Retraction Note to: Mitochondrial bioenergy alterations in avian HD11 macrophages infected with infectious bronchitis virus.

The Editor-in-Chief has retracted this article [1]. Figures 1A, 1D and 2B (bottom right) are identical with Figures 1A, 1H and 1B respectively in another article [2] which reports a study in a different species. In addition, Table 1 contains data presented in a third article [3], which also reports a study in a different species. The Editor-in-Chief therefore no longer has confidence in the validity of the data and the conclusions drawn. Tereza C. Cardoso disagrees with this retraction. Helena L. Ferreira agrees with this retraction. Sergio E. L. da Silva, Andrea F. Garcia, Felipe E. S. Silva, Roberto Gameiro, Carolina U. F. Fabri and Dielson S. Vieira have not responded to any correspondence about this retraction.

Mitochondrial bioenergy alterations in avian HD11 macrophages infected with infectious bronchitis virus.

To establish an association between mitochondrial dysfunction and apoptosis following infectious bronchitis virus (IBV) infection, HD11 avian macrophage cells were infected with the Massachusetts 41 (M41) strain. Our results show that the M41 strain of IBV induced cytopathic effects followed by the release of new viral particles. Elevated numbers of apoptotic cells were observed at 24, 48 and 72 h post-infection (p.i.). Viral infection was associated with mitochondrial membrane depolarization and reactive oxygen species (ROS) production at all of the examined timepoints p.i. In summary, IBV M41 replication in infected HD11 macrophages seems to induce mitochondrial bioenergy failure, acting as a respiratory chain uncoupler, without compromising viral replication.

Production and Purification of Cysteine-Rich Leptospiral Virulence-Modifying Proteins with or Without mCherry Fusion.

Recombinant fluorescent fusion proteins are fundamental to advancing many aspects of protein science. Such proteins are typically used to enable the visualization of functional proteins in experimental systems, particularly cell biology. An important problem in biotechnology is the production of functional, soluble proteins. Here we report the use of mCherry-fusions of soluble, cysteine-rich, Leptospira-secreted exotoxins in the PF07598 gene family, the so-called virulence modifying (VM) proteins. The mCherry fusion proteins facilitated the visual detection of pink colonies of the VM proteins (LA3490 and LA1402) and following them through lysis and sequential chromatography steps. CD-spectroscopy analysis confirmed the stability and robustness of the mCherry-fusion protein, with a structure comparable to AlphaFold structural predictions. LA0591, a unique member of the PF07598 gene family that lacks N-terminal ricin B-like domains, was produced without mCherry tag that strengthens the recombinant protein production protocol without fusion protein as well. The current study provides the approaches for the synthesis of 50-125 kDa soluble, cysteine-rich, high-quality fast protein liquid chromatography (FPLC)-purified protein, with and without a mCherry tag. The use of mCherry-fusion proteins enables a streamlined, efficient process of protein production and qualitative and quantitative downstream analytical and functional studies. Approaches for troubleshooting and optimization were evaluated to overcome difficulties in recombinant protein expression and purification, demonstrating biotechnology utility in accelerating recombinant protein production.

mCherry Fusion Proteins Facilitate Production of Recombinant, Cysteine-Rich Leptospira interrogans Proteins in Escherichia coli.

Background: Recombinant fluorescent fusion proteins are fundamental to advancing many aspects of protein science. Such proteins are typically used to enable the visualization of functional proteins in experimental systems, particularly cell biology. An important problem in biotechnology is the production of functional, soluble proteins. Here we report the use of mCherry-fusions of soluble, cysteine-rich, Leptospira-secreted exotoxins in the PF07598 gene family, the so-called virulence modifying (VM) proteins. Results: The mCherry fusion proteins facilitated the production of the VM proteins (LA3490 and LA1402) by enabling the visual detection of pink colonies and following them through lysis and sequential chromatography steps. CD-spectroscopy analysis confirmed the stability and robustness of the mCherry-fusion protein, with a structure comparable to AlphaFold structural predictions. LA0591, a unique member of the PF07598 gene family that lacks N-terminal ricin B-like domains, was produced as a tagless protein that strengthens the recombinant protein production protocol. The current study provides the approaches for the synthesis of 50-125 kDa soluble, cysteine-rich, high-quality mCherry tagged or tagless fast protein liquid chromatography (FPLC)-purified protein. Conclusions: The use of mCherry-fusion proteins enables a streamlined, efficient process of protein production and qualitative and quantitative downstream analytical and functional studies. Approaches for troubleshooting and optimization were systemically evaluated to overcome difficulties in recombinant protein expression and purification, demonstrating biotechnology utility in accelerating recombinant protein production.

