Envisaging an Effective Global Long-Term Agrobiodiversity Conservation System That Promotes and Facilitates Use.

Genebanks were established out of a recognised need not just to provide genetic variation to support breeding objectives but to prevent crop diversity from being lost entirely for future users. Such conservation objectives may have led, over the past few decades, to a gradually diminishing connection between genebanks and current users of diversity. While there continues to be large-scale distribution of germplasm from genebanks to recipients worldwide, relatively little is known or published about the detailed trends in the demand for genebank materials.

A Performance Management System for Long-Term Germplasm Conservation in CGIAR Genebanks: Aiming for Quality, Efficiency and Improvement.

UN Sustainable Development Goal 2 Target 2.5 focuses on the conservation of genetic diversity in soundly managed genebanks. In examining the term "soundly managed", it becomes quickly evident that there is much more to long-term conservation than placing samples of seeds or other germplasm in long-term conservation conditions.

Safeguarding a global seed heritage from Syria to Svalbard.

Crop diversity underpins food security and adaptation to climate change. Concerted conservation efforts are needed to maintain and make this diversity available to plant scientists, breeders and farmers. Here we present the story of the rescue and reconstitution of the unique seed collection held in the international genebank of International Center for Agricultural Research in the Dry Areas (ICARDA) in Syria.

Germplasm Acquisition and Distribution by CGIAR Genebanks.

The international collections of plant genetic resources for food and agriculture (PGRFA) hosted by 11 CGIAR Centers are important components of the United Nations Food and Agriculture Organization's global system of conservation and use of PGRFA. They also play an important supportive role in realizing Target 2.5 of the Sustainable Development Goals.

Why Seed Physiology Is Important for Genebanking.

Genebank management is a field in its own right; it is multifaceted, requiring a diverse set of skills and knowledge. Seed physiology is one area that is critical to the successful operation of seed genebanks, requiring understanding of seed quality during development and maturation, seed dormancy and germination, and seed longevity in storage of the target species. Careful management of the workflow between these activities, as seeds move from harvest to storage, and the recording and management of all relevant associated data, is key to ensuring the effective conservation of plant genetic resources.

Draping education to promote patient dignity: canadian physiotherapy student and instructor perceptions.

Purpose: To determine the perceptions of educators and students in Canadian entry-level professional physiotherapy programmes with respect to the current draping curriculum and the methods of delivery of that content and to determine if there is a need for additional draping education time and resources in these programmes.

Methods: Canadian university physiotherapy students (n=127) and educators (n=183) completed questionnaires designed by the authors. Data were collected via Survey Monkey, exported as Excel files, and analyzed using descriptive statistics and Pearson chi-square analysis.

Cytokine gene expression in splenic CD4+ and CD8+ T cell subsets of genetically resistant and susceptible chickens infected with Marek's disease virus.

T cells from the spleens of B(19)/B(19) and B(21)/B(21) chickens infected with MDV JM-16 strain were fractionated by flow cytometry at 4, 10, 21 days post infection (d.p.i.

Cytokine gene expression in splenic CD4(+) and CD8(+) T-cell subsets of chickens infected with Marek's disease virus.

Specific-pathogen free chickens were infected with the RB1B strain of Marek's disease virus (MDV) and T cells from the spleens of infected as well as age-matched controls were fractionated by flow cytometry at 4, 10, and 21 days post-infection (d.p.i.

Influence of in-feed virginiamycin on the systemic and mucosal antibody response of chickens.

Subtherapeutic and prophylactic doses of virginiamycin are capable of altering the intestinal microbiota as well as increasing several growth parameters in chickens. In spite of the fact that the microbiota plays a role in shaping the host's immune system, little information is available on the effects of in-feed antibiotics on the chicken immune system. The objective of this study was to examine the effects of an antibiotic, virginiamycin, on the development of antibody responses.

Sampling strategies and variability in fruit pulp micronutrient contents of west and central african bananas and plantains (Musa species).

The variability in fruit micronutrient contents in a selection of Central and West African Musa varieties cultivated under standardized field conditions was studied. Analysis of the within-fruit, within-hand, and within-plant as well as the between-plant variations demonstrated that both provitamin A carotenoids (pVACs) and mineral micronutrient (Fe, Zn) contents vary significantly across all sample groups. The variations in pVACs contents appear to be at least partly related to differences in the developmental status of the fruit, but the observed trends were genotype-specific.

15N isotope effects in glutamine hydrolysis catalyzed by carbamyl phosphate synthetase: evidence for a tetrahedral intermediate in the mechanism.

15N isotope effects have been measured on the hydrolysis of glutamine catalyzed by carbamyl phosphate synthetase of Escherichia coli. The isotope effect in the amide nitrogen of glutamine is 1. 0217 at 37 degrees C with the wild-type enzyme in the presence of MgATP and HCO(3)(-) (overall reaction taking place).

Photoaffinity labeling with the activator IMP and site-directed mutagenesis of histidine 995 of carbamoyl phosphate synthetase from Escherichia coli demonstrate that the binding site for IMP overlaps with that for the inhibitor UMP.

