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Chomphunuch Songsiriritthigul, Suwimon Suebka, Chun Jung Chen, Pitchayada Fuengfuloy, Pitak Chuawong
The N-terminal anticodon-binding domain of the nondiscriminating aspartyl-tRNA synthetase (ND-AspRS) plays a crucial role in the recognition of both tRNA(Asp) and tRNA(Asn). Here, the first X-ray crystal structure of the N-terminal domain of this enzyme (ND-AspRS1-104) from the human-pathogenic bacterium Helicobacter pylori is reported at 2.0 Å resolution. The apo form of H. pylori ND-AspRS1-104 shares high structural similarity with the N-terminal anticodon-binding domains of the discriminating aspartyl-tRNA synthetase (D-AspRS) from Escherichia coli and ND-AspRS from Pseudomonas aeruginosa, allowing recognition elements to be proposed for tRNA(Asp) and tRNA(Asn)...
February 1, 2017: Acta Crystallographica. Section F, Structural Biology Communications
Kamila K Myka, Michelle Hawkins, Aisha H Syeda, Milind K Gupta, Caroline Meharg, Mark S Dillingham, Nigel J Savery, Robert G Lloyd, Peter McGlynn
Conflicts between replication and transcription challenge chromosome duplication. Escherichia coli replisome movement along transcribed DNA is promoted by Rep and UvrD accessory helicases with Δrep ΔuvrD cells being inviable under rapid growth conditions. We have discovered that mutations in a tRNA gene, aspT, in an aminoacyl tRNA synthetase, AspRS, and in a translation factor needed for efficient proline-proline bond formation, EF-P, suppress Δrep ΔuvrD lethality. Thus replication-transcription conflicts can be alleviated by the partial sacrifice of a mechanism that reduces replicative barriers, namely translating ribosomes that reduce RNA polymerase backtracking...
December 11, 2016: Nucleic Acids Research
Lizzette M Gómez Ramos, Johanna M Smeekens, Nicholas A Kovacs, Jessica C Bowman, Roger M Wartell, Ronghu Wu, Loren Dean Williams
Divergence between prokaryotic and eukaryotic ribosomal RNA (rRNA) and among eukaryotic ribosomal RNAs is focused in expansion segments (ESs). Eukaryotic ribosomes are significantly larger than prokaryotic ribosomes partly because of their ESs. We hypothesize that larger rRNAs of complex organisms could confer increased functionality to the ribosome. Here, we characterize the binding partners of Saccharomyces cerevisiae expansion segment 7 (ES7), which is the largest and most variable ES of the eukaryotic large ribosomal subunit and is located at the surface of the ribosome...
October 9, 2016: Journal of Molecular Biology
Aleyamma Mathew, Preethi Sara George, Asha Arjunan, Paul Augustine, Mc Kalavathy, G Padmakumari, Beela Sarah Mathew
BACKGROUND: Increasing breast cancer (BC) incidence rates have been reported from India; causal factors for this increased incidence are not understood and diagnosis is mostly in advanced stages. Trivandrum exhibits the highest BC incidence rates in India. This study aimed to estimate trends in incidence by age from 2005- 2014, to predict rates through 2020 and to assess the stage at diagnosis of BC in Trivandrum. MATERIALS AND METHODS: BC cases were obtained from the Population Based Cancer Registry, Trivandrum...
2016: Asian Pacific Journal of Cancer Prevention: APJCP
Neil O'Gorman, David Wright, Daniel L Rolnik, Kypros H Nicolaides, Liona C Poon
INTRODUCTION: Pre-eclampsia (PE) affects 2-3% of all pregnancies and is a major cause of maternal and perinatal morbidity and mortality. Prophylactic use of low-dose aspirin in women at risk for PE may substantially reduce the prevalence of the disease. Effective screening for PE requiring delivery before 37 weeks (preterm PE) can be provided by a combination of maternal factors, uterine artery Doppler, mean arterial pressure, maternal serum pregnancy-associated plasma protein A and placental growth factor at 11-13 weeks' gestation, with a detection rate of 75% at a false-positive rate of 10%...
June 28, 2016: BMJ Open
Nilendra Nair, Hannah Raff, Mohammed Tarek Islam, Melanie Feen, Denise M Garofalo, Kelly Sheppard
Synthesis of asparaginyl-tRNA (Asn-tRNA(Asn)) in bacteria can be formed either by directly ligating Asn to tRNA(Asn) using an asparaginyl-tRNA synthetase (AsnRS) or by synthesizing Asn on the tRNA. In the latter two-step indirect pathway, a non-discriminating aspartyl-tRNA synthetase (ND-AspRS) attaches Asp to tRNA(Asn) and the amidotransferase GatCAB transamidates the Asp to Asn on the tRNA. GatCAB can be similarly used for Gln-tRNA(Gln) formation. Most bacteria are predicted to use only one route for Asn-tRNA(Asn) formation...
February 13, 2016: Journal of Molecular Biology
Kouji Uda, Keita Abe, Yoko Dehara, Kiriko Mizobata, Natsumi Sogawa, Yuki Akagi, Mai Saigan, Atanas D Radkov, Luke A Moe
Free D-amino acids have been found in various invertebrate phyla, while amino acid racemase genes have been identified in few species. The purpose of this study is to elucidate the distribution, function, and evolution of amino acid racemases in invertebrate animals. We searched the GenBank databases, and found 11 homologous serine racemase genes from eight species in eight different invertebrate phyla. The cloned genes were identified based on their maximum activity as Acropora millepora (Cnidaria) serine racemase (SerR) and aspartate racemase (AspR), Caenorhabditis elegans (Nematoda) SerR, Capitella teleta (Annelida) SerR, Crassostrea gigas (Mollusca) SerR and AspR, Dugesia japonica (Platyhelminthes) SerR, Milnesium tardigradum (Tardigrada) SerR, Penaeus monodon (Arthropoda) SerR and AspR and Strongylocentrotus purpuratus (Echinodermata) AspR...
February 2016: Amino Acids
Cheryl Hennig, C David L Thomas, John G Clement, David M L Cooper
The primary microstructural unit of cortical bone, the secondary osteon or Haversian system, is widely assumed to have a cylindrical shape. It is generally accepted that osteons are roughly circular in cross-section and deviations from circularity have been attributed to deviations from longitudinal orientation. To our knowledge this idealized geometric relationship, which assumes osteons are perfect cylinders, has not been rigorously explored. As such, we sought to explore two research questions: (i) Does the orientation of osteons in 3D explain variation in shapes visualized in 2D? (ii) Can differences in osteon 3D orientation explain previously reported age-related differences observed in their 2D cross-sectional shape (e...
October 2015: Journal of Anatomy
Erich M Schwarz, Yan Hu, Igor Antoshechkin, Melanie M Miller, Paul W Sternberg, Raffi V Aroian
Hookworms infect over 400 million people, stunting and impoverishing them. Sequencing hookworm genomes and finding which genes they express during infection should help in devising new drugs or vaccines against hookworms. Unlike other hookworms, Ancylostoma ceylanicum infects both humans and other mammals, providing a laboratory model for hookworm disease. We determined an A. ceylanicum genome sequence of 313 Mb, with transcriptomic data throughout infection showing expression of 30,738 genes. Approximately 900 genes were upregulated during early infection in vivo, including ASPRs, a cryptic subfamily of activation-associated secreted proteins (ASPs)...
April 2015: Nature Genetics
Sara Harris Smith, Kelly J Bennett, Alicia A Livinski
BACKGROUND: Twitter has emerged as a critical source of free and openly available information during emergency response operations, providing an unmatched level of on-the-ground situational awareness in real-time. Responders and survivors turn to Twitter to share information and resources within communities, conduct rumor control, and provide a "boots on the ground" understanding of the disaster. However, the ability to tune out background "noise" is essential to effectively utilizing Twitter to identify important and useful information during an emergency response...