Comparison of the PF07598-Encoded Virulence-Modifying Proteins of L. interrogans and L. borgpetersenii.

Leptospirosis is an emerging infectious disease, with increasing frequency and severity of outbreaks, a changing epidemiology of populations at risk, and the emergence of new strains, serovars, serogroups, and species. Virulence-modifying (VM) proteins encoded by the PF07598 gene family are hypothesized to be Leptospira-secreted exotoxins that mediate the molecular and cellular pathogenesis of severe and fatal leptospirosis. If confirmed experimentally, this concept could revolutionize the treatment, diagnosis, prognosis, and vaccine-mediated prevention of leptospirosis by enabling a novel array of targeted interventions. VM proteins, as with other bacterial-secreted protein exotoxins, mediate their virulence effects by attaching to eukaryotic cells, competing with other microorganisms for limited resources in environmental niches, directly intoxicating target cells, and disrupting their function in the mammalian host. In contrast with the most pathogenic group of Lept ospira, particularly L. interrogans, whose genomes contain 12-15 PF07598 paralogs, strains of the livestock and human pathogen L. borgpetersenii have two PF07598 paralogs. Given the possible non-environmentally mediated transmission of some L. borgpetersenii strains and the much smaller number of VM proteins in this species, their role in infection and disease may well differ from other leptospiral species. Comparison of VM proteins from different clades of pathogenic Leptospira may deepen our understanding of leptospirosis's pathogenesis, leading to novel approaches to ameliorating Leptospira infection in humans and animals.

Antimicrobial activity of propolis extract fractions against Staphylococcus spp. isolated from goat mastitis / Atividade antimicrobiana de frações do extrato de própolis frente à Staphylococcus spp. isolados de mastite caprina

The indiscriminate use of antibiotics in the treatment of caprine mastitis causes the appearance of resistant microorganisms, besides leaving residues in milk, putting at risk to human health. In this way, propolis is an alternative in the treatment of diseases because it has antimicrobial activity, mainly because of the presence of flavonoids in its composition. The aim of this study was to evaluate the antimicrobial potential of propolis to Staphylococcus spp. Isolated from cases of goat mastitis and qualify the crude ethanoic extract by high performance liquid chromatography (HPLC). In this study, the minimum bactericidal concentration values of propolis extracts in ethanol, ethyl acetate and hexane showed that the best concentrations capable of promoting the highest mortality of the isolates of Staphylococcus spp. from mastitis in goats, were 6250, 3125 and 1562.5µg/mL, respectively. By the microplate adherence test, it was found that 20.78% isolates were not able to form biofilm, 14.70% were classified as moderate and 64.70% were weak and none as a strong biofilm producer. Propolis in its different diluents was able to affect the formation of biofilm and showed a pronounced marked antimicrobial activity against Staphylococcus spp. strains and may be indicated for use in in vivo studies.(AU)

O uso indiscriminado de antibióticos no tratamento de mastite caprina leva ao desenvolvimento de micro-organismos resistentes que poderão estar presentes em alimentos, colocando em risco a saúde humana. Dessa forma, a própolis surge como uma alternativa para o tratamento de doenças por possuir uma ação antimicrobiana, principalmente pela presença de flavonoides em sua composição. O objetivo desse estudo foi avaliar o potencial antimicrobiano da própolis frente à Staphylococcus spp. isolados de casos de mastite caprina e qualificar o extrato etanoico bruto por cromatografia líquida de alta eficiência (CLAE-DAD). Neste estudo, os valores de concentração bactericida mínima (CBM) dos extratos de própolis em álcool etílico, acetato de etila e hexano nos isolados foram de 6250, 3125 e 1562,5µg/mL, respectivamente. Pelo teste de aderência à microplacas, observou-se que 20,78% dos microorganismos, não foram capazes de formar biofilme, 14,70% foram classificados como moderados, 64,70% em fracos e nenhum como forte produtor de biofilme. A própolis em seus diferentes diluentes foi capaz de afetar a formação de biofilme e apresentou significativa atividade antimicrobiana frente a cepas de Staphylococcus spp., podendo ser indicada para utilização em estudos "in vivo".(AU)

