Nitrile-functionalized Hg(II)- and Ag(I)-N-heterocyclic carbene complexes: synthesis, crystal structures, nuclease and DNA binding activities

2012 ◽  
Vol 26 (12) ◽  
pp. 689-700 ◽  
Author(s):  
Rosenani A. Haque ◽  
Srinivasa Budagumpi ◽  
Sze Yii Choo ◽  
Mei Kee Choong ◽  
Bhadravathi Eswara Lokesh ◽  
...  
Keyword(s):  
Dna Binding ◽  
Crystal Structures ◽  
Carbene Complexes

Water-soluble copper(II) complexes with 4,5-dichloro-isothiazole-3-carboxylic acid and heterocyclic N-donor ligands: Synthesis, crystal structures, cytotoxicity, and DNA binding study

2020 ◽  
Vol 510 ◽  
pp. 119778 ◽  
Author(s):  
Julia A. Eremina ◽  
Elizaveta V. Lider ◽  
Taisiya S. Sukhikh ◽  
Lyubov S. Klyushova ◽  
Maria L. Perepechaeva ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Dna Binding ◽  
Crystal Structures ◽  
Water Soluble ◽  
Binding Study ◽  
Donor Ligands

Synthesis, characterization, crystal structures, enzyme inhibition, DNA binding, and electrochemical studies of zinc(II) complexes

2014 ◽  
Vol 67 (7) ◽  
pp. 1290-1308 ◽  
Author(s):  
Nida Ali ◽  
Muhammad Nawaz Tahir ◽  
Saqib Ali ◽  
Muhammad Iqbal ◽  
Khurram Shahzad Munawar ◽  
...  
Keyword(s):  
Dna Binding ◽  
Crystal Structures ◽  
Enzyme Inhibition ◽  
Electrochemical Studies

Dicationic derivatives of dinaphthotetraaza[14]annulene: synthesis, crystal structures and the preliminary evaluation of their DNA binding properties

Tetrahedron ◽  
2015 ◽  
Vol 71 (24) ◽  
pp. 4163-4173 ◽  
Author(s):  
Alicja Kaźmierska ◽  
Marlena Gryl ◽  
Katarzyna Stadnicka ◽  
Lesław Sieroń ◽  
Andrzej Eilmes ◽  
...  
Keyword(s):  
Dna Binding ◽  
Crystal Structures ◽  
Preliminary Evaluation ◽  
Binding Properties ◽  
Dna Binding Properties ◽  
Derivatives Of

scholarly journals Molecular and crystal structures of hydroxyl and ester functionalizedN-heterocyclic carbene complexes of iridium(I)

2015 ◽  
Vol 71 (a1) ◽  
pp. s437-s437
Author(s):  
Merve İzmirli ◽  
Aytaç G. Gökçe ◽  
Derya Gülcemal ◽  
Süleyman Gülcemal ◽  
Muhittin Aygün
Keyword(s):  
Crystal Structures ◽  
Carbene Complexes ◽  
Molecular And Crystal Structures

scholarly journals Probing E. coli SSB Protein-DNA topology by reversing DNA backbone polarity

2020 ◽  
Author(s):  
Alexander G. Kozlov ◽  
Timothy M. Lohman
Keyword(s):  
Dna Binding ◽  
Crystal Structures ◽  
Nearest Neighbor ◽  
Genome Maintenance ◽  
Binding Properties ◽  
Ssdna Binding ◽  
E Coli ◽  
Phosphodiester Linkage ◽  
The Individual ◽  
Dna Binding Properties

AbstractE. coli single strand (ss) DNA binding protein (SSB) is an essential protein that binds ssDNA intermediates formed during genome maintenance. SSB homo-tetramers bind ssDNA in two major modes differing in occluded site size and cooperativity. The (SSB)35 mode in which ssDNA wraps on average around two subunits is favored at low [NaCl] and high SSB to DNA ratios and displays high “unlimited”, nearest-neighbor cooperativity forming long protein clusters. The (SSB)65 mode, in which ssDNA wraps completely around four subunits of the tetramer, is favored at higher [NaCl] (> 200 mM) and displays “limited” low cooperativity. Crystal structures of E. coli SSB and P. falciparum SSB show ssDNA bound to the SSB subunits (OB-folds) with opposite polarities of the sugar phosphate backbones. To investigate whether SSB subunits show a polarity preference for binding ssDNA, we examined EcSSB and PfSSB binding to a series of (dT)70 constructs in which the backbone polarity was switched in the middle of the DNA by incorporating a reverse polarity (RP) phosphodiester linkage, either 3’-3’ or 5’-5’. We find only minor effects on the DNA binding properties for these RP constructs, although (dT)70 with a 3’-3’ polarity switch shows decreased affinity for EcSSB in the (SSB)65 mode and lower cooperativity in the (SSB)35 mode. However, (dT)70 in which every phosphodiester linkage is reversed, does not form a completely wrapped (SSB)65 mode, but rather binds EcSSB in the (SSB)35 mode, with little cooperativity. In contrast, PfSSB, which binds ssDNA only in an (SSB)65 mode and with opposite backbone polarity and different topology, shows little effect of backbone polarity on its DNA binding properties. We present structural models suggesting that strict backbone polarity can be maintained for ssDNA binding to the individual OB-folds if there is a change in ssDNA wrapping topology of the RP ssDNA.Statement of SignificanceSingle stranded (ss) DNA binding (SSB) proteins are essential for genome maintenance. Usually homo-tetrameric, bacterial SSBs bind ssDNA in multiple modes, one of which involves wrapping 65 nucleotides of ssDNA around all four subunits. Crystal structures of E. coli and P. falciparum SSB-ssDNA complexes show ssDNA bound with different backbone polarity orientations raising the question of whether these SSBs maintain strict backbone polarity in binding ssDNA. We show that both E. coli and P. falciparum SSBs can still form high affinity fully wrapped complexes with non-natural DNA containing internal reversals of the backbone polarity. These results suggest that both proteins maintain a strict backbone polarity preference, but adopt an alternate ssDNA wrapping topology.

