bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Arabidopsis Mutant with High Cyclic Electron Flow around Photosystem I (hcef) Involving the NADPH Dehydrogenase Complex
Authors: Livingston Aaron K. , Cruz Jeffrey A. , Kohzuma Kaori , Dhingra Amit , Kramer David M. 
Published: January 2010

Abstract
Cyclic electron flow (CEFI) has been proposed to balance the chloroplast energy budget, but the pathway, mechanism, and physiological role remain unclear. We isolated a new class of mutant in Arabidopsis thaliana, hcef for high CEF1, which shows constitutively elevated CEF1. The first of these, hcef1, was mapped to chloroplast fructose-1,6-bisphosphatase. Crossing hcef1 with pgr5, which is deficient in the antimycin A–sensitive pathway for plastoquinone reduction, resulted in a double mutant that maintained the high CEF1 phenotype, implying that the PGR5-dependent pathway is not involved. By contrast, crossing hcef1 with crr2-2, deficient in thylakoid NADPH dehydrogenase (NDH) complex, results in a double mutant that is highly light sensitive and lacks elevated CEF1, suggesting that NDH plays a direct role in catalyzing or regulating CEF1. Additionally, the NdhI component of the NDH complex was highly expressed in hcef1, whereas other photosynthetic complexes, as well as PGR5, decreased. We propose that (1) NDH is specifically upregulated in hcef1, allowing for increased CEF1; (2) the hcef1 mutation imposes an elevated ATP demand that may trigger CEF1; and (3) alternative mechanisms for augmenting ATP cannot compensate for the loss of CEF1 through NDH.
Structures of human MST3 kinase in complex with adenine, ADP and Mn2+
Authors: Ko Tzu-Ping , Jeng Wen-Yih , Liu Chia-I , Lai Ming-Derg , Wu Chun-Lan , Chang Wei-Jung , Shr Hui-Lin , Lu Te-Jung , Wang Andrew H.-J. 
Published: January 2010

The MST family is a subclass of mammalian serine/threonine kinases that are related to the yeast sterile-20 protein and are implicated in regulating cell growth and transformation. The MST3 protein contains a 300-residue catalytic domain and a 130-residue regulatory domain, which can be cleaved by caspase and activated by autophosphorylation, promoting apoptosis. Here, five crystal structures of the catalytic domain of MST3 are presented, including a complex with ADP and manganese, a unique cofactor preferred by the enzyme, and a complex with adenine. Similar to other protein kinases, the catalytic domain of MST3 folds into two lobes: the smaller N lobe forms the nucleotide-binding site and the larger C lobe recognizes the polypeptide substrate. The bound ADP and Mn2+ions are covered by a glycine-rich loop and held in place by Asn149 and Asp162. A different orientation was observed for the ligand in the MST3–adenine complex. In the activation loop, the side chain of Thr178 is phosphorylated and is sandwiched by Arg143 and Arg176. Comparison of this structure with other similar kinase structures shows a 180° rotation of the loop, leading to activation of the enzyme. The well defined protein–ligand interactions also provide useful information for the design of potent inhibitors.
Structure of grouper iridovirus purine nucleoside phosphorylase
Authors: Kang You-Na , Zhang Yang , Allan Paula W. , Parker William B. , Ting Jing-Wen , Chang Chi-Yao , Ealick Steven E. 
Published: January 2010

