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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Preconditioning with L-alanyl-glutamine, L-arginine and ω-3, ω-6 and ω-9 fatty acids on heat shock proteins and inflammatory mediators in patients submitted to total abdominoplasty / PrÃ-condicionamento com L-alanil-glutamina, L-arginina e Ãmegas 3, 6 e 9 sobre as proteÃnas de choque tÃrmico e marcadores inflamatÃrios em pacientes submetidas à abdominoplastia total

Mara Cinthia Coelho Cavalcante 24 July 2014 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Abdominoplasty is a lower abdominal lipectomy combined with muscle fascia repair by plication of the aponeuroses of the rectus abdominis muscle. The procedure is traumatic and associated with stress-related inflammation. Preoperative administration of nutraceuticals is believed to reduce postoperative complications such as inflammation and improve surgical results. Once a day for 7 days prior to surgery, patients were supplemented with two diets: SNO1 (negative control) or SNO2. The former was a dairy drink containing 0% fat, 64% carbohydrate (100% maltodextrin) and 36% protein (100% calcium caseinate), corresponding to 37.4 kcal/100mL. The latter was a dairy drink containing 14% carbohydrate (25% maltodextrin, 75% fructose), 25% protein (60% L-alanyl-glutamine, 40% L-arginine) and 61% lipids in the form of a mixture of oleic acid-rich sunflower oil, canola oil, fish oil and medium-chain triglycerides containing ω-9, ω-6 and ω-3 fatty acids, the latter with α-linolenic acid, eicosapetaenoic acid and docosahexaenoic acid, with a ω-9/ω-6 ratio of 3.2:1 (antioxidant action) and a ω-6/ω-3 ratio of 1.4:1 (anti-inflammatory action), corresponding to 200 kcal/100mL. Each patient ingested 200mL SNO1 or SNO2 blended with 50 g diet ice-cream. The sample consisted of 25 adult patients randomly assigned to SNO1 (n=11) or SNO2 (n=14) and submitted to total abdominoplasty. The study variables included HSP-27, HSP-70, IL-1β, IL-6, PCR and TNF-α. Clinical and lab tests were performed on four occasions: T0=on the 1st day of supplementation following a 12-hour fast; T1=on the 8th day, upon induction of anesthesia, after confirming ingestion of study diet for 7 consecutive days; T2=on the 9th day (POD 1), 24 hours after surgery; and T3=on the 11th day (POD 3), 72 hours after surgery. No significant difference was observed between the groups at any of the four moments in time. In conclusion, oral nutraceutical supplementation with L-alanyl-glutamine, arginine and mixtures of oils with high ω-9/ω-6 ratio and low ω-6/ω-3 ratio has