4-[(E)-(4-Methyl­phen­yl)imino­meth­yl]phenol

In the title compound, C14H13NO, the two rings show significant deviation from coplanarity, with a dihedral angle between the two planes of 49.40 (5)°. The hy­droxy group is involved in an inter­molecular O—H⋯N hydrogen bond, forming an extended one-dimensional zigzag chain along (001)

4-Bromo-N-(4-hy­droxy­benzyl­idene)­aniline

In the title compound, C13H10BrNO, the benzene ring planes are inclined at an angle of 48.85 (17)°, resulting in a nonplanar mol­ecule. A characteristic of aromatic Schiff bases with N-aryl substituents is that the terminal phenyl rings are twisted relative to the HC=N plane. In this case, the HC=N unit makes dihedral angles of 11.1 (4) and 38.5 (3)° with the hy­droxy­benzene and bromo­benzene rings, respectively. In the crystal, the molecules are linked by O—H⋯N hydrogen bonds to form infinite (C8) chains along the b axis

Differences in evolutionary pressure acting within highly conserved ortholog groups

<p>Abstract</p> <p>Background</p> <p>In highly conserved widely distributed ortholog groups, the main evolutionary force is assumed to be purifying selection that enforces sequence conservation, with most divergence occurring by accumulation of neutral substitutions. Using a set of ortholog groups from prokaryotes, with a single representative in each studied organism, we asked the question if this evolutionary pressure is acting similarly on different subgroups of orthologs defined as major lineages (e.g. Proteobacteria or Firmicutes).</p> <p>Results</p> <p>Using correlations in entropy measures as a proxy for evolutionary pressure, we observed two distinct behaviors within our ortholog collection. The first subset of ortholog groups, called here informational, consisted mostly of proteins associated with information processing (i.e. translation, transcription, DNA replication) and the second, the non-informational ortholog groups, mostly comprised of proteins involved in metabolic pathways. The evolutionary pressure acting on non-informational proteins is more uniform relative to their informational counterparts. The non-informational proteins show higher level of correlation between entropy profiles and more uniformity across subgroups.</p> <p>Conclusion</p> <p>The low correlation of entropy profiles in the informational ortholog groups suggest that the evolutionary pressure acting on the informational ortholog groups is not uniform across different clades considered this study. This might suggest "fine-tuning" of informational proteins in each lineage leading to lineage-specific differences in selection. This, in turn, could make these proteins less exchangeable between lineages. In contrast, the uniformity of the selective pressure acting on the non-informational groups might allow the exchange of the genetic material via lateral gene transfer.</p

Ultrasensitive and selective non-enzymatic electrochemical glucose sensor based on hybrid material of graphene nanosheets/graphene nanoribbons/nickel nanoparticle

A fast, highly sensitive and selective non-enzymatic electrochemical glucose sensor based on graphene sheet/graphene nanoribbon/nickel nanoparticles (GS/GNR/Ni) hybrid material modified electrode was fabricated. The hybrid material was synthesized via facile in-situ chemical reduction and characterized by X-ray diffraction, transmission electron microscopy, Raman spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The GS/GNR/Ni/GCE showed high electrochemical activity towards the oxidation of glucose in a 0.1 M NaOH solution. At an applied potential of +0.5 V, it displayed wide linear amperometric response towards glucose from the range of 5 nM–5 mM, with a detection limit of 2.5 nM and sensitivity of 2.3 mA/mM cm 2 . Moreover, the modified electrode was relatively insensitive to commonly interfering species such as dopamine, ascorbic acid, sucrose, uric acid and Cl - ions. The fabricated sensor with better reproducibility, good long term stability, makes it a promising electrode for the development of effective glucose sensor

Biochemical polymorphism studies in breeds of wool-sheep, hair-sheep and their hybrids in Malaysia

