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Oh, Tae Jeong; Kim, In Gyu

doi:10.1023/a:1008864618091

Cited by 22 publications

(5 citation statements)

References 7 publications

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“…CadA is a pentamer of 5 dimer subunits and is involved in pH homeostasis, using protons to generate the polyamine species cadaverine through decarboxylation of free lysine residues (Kanjee et al, 2011). Polyamines have been previously implicated in IR resistance (Oh and Kim, 1998;Lee et al, 2019). It is unclear what effect the P18F mutation may have on CadA function.…”

Section: Discussionmentioning

confidence: 99%

Physiology of Highly Radioresistant Escherichia coli After Experimental Evolution for 100 Cycles of Selection

et al. 2020

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Ionizing radiation (IR) is lethal to most organisms at high doses, damaging every cellular macromolecule via induction of reactive oxygen species (ROS). Utilizing experimental evolution and continuing previous work, we have generated the most IR-resistant Escherichia coli populations developed to date. After 100 cycles of selection, the dose required to kill 99% the four replicate populations (IR9-100, IR10-100, IR11-100, and IR12-100) has increased from 750 Gy to approximately 3,000 Gy. Fitness trade-offs, specialization, and clonal interference are evident. Long-lived competing subpopulations are present in three of the four lineages. In IR9, one lineage accumulates the heme precursor, porphyrin, leading to generation of yellow-brown colonies. Major genomic alterations are present. IR9 and IR10 exhibit major deletions and/or duplications proximal to the chromosome replication terminus. Contributions to IR resistance have expanded beyond the alterations in DNA repair systems documented previously. Variants of proteins involved in ATP synthesis (AtpA), iron-sulfur cluster biogenesis (SufD) and cadaverine synthesis (CadA) each contribute to IR resistance in IR9-100. Major genomic and physiological changes are emerging. An isolate from IR10 exhibits protein protection from ROS similar to the extremely radiation resistant bacterium Deinococcus radiodurans, without evident changes in cellular metal homeostasis. Selection is continuing with no limit to IR resistance in evidence as our E. coli populations approach levels of IR resistance typical of D. radiodurans.

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Section: Discussionmentioning

confidence: 99%

Physiology of Highly Radioresistant Escherichia coli After Experimental Evolution for 100 Cycles of Selection

et al. 2020

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“…Several studies indicate that polyamines play a critical role in protecting DNA strand breaks induced by radiation and oxidative stress (9 -12). In fact, such DNA damage decreases the survivability of polyamine-deficient Escherichia coli mutant cells (11). However, the mechanisms by which this occurs are unknown.…”

Section: Preferred Binding Models For Polyamine⅐dna Complexes and Thementioning

confidence: 99%

“…They are small aliphatic polycations involved in numerous diverse biological processes, such as the ability to modulate gene expression and enzyme activities, activation of DNA synthesis, cell proliferation and differentiation, and others (1)(2)(3)(4)(5)(6)(7)(8). Other functions of polyamines have been related to DNA protection from external agents (9,10) and against radiation damage (11,12). In general, spermidine and spermine are present in millimolar concentrations in vivo, whereas putrescine levels are slightly lower (13)(14)(15).…”

mentioning

confidence: 99%

Structural Analysis of DNA Interactions with Biogenic Polyamines and Cobalt(III)hexamine Studied by Fourier Transform Infrared and Capillary Electrophoresis

