cospectrality of two graphs measures the differences between the ordered spectrum of these graphs in various ways. actually,the origin of this concept came back to richard brualdi's problems that are proposed in cite{braldi}:let $g_n$ and $g'_n$ be two nonisomorphic simple graphs on $n$ vertices with spectra$$lambda_1 geq lambda_2 geq cdots geq lambda_n ;;;text{and};;; lambda'_1 geq lambda'_2 g...

Let $P(G,lambda)$ be the chromatic polynomial of a graph $G$. A graph $G$ ischromatically unique if for any graph $H$, $P(H, lambda) = P(G,lambda)$ implies $H$ is isomorphic to $G$. In this paper, we determine the chromaticity of all Tur'{a}n graphs with at most three edges deleted. As a by product, we found many families of chromatically unique graphs and chromatic equivalence classes of graph...

lambda-exonuclease participates in DNA recombination and repair. It binds a free end of double-stranded DNA and degrades one strand in the 5' to 3' direction. The primary sequence does not appear to be related to any other protein, but the crystal structure shows part of lambda-exonuclease to be similar to the type II restriction endonucleases PvuII and EcoRV. There is also a weaker corresponde...

The thermostable properties of the DNA polymerase activity from Thermus aquaticus (Taq) have contributed greatly to the yield, specificity, automation, and utility of the polymerase chain reaction method for amplifying DNA. We report the cloning and expression of Taq DNA polymerase in Escherichia coli. From a lambda gt11:Taq library we identified a Taq DNA fragment encoding an epitope of Taq DN...

The RNA sequences boxA, boxB and boxC constitute the nut regions of phage lambda. They nucleate the formation of a termination-resistant RNA polymerase complex on the lambda chromosome. The complex includes E. coli proteins NusA, NusB, NusG and NusE, and the lambda N protein. A complex that includes the Nus proteins and other factors forms at the rrn leader. Whereas RNA-binding by NusB and NusE...

A strategy for targeting protein kinases with large ATP-binding sites by using bulky and rigid octahedral ruthenium complexes as structural scaffolds is presented. A highly potent and selective GSK3 and Pim1 half-sandwich complex NP309 was successfully converted into a PAK1 inhibitor by making use of the large octahedral compounds Lambda-FL172 and Lambda-FL411 in which the cyclopentadienyl moie...

Folding of protein-like heteropolymers into unique 3D structures is investigated using Monte Carlo simulations on a cubic lattice. We found that folding time of chains of length $N$ scales as $N^\lambda$ at temperature of fastest folding. For chains with random sequences of monomers $\lambda \approx 6$, and for chains with sequences designed to provide a pronounced minimum of energy to their gr...

Following the movement of individual molecules of a bacterial surface protein in vivo we investigated the effects of antibiotics and antimicrobial peptides on protein motility and membrane structure. In previous work we engineered the lambda-receptor of Escherichia coli such that less than one receptor per cell is in vivo biotinylated and can bind to a streptavidin coated bead. Such a bead serv...