Antimicrobial susceptibility and genetic profile of Mycoplasma hyopneumoniae isolates from Brazil

Mycoplasma hyopneumoniae is the etiologic agent of porcine enzootic pneumonia, responsible for major production losses worldwide. The bacteria have a limited metabolism and need to obtain molecules from the growth environment, which causes multiple difficulties for in vitro culture. These limitations have a negative influence on the ability to carry out research for the development of the rational use of antimicrobials and vaccines. The objective of this investigation was to evaluate the genetic profile and in vitro susceptibility of field isolates of M. hyopneumoniae to different antimicrobials. All 16 isolates obtained from the samples presented 100% of identity in the partial sequence of 16S rRNA gene when compared to M. hyopneumoniae. A dendrogram was created using the PCR results of the genes related to pathogenicity, and the isolates were distributed into four clusters, suggesting genetic variability among four different isolates circulating on the same farm. The minimum inhibitory concentration of the isolates was higher for the antimicrobials tylosin (< 0.001–16 mg/L) and spiramycin (< 0.001–16 mg/L) than for enrofloxacin (< 0.001–0.125 mg/L) and tiamulin (< 0.001–0.125 mg/L). Our results demonstrate the genetic variability among M. hyopneumoniae isolates from pigs of the same farm, with differences in their susceptibility to antimicrobial agents

Influence of Ecto-Nucleoside Triphosphate Diphosphohydrolase Activity on Trypanosoma cruzi Infectivity and Virulence

The protozoan Trypanosoma cruzi is the causative agent of Chagas disease, an endemic zoonosis present in some countries of South and Central Americas. The World Health Organization estimates that 100 million people are at risk of acquiring this disease. The infection affects mainly muscle tissues in the heart and digestive tract. There are no vaccines or effective treatment, especially in the chronic phase when most patients are diagnosed, which makes a strong case for the development of new drugs to treat the disease. In this work we evaluate a family of proteins called Ecto-Nucleoside-Triphosphate-Diphosphohydrolase (Ecto-NTPDase) as new chemotherapy target to block T. cruzi infection in mammalian cells and in mice. We have used inhibitors and antibodies against this protein and demonstrated that T. cruzi Ecto-NTPDases act as facilitators of infection in mammalian cells and virulence factors in mice model. Two of the drugs used in this study (Suramin and Gadolinium) are currently used for other diseases in humans, supporting the possibility of their use in the treatment of Chagas disease

The ER luminal binding protein (BiP) mediates an increase in drought tolerance in soybean and delays drought-induced leaf senescence in soybean and tobacco

The ER-resident molecular chaperone BiP (binding protein) was overexpressed in soybean. When plants growing in soil were exposed to drought (by reducing or completely withholding watering) the wild-type lines showed a large decrease in leaf water potential and leaf wilting, but the leaves in the transgenic lines did not wilt and exhibited only a small decrease in water potential. During exposure to drought the stomata of the transgenic lines did not close as much as in the wild type, and the rates of photosynthesis and transpiration became less inhibited than in the wild type. These parameters of drought resistance in the BiP overexpressing lines were not associated with a higher level of the osmolytes proline, sucrose, and glucose. It was also not associated with the typical drought-induced increase in root dry weight. Rather, at the end of the drought period, the BiP overexpressing lines had a lower level of the osmolytes and root weight than the wild type. The mRNA abundance of several typical drought-induced genes [NAC2, a seed maturation protein (SMP), a glutathione-S-transferase (GST), antiquitin, and protein disulphide isomerase 3 (PDI-3)] increased in the drought-stressed wild-type plants. Compared with the wild type, the increase in mRNA abundance of these genes was less (in some genes much less) in the BiP overexpressing lines that were exposed to drought. The effect of drought on leaf senescence was investigated in soybean and tobacco. It had previously been reported that tobacco BiP overexpression or repression reduced or accentuated the effects of drought. BiP overexpressing tobacco and soybean showed delayed leaf senescence during drought. BiP antisense tobacco plants, conversely, showed advanced leaf senescence. It is concluded that BiP overexpression confers resistance to drought, through an as yet unknown mechanism that is related to ER functioning. The delay in leaf senescence by BiP overexpression might relate to the absence of the response to drought

Regulated Nuclear Trafficking of rpL10A Mediated by NIK1 Represents a Defense Strategy of Plant Cells against Virus

The NSP-interacting kinase (NIK) receptor-mediated defense pathway has been identified recently as a virulence target of the geminivirus nuclear shuttle protein (NSP). However, the NIK1–NSP interaction does not fit into the elicitor–receptor model of resistance, and hence the molecular mechanism that links this antiviral response to receptor activation remains obscure. Here, we identified a ribosomal protein, rpL10A, as a specific partner and substrate of NIK1 that functions as an immediate downstream effector of NIK1-mediated response. Phosphorylation of cytosolic rpL10A by NIK1 redirects the protein to the nucleus where it may act to modulate viral infection. While ectopic expression of normal NIK1 or a hyperactive NIK1 mutant promotes the accumulation of phosphorylated rpL10A within the nuclei, an inactive NIK1 mutant fails to redirect the protein to the nuclei of co-transfected cells. Likewise, a mutant rpL10A defective for NIK1 phosphorylation is not redirected to the nucleus. Furthermore, loss of rpL10A function enhances susceptibility to geminivirus infection, resembling the phenotype of nik1 null alleles. We also provide evidence that geminivirus infection directly interferes with NIK1-mediated nuclear relocalization of rpL10A as a counterdefensive measure. However, the NIK1-mediated defense signaling neither activates RNA silencing nor promotes a hypersensitive response but inhibits plant growth and development. Although the virulence function of the particular geminivirus NSP studied here overcomes this layer of defense in Arabidopsis, the NIK1-mediated signaling response may be involved in restricting the host range of other viruses

