Genetically Encoded, Noise-Tolerant, Auxin Biosensors in Yeast.

Auxins are crucial signaling molecules that regulate the growth, metabolism, and behavior of various organisms, most notably plants but also bacteria, fungi, and animals. Many microbes synthesize and perceive auxins, primarily indole-3-acetic acid (IAA, referred to as auxin herein), the most prevalent natural auxin, which influences their ability to colonize plants and animals. Understanding auxin biosynthesis and signaling in fungi may allow us to better control interkingdom relationships and microbiomes from agricultural soils to the human gut.

Androgen and glucocorticoid profiles throughout extended uniparental paternal care in the eastern hellbender salamander (Cryptobranchus a. alleganiensis).

The behavioral endocrinology associated with reproduction and uniparental male care has been studied in teleosts, but little is known about hormonal correlates of uniparental male care in other ectotherms. To address this gap, we are the first to document the seasonal steroid endocrinology of uniparental male hellbender salamanders during the transition from pre-breeding to nest initiation, and through the subsequent eight months of paternal care. In doing so, we investigated the correlates of nest fate and clutch size, exploring hellbenders' alignment with several endocrinological patterns observed in uniparental male fish.

Catechol-containing compounds are a broad class of protein aggregation inhibitors: Redox state is a key determinant of the inhibitory activities.

A range of neurodegenerative and related aging diseases, such as Alzheimer's disease and type 2 diabetes, are linked to toxic protein aggregation. Yet the mechanisms of protein aggregation inhibition by small molecule inhibitors remain poorly understood, in part because most protein targets of aggregation assembly are partially unfolded or intrinsically disordered, which hinders detailed structural characterization of protein-inhibitor complexes and structural-based inhibitor design. Herein we employed a parallel small molecule library-screening approach to identify inhibitors against three prototype amyloidogenic proteins in neurodegeneration and related proteinopathies: amylin, Aβ and tau.

Mutations that alter Arabidopsis flavonoid metabolism affect the circadian clock.

Flavonoids are a well-known class of specialized metabolites that play key roles in plant development, reproduction, and survival. Flavonoids are also of considerable interest from the perspective of human health, as both phytonutrients and pharmaceuticals. RNA sequencing analysis of an Arabidopsis null allele for chalcone synthase (CHS), which catalyzes the first step in flavonoid metabolism, has uncovered evidence that these compounds influence the expression of genes associated with the plant circadian clock.

The unusual cell wall of the Lyme disease spirochaete Borrelia burgdorferi is shaped by a tick sugar.

Peptidoglycan-a mesh sac of glycans that are linked by peptides-is the main component of bacterial cell walls. Peptidoglycan provides structural strength, protects cells from osmotic pressure and contributes to shape. All bacterial glycans are repeating disaccharides of N-acetylglucosamine (GlcNAc) β-(1-4)-linked to N-acetylmuramic acid (MurNAc).

A Role for Inositol Pyrophosphates in the Metabolic Adaptations to Low Phosphate in .

Phosphate is a major plant macronutrient and low phosphate availability severely limits global crop productivity. In , a key regulator of the transcriptional response to low phosphate, phosphate starvation response 1 (PHR1), is modulated by a class of signaling molecules called inositol pyrophosphates (PP-InsPs). Two closely related diphosphoinositol pentakisphosphate enzymes ( and ) are responsible for the synthesis and turnover of InsP, the most implicated molecule.

Comparative Metabolomics of Fruits and Leaves in a Hyperdiverse Lineage Suggests Fruits Are a Key Incubator of Phytochemical Diversification.

Interactions between plants and leaf herbivores have long been implicated as the major driver of plant secondary metabolite diversity. However, other plant-animal interactions, such as those between fruits and frugivores, may also be involved in phytochemical diversification. Using 12 species of , we conducted untargeted metabolomics and molecular networking with extracts of fruits and leaves.

McpT, a Broad-Range Carboxylate Chemoreceptor in Sinorhizobium meliloti.

Chemoreceptors enable the legume symbiont Sinorhizobium meliloti to detect and respond to specific chemicals released from their host plant alfalfa, which allows the establishment of a nitrogen-fixing symbiosis. The periplasmic region (PR) of transmembrane chemoreceptors act as the sensory input module for chemotaxis systems via binding of specific ligands, either directly or indirectly. S.

An Updated Perspective on Chemotaxis to Alfalfa Flavonoids.

The symbiotic interaction between leguminous plants and their cognate rhizobia allows for the fixation of gaseous dinitrogen into bioavailable ammonia. The perception of host-derived flavonoids is a key initial step for the signaling events that must occur preceding the formation of the nitrogen-fixing organ. Past work investigating chemotaxis - the directed movement of bacteria through chemical gradients - of , , and discovered chemotaxis to various organic compounds, but focused on chemotaxis to flavonoids because of their relevance to the symbiosis biochemistry.