no significant preconditioning effect on inflammatory mediators in surgical trauma / A abdominoplastia consiste de lipectomia abdominal baixa, associada à reparaÃÃo ou âplÃsticaâ mÃsculo-fascial, atravÃs da plicatura das aponeuroses dos mÃsculos retos abdominais. Caracteriza-se como um trauma cirÃrgico, promovendo uma inflamaÃÃo inserida no conceito mais amplo de âresposta ao estresseâ. A nutriÃÃo prÃ-operatÃria pode minimizar as complicaÃÃes pÃs-operatÃrias e melhorar os resultados cirÃrgicos. No presente estudo foi ofertada uma vez ao dia Ãs pacientes suplementaÃÃo oral 1 (SNO1) ou suplementaÃÃo oral 2 (SNO2), no perÃodo prÃ-operatÃrio, durantes 7 dias. A SNO1 à considerada como controle negativo, constitui uma bebida lÃctea com 0% de gordura, composta por 64% de carboidrato (100% maltodextrina) e 36% de proteÃna (100% caseinato de cÃlcio) com calorias totais igual a 37,4kcal/100ml. A SNO2 considerada como o grupo teste foi composta por 14% de carboidrato (25% maltodextrina e 75% frutose), 25% de proteÃna (60%L-alanil-glutamina e 40%L-arginina) e 61% de lipÃdios (mistura de Ãleos de girassol de alto teor olÃico, canola, peixe e triglicerÃdeo de cadeia mÃdia (TCM) contendo Ãmega-9 (ω9), Ãmega-6 (ω6) e Ãmega-3 (ω3), deste Ãltimo na forma de Ãcido α-linolÃnico ALA, Ãcido eicosapetaenÃico EPA e Ãcido docosahexaenÃico DHA com relaÃÃes ω-9/ω-6 de 3,2:1 e ω-6/ω-3 de 1,4:1, com calorias totais de 200kcal/100ml. Cada paciente ingeriu 200 ml de SNO1 ou SNO2, misturado a 50 gramas de sorvete diet. Foram selecionadas e acompanhadas um grupo de 25 pacientes adultas submetidas à abdominoplastia total que foram agrupadas, aleatoriamente, nos grupos SNO1 (N=11) e SNO2 (N=14). As variÃveis avaliadas foram: HSP-27, HSP-70, IL-1β, IL-6, PCR e TNF-α. As avaliaÃÃes clÃnicas e laboratoriais foram realizadas em quatro momentos: no prÃ-cirÃrgico 1 dia (T0) de inÃcio da suplementaÃÃo, com as pacientes em jejum por 12 horas; no 8 dia (T1) na induÃÃo anestÃsica da cirurgia, apÃs confirmar que a paciente ingeriu por sete dias seguidos a suplementaÃÃo; no 9 dia ou 1 PO (T2), 24h apÃs o procedimento de abdominoplastia total; e no 11 dia ou 3 PO (T3), 72h apÃs a cirurgia. NÃo foram evidenciadas diferenÃas estatisticamente significantes entre os grupos e os tempos. Portanto, a suplementaÃÃo nutricional oral utilizando l-alanil-glutamina, arginina e misturas de Ãleos com elevada relaÃÃo ω-9/ ω-6 e baixa relaÃÃo ω-6/ω-3 contendo os Ãcidos ω-3 ALA, EPA e DHA, nÃo possui efeito prÃ-condicionante nutracÃutico sobre proteÃnas de choque e nos mediadores inflamatÃrios aqui estudados no trauma cirÃrgico.
92