Actualization and perspectives of Bachelor degree in Biochemistry from Universidade Federal de Viçosa(UFV) - (Symposium) SBBq Brazil

The Bachelor Degree in Biochemistry of the UFV was  created in 2001 by the Biochemistry and Molecular Biology Department as a  groundbreaking initiative at Brazil. The program was an attempt to assume both academic and biotechnology sectors, preparing capable professionals for the development of new products and biochemical process. Our initial challenge came with the ingress of the first classes bringing doubts related to their formation and action profiles, sometimes confused with clinical analysts or pharmacists. Lecture series with professionals was used to demonstrate the present scenario with a growing market share, instigating discussions about the pedagogic project. The secondchallenge was the student’s pressure to recognition of under graduation programby the Brazilian Education Ministry (MEC) and the biochemical professional recognition by one Regional Council. The bachelor degree was recognized by the MEC in 2004 and the Regional Council of Chemistry became our major partner. The  success of the initiative of the UFV has been giving good results such as the participation in the formation process of the Bachelor Degree in Biochemistry of the Federal University of São João Del Rei (UFSJ) and stimulated the creation of another biochemistry course at State University of Maringá (UEM). The success of our students in Phd programs spread in Brazil evidences the quality of Biochemistry bachelors from UFV. Now the egresses have been recognized by biochemistry and biotechnology industry. However we still face problems with impaired recognition in many federal concourses that do not recognize the Biochemist as a chemistry and biotechnology professional. With high expectative, we wait that the biochemistry bachelordegree spreads widely in the country making possible the opening of new opportunities in all ways

Genótipos de sorgo com potencial para sacarificação.

Entre as novas fontes de biomassa com características ideais para atender os desafios de sustentabilidade e utilização alternativa aos recursos fósseis, encontra-se o sorgo biomassa como uma fonte promissora para a obtenção do etanol de segunda geração. Neste processo de bioconversão da biomassa lignocelulósica em etanol, a principal etapa consiste em estabelecer um pré-tratamento adequado para remover lignina, hemicelulose e reduzir a cristalinidade, bem como o grau de polimerização da celulose, para torná-la mais susceptível à hidrólise enzimática e, consequentemente, à produção de açúcares. O objetivo do trabalho foi analisar a composição química e o potencial de sacarificação de cinco genótipos de sorgo desenvolvidos pela Embrapa e com características bioenergéticas diferentes, sendo dois genótipos de sorgo biomassa tipo bmr (201552B003 e 201552B18), um híbrido biomassa comercial (BRS716), uma linhagem comercial de sorgo sacarino (BRS511) e um genótipo experimental biomassa-sacarino (201641B-138). Os genótipos foram caracterizados quanto aos teores de celulose, hemicelulose, lignina, cinzas e rendimento de glicose após hidrólise enzimática da biomassa (sacarificação). Os dois genótipos de sorgo biomassa bmr e a linhagem comercial de sorgo sacarino (BRS511) apresentaram os menores teores de lignina, porém os genótipos de sorgo bmr apresentaram os maiores teores de hemicelulose. A conversão da biomassa pré-tratada em glicose foi mais eficiente para os genótipos 201552B003, 201552B18 e BRS511, sendo que o genótipo 201552B003 destacou-se por apresentar o maior teor de glicose após 72 horas de sacarificação (0,166 g.g-1). Esses resultados contribuem com informações para a utilização do sorgo biomassa como fonte de matériaprima para a obtenção de açúcares fermentescíveis para produção de bioetanol.bitstream/item/191890/1/bol-182.pd

Production and Characterization of β-Glucanase Secreted by the Yeast Kluyveromyces marxianus

An extracellular β-glucanase secreted by Kluyveromyces marxianus was identified for the first time. The optimal conditions for the production of this enzyme were evaluated by response surface methodology. The optimal conditions to produce β-glucanase were a glucose concentration of 4 % (w/v), a pH of 5.5, and an incubation temperature of 35 °C. Response surface methodology was also used to determine the pH and temperature required for the optimal enzymatic activity. The highest enzyme activity was obtained at a pH of 5.5 and a temperature of 55 °C. Furthermore, the enzyme was partially purified and sequenced, and its specificity for different substrates was evaluated. The results suggest that the enzyme is an endo-β-1,3(4)-glucanase. After optimizing the conditions for β-glucanase production, the culture supernatant was found to be effective in digesting the cell wall of the yeast Saccharomyces cerevisiae, showing the great potential of β-glucanase in the biotechnological production of soluble β-glucan