2014: PLoS Currents
Tateki Suzuki, Akiyoshi Nakamura, Koji Kato, Dieter Söll, Isao Tanaka, Kelly Sheppard, Min Yao
Many prokaryotes lack a tRNA synthetase to attach asparagine to its cognate tRNA(Asn), and instead synthesize asparagine from tRNA(Asn)-bound aspartate. This conversion involves two enzymes: a nondiscriminating aspartyl-tRNA synthetase (ND-AspRS) that forms Asp-tRNA(Asn), and a heterotrimeric amidotransferase GatCAB that amidates Asp-tRNA(Asn) to form Asn-tRNA(Asn) for use in protein synthesis. ND-AspRS, GatCAB, and tRNA(Asn) may assemble in an ∼400-kDa complex, known as the Asn-transamidosome, which couples the two steps of asparagine biosynthesis in space and time to yield Asn-tRNA(Asn)...
January 13, 2015: Proceedings of the National Academy of Sciences of the United States of America
Tateki Suzuki, Keitaro Yamashita, Yoshikazu Tanaka, Isao Tanaka, Min Yao
Most canonical aminoacyl-tRNAs are synthesized directly by their cognate aminoacyl-tRNA synthetases (aaRSs), but glutaminyl-tRNA(Gln) and asparaginyl-tRNA(Asn) are synthesized indirectly by two-step processes. These processes are catalyzed by the transamidosome, a large ribonucleoprotein particle composed of GatA, GatB, GatC, aaRS and tRNA. In this study, the Asn-transamidosome from Pseudomonas aeruginosa was reconstructed and crystallized by mixing purified GatCAB complex, AspRS and tRNA(Asn). The crystal of the Asn-transamidosome belonged to space group P2₁, with unit-cell parameters a=93...
June 2014: Acta Crystallographica. Section F, Structural Biology Communications
Stefani R Mladenova, Kathryn R Stein, Lianne Bartlett, Kelly Sheppard
The human pathogen Staphylococcus aureus is an asparagine prototroph despite its genome not encoding an asparagine synthetase. S. aureus does use an asparaginyl-tRNA synthetase (AsnRS) to directly ligate asparagine to tRNA(Asn). The S. aureus genome also codes for one aspartyl-tRNA synthetase (AspRS). Here we demonstrate the lone S. aureus aspartyl-tRNA synthetase has relaxed tRNA specificity and can be used with the amidotransferase GatCAB to synthesize asparagine on tRNA(Asn). S. aureus thus encodes both the direct and indirect routes for Asn-tRNA(Asn) formation while encoding only one aspartyl-tRNA synthetase...
May 2, 2014: FEBS Letters
Tatjana Ramich, Beate Schacher, Susanne Scharf, Lasse Röllke, Rita Arndt, Peter Eickholz, Katrin Nickles
AIM: This study aimed to make a comparison of two sampling strategies of subgingival plaque after combined mechanical-antibiotic periodontal therapy. METHODS: Thirty patients (18 female) suffering from aggressive (n = 12) or generalised severe chronic (n = 18) periodontitis were included. Aggregatibacter actinomycetemcomitans had been detected subgingivally in all prior to anti-infective therapy (AT) and combined mechanical-antibiotic AT had been rendered...
January 2015: Clinical Oral Investigations
Kannipa Tasanapak, Uraiwan Masud-Tippayasak, Kazunobu Matsushita, Wichien Yongmanitchai, Gunjana Theeragool
The aspS gene encoding Aspartyl-tRNA synthetase (AspRS) from a thermotolerant acetic acid bacterium, Acetobacter pasteurianus SKU1108, has been cloned and characterized. The open reading frame (ORF) of the aspS gene consists of 1,788 bp, encoding 595 amino acid residues. The highly conserved Gly-Val-Asp-Arg ATP binding motif (motif 3) is located at the position 537-540 in the C-terminus. Deletion analysis of the aspS gene upstream region suggested that the promoter is around 173 bp upstream from the ATG initiation codon...