Arginina na fisiologia e produtividade do tomateiro cultivado em ambiente protegido / Arginine on the physiology and productivity of tomato cultivated in a protected environment

Vivyan Justi Conceição 30 May 2018 (has links)
O tomateiro (Solanum lycopersicum L.) é uma dicotiledônea pertencente à família Solanaceae e devido a sua amplitude de cultivo, essa hortaliça é considerada cosmopolita, sendo a segunda maior cultura mundial, depois da batata. A utilização de aminoácidos na agricultura tem sido realizada por décadas e através de vários estudos muitos benefícios têm sido reportados tais como o aumento de produtividade e atenuação de estresses hídricos e de temperatura. Existem ainda trabalhos que utilizam a aplicação de aminoácidos como forma de ativar certas rotas do metabolismo das plantas.Várias hipóteses são atribuídas aos efeitos dos aminoácidos nas plantas. As principais funções dos aminoácidos seriam: síntese de proteínas, formação de compostos intermediários dos hormônios vegetais e endógenos e efeito complexante em nutrientes.O presente trabalho teve o objetivo de avaliar o efeito da aplicação de arginina na fotossíntese, produtividade e qualidade do tomate híbrido \'Pizzadoro\', em ambiente de cultivo protegido.O delineamento experimental foi em blocos ao acaso, composto por 3 blocos e 6 tratamentos: controle; 0,10; 0,25; 0,50; 1,0 e 2,0 gL-1. As variáveis avaliadas foram divididas em 3 grupos: As atividades de enzimas antioxidantes (superóxido dismutase, ascorbato peroxidase e catalase), a peroxidação de lipídios, a produção de peróxido de hidrogênio; as variáveis fotossintéticas: fotossíntese líquida, concentração de CO2 interno, condutância estomática e transpiração; variáveis de produtividade: número de frutos separados em pequenos, médios e grandes, número de frutos não-comerciais e números de frutos com defeitos e número total de frutos; produtividade dos frutos pequenos, médios e grandes, não-comercial e com defeitos, além de produtividade comercial e produtividade total. Foram avaliadas ainda variáveis qualitativas:quantidade de ácido-ascórbico, teor de sólidos solúveis (SST), pH da polpa, acidez total titulável (ATT) e relação SST/ATT. Observou-se ativação dos mecanismos de defesa do tomateiro, pelo aumento dos níveis das enzimas antioxidantes APX e CAT. Houve aumento da fotossíntese, aumento da concentração interna de CO2, aumento da condutância estomática e aumento da transpiração com a aplicação das diferentes doses de arginina. A produtividade total do fruto foi influenciada pela aplicação da arginina. Não houve na qualidade, pelo teste de médias, influência resultante da aplicação da arginina. Para avaliar a melhor dosagem foi calculado o índice de correlação de posto. / The tomato (Solanum lycopersicum L.) is a dicotyledone belonging to the family Solanaceae and due to its amplitude of cultivation, this vegetable is considered cosmopolitan, being the second largest world culture after the potato. The use of amino acids in agriculture has been carried out for decades and through several studies many benefits have been reported such as increased productivity and attenuation of water stresses and temperature. There are also works that use the application of amino acids as a way to activate certain routes of plant metabolism. Several hypotheses are attributed to the effects of amino acids in plants. The main functions of amino acids would be: protein synthesis, formation of intermediate compounds of plant hormones and endogenous and complexing effect in nutrients. The present work had the objective of evaluating the effect of arginine application on the photosynthesis, productivity and quality of hybrid tomato \' Pizzadoro \'in a protected cultivation environment. The experimental design was in randomized blocks, composed of 3 blocks and 6 treatments: control; 0.10; 0.25; 0.50; 1.0 and 2.0 gL-1.The variables evaluated were divided into three groups: The activities of antioxidant enzymes (superoxide dismutase, ascorbate peroxidase and catalase), lipid peroxidation, hydrogen peroxide production; the photosynthetic variables: liquid photosynthesis, internal CO2 concentration, stomatal conductance and transpiration; productivity variables: number of separate fruits in small, medium and large, number of non-commercial fruits and numbers of fruits with defects and total number of fruits; productivity of small, medium and large fruits, non-commercial and defective, as well as commercial productivity and total productivity. It was also evaluated qualitative variables: amount of acid-ascorbic, soluble solids content (SST), pulp pH, total titratable acidity (ATT) and SST / ATT ratio. Activation of the tomato defense mechanisms was observed, by the increase of the antioxidant enzymes APX and CAT. There was an increase in photosynthesis, an increase in the internal concentration of CO2, an increase in stomatal conductance and an increase in transpiration with the application of different doses of arginine. The total productivity of the fruit was influenced by the application of arginine. There was no influence on the quality, by the means test, resulting from the application of arginine. To evaluate the best dosage, the rank correlation index was calculated.
93

Arginina na fisiologia e produtividade do tomateiro cultivado em ambiente protegido / Arginine on the physiology and productivity of tomato cultivated in a protected environment

