Solving Common Algorithmic Problem by Recognizer Tissue P Systems

Common Algorithmic Problem is an optimization problem, which has the nice property that several other NP-complete problems can be reduced to it in linear time. In this work, we deal with its decision version in the framework of tissue P systems. A tissue P system with cell division is a computing model which has two types of rules: communication and division rules. The ability of cell division allows us to obtain an exponential amount of cells in linear time and to design cellular solutions to computationally hard problems in polynomial time. We here present an effective solution to Common Algorithmic Decision Problem by using a family of recognizer tissue P systems with cell division. Furthermore, a formal verification of this solution is given.Ministerio de Ciencia e Innovación TIN2009–13192Junta de Andalucía P08-TIC-0420

A Uniform Solution to Common Algorithmic Problem by Tissue P Systems with Cell Division

Common algorithmic problem is an optimization problem, which has the nice property that several other NP-complete problems can be reduced to it in linear time. A tissue P system with cell division is a computing model which has two basic characters: intercellular communication and the ability of cell division. The ability of cell division allows us to obtain an exponential amount of cells in linear time and to design cellular solutions to computationally hard problems in polynomial time. We here present an effective solution to the common algorithmic decision problem using a family of recognizer tissue P systems with cell division.Ministerio de Ciencia e Innovación TIN2009-13192Junta de Andalucía P08-TIC0420

A double salt of iodo­bis­muthate: cis-aqua­iodidobis(1,10-phenanthroline)cobalt(II) tris­(1,10-phenanthroline)cobalt(II) trans-hexa-μ2-iodido-hexa­iodidotribismuthate(III)

In the title complex, [Co(C12H8N2)3][CoI(C12H8N2)2(H2O)][Bi3I12], conventionally abbreviated [Co(phen)3][CoI(phen)2(H2O)][Bi3I12], where phen is 1,10-phenanthroline, the CoII atom in one cation is coordinated by six N atoms from three phen ligands in an octa­hedral coordination while the CoII atom in the other cation is coordinated octa­hedrally by four N atoms from two phen ligands, one water O atom and one I atom. In the anion, three BiIII ions adopt an octa­hedral coordination constructed by six I− ligands. The three BiI6 octa­hedra are fused together through trans face-sharing

Linear Time Solution to Prime Factorization by Tissue P Systems with Cell Division

Prime factorization is useful and crucial for public-key cryptography, and its application in public-key cryptography is possible only because prime factorization has been presumed to be difficult. A polynomial-time algorithm for prime factorization on a quantum computer is given by P. W. Shor in 1997. In this work, a linear-time solution for prime factorization is given on a kind of biochemical computational devices - tissue P systems with cell division, instead of physical computational devices.Ministerio de Ciencia e Innovación TIN2009-13192Junta de Andalucía P08-TIC0420

Running Cells with Decision-Making Mechanism: Intelligence Decision P System for Evacuation Simulation

Cell migration is a central process which happens along with multicellular organisms' development and maintenance. The process that cells move to specidic locations in particular directions has some similarities with pedestrian walking behaviour. In this work, we propose a simulation model called an Intelligence Decision P System (IDPS), which is inspired by the process of cell migration. Each cell has its own decision-making mechanism and moving mechanism. They move towards its goals on a two-dimensional space under the guidance of external signals and its own regulations. Cells also communicate with each other according to specidic interaction mechanism. The environment is dedined as a place for cell movement. It includes signal objects, some of which help start or end the migration and others have great influence on the speed and directions of cells. It also keeps a record of current position for each cell. Comparing with traditional P systems, cells can be considered as intelligent particles with decision-making mechanism and they can move to their destination. A case study is about modeling and simulating a building evacuation problem in a dire emergency by using the IDPS model. To our best knowledge, the topic of evacuation simulation was not under study in the dield of membrane computing before. The simulation result shows that the IDPS allows much easier and more precise modelling of pedestrian evacuation problems. So it is supposed to be a good simulation model for pedestrian walking behaviour

Analysis of the transcriptome of Panax notoginseng root uncovers putative triterpene saponin-biosynthetic genes and genetic markers

<p>Abstract</p> <p>Background</p> <p><it>Panax notoginseng </it>(Burk) F.H. Chen is important medicinal plant of the <it>Araliacease </it>family. Triterpene saponins are the bioactive constituents in <it>P. notoginseng</it>. However, available genomic information regarding this plant is limited. Moreover, details of triterpene saponin biosynthesis in the <it>Panax </it>species are largely unknown.</p> <p>Results</p> <p>Using the 454 pyrosequencing technology, a one-quarter GS FLX titanium run resulted in 188,185 reads with an average length of 410 bases for <it>P. notoginseng </it>root. These reads were processed and assembled by 454 GS <it>De Novo </it>Assembler software into 30,852 unique sequences. A total of 70.2% of unique sequences were annotated by Basic Local Alignment Search Tool (BLAST) similarity searches against public sequence databases. The Kyoto Encyclopedia of Genes and Genomes (KEGG) assignment discovered 41 unique sequences representing 11 genes involved in triterpene saponin backbone biosynthesis in the 454-EST dataset. In particular, the transcript encoding dammarenediol synthase (DS), which is the first committed enzyme in the biosynthetic pathway of major triterpene saponins, is highly expressed in the root of four-year-old <it>P. notoginseng</it>. It is worth emphasizing that the candidate cytochrome P450 (Pn02132 and Pn00158) and UDP-glycosyltransferase (Pn00082) gene most likely to be involved in hydroxylation or glycosylation of aglycones for triterpene saponin biosynthesis were discovered from 174 cytochrome P450s and 242 glycosyltransferases by phylogenetic analysis, respectively. Putative transcription factors were detected in 906 unique sequences, including Myb, homeobox, WRKY, basic helix-loop-helix (bHLH), and other family proteins. Additionally, a total of 2,772 simple sequence repeat (SSR) were identified from 2,361 unique sequences, of which, di-nucleotide motifs were the most abundant motif.</p> <p>Conclusion</p> <p>This study is the first to present a large-scale EST dataset for <it>P. notoginseng </it>root acquired by next-generation sequencing (NGS) technology. The candidate genes involved in triterpene saponin biosynthesis, including the putative CYP450s and UGTs, were obtained in this study. Additionally, the identification of SSRs provided plenty of genetic makers for molecular breeding and genetics applications in this species. These data will provide information on gene discovery, transcriptional regulation and marker-assisted selection for <it>P. notoginseng</it>. The dataset establishes an important foundation for the study with the purpose of ensuring adequate drug resources for this species.</p

Extensive pyrosequencing reveals frequent intra-genomic variations of internal transcribed spacer regions of nuclear ribosomal DNA

BACKGROUND: Internal transcribed spacer of nuclear ribosomal DNA (nrDNA) is already one of the most popular phylogenetic and DNA barcoding markers. However, the existence of its multiple copies has complicated such usage and a detailed characterization of intra-genomic variations is critical to address such concerns. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we used sequence-tagged pyrosequencing and genome-wide analyses to characterize intra-genomic variations of internal transcribed spacer 2 (ITS2)regions from 178 plant species. We discovered that mutation of ITS2 is frequent, with a mean of 35 variants per species. And on average, three of the most abundant variants make up 91% of all ITS2 copies. Moreover, we found different congeneric species share identical variants in 13 genera. Interestingly, different species across different genera also share identical variants. In particular, one minor variant of ITS2 in Eleutherococcus giraldii was found identical to the ITS2 major variant of Panax ginseng, both from Araliaceae family. In addition, DNA barcoding gap analysis showed that the intra-genomic distances were markedly smaller than those of the intra-specific or inter-specific variants. When each of 5543 variants were examined for its species discrimination efficiency, a 97% success rate was obtained at the species level. CONCLUSIONS: Identification of identical ITS2 variants across intra-generic or inter-generic species revealed complex species evolutionary history, possibly, horizontal gene transfer and ancestral hybridization. Although intra-genomic multiple variants are frequently found within each genome, the usage of the major variants alone is sufficient for phylogeny construction and species determination in most cases. Furthermore, the inclusion of minor variants further improves the resolution of species identification.Jingyuan Song, Linchun Shi, Dezhu Li, Yongzhen Sun, Yunyun Niu, Zhiduan Chen, Hongmei Luo, Xiaohui Pang, Zhiying Sun, Chang Liu, Aiping Lv, Youping Deng, Zachary Larson-Rabin, Mike Wilkinson and Shilin Che

