Site-specific Modification Of De Novo Designed Coiled-coil Polypeptides With Inorganic Redox Complexes

A stepwise procedure for preparing of site-specific binuclear metallopeptides is described. The modification procedure involves the alkylation of a cysteine side chain by reaction with [Ru(bpy)(2)(phen-ClA)](2+), where bpy = 2,2\u27-bipyridine and phen-ClA = 5-chloroacetaniido-1,10-phenanthroline, followed by the coordination of a ruthenium pentammine complex to a histidine residue located elsewhere along the sequence. The apo and metalated versions of the peptides C10H21(30-mer) and H10C21(30-mer) display circular dichroism spectra having minima at 208 and 222 nm, with theta(222)/theta(208) = 1.04 to indicate that these peptides exist as a-helical coiled-coils in aqueous solution. When the ruthenium polypyridyl complex is attached to C10H21(30-mer), the Delta-l and Lambda-l diastereomers of the resulting metallopeptide can be readily separated from each other by reversed-phase HPLC. However, in the case of the related H10C21(30-mer) metallopeptide, the two diastereomers cannot be chromatographically resolved. These results indicate how the subtle interplay between peptide conformation/sequence and metal complex geometry may alter some of the physical characteristics of metallopeptides

Words, Worlds and Beyond: English Lexicology in Action: Практикум із лексикології англійської мови

Посібник розроблено для студентів третього курсу спеціальності 035 ФІЛОЛОГІЯ, освітнього рівня ПЕРШИЙ (бакалаврський), освітньої програми МОВА ТА ЛІТЕРАТУРА (англійська), спеціалізація 035.04 ГЕРМАНСЬКІ МОВИ І ЛІТЕРАТУРИ (переклад включно). Посібник спрямований на ознайомлення студентів із основними питаннями лексикології англійської мови як складової частини загального мовознавства, розгляд головних напрямків і методів дослідження лексики, вивчення лексичних явищ у їх морфологічному складі, за значенням, сталими властивостями, лексико-стилістичними ознаками, походженням, діалектними розбіжностями

Organizational and Socio-Psychological Difficulties of Management of Patients with Chlamydia Infection

Lack of detection of chlamydia infection does not correspond to the high prevalence of its clinical manifestations. It is associated with a frequent asymptomatic course, the prevalence of persistent forms of infection and difficulties in their diagnosis. Unification of approaches to diagnosis and therapy of chlamydial infections without taking into account the topical diagnosis leads to insufficient therapy. It is difficult to find a balance between the need for long-term antibiotic therapy for chlamydial persistence and the dangers of its consequences. Difficulties in the treatment of chlamydia infection are also associated with socio-psychological factors: low efficiency and even inexpediency of etiotropic therapy of chlamydia in polygamous relationships, promiscuous behavior; poor synchronization of partner therapy, often treating only one partner in a couple; orientation of patients towards short-term “pill” therapy, which is not sufficiently effective for chronic persistent chlamydia with significant morphological changes in the genitals; low compliance of male partners to therapy in a couple “by contact” in the absence of clinically apparent manifestations; peculiarities of public consciousness regarding chlamydia infection. As a result, therapy often only stops exacerbations of inflammation and does not eliminate the infection completely

Photoinduced Electron-transfer Along Alpha-helical And Coiled-coil Metallopeptides

A peptide-based electron-transfer system has been designed in which the specific positions of redox-active metal complexes appended to either an a-helix, or an a-helical coiled-coil, can be reversed to test the effect of the helix dipole in controlling photoinduced electron-transfer rates. Two 30-residue apopeptides were prepared having the following sequences: (1) Ac-K-(IEALEGK)(ICALEGK)(IEALEHK)-(IEALEGK)-G-amide, and (II) Ac-K-(IEALEGK)(IHALEGK)-(IEALECK)(IEALEGK)-G-amide. Each apopeptide was reacted first with [Ru(bpy)(2)(phen-ClAc)](2+), where bpy = 2,2\u27-bipyridine and phen-ClAc = 5-chloroacetamido-1,10-phenanthroline, to attach the ruthenium polypyridyl center to the cysteine side-chain of the polypeptide. The isolated products were then reacted with [Ru(NH3)(5)(H2O)](2+) to yield the binuclear electron-transfer metallopeptides ET-I and ET-II. In these systems, electron-transfer occurred from the photoexcited ruthenium polypyridyl donor to the pentammine ruthenium (111) acceptor such that the electron-transfer occurred toward the negative end of the helix dipole in ET-I, and toward the positive end in ET-II. Circular dichroism spectroscopy showed that both peptides exist as dimeric alpha-helical coiled-coils in 100 mM phosphate buffer at pH 7, and as monomeric a-helices in the lower dielectric solvents 2,2,2-trifluoroethanol, and a 1:1 (v/v) mixture of CH2Cl2 and 2,2,2-trifluoroethanol. The peptides were predominately (i.e., 65-72%) alpha-helical in these solvents. The emission lifetime behavior of ET-I was seen to be identical to that of ET-II in each of the three solvents: no evidence for directional electron-transfer rates was observed. Possible reasons for this behavior are discussed

H216O line list for the study of atmospheres of Venus and Mars

IR spectroscopy is an important method of remote measurement of H216O content in planetary atmospheres with initial spectroscopic information from the HITRAN, GEISA, etc., databases adapted for studies in the Earth’s atmosphere. Unlike the Earth, the atmospheres of Mars and Venus mainly consist of carbon dioxide with a CO2 content of about 95%. In this paper, the line list of H216O is obtained on the basis of the BT2 line list (R.J. Barber, J. Tennyson, G.J. Harris, et al., Mon. Not. R. Astron. Soc. 368, 1087 (2006)). The BT2 line list containing information on the centers, intensities, and quantum identification of lines is supplemented with the line contour parameters: the self-broadening and carbon dioxide broadening coefficients and the temperature dependence coefficient at 296 K in the range of 0.001–30000 cm−1. Transitions with intensity values 10−30, 10−32, and 10−35 cm/molecule, the total number of which is 323310, 753529, and 2011072, respectively, were chosen from the BT2 line list