Conceição, Vivyan Justi 30 May 2018 (has links)
O tomateiro (Solanum lycopersicum L.) é uma dicotiledônea pertencente à família Solanaceae e devido a sua amplitude de cultivo, essa hortaliça é considerada cosmopolita, sendo a segunda maior cultura mundial, depois da batata. A utilização de aminoácidos na agricultura tem sido realizada por décadas e através de vários estudos muitos benefícios têm sido reportados tais como o aumento de produtividade e atenuação de estresses hídricos e de temperatura. Existem ainda trabalhos que utilizam a aplicação de aminoácidos como forma de ativar certas rotas do metabolismo das plantas.Várias hipóteses são atribuídas aos efeitos dos aminoácidos nas plantas. As principais funções dos aminoácidos seriam: síntese de proteínas, formação de compostos intermediários dos hormônios vegetais e endógenos e efeito complexante em nutrientes.O presente trabalho teve o objetivo de avaliar o efeito da aplicação de arginina na fotossíntese, produtividade e qualidade do tomate híbrido \'Pizzadoro\', em ambiente de cultivo protegido.O delineamento experimental foi em blocos ao acaso, composto por 3 blocos e 6 tratamentos: controle; 0,10; 0,25; 0,50; 1,0 e 2,0 gL-1. As variáveis avaliadas foram divididas em 3 grupos: As atividades de enzimas antioxidantes (superóxido dismutase, ascorbato peroxidase e catalase), a peroxidação de lipídios, a produção de peróxido de hidrogênio; as variáveis fotossintéticas: fotossíntese líquida, concentração de CO2 interno, condutância estomática e transpiração; variáveis de produtividade: número de frutos separados em pequenos, médios e grandes, número de frutos não-comerciais e números de frutos com defeitos e número total de frutos; produtividade dos frutos pequenos, médios e grandes, não-comercial e com defeitos, além de produtividade comercial e produtividade total. Foram avaliadas ainda variáveis qualitativas:quantidade de ácido-ascórbico, teor de sólidos solúveis (SST), pH da polpa, acidez total titulável (ATT) e relação SST/ATT. Observou-se ativação dos mecanismos de defesa do tomateiro, pelo aumento dos níveis das enzimas antioxidantes APX e CAT. Houve aumento da fotossíntese, aumento da concentração interna de CO2, aumento da condutância estomática e aumento da transpiração com a aplicação das diferentes doses de arginina. A produtividade total do fruto foi influenciada pela aplicação da arginina. Não houve na qualidade, pelo teste de médias, influência resultante da aplicação da arginina. Para avaliar a melhor dosagem foi calculado o índice de correlação de posto. / The tomato (Solanum lycopersicum L.) is a dicotyledone belonging to the family Solanaceae and due to its amplitude of cultivation, this vegetable is considered cosmopolitan, being the second largest world culture after the potato. The use of amino acids in agriculture has been carried out for decades and through several studies many benefits have been reported such as increased productivity and attenuation of water stresses and temperature. There are also works that use the application of amino acids as a way to activate certain routes of plant metabolism. Several hypotheses are attributed to the effects of amino acids in plants. The main functions of amino acids would be: protein synthesis, formation of intermediate compounds of plant hormones and endogenous and complexing effect in nutrients. The present work had the objective of evaluating the effect of arginine application on the photosynthesis, productivity and quality of hybrid tomato \' Pizzadoro \'in a protected cultivation environment. The experimental design was in randomized blocks, composed of 3 blocks and 6 treatments: control; 0.10; 0.25; 0.50; 1.0 and 2.0 gL-1.The variables evaluated were divided into three groups: The activities of antioxidant enzymes (superoxide dismutase, ascorbate peroxidase and catalase), lipid peroxidation, hydrogen peroxide production; the photosynthetic variables: liquid photosynthesis, internal CO2 concentration, stomatal conductance and transpiration; productivity variables: number of separate fruits in small, medium and large, number of non-commercial fruits and numbers of fruits with defects and total number of fruits; productivity of small, medium and large fruits, non-commercial and defective, as well as commercial productivity and total productivity. It was also evaluated qualitative variables: amount of acid-ascorbic, soluble solids content (SST), pulp pH, total titratable acidity (ATT) and SST / ATT ratio. Activation of the tomato defense mechanisms was observed, by the increase of the antioxidant enzymes APX and CAT. There was an increase in photosynthesis, an increase in the internal concentration of CO2, an increase in stomatal conductance and an increase in transpiration with the application of different doses of arginine. The total productivity of the fruit was influenced by the application of arginine. There was no influence on the quality, by the means test, resulting from the application of arginine. To evaluate the best dosage, the rank correlation index was calculated.
94

An antisense approach to study the roles of arginine decarboxylase and putrescine N-methyltransferase in alkaloid metabolism in Nicotiana tabacum L

Chintapakorn, Yupynn, 1960- January 2002 (has links)
Abstract not available
95

The transdermal delivery of arginine vasopressin with pheroid technology / H. Coetzee

Coetzee, Hanneri January 2007 (has links)
Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2007.
96

