Vinte e oito bovinos Brangus foram usados para se determinar o efeito da suplementação de cobre e selênio no desempenho, características de carcaça, composição de ácidos graxos no músculo Longissimus dorsi (LD) e na concentração de colesterol sérico e no músculo LD . Os tratamentos foram : 1) C(Controle) - sem a suplementação de cobre e selênio; 2) Se - 2 mg Se/kg de matéria seca na forma de selenito de sódio; 3) Cu- 40 mg Cu/kg de matéria seca na forma de sulfato de cobre; 4) Se/Cu- 2 mg Se/kg de matéria seca na forma de selenito de sódio e 40 mg Cu/kg de matéria seca na forma de sulfato de cobre. O ganho de peso diário aumentou com a suplementação de selênio (P<0,05). A eficiência alimentar foi melhor (P<0,05) nos tratamentos selênio, cobre e selênio/cobre, em relação ao controle. A ingestão de matéria seca não foi alterada pelos tratamentos (P>0,05). A espessura de gordura e composição de ácidos graxos do músculo LD não foram influenciados pelos tratamentos (P>0,05). A concentração sérica de colesterol não foi influenciada pelos tratamentos (P>0,05), entretanto, a concentração de colesterol no LD foi menor nos bovinos suplementados com cobre e selênio (P < 0.05). A glutationa peroxidase e GSSG aumentaram (P<0,05) com a suplementação de cobre , selênio ou selênio/cobre (P <0,05). / Twenty eight Brangus steers were used to determine the effects of copper (Cu) and selenium (Se) supplementation on performance, carcass characteristics, Longissimus dorsi muscle fatty acid composition and serum and Longissimus dorsi muscle cholesterol concentrations. Treatments were: 1) control - no supplemental Cu and Se; 2) Se - 2 mg Se/kg DM as sodium selenite; 3) Cu - 40 mg Cu/kg DM as copper sulfate; 4) Se/Cu - 2 mg Se/kg DM as sodium selenite and 40 mg Cu/kg DM as copper sulfate. Daily weight gain increased with selenium supplementation (P<0,05). Feed efficiency was better in selenium, copper and selenium/copper treatments than in the control group. Dry matter intake was not affected by treatments (P>0.05). Backfat and Longissimus dorsi fatty acid concentrations were not affected by treatments (P > 0.05). Serum cholesterol concentration was not affected by treatments (P>0.05), however, Longissimus dorsi cholesterol concentrations were lower in steers supplemented with Cu and Se (P<0.05). GSSG and GSH Px increased (P<0.05) with Cu, Se and Se/Cu supplementation.

No description available.

abstract: Synechocystis sp. PCC 6803 is a readily transformable cyanobacteria used to study cyanobacterial genetics, as well as production of biofuels, polyesters, and other industrial chemicals. Free fatty acids are precursors to biofuels which are used by Synechocystis cells as a means of energy storage. By genetically modifying the cyanobacteria to expel these chemicals, costs associated with retrieving the products will be reduced; concurrently, the bacteria will be able to produce the products at a higher concentration. This is achieved by adding genes encoding components of the Escherichia coli AcrAB-TolC efflux system, part of the resistance-nodulation-division (RND) transporter family, to Synechocystis sp. PCC 6803. AcrAB-TolC is a relatively promiscuous multidrug efflux pump that is noted for expelling a wide range of substrates including dyes, organic solvents, antibiotics, and free fatty acids. Adding components of the AcrAB-TolC multidrug efflux pump to a previously created high free fatty acid producing strain, SD277, allowed cells to move more free fatty acids to the extracellular environment than did the parent strain. Some of these modifications also improved tolerance to antibiotics and a dye, rhodamine 6G. To confirm the function of this exogenous efflux pump, the genes encoding components of the