Ouameur

Tajmir-Riahi

2004

Journal of Biological Chemistry

281

233

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Biogenic polyamines, such as putrescine, spermidine, and spermine are small organic polycations involved in numerous diverse biological processes. These compounds play an important role in nucleic acid function due to their binding to DNA and RNA. It has been shown that biogenic polyamines cause DNA condensation and aggregation similar to that of inorganic cobalt(III)hexamine cation, which has the ability to induce DNA conformational changes. However, the nature of the polyamine⅐DNA binding at the molecular level is not clearly established and is the subject of much controversy. In the present study the effects of spermine, spermidine, putrescine, and cobalt(III)hexamine on the solution structure of calf-thymus DNA were investigated using affinity capillary electrophoresis, Fourier transform infrared, and circular dichroism spectroscopic methods. At low polycation concentrations, putrescine binds preferentially through the minor and major grooves of double strand DNA, whereas spermine, spermidine, and cobalt(III)hexamine bind to the major groove. At high polycation concentrations, putrescine interaction with the bases is weak, whereas strong base binding occurred for spermidine in the major and minor grooves of DNA duplex. However, major groove binding is preferred by spermine and cobalt(III)hexamine cations. Electrostatic attractions between polycation and the backbone phosphate group were also observed. No major alterations of B-DNA were observed for biogenic polyamines, whereas cobalt(III)hexamine induced a partial B 3 A transition. DNA condensation was also observed for cobalt(III)hexamine cation, whereas organic polyamines induced duplex stabilization. The binding constants calculated for biogenic polyamines are K Spm ‫؍‬ 2.3 ؋ 10 5 M ؊1 , K Spd ‫؍‬ 1.4 ؋ 10 5 M ؊1 , and K Put ‫؍‬ 1.02 ؋ 10 5 M ؊1 . Two binding constants have been found for cobalt(III)hexamine with K 1 ‫؍‬ 1.8 ؋ 10 5 M ؊1 and K 2 ‫؍‬ 9.2 ؋ 10 4 M ؊1 . The Hill coefficients indicate a positive cooperativity binding for biogenic polyamines and a negative cooperativity for cobalt(III)hexamine.The biogenic polyamines putrescine [NH 2 (CH 2 ) 4 NH 2 ], spermidine [NH 2 (CH 2 ) 4 NH(CH 2 ) 3 NH 2 ], and spermine [NH 2 (C-H 2 ) 3 NH(CH 2 ) 4 NH(CH 2 ) 3 NH 2 ] (Structure 1) are the most prevalent polyamines in mammalian cells. They are small aliphatic polycations involved in numerous diverse biological processes, such as the ability to modulate gene expression and enzyme activities, activation of DNA synthesis, cell proliferation and differentiation, and others (1-8). Other functions of polyamines have been related to DNA protection from external agents (9, 10) and against radiation damage (11, 12). In general, spermidine and spermine are present in millimolar concentrations in vivo, whereas putrescine levels are slightly lower (13-15). However, the most important characteristic of polyamines within the cells is to bind nucleic acids and DNA in particular (1, 6).Polyamines also have the ability to induce DNA conformational transitions. Their bindi...

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“…Numerous experiments suggest that polyamines stabilize the right-handed, B-form double helix 7 , protect it from radiation and oxidation 8, 9 and compact and even aggregate DNA in low salt buffers 10, 11 . The multiple positively charged amine groups can certainly interact electrostatically with the negatively charged phosphates of DNA.…”

Section: Introductionmentioning

confidence: 99%

“…Numerous experiments suggest that polyamines stabilize the right-handed, B-form double helix, protect it from radiation and oxidation, , and compact and even aggregate DNA in low salt buffers. , The multiple positively charged amine groups can certainly interact electrostatically with the negatively charged phosphates of DNA. However, recent infrared spectroscopy data indicate that natural polyamines can bind in the major and minor grooves of DNA to interact with the DNA bases as well .…”

Section: Introductionmentioning

confidence: 99%

Physiological Levels of Salt and Polyamines Favor Writhe and Limit Twist in DNA

et al. 2012

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Quantitative analysis of single molecule experiments show that adding either of two natural polyamines, spermine or spermidine, produced more compact plectonemes in DNA in physiological concentrations of monovalent salt. They also promoted plectoneme formation at lower values of torsion in measurements of extension versus twist. Quantifying changes in the plectonemic DNA using some results from simple rod models suggested that exposure to polyamines reduced the radii and increased the densities of plectonemes. Thus, polyamines may limit the twist density by favoring writhe which maintains the B-form. Although polymerases may significantly stretch the double helix, denature DNA, and produce twist instead of writhe, natural polyamines stabilize base-pairing, limit twist to maintain the B-form, and promote supercoiling, which is conducive to replication and transcription and essential for DNA packaging.

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Cited by 22 publications

References 7 publications

Physiology of Highly Radioresistant Escherichia coli After Experimental Evolution for 100 Cycles of Selection

Physiology of Highly Radioresistant Escherichia coli After Experimental Evolution for 100 Cycles of Selection

Structural Analysis of DNA Interactions with Biogenic Polyamines and Cobalt(III)hexamine Studied by Fourier Transform Infrared and Capillary Electrophoresis

Physiological Levels of Salt and Polyamines Favor Writhe and Limit Twist in DNA

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