Arginine and fetal growth in ovine models of intrauterine growth restriction

Lassala, Arantzatzu Leticia 15 May 2009 (has links)
This research was conducted to test the hypothesis that parenteralarginine supplementation is effective in enhancing birth weights of intrauterinegrowth restricted (IUGR) fetuses. Underfed and prolific ewes were used asexperimental models. The first study characterized the pharmacokinetics ofarginine and citrulline and assessed the potential of citrulline to serve as aprecursor for enhancing arginine availability in fetal and maternal plasma. Sixlate pregnant ewes and their fetuses were instrumented to access arterial andvenous circulations. Intravenous boluses of 155 mol of L-arginine-HCl or Lcitrullineper kg body weight were administered to each ewe. Administration ofcitrulline was more effective than arginine in achieving a sustained increase inconcentrations of arginine in maternal and fetal blood. Accordingly, theclearance rate of citrulline was lower and its biological half-life in maternal bloodgreater, when compared with arginine. The second experiment determined ifadministration of arginine to underfed ewes is effective in ameliorating orpreventing IUGR. Ewes were fed either 100% or 50% of the National ResearchCouncil recommended nutrient requirements for pregnant sheep. Between Day60 of pregnancy and parturition control-fed ewes received saline solution and underfed ewes received either saline solution or L-arginine-HCl solution (155mol of arginine/kg body weight) intravenously three times daily (n=5 / treatmentgroup). Birth weights of lambs were lower in saline-infused underfed ewes.There was no difference in birth weights of lambs from control-fed and argininetreatedunderfed ewes. The third experiment determined whether administrationof arginine could improve survival rates of lambs and enhance fetal growth inewes carrying multiple fetuses. Between Days 100 and 121 of pregnancy, ewesreceived an intravenous infusion of either saline solution (n= 14) or L-arginine-HCl solution (345 mol of arginine/kg body weight, n=20) three times daily.Parenteral administration of arginine increased the percentage of lambs bornalive and enhanced the birth weights of quadruplets. Collectively, these resultsindicate that 1) parenteral administration of arginine improves pregnancyoutcomes in underfed and prolific ewes; and 2) the use of arginine or citrullinemay have important implications for the design of an effective treatment forpreventing or ameliorating IUGR in mammals.
97

The Neuroendocrinology of Seasonal Aggression in Female Syrian Hamsters

Gutzler, Stephanie 28 July 2009 (has links)
Aggression is a feature of many clinical disorders including autism, Alzheimer’s disease, bipolar disorder, and schizophrenia. The available treatment options act to prevent impulsive aggression through modulation of GABAergic and dopaminergic pathways which come with metabolic and dyskinetic side effects. The mechanism underlying aggressive motivation, however, has not been elucidated. In addition, previous studies have been heavily biased towards males of various species. Mimicking changes in day length, or photoperiod, in the laboratory is a natural manipulation used to examine seasonal changes in aggressive behavior in many species. In response to the reduction in the duration of light exposure, animals undergo gonadal regression and become reproductively quiescent. During this non-breeding season in male photoperiod-responsive animals, aggressive behavior increases significantly. Although studies have shown offensive aggression remains elevated in female rodents, seasonal regulation of this behavior in females has not been thoroughly studied. The neuropeptide arginine-vasopressin (AVP) has been implicated in the facilitation of aggressive behavior in male rodents and fishes; therefore, it is useful to examine AVP as a modulator of seasonal aggression in females. Because the actions of AVP in female social behavior may be hormonally-dependent, we investigated the hormonal mechanisms that regulate the expression of AVP receptors and the behavioral actions of AVP on aggression. In addition to changes in gonadal steroid hormones during the non-breeding season, we identified photoperiod-dependent alterations in adrenal hormone secretion as AVP plays a role in regulation of hypothalamic-pituitary-adrenal axis (HPA) activity and anxiety-like behaviors in animal models.
98

Discovery of Novel Cross-Talk between Protein Arginine Methyltransferase Isoforms and Design of Dimerization Inhibitors

Canup, Brandon S 17 April 2013 (has links)
Protein arginine methyltransferase, PRMT, is a family of epigenetic enzymes that methylate arginine residues on histone and nonhistone substrates which result in a monomethylation, symmetric dimethylation or asymmetric dimethylation via the transfer of a methyl group from S-adenosyl-L-methionine (SAM). We discovered a novel interaction between two PRMT isoforms: PRMT1 interacts and methylates PRMT6. In this study site-directed mutagenesis was performed on selected arginines identified from tandem mass spectrometric analysis to investigate major methylation sites of PRMT6 by PRMT1. In combination with radiometric methyltransferase assays, we determined two major methylation sites. Methylations at these sites have significant effects on the nascent enzymatic activity of PRMT6 in H4 methylation. PRMTs have the ability to homodimerize which have been linked to methyltransferase activity. We designed dimerization inhibitors (DMIs) to further investigate the need for dimerization for enzyme activity. Preliminary results suggest that the monomeric form of PRMT1 retains methyltransferase activity comparable to that of the uninhibited PRMT1.
99