AcrAB-TolC efflux pump were also added to Synechocystis sp. PCC 6803 and shown to grow on a greater concentration of various antibiotics and rhodamine 6G. Various endogenous efflux systems have been elucidated, but their usefulness in expelling products currently generated in Synechocystis is limited. Most of the elucidated pumps in the cyanobacteria are part of the ATP-binding cassette superfamily. The knowledge of the resistance-nodulation-division (RND) family transporters is limited. Two genes in Synechocystis sp. PCC 6803, slr2131 and sll0180 encoding homologs to the genes that encode acrB and acrA, respectively, were removed and the modifications resulted in changes in resistance to various antibiotics and a dye and also had an impact on free fatty acid secretion. Both of these deletions were complemented independently with the homologous E. coli gene and the resulting cyanobacteria strains had some of the inherent resistance restored to chloramphenicol and free fatty acid secretion was modified when compared to the wild-type and a high free fatty acid producing strain. / Dissertation/Thesis / Doctoral Dissertation Microbiology 2018

Introdução: Evidências experimentais, epidemiológicas e clínicas mostram o papel da inflamação na patogênese de desordens metabólicas, sendo a modulação da resposta inflamatória associada a quantidade e a qualidade dos ácidos graxos (AG) da dieta. Polimorfismos de nucleotídeo único (SNP) podem influenciar a relação entre AG e concentração plasmática de biomarcadores inflamatórios. Objetivo: Verificar a associação de SNP relacionados aos genes da adiponectina, Receptor do tipo Toll (TLR)-4, interleucina (IL)-1 e IL-6 e ingestão de lipídios com um padrão inflamatório sistêmico, baseado na concentração plasmática de onze biomarcadores inflamatórios em estudo de base populacional ISA-Capital. Metodologia: O presente estudo compreende adultos (20 a 59 anos) do estudo de base populacional, ISA-capital 2008-2010 (n=302). A coleta dos dados dietéticos foi realizada por meio de recordatório de 24 horas, aplicado em duplicata. A partir do plasma, foram determinadas as concentrações plasmáticas de adiponectina, proteína C reativa (PCR), IL-1, IL-6, IL-8, IL-10, fator de necrose tumoral-alfa, IL- 12p70, Quimiocina C-C motif ligante (CCL) 2, molécula de adesão intercelular solúvel (sICAM)-1 e molécula de adesão celular vascular solúvel (sVCAM)-1, por meio da técnica multiplex de imunoensaio, e o perfil de ácidos graxos (AG) do plasma por cromatografia gasosa. A partir do DNA genômico foi realizada a genotipagem dos SNP relacionados aos genes da adiponectina (rs266729, rs17300539, rs16861209, rs1501299 e rs2241766), TLR4 (rs4986790, rs4686791, rs5030728, rs11536889), IL-1 (rs1143623, rs16944, rs1143627, rs1143634 e rs1143643) e da IL-6 (rs1800795, rs1800796, rs1800797) pelo sistema Taqman Open Array. Uma análise multivariada de Cluster (k-means) foi realizada para separar os indivíduos legíveis entre grupo inflamado (INF), n=93, e grupo não inflamado (NINF),n=169, segundo a concentração plasmática dos onze 8 biomarcadores inflamatórios avaliados. Resultados: Todos os SNP estavam em equilíbrio de Hardy-Wienberg (n=301). O INF apresentou idade, circunferência da cintura, pressão arterial e concentrações de triacilgliceróis sanguíneo estatisticamente maiores que aqueles observados para o NINF. O INF apresentou concentração plasmática de AG palmítico (C16:0), razões AG saturados (AGS)/AG ômega-6 (n-6) e AGS/ AG poli-insaturados (AGPI) e atividade estimada da enzima estearoil CoA desaturase aumentadas e concentrações plasmática de AGPI, n-6 e AG araquidônico (AA) e atividade estimada da enzima delta-5-dessaturase (D5D) reduzidas em comparação com o NINF. Interações SNP-AG