A biochemical genetic study on bolld enzyme/protein systems in some breeds/crosses of sheep in Malaysia was carried out using horizontal starch elelectrophoresis. Blood samples were collected from 435 sheep, representing 8 breeds/crosses. These included 5 wool sheep breeds (Thai Longtail, Wiltshire, Suffolk, Dorsimal and cMBLx), 1 hair sheep breed (Barbados Blackbelly) and 2 hybreds between wool sheep and hair sheep (Cameroon x Thai Longtail and Bali Bali x Malin). Twenty loci systems were examined. Of these, ten (HBβ, ALB, TF, XP, CAT, DIAI, EsA, GPI, ME and NP) exhibited genetic variation whereas the other ten (AAT, CA, DIA2, αGLO, αGLU, LDH, MDH, PEP[leu-gly-gly], 6PGD and SOD) were monomorphic. The allelic frequencies which were obtained in 10 polymorphic markers are assessed and compared with the results obtained by previous workers. The estimations of inbreeding coefficient, intrabreed variation and breed relationships have been critically discussed and are used to reveal some important recommendations

Evaluation of INSeq To Identify Genes Essential for

The reciprocal interaction between rhizosphere bacteria and their plant hosts results in a complex battery of genetic and physiological responses. In this study, we used insertion sequencing (INSeq) to reveal the genetic determinants responsible for the fitness of Pseudomonas aeruginosa PGPR2 during root colonization. We generated a random transposon mutant library of Pseudomonas aeruginosa PGPR2 comprising 39,500 unique insertions and identified genes required for growth in culture and on corn roots. A total of 108 genes were identified as contributing to the fitness of strain PGPR2 on roots. The importance in root colonization of four genes identified in the INSeq screen was verified by constructing deletion mutants in the genes and testing them for the ability to colonize corn roots singly or in competition with the wild type. All four mutants were affected in corn root colonization, displaying 5- to 100-fold reductions in populations in single inoculations, and all were outcompeted by the wild type by almost 100-fold after seven days on corn roots in mixed inoculations of the wild type and mutant. The genes identified in the screen had homology to genes involved in amino acid catabolism, stress adaptation, detoxification, signal transduction, and transport. INSeq technology proved a successful tool to identify fitness factors in P aeruginosa PGPR2 for root colonization

Comparison of phylogenetic trees through alignment of embedded evolutionary distances

<p>Abstract</p> <p>Background</p> <p>The understanding of evolutionary relationships is a fundamental aspect of modern biology, with the phylogenetic tree being a primary tool for describing these associations. However, comparison of trees for the purpose of assessing similarity and the quantification of various biological processes remains a significant challenge.</p> <p>Results</p> <p>We describe a novel approach for the comparison of phylogenetic distance information based on the alignment of representative high-dimensional embeddings (xCEED: Comparison of Embedded Evolutionary Distances). The xCEED methodology, which utilizes multidimensional scaling and Procrustes-related superimposition approaches, provides the ability to measure the global similarity between trees as well as incongruities between them. We demonstrate the application of this approach to the prediction of coevolving protein interactions and demonstrate its improved performance over the mirrortree, tol-mirrortree, phylogenetic vector projection, and partial correlation approaches. Furthermore, we show its applicability to both the detection of horizontal gene transfer events as well as its potential use in the prediction of interaction specificity between a pair of multigene families.</p> <p>Conclusions</p> <p>These approaches provide additional tools for the study of phylogenetic trees and associated evolutionary processes. Source code is available at <url>http://gomezlab.bme.unc.edu/tools</url>.</p

Genomic analysis reveals a tight link between transcription factor dynamics and regulatory network architecture

Although several studies have provided important insights into the general principles of biological networks, the link between network organization and the genome-scale dynamics of the underlying entities (genes, mRNAs, and proteins) and its role in systems behavior remain unclear. Here we show that transcription factor (TF) dynamics and regulatory network organization are tightly linked. By classifying TFs in the yeast regulatory network into three hierarchical layers (top, core, and bottom) and integrating diverse genome-scale datasets, we find that the TFs have static and dynamic properties that are similar within a layer and different across layers. At the protein level, the top-layer TFs are relatively abundant, long-lived, and noisy compared with the core- and bottom-layer TFs. Although variability in expression of top-layer TFs might confer a selective advantage, as this permits at least some members in a clonal cell population to initiate a response to changing conditions, tight regulation of the core- and bottom-layer TFs may minimize noise propagation and ensure fidelity in regulation. We propose that the interplay between network organization and TF dynamics could permit differential utilization of the same underlying network by distinct members of a clonal cell population