A genomic view of food-related and probiotic Enterococcus strains

The study of enterococcal genomes has grown considerably in recent years. While special attentionis paid to comparative genomic analysis among clinical relevant isolates, in this study we performedan exhaustive comparative analysis of enterococcal genomes of food origin and/or with potential tobe used as probiotics. Beyond common genetic features, we especially aimed to identify those thatare specific to enterococcal strains isolated from a certain food-related source as well as features presentin a species-specific manner. Thus, the genome sequences of 25 Enterococcus strains, from 7different species, were examined and compared. Their phylogenetic relationship was reconstructedbased on orthologous proteins and whole genomes. Likewise, markers associated with a successfulcolonization (bacteriocin genes and genomic islands) and genome plasticity (phages and clusteredregularly interspaced short palindromic repeats) were investigated for lifestyle specific genetic features.At the same time, a search for antibiotic resistance genes was carried out, since they are of bigconcern in the food industry. Finally, it was possible to locate 1617 FIGfam families as a core proteomeuniversally present among the genera and to determine that most of the accessory genes codefor hypothetical proteins, providing reasonable hints to support their functional characterization.Fil: Bonacina, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Suárez, Nadia Elina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Hormigo, Daniel Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Fadda, Silvina G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Lechner, Marcus. University Marburg; AlemaniaFil: Saavedra, Maria Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentin

Genome mining and transcriptional analysis of bacteriocin genes in enterococcus faecium CRL1879

Among 151 bacterial isolates from nine artisanal cheeses, Enterococcus faecium CRL 1879 showed antibacterialactivity against the food-borne pathogen Listeria monocytogenes. The isolate produced a proteinase K-sensitivecompound in the cell free supernatant. Genome analysis demonstrated the presence of enterocin A, enterocin B,enterocin P, enterocin SE-K4-like and enterocin X biosynthetic gene clusters. Nucleotide sequences encoding for aputative two-component bacteriocin were detected using bioinformatics tools, here named enterocin CRL1879αβ.A transcriptional analysis of all bacteriocin genes by quantitative real time PCR analysis (qRT-PCR) revealed thetranscription of each enterocin gene at different levels. Finally, analysis of bacteriocin genes distribution in 251 E.faecium bioprojects was performed and compared to those identify in E. faecium CRL1879. The discriminative analysisdemonstrated that bacteriocin genes are widely distributed among Enterococcus, independently of the origin of thestrain.The results presented in this paper represent a unique finding since this is the first demonstration of an E. faeciumstrain isolated from an artisanal cheese with the complete genetic machinery to produce six classes II and one class III bacteriocins.Fil: Suárez, Nadia Elina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Bonacina, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Hebert, Elvira Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Saavedra, Maria Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin

Draft Genome Sequence of the Nonstarter Bacteriocin-Producing Strain Enterococcus mundtii CRL35

Enterococcus mundtii CRL35 is a bacteriocinogenic strain isolated from an artisanal cheese of northwestern Argentina. Here we report its draft genome sequence, consisting of 82 contigs. In silico genomic analysis of biotechnological properties was performed to determine the potential of this microorganism to be used in a food model system.Fil: Bonacina, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Saavedra, Maria Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Suárez, Nadia Elina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Sesma, Fernando Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentin

Draft Genome Sequence of the Mannitol-Producing Strain Lactobacillus mucosae CRL573

Lactobacillus mucosae CRL573, isolated from child fecal samples, efficiently converts fructose and/or sucrose into the lowcalorie sugar mannitol when cultured in modified MRS medium at pH 5.0. Also, the strain is capable of producing bacteriocin. The draft genome sequence of this strain with potential industrial applications is presented here.Fil: Bleckwedel, Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Teran, Lucrecia Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Bonacina, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Saavedra, Maria Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Mozzi, Fernanda Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Raya, Raul Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentin

Draft Genome Sequence of Enterococcus faecium Strain CRL 1879, Isolated from a Northwestern Argentinian Artisanal Cheese

We report the draft genome sequence of the bacteriocin producer Enterococcus faecium strain CRL 1879, isolated from a northwestern Argentinian artisanal cheese. The draft genome sequence is composed of 73 contigs for 2,886,747 bp, with 3,140 proteincoding genes. Six biosynthetic clusters for bacteriocin class II production were found. Typical virulence determinants, which have relevance in food safety, were not present.Fil: Suárez, Nadia Elina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Saavedra, Maria Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Složilová, Ivana. Institute of Chemical Technology; República ChecaFil: Bonacina, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Demnerová, Kateřina. Institute of Chemical Technology; República ChecaFil: Sesma, Fernando Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin

Cobalamin production by Lactobacillus coryniformis: Biochemical identification of the synthetized corrinoid and genomic analysis of the biosynthetic cluster