plasmáticos estatisticamente significantes para predisposição ao padrão inflamatório sistêmico foram detectadas entre o SNP +6054 G>A (rs1143643) do gene da IL-1 e os AG esteárico, AA e AGPI e atividade estimada da enzima delta-6-desaturase (D6D); entre o SNP +3725 G>C (rs11536889) do gene do TLR-4 e a razão AA/AG eicosapentaenoico (EPA); entre o SNP +45 T>G (rs2241766) do gene da adiponectina e o AG ômega-3 (n-3); entre o SNP -7734 C>A (rs16861209) do gene da adiponectina e AA; e entre o SNP -11391 G>A (rs17300539) do gene da adiponectina e AGS. Conclui-se que algumas frações dos AG do plasma podem modular a inflamação e que SNP localizados nos genes da adiponectina, TLR-4, IL- 1 e IL-6 podem interagir com as frações de AG do plasma influenciando a chance de desenvolver uma inflamação sistêmica. / Introduction: Experimental, epidemiological and clinical evidences point to a pathogenic role of inflammation on metabolic disorders development, and to the relationship between this inflammatory response and the quantity and quality of dietary fatty acids. Single Nucleotide Polymorphisms (SNP) can modulate the relationship between fatty acids and plasma inflammatory biomarkers levels. Objective: To verify the association between SNP in the genes of adiponectin, TLR- 4, IL-1 and IL-6 and dietary fatty acids and their effects to a systemic inflammatory pattern at a population-based study ISA-Capital. Methods: This study sample was composed by adults (20 to 59 years), participants of the population-based study ISAcapital 2008-2010 (n=302). Dietary data was collected using two 24 hours dietary recall. Plasma concentration of adiponectin, C reactive protein, IL-1, IL-6, IL-8, IL- 10, tumor necrosis factor-alfa, IL-12p70, Chemokine C-C motif ligand (CCL) 2, soluble intercellular adhesion molecule (sICAM)-1 and soluble vascular cell adhesion molecule (sVCAM)-1 was determined by multiplex immunoassay. Plasma FA profile was determined by gas chromatography. SNP from adiponectin (rs266729, rs17300539, rs16861209, rs1501299 e rs2241766), TLR4 (rs4986790, rs4686791, rs5030728, rs11536889), IL-1 (rs1143623, rs16944, rs1143627, rs1143634 e rs1143643) and IL-6 (rs1800795, rs1800796, rs1800797) gene were genotyped by Taqman Open Array system. A Cluster multivariate analysis (k-means) was conducted to separate individual into inflammatory group (INF), n=93, and noninflammatory group (NINF), n=169, according to eleven inflammatory biomarkers plasma levels. Results: All the SNP were in Hardy-Weinberg equilibrium (n=301). INF had statistically higher age, waist circumference, blood pressure and plasma tryglicerides concentration than NINF. INF presented statistically higher plasma palmitic acid (C16:0) levels, saturated fatty acid (SFA)/omega-6 fatty acid (n-6) ratio and SFA/polyunsaturated fatty acid (PUFA) ratio and estimated stearoil CoA 10 desaturase activity, and statistically lower plasma PUFA, n-6 and arachidonic acid e (AA) and estimate delta-5-desaturase (D5D) activity in comparison to NINF. Statistically significant SNP-plasma fatty acid interactions were found between SNP +6054 G>A (rs1143643) of IL-1 gene and stearic acid, AA and PUFA and estimate delta-6-desaturase (D6D) activity; between SNP +3725 G>C (rs11536889) of TLR-4 gene and AA/eicosapentaenoic acid (EPA) ratio; between SNP +45 T>G (rs2241766) of adiponectin gene and omega-3 fatty acid (n-3); between SNP -7734 C>A (rs16861209) of adiponectin gene and AA; and between SNP -11391 G>A (rs17300539) of adiponectin gene and SFA. In conclusion, some plasma fatty acid subfractions can modulate inflammation and SNP of adiponectin, TLR-4, IL-1 and IL-6 genes can interact with plasma fatty acids to modulate the chance to develop systemic inflammation.