Arginine and fetal growth in ovine models of intrauterine growth restriction

Lassala, Arantzatzu Leticia 15 May 2009 (has links)
This research was conducted to test the hypothesis that parenteralarginine supplementation is effective in enhancing birth weights of intrauterinegrowth restricted (IUGR) fetuses. Underfed and prolific ewes were used asexperimental models. The first study characterized the pharmacokinetics ofarginine and citrulline and assessed the potential of citrulline to serve as aprecursor for enhancing arginine availability in fetal and maternal plasma. Sixlate pregnant ewes and their fetuses were instrumented to access arterial andvenous circulations. Intravenous boluses of 155 mol of L-arginine-HCl or Lcitrullineper kg body weight were administered to each ewe. Administration ofcitrulline was more effective than arginine in achieving a sustained increase inconcentrations of arginine in maternal and fetal blood. Accordingly, theclearance rate of citrulline was lower and its biological half-life in maternal bloodgreater, when compared with arginine. The second experiment determined ifadministration of arginine to underfed ewes is effective in ameliorating orpreventing IUGR. Ewes were fed either 100% or 50% of the National ResearchCouncil recommended nutrient requirements for pregnant sheep. Between Day60 of pregnancy and parturition control-fed ewes received saline solution and underfed ewes received either saline solution or L-arginine-HCl solution (155mol of arginine/kg body weight) intravenously three times daily (n=5 / treatmentgroup). Birth weights of lambs were lower in saline-infused underfed ewes.There was no difference in birth weights of lambs from control-fed and argininetreatedunderfed ewes. The third experiment determined whether administrationof arginine could improve survival rates of lambs and enhance fetal growth inewes carrying multiple fetuses. Between Days 100 and 121 of pregnancy, ewesreceived an intravenous infusion of either saline solution (n= 14) or L-arginine-HCl solution (345 mol of arginine/kg body weight, n=20) three times daily.Parenteral administration of arginine increased the percentage of lambs bornalive and enhanced the birth weights of quadruplets. Collectively, these resultsindicate that 1) parenteral administration of arginine improves pregnancyoutcomes in underfed and prolific ewes; and 2) the use of arginine or citrullinemay have important implications for the design of an effective treatment forpreventing or ameliorating IUGR in mammals.
100

Identification of Novel Virulence Genes of Salmonella enterica Using an Array Based Analysis of Cistrons Under Selection

Reynolds, Mollie Megan 2010 May 1900 (has links)
Pools of mutants of minimal complexity but maximal coverage of genes of interest facilitate screening for genes under selection in a particular environment. Prior to this work, mutants were generated by random transposon insertions, which yielded highly complex pools for in vivo studies. Recent advances in polymerase chain reaction (PCR)-based mutagenesis in bacteria using the lambda red recombinase, as well as whole genome sequencing, enable a more directed approach for the generation of mutants. The lambda red approach was used to construct individual mutants in 1,023 Salmonella enterica serovar Typhimurium genes, including almost all genes found in Salmonella, but not in related genera. All the mutations were confirmed simultaneously using a novel amplification strategy to produce labeled ribonucleic acid (RNA) from a T7 RNA polymerase promoter, introduced during the construction of each mutant, followed by hybridization of this labeled RNA to a Typhimurium genome tiling array. To demonstrate the ability to identify fitness phenotypes using our pool of mutants, the pool was subjected to selection by intraperitoneal injection into BALB/c (Bagg Albino) mice and was recovered from the spleen. Changes in the representation of each mutant were monitored using T7 transcripts hybridized to a novel inexpensive minimal microarray. Among the top 120 statistically significant spleen colonization phenotypes, 51 were mutations in genes with no previously known role in this model. Fifteen phenotypes were tested using individual mutants in competitive assays and eleven were confirmed in individual mixed intraperitoneal infection in mice, including the first two examples of attenuation for sRNA mutants in Salmonella. We refer to our method as Array-Based Analysis of Cistrons Under Selection (ABACUS). Among the confirmed mutants identified in the ABACUS screen was a component of the twin arginine transport (Tat) system, tatC, required for transport of folded proteins across the cellular membrane. TatC is the highly conserved component necessary for recognition of the twin arginine containing signal sequence S/T-R-R-x-FL- K. We confirmed [delta] tatC mutants are defective for colonization of the liver and spleen in competitive infections with wild type ATCC14028 after intraperitoneal infection in Salmonella- susceptible (BALB/c). We also found that [delta] tatC mutants were defective for swimming motility, but not swarming motility, which was linked to the ability to elaborate flagellins on the bacterial surface under different conditions.

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