DNA protection

Table 2. DNA protection efficiency in comparision with the control (%) in the presence of various alkylresorcinols at UV-irradiation for 300 seconds. - P<0.05.

So this research reveals new mechanisms of bacterial autoregulation under extreme conditions, controlled by low weight molecules - alkyiresorcinols. It applied aspects are defined by developing of methods for DNA protection in vitro and elongators of bacterial cells viability at UV exposure. 

PORRiNi M and Riso P (2000) Lymphocyte lycopene concentration and DNA protection from oxidative damage is increased in women after a short period of tomato consumption. JNutr 130(2) 189-92. 

The iron storage protein ferritin is a small 20 kDa a-helical protein that spontaneously assembles into a hollow ball-like homo-24-mer. The outer diameter of the sphere is circa 12 nm and the inner diameter, or core diameter, is circa 8 nm. A smaller version, known as miniferritin or Dps protein (Dps = DNA protecting... 

Su, M., Cavallo, S., Stefanini, S., Chiancone, E. and Chasteen, N.D. (2005) The so-called Listeria inocua ferritin is a Dps protein. Iron incorporation, detoxification and DNA protection properties. Biochemistry, 44, 5572-5578. 

LPDI nanoparticles are homogenous, self-forming spheres between 100 and 200 nm in diameter that are formed from the spontaneous rearrangement of a lipid bilayer around a polycation condensed DNA core. The LPDI particles (lipopolyplexes) have benefits over lipoplexes, which are composed of liposomes and DNA. Homogenous particles are formed during preparation and thus allow a more consistent production of particles, as required by the FDA for clinical use. The LPDI particles also have a lower toxicity associated with them as opposed to lipoplexes, which can generate severe systemic inflammatory responses, most likely to the increased DNA content on the surface of the particles. The internalization of DNA inside the LPDI also has a benefit of DNA protection. The DNA is not nearly as accessible to nuclease attack and mechanical stress. Therefore, a lower quantity of DNA is used because it is protected inside of the LPDI for delivery. 

Direct-Acting Defense Chemicals — Mitotic Inhibitors and DNA Protectants... 

Cationic lipids are often combined with neutral and zwitterionic lipids in formulations for gene therapy. The most frequent colipids are cholesterol, DOPE and dioleoylphosphatidylcholine (DOPC) (or other PCs) (Fig. 28). These neutral lipids may play a role in transfection by increasing the level of DNA protection against DNases or facilitating the destabilization of the endosomes [35,103]. The optimum cationic lipid/helper lipid stoichiometry varies for the different cationic lipids, nucleic acids, and cells. 

Figure 9.32. Protection by Methylation. The recognition sequence for EcoKV endonuclease (left) and the sites of methylation (right) in DNA protected from the catalytic action of the enzyme.

Among the acceptors modified by 5 -adenosylmethionine are specific bases in DNA. The methylation of DNA protects bacterial DNA from cleavage by restriction enzymes (Section 9.3). The base to be methylated is flipped out of the DNA double helix into the active site where it can accept a methyl group from 5 -adenosylmethionine (Figure 24.15). A recurring 5 -adenosylmethionine-binding domain is present in many SAM-dependent methylases. 

---