Purine nucleoside phosphorylase (PNP) catalyzes the reversible phosphorolysis of purine ribonucleosides to the corresponding free bases and ribose 1-phosphate. The crystal structure of grouper iridovirus PNP (givPNP), corresponding to the first PNP gene to be found in a virus, was determined at 2.4 Å resolution. The crystals belonged to space groupR3, with unit-cell parametersa= 193.0,c= 105.6 Å, and contained four protomers per asymmetric unit. The overall structure of givPNP shows high similarity to mammalian PNPs, having an α/β structure with a nine-stranded mixed β-barrel flanked by a total of nine α-helices. The predicted phosphate-binding and ribose-binding sites are occupied by a phosphate ion and a Tris molecule, respectively. The geometrical arrangement and hydrogen-bonding patterns of the phosphate-binding site are similar to those found in the human and bovine PNP structures. The enzymatic activity assay of givPNP on various substrates revealed that givPNP can only accept 6-oxopurine nucleosides as substrates, which is also suggested by its amino-acid composition and active-site architecture. All these results suggest that givPNP is a homologue of mammalian PNPs in terms of amino-acid sequence, molecular mass, substrate specificity and overall structure, as well as in the composition of the active site.
Complexes ofThermotoga maritimaS-adenosylmethionine decarboxylase provide insights into substrate specificity
Authors: Bale Shridhar , Baba Kavita , McCloskey Diane E. , Pegg Anthony E. , Ealick Steven E. 
Published: January 2010

The polyamines putrescine, spermidine and spermine are ubiquitous aliphatic cations and are essential for cellular growth and differentiation.S-Adenosylmethionine decarboxylase (AdoMetDC) is a critical pyruvoyl-dependent enzyme in the polyamine-biosynthetic pathway. The crystal structures of AdoMetDC from humans and plants and of the AdoMetDC proenzyme fromThermotoga maritimahave been obtained previously. Here, the crystal structures of activatedT. maritimaAdoMetDC (TmAdoMetDC) and of its complexes withS-adenosylmethionine methyl ester and 5′-deoxy-5′-dimethylthioadenosine are reported. The results demonstrate for the first time that TmAdoMetDC autoprocesses without the need for additional factors and that the enzyme contains two complete active sites, both of which use residues from both chains of the homodimer. The complexes provide insights into the substrate specificity and ligand binding of AdoMetDC in prokaryotes. The conservation of the ligand-binding mode and the active-site residues between human andT. maritimaAdoMetDC provides insight into the evolution of AdoMetDC.
Pseudo-merohedral twinning and noncrystallographic symmetry in orthorhombic crystals of SIVmac239 Nef core domain bound to different-length TCRζ fragments
Authors: Kim Walter M. , Sigalov Alexander B. , Stern Lawrence J. 
Published: January 2010

HIV/SIV Nef mediates many cellular processes through interactions with various cytoplasmic and membrane-associated host proteins, including the signalling ζ subunit of the T-cell receptor (TCRζ). Here, the crystallization strategy, methods and refinement procedures used to solve the structures of the core domain of the SIVmac239 isolate of Nef (Nefcore) in complex with two different TCRζ fragments are described. The structure of SIVmac239 Nefcorebound to the longer TCRζ polypeptide (Leu51–Asp93) was determined to 3.7 Å resolution (Rwork= 28.7%) in the tetragonal space groupP43212. The structure of SIVmac239 Nefcorein complex with the shorter TCRζ polypeptide (Ala63–Arg80) was determined to 2.05 Å resolution (Rwork = 17.0%), but only after the detection of nearly perfect pseudo-merohedral crystal twinning and proper assignment of the orthorhombic space groupP212121. The reduction in crystal space-group symmetry induced by the truncated TCRζ polypeptide appears to be caused by the rearrangement of crystal-contact hydrogen-bonding networks and the substitution of crystallographic symmetry operations by similar noncrystallographic symmetry (NCS) operations. The combination of NCS rotations that were nearly parallel to the twin operation (k, h, −l) andaandbunit-cell parameters that were nearly identical predisposed theP212121crystal form to pseudo-merohedral twinning.
Structure of human desArg-C5a
Authors: Cook William J. , Galakatos Nicholas , Boyar William C. , Walter Richard L. , Ealick Steven E. 
Published: January 2010

The anaphylatoxin C5a is derived from the complement component C5 during activation of the complement cascade. It is an important component in the pathogenesis of a number of inflammatory diseases. NMR structures of human and porcine C5a have been reported; these revealed a four-helix bundle stabilized by three disulfide bonds. The crystal structure of human desArg-C5a has now been determined in two crystal forms. Surprisingly, the protein crystallizes as a dimer and each monomer in the dimer has a three-helix core instead of the four-helix bundle noted in the NMR structure determinations. Furthermore, the N-terminal helices of the two monomers occupy different positions relative to the three-helix core and are completely different from the NMR structures. The physiological significance of these structural differences is unknown.
Managing product variety in emerging markets
Authors: Felipe Scavarda Luiz , Reichhart Andreas , Hamacher Silvio , Holweg Matthias 
Published: January 2010

PurposeThe need for an efficient provision of product variety has been widely established as a means of competing in the marketplace, yet previous studies into the management of product variety have commonly analysed products in isolated developed markets. The purpose of this paper is to investigate how firms manage their product variety in emerging markets. This paper aims to investigate the rationale underlying the restriction of variety in such settings, and define general mechanisms by which firms can adapt their product variety when operating in both emerging and developed markets simultaneously.Design/methodology/approachThe paper uses the case of a global vehicle manufacturer that offers common products across developed and emerging markets to illustrate the difference between them in terms of product variety, and examine the process that underlies its management. The paper utilises a combination of data collection techniques.FindingsThe paper shows empirically how product variety (in particular ex factory variety) is restricted in emerging markets, as one would expect, and it identifies the mechanisms by which product variety is managed across different markets. The paper further illustrates how emerging markets have developed secondary coping mechanisms to deliver additional variety through late configuration in the distribution system.Originality/valueBy examining the differential management of product variety in emerging and developed markets, the findings yield several novel aspects by providing both empirical evidence and explanations for the restriction of product variety in emerging markets.
Radical economics and our current predicament
Authors: Armour Leslie 
Published: January 2010

PurposeThe purpose of this paper is to introduce the “Radical economics” issue in International Journal of Social Economics.Design/methodology/approach“Radical economics” has two basic meanings. One employs the basic sense of “radical”, whatever goes to the roots of the matter. The other common meaning of radical has to do with whatever diverges from the orthodoxy of the time. This issue examines radical economics in both senses.FindingsThe recent world economic crisis raises basic questions about economic thought. Complex mathematical formulae led banks to take what proved to be unwarranted risks. Behind them is a tendency to regard economics as a self‐contained discipline. Complexities which sociologists, social psychologists, anthropologists and historians have done something to unravel are sometimes simply ignored. The philosophical bases of the economic theories in circulation are often more than two centuries old. But some important ideas from the past have been forgotten, the distinction between wealth and riches is one. Social change also plays a part in the problems. Community friendly capitalism, ridiculed and attacked by some economists, has faded. At a deeper level the tendency for the rich to get much richer while the poorest people in the world are only slightly better off has produced more instability and uncertainty, which economists have not successfully addressed.Practical implicationsIt is hoped readers will join in these ongoing explorations.Social implicationsThe recent economic crisis has been importantly a crisis of confidence. Economic studies, which offer hope for change, can be an element in increasing confidence.Originality/valueThe problem posed by the constant expansion necessitated in the ordinary way the need to invest profits may threaten the sustainability of life on our planet and no immediately available economic theory seems to address this. This issue begins to raise the essential questions, with hopes of continuing the discussion.
Applying western organization development in China: lessons from a case of success
Authors: Wang Jia 
Published: January 2010

PurposeThe purpose of this paper is to explore a successful case of a Chinese state‐owned enterprise (SOE) as it applied western organization development (OD) approaches. Specifically, this study seeks to answer two questions: How has western organization development and change (OD/C) been applied in one Chinese SOE? and What lessons can be learned from this successful case?Design/methodology/approachThe paper employs a single case design to gain an in‐depth understanding. The case study is the methodology when the focus is on a contemporary phenomenon within a real‐life context.FindingsThe findings reveal that the organization successfully uses a number of western OD techniques in creating a shared vision, establishing a performance‐based human resource management system, and standardizing budgetary and cost control procedures. The success of the company's change effort is largely attributed to leadership, standardization of management systems, commitment to learning and training, and partnership with an OD expert.Research limitations/implicationsFindings of this paper are limited by the single case study design. Future research is needed to study more cases of success where western OD techniques have been applied. Further research is also warranted to identify indigenous OD approaches used by Chinese organizations. Current research also needs to be expanded to study regions or countries that are undergoing similar economic transitions and have adopted western‐based OD techniques.Originality/valueBy focusing on an under‐explored research territory – China – the paper expands the current knowledge of OD into the international domain and fills in the gap of OD/C research which is lacking in China.
Phylogeny of the millipede order Spirobolida (Arthropoda: Diplopoda: Helminthomorpha)
Authors: Pitz Kevin M. , Sierwald Petra 
Published: January 2010