December 2013: Journal of Microbiology / the Microbiological Society of Korea
Steven L Simon, C Norman Coleman, Michael A Noska, Thomas Bowman
Following the earthquake and tsunami in northern Japan on 11 March 2011, and the ensuing damage to the Fukushima Daiichi nuclear power plant complex, a request by the U.S. Ambassador to Japan to the U.S. Department of Health and Human Services (DHHS) Assistant Secretary for Preparedness and Response (ASPR) resulted in deployment of a five-person team of subject matter experts to the U.S. Embassy. The primary purpose of the deployment was to provide the U.S. Embassy in Tokyo with guidance on health and medical issues related to potential radiation exposure of U...
May 2012: Health Physics
D Goulian
Since the inception of the recently concluded formal study, liquid injectable silicone has been both used and abused by many. Reports in both lay and professional literature reflect this experience in the form of a wide range of opinions and judgments regarding the use of this material in corrective surgery. Those intimately involved in the former study agree that, used properly, liquid injectable silicone appears to have redeeming value in at least a limited group of problem situations. These investigators further agree that its general use could lead to many problems unless its limited scope of usefulness and proper use are known, accepted, and abided by those using it...
December 1978: Aesthetic Plastic Surgery
Hagen Schwenzer, Gert C Scheper, Nathalie Zorn, Luc Moulinier, Agnès Gaudry, Emmanuelle Leize, Franck Martin, Catherine Florentz, Olivier Poch, Marie Sissler
Mammalian mitochondrial aminoacyl-tRNA synthetases are nuclear-encoded enzymes that are essential for mitochondrial protein synthesis. Due to an endosymbiotic origin of the mitochondria, many of them share structural domains with homologous bacterial enzymes of same specificity. This is also the case for human mitochondrial aspartyl-tRNA synthetase (AspRS) that shares the so-called bacterial insertion domain with bacterial homologs. The function of this domain in the mitochondrial proteins is unclear. Here, we show by bioinformatic analyses that the sequences coding for the bacterial insertion domain are less conserved in opisthokont and protist than in bacteria and viridiplantae...
May 2014: Biochimie
Min Guo, Xiang-Lei Yang
When compared to other conserved housekeeping protein families, such as ribosomal proteins, during the evolution of higher eukaryotes, aminoacyl-tRNA synthetases (aaRSs) show an apparent high propensity to add new sequences, and especially new domains. The stepwise emergence of those new domains is consistent with their involvement in a broad range of biological functions beyond protein synthesis, and correlates with the increasing biological complexity of higher organisms. These new domains have been extensively characterized based on their evolutionary origins and their sequence, structural, and functional features...
2014: Topics in Current Chemistry
Pitchayada Fuengfuloy, Pitak Chuawong, Suwimon Suebka, Pakorn Wattana-Amorn, Christopher Williams, Matthew P Crump, Chomphunuch Songsiriritthigul
Aminoacyl-tRNA synthetases (aaRSs) covalently attach an amino acid to its cognate tRNA isoacceptors through an ester bond. The standard set of 20 amino acids implies 20 aaRSs for each pair of amino acid/tRNA isoacceptors. However, the genomes of all archaea and some bacteria do not encode for a complete set of 20 aaRSs. For the human pathogenic bacterium Helicobacter pylori, a gene encoding asparaginyl-tRNA synthetase (AsnRS) is absent whilst an aspartyl-tRNA synthetase (AspRS) aminoacylates both tRNA(Asp) and tRNA(Asn) with aspartate...
May 2013: Protein Expression and Purification
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