The dynamic response of the Arabidopsis root metabolome to auxin and ethylene is not predicted by changes in the transcriptome.

While the effects of phytohormones on plant gene expression have been well characterized, comparatively little is known about how hormones influence metabolite profiles. This study examined the effects of elevated auxin and ethylene on the metabolome of Arabidopsis roots using a high-resolution 24 h time course, conducted in parallel to time-matched transcriptomic analyses. Mass spectrometry using orthogonal UPLC separation strategies (reversed phase and HILIC) in both positive and negative ionization modes was used to maximize identification of metabolites with altered levels.

Identification of MOS9 as an interaction partner for chalcone synthase in the nucleus.

Plant flavonoid metabolism has served as a platform for understanding a range of fundamental biological phenomena, including providing some of the early insights into the subcellular organization of metabolism. Evidence assembled over the past three decades points to the organization of the component enzymes as a membrane-associated complex centered on the entry-point enzyme, chalcone synthase (CHS), with flux into branch pathways controlled by competitive protein interactions. Flavonoid enzymes have also been found in the nucleus in a variety of plant species, raising the possibility of alternative, or moonlighting functions for these proteins in this compartment.

Sinorhizobium meliloti Chemoreceptor McpV Senses Short-Chain Carboxylates via Direct Binding.

is a soil-dwelling endosymbiont of alfalfa that has eight chemoreceptors to sense environmental stimuli during its free-living state. The functions of two receptors have been characterized, with McpU and McpX serving as general amino acid and quaternary ammonium compound sensors, respectively. Both receptors use a dual Cache (lcium channels and motaxis receptors) domain for ligand binding.

Exogenous Auxin Elicits Changes in the Arabidopsis thaliana Root Proteome in a Time-Dependent Manner.

Auxin is involved in many aspects of root development and physiology, including the formation of lateral roots. Improving our understanding of how the auxin response is mediated at the protein level over time can aid in developing a more complete molecular framework of the process. This study evaluates the effects of exogenous auxin treatment on the root proteome after exposure of young seedlings to auxin for 8, 12, and 24 h, a timeframe permitting the initiation and full maturation of individual lateral roots.

Evolutionary correlations in flavonoid production across flowers and leaves in the Iochrominae (Solanaceae).

Plant reproductive and vegetative tissues often use the same biochemical pathways to produce specialized metabolites. In such cases, selection acting on the synthesis of specific products in a particular tissue could result in correlated changes in other products of the pathway, both in the same tissue and in other tissues. This study examined how changes in floral anthocyanin pigmentation affect the production of other compounds of the flavonoid pathway in flowers and in leaves.

Metabolite Profiling of Soybean Seed Extracts from Near-Isogenic Low and Normal Phytate Lines Using Orthogonal Separation Strategies.

Untargeted metabolomic profiling using liquid chromatography-mass spectrometry (LC-MS) was applied to lipid-depleted methanolic extracts of soybean seeds utilizing orthogonal chromatographic separations (reversed-phase and hydrophilic interaction) in both positive and negative ionization modes. Four near-isogenic lines (NILs) differing in mutations for two genes encoding highly homologous multidrug resistant proteins (MRPs) were evaluated. The double mutant exhibited a low phytate phenotype, whereas the other three NILs, the two single mutants and the wild type, did not.

Automated Imaging and Analysis of the Hemagglutination Inhibition Assay.

The hemagglutination inhibition (HAI) assay quantifies the level of strain-specific influenza virus antibody present in serum and is the standard by which influenza vaccine immunogenicity is measured. The HAI assay endpoint requires real-time monitoring of rapidly evolving red blood cell (RBC) patterns for signs of agglutination at a rate of potentially thousands of patterns per day to meet the throughput needs for clinical testing. This analysis is typically performed manually through visual inspection by highly trained individuals.

A metabolomic assessment of NAC154 transcription factor overexpression in field grown poplar stem wood.

Several xylem-associated regulatory genes have been identified that control processes associated with wood formation in poplar. Prominent among these are the NAC domain transcription factors (NACs). Here, the putative involvement of Populus NAC154, a co-ortholog of the Arabidopsis gene SND2, was evaluated as a regulator of "secondary" biosynthetic processes in stem internode tissues by interrogating aqueous methanolic extracts from control and transgenic trees.

Surface catalyzed oxidative oligomerization of 17β-estradiol by Fe(3+)-saturated montmorillonite.

With widespread detection of endocrine disrupting compounds including hormones in wastewater, there is a need to develop cost-effective remediation technologies for their removal from wastewater. Previous research has shown that Fe(3+)-saturated montmorillonite is effective in quickly transforming phenolic organic compounds such as pentachlorophenol, phenolic acids, and triclosan via surface-catalyzed oligomerization. However, little is known about its effectiveness and reaction mechanisms when reacting with hormones.

Sinorhizobium meliloti chemoreceptor McpU mediates chemotaxis toward host plant exudates through direct proline sensing.

Bacterial chemotaxis is an important attribute that aids in establishing symbiosis between rhizobia and their legume hosts. Plant roots and seeds exude a spectrum of molecules into the soil to attract their bacterial symbionts. The alfalfa symbiont Sinorhizobium meliloti possesses eight chemoreceptors to sense its environment and mediate chemotaxis toward its host.

Immune response to live-attenuated Japanese encephalitis vaccine (JE-CV) neutralizes Japanese encephalitis virus isolates from south-east Asia and India.

Background: During clinical development of the licensed Japanese encephalitis chimeric virus vaccine (JE-CV), the neutralization capacity of vaccine-induced antibodies was assessed against the vaccine virus and against well characterized wild-type (wt) viruses isolated between 1949-1991. We assessed whether JE-CV-induced antibodies can also neutralize more recent wt Japanese encephalitis virus (JEV) isolates including a genotype 1 isolate.

Methods: Sera from 12-18 month-old children who received a single dose of JE-CV in a phase III study in Thailand and the Philippines (ClinicalTrials.

Optimization and validation of a plaque reduction neutralization test for the detection of neutralizing antibodies to four serotypes of dengue virus used in support of dengue vaccine development.

A dengue plaque reduction neutralization test (PRNT) to measure dengue serotype-specific neutralizing antibodies for all four virus serotypes was developed, optimized, and validated in accordance with guidelines for validation of bioanalytical test methods using human serum samples from dengue-infected persons and persons receiving a dengue vaccine candidate. Production and characterization of dengue challenge viruses used in the assay was standardized. Once virus stocks were characterized, the dengue PRNT(50) for each of the four serotypes was optimized according to a factorial design of experiments approach for critical test parameters, including days of cell seeding before testing, percentage of overlay carboxymethylcellulose medium, and days of incubation post-infection to generate a robust assay.

Comparative study of different sources of pertussis toxin (PT) as coating antigens in IgG anti-PT enzyme-linked immunosorbent assays.

In an effort to improve the reliability and reproducibility of serological assays for Bordetella pertussis, a collaborative study was conducted to compare four different sources of pertussis toxin (PT) as coating antigens in the immunoglobulin G (IgG) anti-PT enzyme-linked immunosorbent assay (ELISA). Four sources of PT were used as coating antigens in the IgG anti-PT ELISA in four different testing laboratories (labs A to D) to determine whether the different antigen preparations and different laboratories influenced assay results. A panel of 60 sera consisting of deidentified human specimens from previous vaccination trials of healthy adults and infants and clinical specimens from outbreak settings was tested.

Tobacco nicotine uptake permease (NUP1) affects alkaloid metabolism.

An effective plant alkaloid chemical defense requires a variety of transport processes, but few alkaloid transporters have been characterized at the molecular level. Previously, a gene fragment encoding a putative plasma membrane proton symporter was isolated, because it was coordinately regulated with several nicotine biosynthetic genes. Here, we show that this gene fragment corresponds to a Nicotiana tabacum gene encoding a nicotine uptake permease (NUP1).

International Bordetella pertussis assay standardization and harmonization meeting report. Centers for Disease Control and Prevention, Atlanta, Georgia, United States, 19-20 July 2007.

An international meeting on Bordetella pertussis assay standardization and harmonization was held at the Centers for Disease Control and Prevention (CDC), Atlanta, GA, 19-20 July 2007. The goal of the meeting was to harmonize the immunoassays used for pertussis diagnostics and vaccine evaluation, as agreed upon by academic and government researchers, regulatory authorities, vaccine manufacturers, and the World Health Organization (WHO). The primary objectives were (1) to provide epidemiologic, laboratory, and statistical background for support of global harmonization; (2) to overview the current status of global epidemiology, pathogenesis and immunology of pertussis; (3) to develop a consensus opinion on existing gaps in understanding standardization of pertussis assays used for serodiagnosis and vaccine evaluation; and (4) to search for a multicenter process for addressing these priority gaps.

Cloning and characterization of a Nicotiana tabacum methylputrescine oxidase transcript.

The oxidative deamination of N-methylputrescine is an essential step in both pyridine and tropane alkaloid biosynthesis. Reverse genetic approaches have not resulted in the cloning of a methylputrescine oxidase gene (MPO). However, we have used a homology-based approach to clone a full-length tobacco MPO1 cDNA.