Objetivou-se avaliar a influência da condição sexual sobre o desempenho, características de carcaça e qualidade da carne de bovinos Angus x Nelore, terminados em confinamento. Foram utilizados 176 bovinos, com idade média de 20 meses, pertencentes ao Programa Brasileiro de Carne Angus Certificada, divididos em quatro condições sexuais (CS): 32 machos não castrados (NC), 48 machos castrados cirurgicamente (CC), 48 machos imunocastrados (IM) e 48 fêmeas (F). Para a imunocastração dos bovinos, foram utilizadas três doses de uma vacina anti-GnRH. Os animais foram confinados durante 190 dias, com a mesma dieta, composta de 80% de concentrado e 20% de volumoso na matéria seca. Ao final deste período, os bovinos foram abatidos. Durante o abate, foi calculado o rendimento de carcaça quente (RCQ) e avaliado o pH. Na desossa, foi avaliada no m. Longissimus a área de olho de lombo (AOL), espessura de gordura subcutânea (EGS) entre a 12ª e 13ª costelas, marmorização, cor e pH. Foram coletadas amostras de 2,54 cm de espessura do m. Longissimus, embaladas a vácuo e maturadas por zero (sem maturação), 7 e 14 dias, a 2°C para análises de maciez objetiva (FC) e subjetiva, perdas por cocção (PPC), teor de extrato etéreo (EE) e perfil de ácidos graxos. Utilizou-se o procedimento MIXED do programa SAS® e a significância foi declarada quando P &le; 0,05. Os machos NC apresentaram maior peso vivo final, ganho de peso médio diário, AOL e maiores valores de pH em relação às demais condições sexuais (P &lt; 0,01). Para PCQ, os machos NC e IM apresentaram valores mais elevados do que machos CC e fêmeas (P &lt; 0,01). Por outro lado, as fêmeas apresentaram maior EGS em relação às demais categorias (P &lt; 0,01). O escore de marmorização foi maior na carne das fêmeas e machos CC do que dos machos NC e IM (P &lt; 0,01), no entanto, a carne dos machos CC apresentou maior escore de gordura intramuscular Prime do que a carne das fêmeas. Para RCQ não houve diferença entre as CS. Houve maior PPC na carne dos machos CC (P &lt; 0,01) e a carne das fêmeas apresentou maior teor de EE em relação às demais categorias (P = 0,0248). Houve interação entre CS e dias de maturação para os valores de FC (P = 0,0002) e para os valores de L* (P = 0,0118) e b* (P = 0,0113). A maturação influenciou a cor da carne, em função da CS e ambas favoreceram a maciez da carne de todas as CS avaliadas, especialmente de machos NC e fêmeas. A CS influenciou todos os atributos avaliados na análise sensorial (P &lt; 0,05). A carne de fêmeas e animais castrados, sejam imunocastrados ou castrados por método cirúrgico, apresentaram melhor aceitação pelos consumidores na análise. Adicionalmente, a carne das fêmeas apresentou PAG mais favorável à saúde humana, enquanto a carne dos machos NC apresentou um perfil de AG menos saudável (P &lt; 0,05). A imunocastração pode ser uma alternativa à castração cirúrgica, pois os resultados associados à melhoria na qualidade da carne de bovinos cruzados Angus x Nelore, são similares aos encontrados para os machos CC. Entretanto, vale ressaltar que os bovinos CC produzem carne com maior deposição de gordura intramuscular do que os IM e que os custos financeiros da imunocastração devem ser levados em consideração para a produção da carne. Ainda, as diferenças no perfil de ácidos graxos podem indicar que a CS pode impactar o valor nutricional da carne em termos de saúde humana. / The goal of this work was to evaluate sexual condition effects on performance, carcass traits, and meat quality of a feedlot Angus x Nellore cattle. Were used 176 cattle, 20 months of age, from the Brazilian Certified Angus Beef Program, assigned into four sexual conditions: 32 bulls, 48 steers, 48 immunocastrated, and 48 heifers. The immunocastrated were obtained by vaccinating three times with anti-GnRH vaccine. Animals were fed ad libitum with a highgrain diet containing 80% concentrate. At the end of the experimental period (190 days) the animals were harvested. At the slaughter were collected data related to the carcass yield and pH values. After slaughter, were evaluated in Longissimus muscle, the rib eye area, and subcutaneous fat thickness between the 12th and 13th ribs, marbling score, color, and pH. Vacuum packaged steaks (2.54 cm thick) from the Longissimus muscle were collected, aging for zero, 7, and 14 days at 2°C and stored at -18°C until analysis of meat quality. Statistical analyzes were performed using the proc MIXED SAS® program (version 9.2). Bulls presented increased final body weight, average daily gain, rib eye area, and pH values when compared with the other sexual conditions (P &lt; 0.01). For hot carcass weight, bulls and immunocastrated had higher values compared to steers and heifers (P &lt; 0.01). Interestingly, heifers presented higher subcutaneous fat thickness compared to the other categories (P &lt; 0.01). Heifers and steers presented increased intramuscular fat scores compared to the bulls and immunocastrated; however, beef from steers presented higher marbling Prime scores when compared with beef from heifers. Beef from steers had higher cooking loss (P &lt; 0.01) and beef from heifers presented higher ether extract content when compared with other sexual conditions (P = 0.0248). There was interaction between sexual condition and aging time for Warner Bratzler Shear Force (WBSF) values (P = 0.0002), L* (P = 0.0118) and b* (P = 0.0113) values. The period of aging affected beef color, depending of the sexual condition. In addition, all cattle categories evaluated had beef tenderness improved by the aging process and sexual condition, especially beef from bulls and heifers. Sexual condition had main influence in all beef sensorial attributes (P &lt; 0.05). Beef from heifers, steers, and immunocastrated cattle had better consumer´s acceptability in sensory analysis then the beef from bulls. Additionally, beef from heifers presented favorable fatty acid profile for human healthy, while beef from bulls had an unfavorable fatty acid profile (P &lt; 0.05). In conclusion, immunocastration can be an alternative to surgical castration, since it improves meat quality with results like those for Angus x Nellore steers. However, it is important to highlight that the steers produce high intramuscular fat deposition then the immunocastrated, and the cost of immunocastration should be taken into consideration for the beef cattle production. Additionally, the difference on fatty acid profile can indicate that the sexual condition can impact the nutrition values of the meat.

Hemolysin toxin produced and secreted by pathogenic Escherichia coli is one of a family of cytolytic, structurally homologous protein toxins known as RTX (repeats in toxin) toxins. RTX toxins are products of a gene cluster, CABD . The A gene product, nontoxic hemolysin (proHlyA) is made toxic by post-translational fatty acylation of two internal lysine residues. HlyC, C gene product, is essential for acylation, and acyl-acyl carrier protein (ACP) is the acyl donor. HlyB and HlyD are involved in secretion of the toxin. HlyC was thought to serve as an internal protein acyltransferase and remained uncharacterized until now. ProHlyA and HlyC were separately subcloned, expressed, and purified, and acyl-ACPs with diverse radioactive acyl groups were synthesized. With these proteins, the conversion of proHlyA to HlyA by acyltransfer was assayed. Acyl-ACP was the obligate acyl donor. Acyltransfer was catalyzed by HlyC monomer, and an acyl-enzyme intermediate was detected and shown to catalyze the reverse reaction. The reaction mechanism was examined by steady state kinetics, and the nature of inhibitions by reaction products was determined. The kinetic mechanism of the internal protein acylation was compatible with an uni uni iso uni uni ping pong with isomerization of the F form of the enzyme. Clues to the chemical mechanism for the acyltransferase were elucidated by both chemical modification studies and site directed mutagenesis of the enzyme. Chemical modification experiments ruled out any critical cysteines, serines, and lysine residues, but suggested a role for histidine(s) and tyrosine(s) in acyltransferase function. In order to examine the function of specific residues and possibly corroborate the chemical findings, site directed mutagenesis studies of the acyltransferase were employed. Seventeen residues that were conserved among 13 different RTX toxin acyltransferases were individually mutated, and the respective HlyCs expressed, and characterized. Residues that were critical for acyltransferase function included Gly 11, His 23, Tyr 70, and Gly 85. As with chemical modification data, mutagenesis ruled out any conserved, essential, cysteines or serines critical for HlyC acyltransferase activity.

abstract: Trichloroethene (TCE) is a ubiquitous soil and groundwater contaminant. The most common bioremediation approach for TCE relies on the process of reductive dechlorination by Dehalococcoides mccartyi. D. mccartyi use TCE, dichloroethene, and vinyl chloride as electron acceptors and hydrogen as an electron donor. At contaminated sites, reductive dechlorination is typically promoted by adding a fermentable substrate, which is broken down to short chain fatty acids, simple alcohols, and hydrogen. This study explored microbial chain elongation (MCE), instead of fermentation, to promote TCE reductive dechlorination. In MCE, microbes use simple substrates (e.g., acetate, ethanol) to build medium chain fatty acids and also produce hydrogen during this process. Soil microcosm using TCE and acetate and ethanol as MCE substrates were established under anaerobic conditions. In soil microcosms with synthetic groundwater and natural groundwater, ethene was the main product from TCE reductive dechlorination and butyrate and hydrogen were the main products from MCE. Transfer microcosms using TCE and either acetate and ethanol, ethanol, or acetate were also established. The transfers with TCE and ethanol showed the faster rates of reductive dechlorination and produced more elongated products (i.e., hexanoate). The microbial groups enriched in the soil microcosms likely responsible for chain elongation were most similar to Clostridium genus. These investigations showed the potential for synergistic microbial chain elongation and reductive dechlorination of chlorinated ethenes. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2019

No description available.

