Levitskiy S.A.,Federal Medical Biological Agency of Russian Federation |
Sycheva A.M.,Russian Academy of Medical Sciences |
Kharlampieva D.D.,Federal Medical Biological Agency of Russian Federation |
Oberto J.,French National Center for Scientific Research |
And 5 more authors.
Biochimie | Year: 2011
HU is a most abundant DNA-binding protein in bacteria. This protein is conserved either in its heterodimeric form or in one of its homodimeric forms in all bacteria, in plant chloroplasts, and in some viruses. HU protein non-specifically binds and bends DNA as a hetero- or homodimer and can participate in DNA supercoiling and DNA condensation. It also takes part in some DNA functions such as replication, recombination, and repair. HU does not recognize any specific sequences but shows some specificity to cruciform DNA and to repair intermediates, e.g., nick, gap, bulge, 3′-overhang, etc. To understand the features of HU binding to DNA and repair intermediates, a fast and easy HU proteins purification procedure is required. Here we report overproduction and purification of the HU homodimers. The method of HU purification allows obtaining a pure recombinant non-tagged protein cloned in Escherichia coli. We applied this method for purification of Acholeplasma laidlawii HU and demonstrated that this protein possesses a DNA - binding activity and is free of contaminating nuclease activity. Besides that we have shown that expression of A. laidlawii ihf-hu gene in a slow-growing hupAB E. coli strain restores the wild-type growth indicating that aclHU can perform the basic functions of E. coli HU in vivo. © 2011 Elsevier Masson SAS. All rights reserved.
Belinskaya E.A.,Federal Medical Biological Agency of Russian Federation |
Zykova G.V.,Federal Medical Biological Agency of Russian Federation |
Semenov S.Y.,Federal Medical Biological Agency of Russian Federation |
Finakov G.G.,Federal Medical Biological Agency of Russian Federation
Eurasian Soil Science | Year: 2015
The contents of polycyclic aromatic hydrocarbons (PAHs) in soil samples taken in the city of Moscow have been determined. A sixfold excess of the maximum permissible concentration (MPC) for benzo[a]pyrene has been found in 66% of the studied samples; an excess of the European standard for benzo[a]pyrene has been observed in 31% of the samples. The found weight fraction of benzo[a]pyrene in soil samples varies in the range of 10–740 μg/kg. The content of the ecotoxicant in the soil increases from west to east. The total concentrations of 10 indicative PAH compounds in the soils of Moscow are usually lower than the European standard. An excess of the European standard by 2–6 times has been noted in the Southeastern, Eastern, and Central administrative districts of Moscow, with separate sites of high contamination up to 6118 μg/kg. © 2015, Pleiades Publishing, Ltd.