This study explores the assembly in the crystalline state of a class of pentacenes that are substituted along their long edges with aromatic rings forming rigid, cruciform molecules. The crystals were grown from the gas phase, and their structures were compared with DFT-optimized geometries. Both crystallographic and computed structures show that a planar acene core is the exception rather than...

by drawing blood through a heparin lock, patients can be protected from skin damages duo to repeated needle sticks. in addition, this procedure can assist to gain more precise results in laboratory test and to prevent further complications. probably, you have ever used a heparin lock in order to infusion of medicines but, it is possible that you never use of that for blood sampling. both two pr...

In vitro, Escherichia coli RecA protein acts upon gapped and partially homologous linear duplex DNA to generate recombination products linked by Holliday junctions. When strand exchange reactions are supplemented with purified RecBCD enzyme, we observe the formation of products that resemble "patch" recombinants. The formation of "splice" recombinant products was not observed. The individual su...

In the gene b2 of Ascobolus immersus, large heterologies increase the frequencies of reciprocal exchanges on their upstream border (corresponding to the high non-Mendelian segregation side). Tests were made to determine whether these reciprocal exchanges, instigated by large heterologies, resulted from the blockage of a Holliday junction bordering a hybrid DNA tract extending from the end of th...

OBJECTIVE The aim of this work is to demonstrate a novel single-molecule DNA sequence comparison assay that is purely based on DNA mechanics. METHODS A molecular construct that contained the two homologous but non-identical DNA sequences that were to be compared was prepared such that a four-way (Holliday) junction could be formed by the formation of heteroduplexes through the inter-recombina...

Recombination catalyzed by the Flp site-specific recombinase involves breakage and joining of four DNA strands between two target substrates. The reaction is carried out in two steps of pairwise strand exchanges by a DNA-protein assembly in which four Flp monomers act cooperatively to execute strand cleavage and joining. Two models for recombination have been proposed. In the trimer model, the ...