N-Acylethanolamines (NAEs) are bioactive lipids derived from the hydrolysis of the membrane phospholipid N-acylphosphatidylethanolamine (NAPE). In animal systems this reaction is part of the “endocannabinoid” signaling pathway, which regulates a variety of physiological processes. The signaling function of NAE is terminated by fatty acid amide hydrolase (FAAH), which hydrolyzes NAE to ethanolamine and free fatty acid. Our previous work in Arabidopsis thaliana showed that overexpression of AtFAAH (At5g64440) lowered endogenous levels of NAEs in seeds, consistent with its role in NAE signal termination. Reduced NAE levels were accompanied by an accelerated growth phenotype, increased sensitivity to abscisic acid (ABA), enhanced susceptibility to bacterial pathogens, and early flowering. Here we investigated the nature of the early flowering phenotype of AtFAAH overexpression. AtFAAH overexpressors flowered several days earlier than wild type and AtFAAH knockouts under both non-inductive short day (SD) and inductive long day (LD) conditions. Microarray analysis revealed that the FLOWERING LOCUS T (FT) gene, which plays a major role in regulating flowering time, and one target MADS box transcription factor, SEPATALLA3 (SEP3), were elevated in AtFAAH overexpressors. Furthermore, AtFAAH overexpressors, with the early flowering phenotype had lower endogenous NAE levels in leaves compared to wild type prior to flowering. Exogenous application of NAE 12:0, which was reduced by up to 30% in AtFAAH overexpressors, delayed the onset of flowering in wild type plants. We conclude that the early flowering phenotype of AtFAAH overexpressors is, in part, explained by elevated FT gene expression resulting from the enhanced NAE hydrolase activity of AtFAAH, suggesting that NAE metabolism may participate in floral signaling pathways.

Given the dramatic rise in obesity and the diseases linked with it, it is becoming increasingly important to understand the mechanisms that underlie the body's ability to recognize fat. The chemoreception of dietary fat in the oral cavity has largely been attributed to activation of the somatosensory system that relays the textural properties of fat. However, the ability of fatty acids, which are believed to represent the proximate stimulus for fat taste, to activate trigeminal ganglionic neurons has remained unexplored. In general, my research has provided the first evidence of fatty acids activating the somatosensory system by increasing the intracellular calcium concentration and generating receptor potentials. Other experiments were focused on identifying fatty acids-responsive pathways in acute isolated trigeminal neurons involved with fat somatosensory perception. My results revealed that fatty acids-activated pathways involved the release of intracellular calcium stores in subpopulations of trigeminal neurons. By using pseudorabies virus as a "live-cell" tracer, a subpopulation of lingual-innervated trigeminal neurons was labeled. Quantitative real-time polymerase chain reaction on individual neurons showed several transient receptor potential channel markers were expressed in these labeled neurons, which indicated the identification of lingual-innervated neurons was successful. This technique helped resolve the problem of trigeminal neurons being a mixed population of cells, and confirmed the role of the release of intracellular calcium stores in fatty acid-activated pathways. Using patch clamp recording, I discovered that the linoleic acid activated signaling pathway involved the activation of G protein and phospholipase C. I further began to characterize the downstream conductance that is activated by linoleic acid in rat trigeminal neurons. Using perforated patch clamp recording, I have recorded linoleic acid-induced currents that exhibited many of the properties of transient receptor potential-like channels, suggesting that this "cellular sensor" is probably playing an important role in the somatosensory perception of fat. Taken together, this dissertation research has revealed the ability of fatty acids to act as effective tactile stimuli and identified several elements of the fatty acids-activated signaling pathway involved in the somatosensory perception of fat.