AbstractThis study examines relationships within the millipede order Spirobolida using an exemplar approach, sampling within families to maximize geographical and morphological diversity; due to lack of available material, Allopocockiidae and Hoffmanobolidae were not included in analyses. The focus of this study was to test monophyly of the order, the suborders, and the families of Spirobolida and to propose interfamilial relationships using morphological and molecular data in a total‐evidence approach. Both maximum‐parsimony analyses and Bayesian inference were employed to analyse two datasets consisting of combined morphological and molecular data, one aligned using progressive alignment methods and the second aligned by secondary structure models. Rhinocricidae was recovered sister to all remaining spirobolidan millipedes and is elevated to suborder status as suborder Rhinocricidea. Trigoniulidea was recovered as monophyletic as was Spirobolidea excluding Rhinocricidae; Spirobolidea is redefined to reflect this change. All previously recognized families were recovered, with the exception of Spirobolidae; in all instances, this family was paraphyletic or part of a polytomy that lacked sufficient resolution to assess its monophyly. The results reaffirm much of the existing taxonomic foundation within Spirobolida. This study provides the first phylogenetic test of higher‐level relationships within Spirobolida and will serve as a foundation for future work in this group at finer levels. © The Willi Hennig Society 2010.
A genome‐wide scan for signatures of recent selection in Holstein cattle
Authors: Qanbari S. , Pimentel E. C. G. , Tetens J. , Thaller G. , Lichtner P. , Sharifi A. R. , Simianer H. 
Published: January 2010

SummaryThe data from the newly available 50 K SNP chip was used for tagging the genome‐wide footprints of positive selection in Holstein–Friesian cattle. For this purpose, we employed the recently described Extended Haplotype Homozygosity test, which detects selection by measuring the characteristics of haplotypes within a single population. To assess formally the significance of these results, we compared the combination of frequency and the Relative Extended Haplotype Homozygosity value of each core haplotype with equally frequent haplotypes across the genome. A subset of the putative regions showing the highest significance in the genome‐wide EHH tests was mapped. We annotated genes to identify possible influence they have in beneficial traits by using the Gene Ontology database. A panel of genes, including FABP3, CLPN3, SPERT, HTR2A5, ABCE1, BMP4 and PTGER2, was detected, which overlapped with the most extreme P‐values. This panel comprises some interesting candidate genes and QTL, representing a broad range of economically important traits such as milk yield and composition, as well as reproductive and behavioural traits. We also report high values of linkage disequilibrium and a slower decay of haplotype homozygosity for some candidate regions harbouring major genes related to dairy quality. The results of this study provide a genome‐wide map of selection footprints in the Holstein genome, and can be used to better understand the mechanisms of selection in dairy cattle breeding.
Comparison of intravenous immune globulin and high dose anti‐D immune globulin as initial therapy for childhood immune thrombocytopenic purpura
Authors: Kane Ian , Ragucci Dominic , Shatat Ibrahim F. , Bussel James , Kalpatthi Ram 
Published: January 2010