Background: Despite the fact that most vitamins are present in a variety of foods, malnutrition, unbalanced diets or insufficient intake of foods are still the cause of vitamin deficiencies in humans in some countries. Vitamin B12 (Cobalamin) is a complex compound that is only naturally produced by bacteria and archea. It has been reported that certain strains belonging to lactic acid bacteria group are capable of synthesized water-soluble vitamins such as those included in the B-group, as vitamin B12. In this context, the goal of the present paper was to evaluate and characterize the production of vitamin B12 in Lactobacillus coryniformis CRL 1001, a heterofermentative strain isolated from silage. Results: Cell extract of L. coryniformis CRL 1001, isolated from silage, is able to correct the coenzyme B12 requirement of Salmonella enterica serovar Typhimurium AR 2680 in minimal medium. The chemical characterization of the corrinoid-like molecule isolated from CRL 1001 cell extract using HPLC and mass spectrometry is reported. The majority of the corrinoid produced by this strain has adenine like Coα-ligand instead 5,6-dimethylbenzimidazole. Genomic studies revealed the presence of the complete machinery of the anaerobic biosynthesis pathway of coenzyme B12. The detected genes encode all proteins for the corrin ring biosynthesis and for the binding of upper (β) and lower (α) ligands in one continuous stretch of the chromosome. Conclusions: The results here described show for the first time that L. coryniformis subsp. coryniformis CRL 1001 is able to produce pseudocobalamin containing adenine instead of 5,6-dimethlbenzimidazole in the Coα-ligand. Genomic analysis allowed the identification and characterization of the complete de novo biosynthetic pathway of the corrinoid produced by the CRL 1001 strain.Fil: Torres, Andrea Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Vannini, María Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Bonacina, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Font, Graciela Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Saavedra, Maria Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; ArgentinaFil: Taranto, Maria Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentin

The bacterial tubulin homolog FtsZ generates electrical oscillations

FtsZ, a major cytoskeletal protein in all bacteria and archaea, forms a ring that directs cytokinesis. Bacterial FtsZis considered the ancestral homolog of the eukaryotic microtubule (MT)-forming tubulins, sharing GTPase activityand the ability to assemble into protofilaments, rings, and sheets, but not MTs. Previous studies from ourlaboratory demonstrated that structures of isolated brain MTs spontaneously generate electrical oscillations andbursts of electrical activity similar to action potentials. No information about whether the prokaryotic tubulinsmay share similar properties is available. Here, we obtained by ammonium sulfate precipitation an enrichedprotein fraction of the endogenous FtsZ from wild-type Escherichia coli ATCC 25922 without any transfection oroverexpression of the protein. As revealed by electron microscopy, FtsZ was detected by dot blot analysis andimmunofluorescence that assembled into filaments and sheets in a polymerization buffer. We used the patchclamptechnique to explore the electrical properties of sheets of FtsZ and bacterial cells. Electrical recordingsat various holding potentials ranging from ±200 mV showed a complex oscillatory behavior, with several peakfrequencies between 12 and 110 Hz in the power spectra and a linear mean current response. To confirm theoscillatory electrical behavior of FtsZ we also conducted experiments with commercial recombinant FtsZ, withsimilar results. We also detected, by local field potentials, similar electrical oscillations in K+-depolarized pelletsof E. coli cultures. FtsZ oscillations had a wider range of frequency peaks than MT sheets from eukaryotic origin.The findings indicate that the bacterial cytoskeleton generates electrical oscillators that may play a relevant rolein cell division and unknown signaling mechanisms in bacterial populations.Fil: Carabajal, Monica Patricia Antonella. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo. - Universidad Nacional de Santiago del Estero. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo.; ArgentinaFil: Bonacina, Julieta. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo. - Universidad Nacional de Santiago del Estero. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo.; ArgentinaFil: Scarinci, María Noelia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo. - Universidad Nacional de Santiago del Estero. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo.; ArgentinaFil: Albarracín, Virginia Helena. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cantero, Maria del Rocio. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo. - Universidad Nacional de Santiago del Estero. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo.; ArgentinaFil: Cantiello, Horacio Fabio. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo. - Universidad Nacional de Santiago del Estero. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo.; Argentin

Biocontrol of Listeria monocytogenes in a meat model using a combination of a bacteriocinogenic strain with curing additives

The aim of this work was to evaluate the effect of meat curing agents on the bioprotective activity of the bacteriocinogenic strain, Enterococcus (E.) mundtii CRL35 against Listeria (L.) monocytogenes during meat fermentation. The ability of E. mundtii CRL35 to grow, acidify and produce bacteriocin in situ was assayed in a meat model system in the presence of curing additives (CA). E. mundtii CRL35 showed optimal growth and acidification rates in the presence of CA. More importantly, the highest bacteriocin titer was achieved in the presence of these food agents. In addition, the CA produced a statistical significant enhancement of the enterocin CRL35 activity. This positive effect was demonstrated in vitro in a meat based culture medium, by time-kill kinetics and finally by using a beaker sausage model with a challenge experiment with the pathogenic L. monocytogenes FBUNT strain. E. mundtii CRL35 was found to be a promising strain of use as a safety adjunct culture in meat industry and a novel functional supplement for sausage fermentation, ensuring hygiene and quality of the final product.Fil: Orihuel, Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Bonacina, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Vildoza, María José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Bru Chauve, Elena Magdalena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Vignolo, Graciela Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Saavedra, Maria Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Fadda, Silvina G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin