Novel pathway for corrinoid compounds production in lactobacillus

Vitamin B12 or cobalamin is an essential metabolite for humans, which makes it an interesting compound for many research groups that focus in different producer-strains synthesis pathways. In this work, we report the influence of key intermediaries for cobalamin synthesis added to the culture medium in two Lactobacillus (L.) strains, L. reuteri CRL 1098 and L. coryniformis CRL 1001. Here, we report that addition of Co2+ and 5,6-dimethylbenzimidazole increased the corrinoid compounds production in both strains while addition of L-threonine increased only the corrinoid compounds production by CRL 1001 strain. Then, we purified and characterized by LC-MS the corrinoid compounds obtained. Physiological studies besides in silico analysis revealed that L. reuteri CRL 1098 and L. coryniformis CRL 1001 follow different pathways for the last steps of the corrinoid compounds synthesis.Fil: Torres, Andrea Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Vannini, María Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Font, Graciela Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Saavedra, Maria Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Taranto, Maria Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin

Genome sequence of the cheese-starter strain Lactobacillus delbrueckii subsp. lactis CRL 581

We report the genome sequence of Lactobacillus delbrueckii subsp. lactis CRL 581 (1,911,137 bp, GC 49.7%), a proteolytic strain isolated from a homemade Argentinian hard cheese which has a key role in bacterial nutrition and releases bioactive healthbeneficial peptides from milk proteins.Fil: Hebert, Elvira Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina;Fil: Raya, Raul Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina;Fil: Brown, Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina;Fil: Font, Graciela Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina; Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina;Fil: Savoy, Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina; Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina;Fil: Taranto, Maria Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina

Draft genome sequence of Lactobacillus rhamnosus CRL1505, an immunobiotic strain used in social food programs in Argentina

We report the draft genome sequence of the probiotic Lactobacillus rhamnosus strain CRL1505. This new probiotic strain has been included into official Nutritional Programs in Argentina. The draft genome sequence is composed of 3,417,633 bp with 3,327 coding sequences.Fil: Taranto, Maria Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina;Fil: Villena, Julio Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina;Fil: Salva, Maria Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina;Fil: Alvarez, Gladis Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina; Universidad Nacional de Tucuman. Facultad de Bioquimica, Quimica y Farmacia. Instituto de Bioquimica Clinica Aplicada; Argentina;Fil: Savoy, Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina; Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina;Fil: Font, Graciela Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina; Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina;Fil: Hebert, Elvira Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina

Genomic analysis of vitamin B12 (Cobalamin) biosynthetic cluster in Lactobacillus coryniformis CRL 1001

The vitamin B12 (cobalamin-CBL), a very complex non-polymeric macromolecule synthesized only by some bacteria and archaea, and essential to humans and animals. The highly complicated CBL biosynthesis involves about 30 synthesis steps. We demonstrated that cell extract of Lactobacillus coryniformis CRL 1001 is able to correct the coenzyme B12 requirement of Salmonella enterica serovarTyphimuriumin minimal medium. The aim of this study was the sequencing of CRL1001 genome and the molecular characterization of CBL biosynthesis in this strain. L. coryniformis CRL 1001 genome was sequenced by a whole-genome shotgun (WGS) strategy with an Ion Torrent personal genome machine based upon libraries created using NEBNext DNA library kits. Genomic analysis was done using the RAST annotation Server, Blast algorithms, ISGA and KEGG databases.The draft genome sequence consists of 2,829,178 bases with a mean GC content of 42%. A total of 3,341 coding sequences (CDS) and 82 structural RNAs (58 tRNAs) were predicted. RAST analysis evidenced the presence of at least 30 genes (cob genes) involved in the CBL biosynthesis in CRL 1001 strain. This finding is the first evidence for cobalamin biosynthesis genes in this species. Comparative studies among vitamin B12 producer strains demonstrated that the genetic organization of cob operon is conserved in this strain and these genes are adjacent to the pdu operon and pocR gene. The hem genes (hem A, C, B y L) present in L. coryniformis CRL 1001 genome are located among cob operon in similar way to anaerobic microorganisms. Interestingly, the cblT y cblS genes were identified in CRL1001 strain genome. These genes encode a putative protein kinase and a α-ribasol transporter, respectively. The cblT y cblS genes are present in CBLproducers Listeria sp. strains but absent in CBL-producers L. reuteri strains. The knowledge of cob genes and their regulation in vitamin producer lactic strains constitutes an interesting biotechnological alternative for developing fortified foods.Fil: Torres, Andrea Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Vannini, María Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Sesma, Fernando Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Font, Graciela 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; ArgentinaFil: Taranto, Maria Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaX Congreso Argentino de Microbiología GeneralMar del PlataArgentinaSociedad Argentina de Microbiología Genera

