in order to investigate the Mu-SGS effect and dependence on strain. There was an increase of over 20% in the total plasmid yield with pSVβ-Gal398 in two of the strains. The supercoiled topoisomer content was increased by 5% in both strains leading to a 27% increase in the overall yield. The extent of supercoiling was examined using superhelical density (σ) quantification with pSVβ-Gal398 maintaining a superhelical density of −0.022, and pSVβ-Gal −0.019, in both strains. This study has shown that plasmid modification with the Mu-phage SGS sequence has a beneficial effect on improving not only the yield of total plasmid but also the supercoiled topoisomer content of therapeutic plasmid DNA during bioprocessing.

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Incorporation of 5-substituted uracil derivatives into nucleic acids. The isolation and γ-radiation-sensitivity of bacteriophage T3 containing the thymine analogue 5-vinyluracil

Biochemical Journal ◽

10.1042/bj1870257 ◽

1980 ◽

Vol 187 (1) ◽

pp. 257-260 ◽

Cited By ~ 1

Author(s):

E T J Chelton ◽

M Duggan ◽

R N Hunston ◽

A S Jones ◽

M K O'Leary ◽

...

Keyword(s):

Escherichia Coli ◽

Nucleic Acids ◽

Gamma Radiation ◽

Radiation Sensitivity ◽

Γ Radiation ◽

Uracil Derivatives ◽

Phage Dna

Bacteriophage T3 was produced in a form that contained 32% of its normal DNA thymine residues replaced with 5-vinyluracil residues by infecting a thymine-requiring strain of Escherichia coli with phage T3 in a medium containing 5-vinyluracil. When 2′-deoxy-5-vinyluridine was added to the medium instead, no incorporation was observed into the phage DNA, and the presence of the deoxyribonucleoside severely decreased the number of viable phage particles produced. The analogue-containing phage, although initially viable, rapidly lost viability when stored, but it was no more sensitive than was normal phage T3 to the effect of gamma-radiation.

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Gamma radiation sensitivity of larvae and adults of the red flour beetle, Tribolium castaneum Herbst

Anzeiger für Schädlingskunde ◽

10.1007/s10340-003-0002-9 ◽

2003 ◽

Vol 76 (5) ◽

pp. 129-132 ◽

Cited By ~ 2

Author(s):

A. S. Tun�bilek ◽

A. Ayvaz ◽

F. �zt�rk ◽

B. Kaplan

Keyword(s):

Gamma Radiation ◽

Tribolium Castaneum ◽

Radiation Sensitivity ◽

Red Flour Beetle ◽

Flour Beetle

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In Vitro Effects of Gamma Radiation from 60Co and 137Cs on Plasmid DNA

Journal of Biological Physics ◽

10.1007/s10867-007-9050-3 ◽

2007 ◽

Vol 33 (2) ◽

pp. 155-160 ◽

Cited By ~ 8

Author(s):

F. M. Milian ◽

A. N. Gouveia ◽

M. R. Gual ◽

J. O. Echeimberg ◽

J. D. T. Arruda-Neto ◽

...

Keyword(s):

Gamma Radiation ◽

Plasmid Dna ◽

In Vitro Effects

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Gamma radiation sensitivity in Nigella sativa L.

CYTOLOGIA ◽

10.1508/cytologia.51.609 ◽

1986 ◽

Vol 51 (3) ◽

pp. 609-615 ◽

Cited By ~ 6

Author(s):

Animesh K. Datta ◽

Amal K. Biswas ◽

Subir Sen

Keyword(s):

Gamma Radiation ◽

Nigella Sativa ◽

Radiation Sensitivity

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Gamma Radiation Sensitivity of Different Stages of Saw-Toothed Grain Beetle Oryzaephilus Surinamensis L. (Coleoptera: Silvanidae)

Journal of Plant Protection Research ◽

10.2478/v10045-010-0044-y ◽

2010 ◽

Vol 50 (3) ◽

pp. 250-255 ◽

Cited By ~ 9

Author(s):

Abbas Hosseinzadeh ◽

Nouraddin Shayesteh ◽

Hamid Zolfagharieh ◽

Mohammad Babaei ◽

Hasan Zareshahi ◽

...

Keyword(s):

Gamma Radiation ◽

Gamma Rays ◽

Developmental Stages ◽

Growth Index ◽

Adult Emergence ◽

Radiation Sensitivity ◽

Oryzaephilus Surinamensis ◽

Larval Emergence ◽

Dose Dependent Increase ◽

Dose Dependent

Gamma Radiation Sensitivity of Different Stages of Saw-Toothed Grain BeetleOryzaephilus SurinamensisL. (Coleoptera: Silvanidae)The effect of gamma irradiation on different developmental stages ofOryzaephilus surinamensisL., was investigated. Results showed that a required dose to prevent larval emergence from irradiated 1-2-days-old eggs was 60 Gray (Gy), and 350 Gy was required to prevent adult emergence from 15-days-old larvae. Also the required dose of radiation to prevent adult emergence from irradiated 5-days-old pupa was 700 Gy. The dose of 200 Gy caused 100% mortality of irradiated adults 28 days after treatment. In addition, the effect of gamma rays was studied on the developmental stage period of each irradiated stage till adult emergence. The results revealed that there was a dose-dependent increase of the developmental periods. The growth index of adults was significantly decreased with increasing dose of radiation administered to eggs, larvae and pupae. It is recommended that doses between 600 and 700 Gy should be used to control population growth ofO. surinamensiswhen targeting pupae and adults present in stored products.

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