SummaryThis report documents our experience with intravenous immune globulin (IVIG) (1 g/kg, iv) and high‐dose, anti‐D immune globulin (anti‐D) (75 μg/kg) as initial treatment for childhood immune thrombocytopenic purpura (ITP). The medical records of children diagnosed with ITP at a single institution between January 2003 and May 2008 were retrospectively reviewed. Participants received either IVIG or high‐dose anti‐D immune globulin as their initial treatment for ITP. For the 53 patients included for analysis, there was no statistical difference in efficacy between each group; however, patients who received anti‐D experienced a higher rate of adverse drug reactions (ADRs), particularly chills and rigours, and 2 of 24 patients in the anti‐D group developed severe anaemia requiring medical intervention. Patients who presented with mucosal bleeding had higher rates of treatment failure (32%) compared to those who presented with dry purpura (6%), regardless of treatment. Both IVIG and high‐dose anti‐D are effective first‐line therapies for childhood ITP. However, we observed increased ADRs in the high‐dose anti‐D group in contrast to previously published reports. Further studies are needed to evaluate safety and premedications for high‐dose anti‐D and to determine the utility of using the presence of mucosal bleeding to predict treatment failure.
Behaviour and attitudes among Spanish general dentists towards the anticoagulated patient: a pilot study
Authors: López‐Jornet Pia , Camacho‐Alonso Fabio , Escribano Myriam Gonzalez , Martinez‐Beneyto Yolanda 
Published: January 2010

AbstractAim  To determine the attitude of Spanish general dentists in relation to dental extraction in patients with heart valve prostheses subjected to acenocoumarol anticoagulation.Material and methods  A telephone survey was made of Spanish general dentists, asking about the indicated approach in the case of performing dental extractions in patients with heart valve prostheses subjected to acenocoumarol (Sintrom®) anticoagulation.Results  Of the 271 dentists answered, 175 were male (64.6%) and 96 were female (35.4%), with a mean professional experience of 20.17 ± 9.3 years. A total of 228 dentists (84.1%) indicated the need to refer the patient to a specialist for establishing the required approach, while 43 dentists (15.9%) did not consider such a measure to be necessary. Among this latter group of 43 dentists, 26 (60.5%) considered that acenocoumarol should be withdrawn or replaced by low‐molecular weight heparin, while 17 (39.5%) were of the opinion that the anticoagulation regimen should not be modified. In relation to the international normalized ratio, 36 (83.7%) did not consider it necessary to request this parameter. As regards the prevention of endocarditis, 11 (25.6%) specified the need for prophylaxis, although only eight (72.7%) did so correctly. There were no statistically significant differences in behaviour in relation to either gender or years of professional experience.Conclusions  This study identifies a lack of knowledge on the part of the dentists regarding the approach to dental extraction in patients with heart valve prostheses subjected to anticoagulation. Due educational measures therefore should be reinforced among these professionals.
Genetic analysis of petrobactin transport in Bacillus anthracis
Authors: Carlson Jr Paul E. , Dixon Shandee D. , Janes Brian K. , Carr Katherine A. , Nusca Tyler D. , Anderson Erica C. , Keene Sarra E. , Sherman David H. , Hanna Philip C. 
Published: January 2010

SummaryIron acquisition mechanisms play an important role in the pathogenesis of many infectious microbes. In Bacillus anthracis, the siderophore petrobactin is required for both growth in iron‐depleted conditions and for full virulence of the bacterium. Here we demonstrate the roles of two putative petrobactin binding proteins FatB and FpuA (encoded by GBAA5330 and GBAA4766 respectively) in B. anthracis iron acquisition and pathogenesis. Markerless deletion mutants were created using allelic exchange. The ΔfatB strain was capable of wild‐type levels of growth in iron‐depleted conditions, indicating that FatB does not play an essential role in petrobactin uptake. In contrast, ΔfpuA bacteria exhibited a significant decrease in growth under low‐iron conditions when compared with wild‐type bacteria. This mutant could not be rescued by the addition of exogenous purified petrobactin. Further examination of this strain demonstrated increased levels of petrobactin accumulation in the culture supernatants, suggesting no defect in siderophore synthesis or export but, instead, an inability of ΔfpuA to import this siderophore. ΔfpuA spores were also significantly attenuated in a murine model of inhalational anthrax. These results provide the first genetic evidence demonstrating the role of FpuA in petrobactin uptake.