Photoaffinity labeling with IMP was used to attach covalently this activator to its binding site of Escherichia coli carbamoyl phosphate synthetase. We now identify histidine 995 of the large enzyme subunit as the amino acid that is cross-linked with IMP. The identification was carried out by comparative peptide mapping in two chromatographic systems of peptides differentially labeled with [3H]IMP and with the labeled inhibitor [14C]UMP, followed by automated Edman degradation and radiosequence analysis.

Photoaffinity labeling with UMP of lysine 992 of carbamyl phosphate synthetase from Escherichia coli allows identification of the binding site for the pyrimidine inhibitor.

UMP is a highly specific reagent for photoaffinity labeling of the allosteric inhibitor site of carbamyl phosphate synthetase (CPS) from Escherichia coli and has been found to be photoincorporated in the COOH-terminal domain of the large subunit [Rubio et al. (1991) Biochemistry 30, 1068-1075]. In the present work we identify lysine 992 as the residue that is covalently attached to UMP.

Carbamyl phosphate synthetase III, an evolutionary intermediate in the transition between glutamine-dependent and ammonia-dependent carbamyl phosphate synthetases.

The amino acid sequence of carbamyl phosphate synthetase (CPS) III from liver of spiny dogfish shark Squalus acanthias was deduced from the nucleotide sequence of its cDNA. Alignment of the derived amino acid sequence of CPS III with sequences of rat and frog CPS I and hamster CPS II reveals a high degree of amino acid identity, indicating that CPS III shares the same common ancestral genes as CPSs I and II. All of the CPSs examined show a high conservation of sequences in the adenine nucleotide binding domains and in residues that have been implicated in catalysis.

Location of the binding site for the allosteric activator IMP in the COOH-terminal domain of Escherichia coli carbamyl phosphates synthetase.

Using UV-irradiation we cross-linked IMP, the allosteric activator of E. coli carbamyl phosphate synthetase (a heterodimer of 117.7 and 41.

The influence of effectors and subunit interactions on Escherichia coli carbamoyl-phosphate synthetase studied by differential scanning calorimetry.

Differential scanning calorimetry of Escherichia coli carbamoyl-phosphate synthetase and its isolated large and small subunits reveals in each case an irreversible, kinetically controlled transition, at a temperature 14 degrees C higher for the holoenzyme than for the subunits, indicating dramatic stabilization of the subunits in the heterodimer. The deletion of the COOH-terminal 171 (mutant CarB'2373) or 385 (mutant CarB2177) residues of the large subunit results in more asymmetric transitions at a temperature 7 degrees C lower than for the wild type. The allosteric effectors IMP, UMP, and ornithine induce small reversible transitions at low temperature in the endotherm for the wild-type enzyme, but not for CarB'2373, as expected if the effectors bind in the 171-residue, COOH-terminal region.

Substitution of Glu841 by lysine in the carbamate domain of carbamyl phosphate synthetase alters the catalytic properties of the glutaminase subunit.

In previous studies a Glu841-->Lys replacement in the carbamate phosphorylating domain located in the COOH half of the synthetase subunit of Escherichia coli carbamyl phosphate synthetase was shown to reduce overall synthesis of carbamyl phosphate by 4 orders of magnitude with either glutamine or NH3 as nitrogen donor (Guillou et al., 1992). In the present study, the mutant enzyme has been further analyzed for its glutamine hydrolytic activity.

Detection of an enzyme bound gamma-glutamyl acyl ester of carbamyl phosphate synthetase of Escherichia coli.

E. coli carbamyl phosphate synthetase binds 0.2-0.

Evidence that mammalian glutamine-dependent carbamyl phosphate synthetase arose through gene fusion.

On the basis of homology, the mammalian CAD (glutamine-dependent carbamyl phosphate synthetase-aspartate transcarbamylase-dihydroorotase) gene appears to have arisen from the fusion of four separate ancestral genes. Evidence for two of these precursor genes is found in the carbamyl phosphate synthetase (CPSase) domain of CAD. In prokaryotes, such as Escherichia coli CPSase is encoded by two distinct cistrons of the carAB operon.

Mutational analysis of carbamyl phosphate synthetase. Substitution of Glu841 leads to loss of functional coupling between the two catalytic domains of the synthetase subunit.

The synthetase subunit of Escherichia coli carbamyl phosphate synthetase has two catalytic nucleotide-binding domains, one involved in the activation of HCO3- and the second in phosphorylation of carbamate. Here we show that a Glu841----Lys841 substitution in a putative ATP-binding domain located in the carboxyl half of the synthetase abolishes overall synthesis of carbamyl phosphate with either glutamine or NH3 as the nitrogen source. Measurements of partial activities indicate that while HCO3(-)-dependent ATP hydrolysis at saturating concentrations of substrate proceeds at higher than normal rates, ATP synthesis from ADP and carbamyl phosphate is nearly completely suppressed by the mutation.

Alterations in the energetics of the carbamoyl phosphate synthetase reaction by site-directed modification of the essential sulfhydryl group.

The change in reaction energetics of the bicarbonate-dependent ATPase reaction of Escherichia coli carbamoyl phosphate synthetase has been investigated for two site-directed mutations of the essential cysteine in the small subunit. Cysteine 269 has been proposed to facilitate the hydrolysis of glutamine by the formation of a glutamyl-thioester intermediate. The two mutant enzymes, C269S and C269G, along with the isolated large subunit, exhibit a 2-2.