Syntheses, crystal structures and DNA-binding studies of Cu(II) and Zn(II) complexes bearing asymmetrical aroylhydrazone ligand

2017 ◽  
Vol 1130 ◽  
pp. 818-828 ◽  
Author(s):  
Yueqin Li ◽  
Zhiwei Yang ◽  
Minya Zhou ◽  
Jing He ◽  
Xuehong Wang ◽  
...  
Keyword(s):  
Dna Binding ◽  
Crystal Structures ◽  
Binding Studies ◽  
Dna Binding Studies

Syntheses, crystal structures, DNA binding, DNA cleavage and DFT study of Co(iii) complexes involving azo-appended Schiff base ligands

2018 ◽  
Vol 42 (20) ◽  
pp. 16571-16582 ◽  
Author(s):  
Saikat Banerjee ◽  
Roumi Patra ◽  
Pravat Ghorai ◽  
Paula Brandão ◽  
Sougata Ghosh Chowdhury ◽  
...  
Keyword(s):  
Schiff Base ◽  
Dna Binding ◽  
Crystal Structures ◽  
Dna Cleavage ◽  
Dft Study ◽  
Schiff Base Ligands

Herein, we have reported three new Co(iii) complexes involving azo-appended Schiff base ligands.

scholarly journals Crystal Structures of the BlaI Repressor from Staphylococcus aureus and Its Complex with DNA: Insights into Transcriptional Regulation of the bla and mec Operons

2005 ◽  
Vol 187 (5) ◽  
pp. 1833-1844 ◽  
Author(s):  
Martin K. Safo ◽  
Qixun Zhao ◽  
Tzu-Ping Ko ◽  
Faik N. Musayev ◽  
Howard Robinson ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Dna Binding ◽  
Crystal Structures ◽  
Double Helix ◽  
Free Form ◽  
Binding Motif ◽  
Dimerization Domain ◽  
Gene Encoding ◽  
Dna Binding Sites ◽  
Dna Double Helix

ABSTRACT The 14-kDa BlaI protein represses the transcription of blaZ, the gene encoding β-lactamase. It is homologous to MecI, which regulates the expression of mecA, the gene encoding the penicillin binding protein PBP2a. These genes mediate resistance to β-lactam antibiotics in staphylococci. Both repressors can bind either bla or mec DNA promoter-operator sequences. Regulated resistance genes are activated via receptor-mediated cleavage of the repressors. Cleavage is induced when β-lactam antibiotics bind the extramembrane sensor of the sensor-transducer signaling molecules, BlaR1 or MecR1. The crystal structures of BlaI from Staphylococcus aureus, both in free form and in complex with 32 bp of DNA of the mec operator, have been determined to 2.0- and 2.7-Å resolutions, respectively. The structure of MecI, also in free form and in complex with the bla operator, has been previously reported. Both repressors form homodimers, with each monomer composed of an N-terminal DNA binding domain of winged helix-turn-helix topology and a C-terminal dimerization domain. The structure of BlaI in complex with the mec operator shows a protein-DNA interface that is conserved between both mec and bla targets. The recognition helix α3 interacts specifically with the conserved TACA/TGTA DNA binding motif. BlaI and, probably, MecI dimers bind to opposite faces of the mec DNA double helix in an up-and-down arrangement, whereas MecI and, probably, BlaI dimers bind to the same DNA face of bla promoter-operator DNA. This is due to the different spacing of mec and bla DNA binding sites. Furthermore, the flexibility of the dimeric proteins may make the C-terminal proteolytic cleavage site more accessible when the repressors are bound to DNA than when they are in solution, suggesting that the induction cascade involves bound rather than free repressor.

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