Irradiated Esophageal Cells are Protected from Radiation-Induced Recombination by MnSOD Gene Therapy

Radiation-induced DNA damage is a precursor to mutagenesis and cytotoxicity. During radiotherapy, exposure of healthy tissues can lead to severe side effects. We explored the potential of mitochondrial SOD (MnSOD) gene therapy to protect esophageal, pancreatic and bone marrow cells from radiation-induced genomic instability. Specifically, we measured the frequency of homologous recombination (HR) at an integrated transgene in the Fluorescent Yellow Direct Repeat (FYDR) mice, in which an HR event can give rise to a fluorescent signal. Mitochondrial SOD plasmid/liposome complex (MnSOD-PL) was administered to esophageal cells 24 h prior to 29 Gy upper-body irradiation. Single cell suspensions from FYDR, positive control FYDR-REC, and negative control C57BL/6NHsd (wild-type) mouse esophagus, pancreas and bone marrow were evaluated by flow cytometry. Radiation induced a statistically significant increase in HR 7 days after irradiation compared to unirradiated FYDR mice. MnSOD-PL significantly reduced the induction of HR by radiation at day 7 and also reduced the level of HR in the pancreas. Irradiation of the femur and tibial marrow with 8 Gy also induced a significant increase in HR at 7 days. Radioprotection by intraesophageal administration of MnSOD-PL was correlated with a reduced level of radiation-induced HR in esophageal cells. These results demonstrate the efficacy of MnSOD-PL for suppressing radiation-induced HR in vivo.National Institutes of Health (U.S.) (NIH Grant R01-CA83876-8)National Institute of Allergy and Infectious Diseases (U.S.) (NIH grant U19A1068021)National Institutes of Health (U.S.) (Grant T32-ES07020)United States. Dept. of Energy (DOE DE-FG01-04ER04)National Institutes of Health (U.S.) (NIH P01-CA26735

Pyrosequencing of the Camptotheca acuminata transcriptome reveals putative genes involved in camptothecin biosynthesis and transport

Background: Camptotheca acuminata is a Nyssaceae plant, often called the "happy tree", which is indigenous in Southern China. C. acuminata produces the terpenoid indole alkaloid, camptothecin (CPT), which exhibits clinical effects in various cancer treatments. Despite its importance, little is known about the transcriptome of C. acuminata and the mechanism of CPT biosynthesis, as only few nucleotide sequences are included in the GenBank database.Results: From a constructed cDNA library of young C. acuminata leaves, a total of 30,358 unigenes, with an average length of 403 bp, were obtained after assembly of 74,858 high quality reads using GS De Novo assembler software. Through functional annotation, a total of 21,213 unigenes were annotated at least once against the NCBI nucleotide (Nt), non-redundant protein (Nr), Uniprot/SwissProt, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Arabidopsis thaliana proteome (TAIR) databases. Further analysis identified 521 ESTs representing 20 enzyme genes that are involved in the backbone of the CPT biosynthetic pathway in the library. Three putative genes in the upstream pathway, including genes for geraniol-10-hydroxylase (CaPG10H), secologanin synthase (CaPSCS), and strictosidine synthase (CaPSTR) were cloned and analyzed. The expression level of the three genes was also detected using qRT-PCR in C. acuminata. With respect to the branch pathway of CPT synthesis, six cytochrome P450s transcripts were selected as candidate transcripts by detection of transcript expression in different tissues using qRT-PCR. In addition, one glucosidase gene was identified that might participate in CPT biosynthesis. For CPT transport, three of 21 transcripts for multidrug resistance protein (MDR) transporters were also screened from the dataset by their annotation result and gene expression analysis.Conclusion: This study produced a large amount of transcriptome data from C. acuminata by 454 pyrosequencing. According to EST annotation, catalytic features prediction, and expression analysis, novel putative transcripts involved in CPT biosynthesis and transport were discovered in C. acuminata. This study will facilitate further identification of key enzymes and transporter genes in C. acuminata