Atividade antimicrobiana in vitro do extrato etanólico bruto da folha da Hymenaea martiana Hayne frente às Staphylococcus spp. e avaliação de seu potencial como desinfetante em cabras / In vitro antimicrobial activity of ethanolic extract of Hymenaea martiana Hayne leaf on strains of Staphylococcus spp. and evaluation of its potential as a disinfectant in goats

Este estudo objetivou avaliar a ação antimicrobiana e antisséptica do extrato etanólico bruto da folha da Hymenaea martiana (Jatobá). O estudo foi realizado no Laboratório de Microbiologia e Imunologia da UNIVASF, na cidade de Petrolina-PE. Os extratos foram preparados utilizando diferentes diluentes, sendo estes: álcool etílico absoluto e a água destilada. Em seguida, foi empregada a técnica da Concentração Inibitória Mínima (MIC) e da Concentração Bactericida Mínima (CBM). Todos os ensaios foram realizados em triplicata. A CBM média do extrato diluído em etanol foi de 358µg/µL e do extrato diluído em água destilada foi igual a 520,82µg/mL. Não houve diferença (P<0,05) quanto à inibição bacteriana para o extrato diluído em álcool etílico absoluto ou água destilada autoclavada. Ao comparar a atividade do extrato diluído em álcool etílico absoluto e a relação com a presença do gene blaZ, observou-se que os isolados negativos para o gene pesquisado apresentaram uma CBM igual a 412,3µg/mL, e, quando comparadas aos que foram positivos para o gene blaZ, que foi de 308,80µg/mL, contudo sem diferença estatística. Quanto à inibição das bactérias utilizando extrato aquoso, a atividade foi igual para as bactérias com ou sem o gene (520,82µg/mL). Desse modo, tanto o extrato diluído em álcool etílico absoluto quanto em agua destilada autoclavada demonstrou atividade antimicrobiana, sugerindo que ocorreu extração de substâncias bioativas. Em relação ao potencial antisséptico, H. martiana teve ação pareada com o cloro, contudo aquele agiu mais rapidamente, enquanto o cloro agiu de modo ideal uma hora após a aplicação; ambos os resultados destacam que o extrato etanólico bruto das folhas de H. martiana possui potencial de combate à proliferação de bactérias ambientais e infecciosas, surgindo como uma forma de prevenir a mastite.(AU)

This study aimed to evaluate the antimicrobial and antiseptic action of the crude ethanolic extract of Hymenaea martiana leaves. The study was conducted at the Laboratory of Microbiology and Immunology of UNIVASF, city of Petrolina, state o Pernambuco. The extracts were prepared using different solvents, such as absolute ethyl alcohol and distilled water. Then, Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) techniques were used. All assays were performed in triplicate. The average of MBC extract diluted in ethanol was 358µg/mL, and the extract diluted in distilled water was equal to 520.82µg/mL. There was no difference (P<0.05) and bacterial inhibition to extract diluted in absolute ethanol or autoclaved distilled water. Comparing the activity of the extract diluted in ethanol and the relation with the presence of blaZ gene, it was observed that the negative strains for there searched gene showed a MBC equal to 412.3µg/mL in relation to those that were positive for blaZ gene, that was 308.80µg/µL, and, however, there was no statistical difference. The bacterial inhibition activity using an aqueous extract was equal for the bacteria that had or not the blaZ gene (520.82µg/mL). Thus, the extract diluted in absolute ethanol in autoclaved distilled water as demonstrated antimicrobial activity, suggesting that occurred extraction of bioactive substances. Regarding the antiseptic potential, H. martiana had the same action of chlorine, although, this acted immediately, while the chlorine action happened properly an hour after the application. Both results pointed out that the crude ethanolic extract of H. martiana leaves has potential to combat the proliferation of environmental and infectious bacteria, emerging as a way to prevent mastitis.(AU)