Cloning and heterologous expression of Lactobacillus reuteri uroporphyrinogen III synthase/methyltransferase gene (cobA/hemD): Preliminary characterization

Some strains of Lb. reuteri produce cobalamin (vitamin B12). Cobalamin biosynthesis relies on the sequential action of more than 25 enzymes in a complex metabolic pathway. We have cloned, expressed and characterized the gene in Lb. reuteri that codes for the S-adenosy L-methionine uroprophyrinogen III methyltransferase/synthase (CobA/HemD), a key bifunctional enzyme in the biosynthesis of cobalamin and other tetrapyrrols.Fil: Vannini, María Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Rodríguez, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Vera, José Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: de Valdéz, Graciela F.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Taranto, Maria Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Sesma, Fernando Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin

Effect of daily consumption of Lactobacillus reuteri CRL 1098 on cholesterol reduction in hypercholesterolemic subjects

The effect of daily consumption of a yogurt containing Lactobacillus reuteri CRL 1098 on the lipid profile of hypercholesterolemic subjects was evaluated by performing a prospective, randomized, double-blind, cross-over placebo Controlled clinical study. Participants consumed daily a yogurt containing L. reuteri CRL 1098 or a placebo for four weeks, separated by a wash-out period. Total cholesterol, triacylglycerol, high-density (HDL) and low-density (LDL) lipoprotein levels were assessed at the beginning and at the end of each period. We found a statistically significant reduction of total (-7.86 g/dl) and LDL (-7.02 g/dl) cholesterol in absolute changes (before-after) as well as a decreasing trend in the group receiving the yogurt containing L. reuteri with respect to the placebo group, without detecting changes in HDL-cholesterol and triacylglycerol levels. Our results suggest that low amounts of yogurt (125 g/day) and low doses of the CRL 1098 strain (106 CFU) are sufficient to reduce total and LDL-cholesterol levels in hypercholesterolemic subjects.Fil: Malpeli, Agustina. Ministerio de Salud. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Desarrollo e Investigaciones Pediátricas “Prof. Dr. Fernando E. Viteri”. Hospital de Niños de La Plata; ArgentinaFil: Taranto, Maria Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Cravero, Ricardo C.. Sancor Cooperativas Unidas Limitada.; ArgentinaFil: Tavella, Marina. Ministerio de Salud. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Desarrollo e Investigaciones Pediátricas “Prof. Dr. Fernando E. Viteri”. Hospital de Niños de La Plata; ArgentinaFil: Fasano, Maria Victoria. Ministerio de Salud. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Desarrollo e Investigaciones Pediátricas “Prof. Dr. Fernando E. Viteri”. Hospital de Niños de La Plata; ArgentinaFil: Vicentin, Dimas. Sancor Cooperativas Unidas Limitada.; ArgentinaFil: Ferrari, Guillermina. Ministerio de Salud. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Desarrollo e Investigaciones Pediátricas “Prof. Dr. Fernando E. Viteri”. Hospital de Niños de La Plata; ArgentinaFil: Magrini, Graciano. Sancor Cooperativas Unidas Limitada.; ArgentinaFil: Hebert, Elvira Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Font, Graciela Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Varea, Ana María. Ministerio de Salud. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Desarrollo e Investigaciones Pediátricas “Prof. Dr. Fernando E. Viteri”. Hospital de Niños de La Plata; ArgentinaFil: Tavella, Julio Marcelo. Ministerio de Salud. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Desarrollo e Investigaciones Pediátricas “Prof. Dr. Fernando E. Viteri”. Hospital de Niños de La Plata; ArgentinaFil: González, Horacio F.. Ministerio de Salud. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Desarrollo e Investigaciones Pediátricas “Prof. Dr. Fernando E. Viteri”. Hospital de Niños de La Plata; Argentin

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects