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The human microbiome is an integral component of the human body and a co-determinant of several health conditions 1 , 2 . However, the extent to which interpersonal relations shape the individual genetic makeup of the microbiome and its transmission within and across populations remains largely unknown 3 , 4 . Here, capitalizing on more than 9,700 human metagenomes and computational strain-level profiling, we detected extensive bacterial strain sharing across individuals (more than 10 million instances) with distinct mother-to-infant, intra-household and intra-population transmission patterns. Mother-to-infant gut microbiome transmission was considerable and stable during infancy (around 50% of the same strains among shared species (strain-sharing rate)) and remained detectable at older ages. By contrast, the transmission of the oral microbiome occurred largely horizontally and was enhanced by the duration of cohabitation. There was substantial strain sharing among cohabiting individuals, with 12% and 32% median strain-sharing rates for the gut and oral microbiomes, and time since cohabitation affected strain sharing more than age or genetics did. Bacterial strain sharing additionally recapitulated host population structures better than species-level profiles did. Finally, distinct taxa appeared as efficient spreaders across transmission modes and were associated with different predicted bacterial phenotypes linked with out-of-host survival capabilities. The extent of microorganism transmission that we describe underscores its relevance in human microbiome studies 5 , especially those on non-infectious, microbiome-associated diseases. Data from more than 9,700 human stool and oral metagenomes has been used to decipher the strain transmission patterns of the human microbiome from mother to infant, within households and within populations.

The persistence of commensal bacteria and administered probiotics in the human gut depends to some extent on their capacity to metabolize diet and host-derived glycans. N , N ′-Diacetylchitobiose ( N -acetylglucosamine-β-1,4- N -acetylglucosamine; ChbNAc) is a component of N -glycosylated proteins and also the major degradation product of chitin. We have identified in Lacticaseibacillus paracasei BL23 a gene cluster, named chb , involved in the catabolism of ChbNAc. The cluster encodes a transcriptional regulator (ChbR), a cellobiose-type phosphoenolpyruvate-dependent sugar phosphotransferase system (PTS) IIC (ChbC), IIA (ChbA) and IIB (ChbB) components, a DUF3284-containing protein (ChbD), and a glycoside hydrolase of the newly identified GH170 family (ChbE). Inactivation of chbC or chbE prevents the growth of L. paracasei in ChbNAc, suggesting that the PTS is involved in its transport and phosphorylation, and that the putative hydrolase ChbE may be acting on the resulting phosphorylated ChbNAc. An L. paracasei mutant with inactivated nagA , encoding an N -acetylglucosamine-6P deacetylase, was also defective in ChbNAc utilization, indicating that the transformation of N -acetylglucosamine-6P into glucosamine-6P by NagA is necessary for ChbNAc metabolism. Transcriptional analysis showed that the chb genes and the nagA gene are regulated by substrate-specific induction mediated by the transcriptional repressors ChbR and NagR, respectively. In addition, both transcriptional regulators repressed the nagB gene, which encodes a glucosamine-6P deaminase that catalyzes the conversion of glucosamine-6P into the glycolytic intermediate fructose-6P. We characterized for the first time the genes responsible for ChbNAc metabolism in a member of the Lactobacillales . The chb and nag clusters may constitute a strategy that allows L. paracasei to adapt to the gastrointestinal environment. Key points • Lacticaseibacillus paracasei BL23 metabolizes N,N’-diacetylchitobiose • The chb and nag gene clusters are involved in N,N’-diacetylchitobiose metabolism • ChbR and NagR transcriptionally repressed the chb and nagAR clusters, respectively

Background. Previous evidence suggests that metabolic disorders in postmenopausal women could be related with low serum vitamin D levels. For example, vitamin D deficiency has been associated with increased risk factors for cardiovascular disease (CVD), mainly those related with metabolic syndrome. Objective. To assess the relationship between the serum vitamin D (25-OH-D) levels and the metabolic syndrome markers in postmenopausal women. Methods. This descriptive and cross-sectional study was conducted in 183 postmenopausal women of four municipalities from Colombian Caribbean. The serum 25-OH-D levels and the anthropometric and biochemical markers were assessed and correlated with metabolic syndrome. Results. The average value of serum vitamin D (25-OH-D) was 26.34 ± 9.08 ng/mL, and 69.95% of the women had vitamin D levels <30 ng/mL, of which 43.72% were with insufficiency (<30 to >20 ng/mL) and 26.23% with deficiency (<20 ng/mL). Of the evaluated women, the 81.42% seemed to have metabolic syndrome. Through the linear regression, one significant positive association was observed between the HDL cholesterol and the 25-OH-D levels (P=0.014). Conclusion. In the evaluated population in this study, vitamin D deficiency is related with low HDL cholesterol levels.

Introducción: la transfusión de sangre es parte esencial del cuidado de la salud. La evaluación continua de todas las actividades de recolección de la sangre y el conocimiento del perfil de los donantes pueden ayudar a la reducción del riesgo de transmisión de enfermedades infecciosas asociadas al proceso. Objetivo: determinar el perfil de los donantes de un banco de sangre de la ciudad de Barranquilla-Colombia y la seroprevalencia de los marcadores infecciosos entre los años 2014 y 2015. Métodos: Estudio descriptivo retrospectivo que incluyó 5,827 datos de variables socio-demográficas y resultados de pruebas infecciosas de donantes de un Banco de Sangre de la ciudad de Barranquilla-Colombia durante los años 2014 y 2015. Resultados: 78,86% de los donantes de sangre fueron voluntarios por primera vez, las participación de la mujer como donante fue significativamente más baja (32,69%) en comparación con los hombres (67,31%), la fuente más importante de donantes fue la captación en campañas de donación (74,19%). El marcador infeccioso más frecuentemente encontrado en los donantes fue Sífilis (1,73%), seguido por Hepatitis B (1,53%), Hepatitis C (0,46%) HTLV I-II (0,21%), la enfermedad de Chagas (0,27%) y VIH (0,17%). Conclusiones: En el banco de sangre estudiado, los donantes voluntarios por primera vez captados en campañas de donación fueron el tipo de donante más frecuente y la mejor fuente de sangre segura.

The gastrointestinal tract accommodates more than 10 14 microorganisms that have an enormous impact on human health. The mechanisms enabling commensal bacteria and administered probiotics to colonize the gut remain largely unknown. The ability to utilize host-derived carbon and energy resources available at the mucosal surfaces may provide these bacteria with a competitive advantage in the gut. Here, we have identified in the commensal species Lactobacillus casei a novel metabolic pathway for the utilization of the glycoamino acid fucosyl-α-1,6- N -GlcNAc-Asn, which is present in the core-fucosylated N -glycoproteins from mammalians. These results give insight into the molecular interactions between the host and commensal/probiotic bacteria and may help to devise new strategies to restore gut microbiota homeostasis in diseases associated with dysbiotic microbiota. The survival of commensal bacteria in the human gut partially depends on their ability to metabolize host-derived molecules. The use of the glycosidic moiety of N -glycoproteins by bacteria has been reported, but the role of N -glycopeptides or glycoamino acids as the substrates for bacterial growth has not been evaluated. We have identified in Lactobacillus casei strain BL23 a gene cluster ( alf-2 ) involved in the catabolism of the glycoamino acid fucosyl-α-1,6- N -GlcNAc-Asn (6′FN-Asn), a constituent of the core-fucosylated structures of mammalian N -glycoproteins. The cluster consists of the genes alfHC , encoding a major facilitator superfamily (MFS) permease and the α- l -fucosidase AlfC, and the divergently oriented asdA (aspartate 4-decarboxylase), alfR2 (transcriptional regulator), pepV (peptidase), asnA2 (glycosyl-asparaginase), and sugK (sugar kinase) genes. Knockout mutants showed that alfH , alfC , asdA , asnA2 , and sugK are necessary for efficient 6′FN-Asn utilization. The alf-2 genes are induced by 6′FN-Asn, but not by its glycan moiety, via the AlfR2 regulator. The constitutive expression of alf-2 genes in an alfR2 strain allowed the metabolism of a variety of 6′-fucosyl-glycans. However, GlcNAc-Asn did not support growth in this mutant background, indicating that the presence of a 6′-fucose moiety is crucial for substrate transport via AlfH. Within bacteria, 6′FN-Asn is defucosylated by AlfC, generating GlcNAc-Asn. This glycoamino acid is processed by the glycosylasparaginase AsnA2. GlcNAc-Asn hydrolysis generates aspartate and GlcNAc, which is used as a fermentable source by L. casei . These data establish the existence in a commensal bacterial species of an exclusive metabolic pathway likely to scavenge human milk and mucosal fucosylated N -glycopeptides in the gastrointestinal tract. IMPORTANCE The gastrointestinal tract accommodates more than 10 14 microorganisms that have an enormous impact on human health. The mechanisms enabling commensal bacteria and administered probiotics to colonize the gut remain largely unknown. The ability to utilize host-derived carbon and energy resources available at the mucosal surfaces may provide these bacteria with a competitive advantage in the gut. Here, we have identified in the commensal species Lactobacillus casei a novel metabolic pathway for the utilization of the glycoamino acid fucosyl-α-1,6- N -GlcNAc-Asn, which is present in the core-fucosylated N -glycoproteins from mammalians. These results give insight into the molecular interactions between the host and commensal/probiotic bacteria and may help to devise new strategies to restore gut microbiota homeostasis in diseases associated with dysbiotic microbiota.

Fucosyl-N-acetylglucosamine disaccharides are important core structures that form part of human mucosal and milk glyco-complexes. We have previously shown that AlfB and AlfC α-L-fucosidases from Lactobacillus casei are able to synthesize fucosyl-α-1,3--N-acetylglucosamine (Fuc-α1,3-GlcNAc) and fucosyl-α-1,6-N-acetylglucosamine (Fuc-α1,6-GlcNAc), respectively, in transglycosylation reactions. Here, these reactions were performed in a semipreparative scale, and the produced disaccharides were purified. The maximum yields obtained of Fuc-α1,3-GlcNAc and Fuc-α1,6-GlcNAc were 4.2 and 9.3 g/l, respectively. The purified fucosyl-disaccharides were then analyzed for their prebiotic effect in vitro using strains from the Lactobacillus casei/paracasei/rhamnosus group and from Bifidobacterium species. The results revealed that 6 out of 11 L. casei strains and 2 out of 6 L. rhamnosus strains tested were able to ferment Fuc-α1,3-GlcNAc, and L. casei BL87 and L. rhamnosus BL327 strains were also able to ferment Fuc-α1,6-GlcNAc. DNA hybridization experiments suggested that the metabolism of Fuc-α1,3-GlcNAc in those strains relies in an α-L-fucosidase homologous to AlfB. Bifidobacterium breve and Bibidobacterium pseudocatenolatum species also metabolized Fuc-α1,3-GlcNAc. Notably, L-fucose was excreted from all the Lactobacillus and Bifidobacterium strains fermenting fucosyl-disaccharides, except from strains L. rhamnosus BL358 and BL377, indicating that in these latest strains, L-fucose was catabolized. The fucosyl-disaccharides were also tested for their inhibitory potential of pathogen adhesion to human colon adenocarcinoma epithelial (HT29) cell line. Enteropathogenic Escherichia coli (EPEC) strains isolated from infantile gastroenteritis were used, and the results showed that both fucosyl-disaccharides inhibited adhesion to different extents of certain EPEC strains to HT29 cells in tissue culture

Abstract The persistence of commensal bacteria and administered probiotics in the human gut depends to some extent on their capacity to metabolize diet and host-derived glycans. N,N′-Diacetylchitobiose (N-acetylglucosamine-β-1,4-N-acetylglucosamine; ChbNAc) is a component of N-glycosylated proteins and also the major degradation product of chitin. We have identified in Lacticaseibacillus paracasei BL23 a gene cluster, named chb, involved in the catabolism of ChbNAc. The cluster encodes a transcriptional regulator (ChbR), a cellobiose-type phosphoenolpyruvate-dependent sugar phosphotransferase system (PTS) IIC (ChbC), IIA (ChbA) and IIB (ChbB) components, a DUF3284-containing protein (ChbD), and a glycoside hydrolase of the newly identified GH170 family (ChbE). Inactivation of chbC or chbE prevents the growth of L. paracasei in ChbNAc, suggesting that the PTS is involved in its transport and phosphorylation, and that the putative hydrolase ChbE may be acting on the resulting phosphorylated ChbNAc. An L. paracasei mutant with inactivated nagA, encoding an N-acetylglucosamine-6P deacetylase, was also defective in ChbNAc utilization, indicating that the transformation of N-acetylglucosamine-6P into glucosamine-6P by NagA is necessary for ChbNAc metabolism. Transcriptional analysis showed that the chb genes and the nagA gene are regulated by substrate-specific induction mediated by the transcriptional repressors ChbR and NagR, respectively. In addition, both transcriptional regulators repressed the nagB gene, which encodes a glucosamine-6P deaminase that catalyzes the conversion of glucosamine-6P into the glycolytic intermediate fructose-6P. We characterized for the first time the genes responsible for ChbNAc metabolism in a member of the Lactobacillales. The chb and nag clusters may constitute a strategy that allows L. paracasei to adapt to the gastrointestinal environment. Key points • Lacticaseibacillus paracasei BL23 metabolizes N,N’-diacetylchitobiose • The chb and nag gene clusters are involved in N,N’-diacetylchitobiose metabolism • ChbR and NagR transcriptionally repressed the chb and nagAR clusters, respectively

ABSTRACT The survival of commensal bacteria in the human gut partially depends on their ability to metabolize host-derived molecules. The use of the glycosidic moiety of N-glycoproteins by bacteria has been reported, but the role of N-glycopeptides or glycoamino acids as the substrates for bacterial growth has not been evaluated. We have identified in Lactobacillus casei strain BL23 a gene cluster (alf-2) involved in the catabolism of the glycoamino acid fucosyl-α-1,6-N-GlcNAc-Asn (6′FN-Asn), a constituent of the core-fucosylated structures of mammalian N-glycoproteins. The cluster consists of the genes alfHC, encoding a major facilitator superfamily (MFS) permease and the α-l-fucosidase AlfC, and the divergently oriented asdA (aspartate 4-decarboxylase), alfR2 (transcriptional regulator), pepV (peptidase), asnA2 (glycosyl-asparaginase), and sugK (sugar kinase) genes. Knockout mutants showed that alfH, alfC, asdA, asnA2, and sugK are necessary for efficient 6′FN-Asn utilization. The alf-2 genes are induced by 6′FN-Asn, but not by its glycan moiety, via the AlfR2 regulator. The constitutive expression of alf-2 genes in an alfR2 strain allowed the metabolism of a variety of 6′-fucosyl-glycans. However, GlcNAc-Asn did not support growth in this mutant background, indicating that the presence of a 6′-fucose moiety is crucial for substrate transport via AlfH. Within bacteria, 6′FN-Asn is defucosylated by AlfC, generating GlcNAc-Asn. This glycoamino acid is processed by the glycosylasparaginase AsnA2. GlcNAc-Asn hydrolysis generates aspartate and GlcNAc, which is used as a fermentable source by L. casei. These data establish the existence in a commensal bacterial species of an exclusive metabolic pathway likely to scavenge human milk and mucosal fucosylated N-glycopeptides in the gastrointestinal tract. IMPORTANCE The gastrointestinal tract accommodates more than 1014 microorganisms that have an enormous impact on human health. The mechanisms enabling commensal bacteria and administered probiotics to colonize the gut remain largely unknown. The ability to utilize host-derived carbon and energy resources available at the mucosal surfaces may provide these bacteria with a competitive advantage in the gut. Here, we have identified in the commensal species Lactobacillus casei a novel metabolic pathway for the utilization of the glycoamino acid fucosyl-α-1,6-N-GlcNAc-Asn, which is present in the core-fucosylated N-glycoproteins from mammalians. These results give insight into the molecular interactions between the host and commensal/probiotic bacteria and may help to devise new strategies to restore gut microbiota homeostasis in diseases associated with dysbiotic microbiota.

The initial peopling of the remote Pacific islands was one of the greatest migrations in human history, beginning three millennia ago by Lapita cultural groups. The spread of Lapita out of an ancestral Asian homeland is a dominant narrative in the origins of Pacific peoples, and although Island New Guinea has long been recognized as a springboard for the peopling of Oceania, the role of Indigenous populations in this remarkable phase of exploration remains largely untested. Here, we report the earliest evidence for Lapita-introduced animals, turtle bone technology and repeated obsidian import in southern New Guinea 3,480–3,060 years ago, synchronous with the establishment of the earliest known Lapita settlements 700 km away. Our findings precede sustained Lapita migrations and pottery introductions by several centuries, occur alongside Indigenous technologies and suggest continued multicultural influences on population diversity despite language replacement. Our work shows that initial Lapita expansion throughout Island New Guinea was more expansive than previously considered, with Indigenous contact influencing migration pathways and island-hopping strategies that culminated in rapid and purposeful Pacific-wide settlement. Later Lapita dispersals through New Guinea were facilitated by earlier contact with Indigenous populations and profoundly influenced the region as a global centre of cultural and linguistic diversity. Excavation in Island New Guinea reveals features associated with the Pacific Lapita cultural complex as well as sustained local cultural traditions from 3,480–3,060 years ago, contemporary with the earliest known Lapita settlements 700 km away. This supports New Guinea as a springboard for Lapita dispersal throughout the Pacific and illuminates their origins.

El presente trabajo de investigación pretende describir como los proyectos de perforación diamantina podrían verse beneficiados con el uso de metodologías ágiles como una herramienta más para su gestión. En tiempos donde todo está evolucionando y cambiando, la manera en la que dirigimos y gestionamos los proyectos de perforación diamantina debe estar enmarcado dentro de la política empresarial de las compañías que realizan esta actividad y de los clientes que contratan estos servicios. De esta forma la exigencia e innovación se hacen necesarios para optimizar los recursos con los que se cuenta, y cumplir de forma eficiente los objetivos planificados al inicio de la campaña. La perforación diamantina entre otras cosas nos ofrece la posibilidad de calcular con certeza el valor económico de un recurso mineral teniendo en esta actividad una oportunidad de mejora en cuanto se refiere a su planificación y gestión. Algunas compañías a modo de buenas prácticas desarrollan sus proyectos de perforación bajo la metodología enmarcada dentro del Project Management Institute (PMI), sin embargo, a medida que los proyectos de perforación van evolucionando y aumenta su nivel de complejidad e incertidumbre, las empresas van incorporando diversas metodologías y software, para potenciar su gestión como: Primavera, Prince; Project; Progia; Six Sigma; etc. Para poder dar una respuesta rápida en este ambiente complejo donde cada día van apareciendo nuevas interferencias que no fueron identificadas en un principio. El instituto de gestión de proyectos (PMI), ha incorporado su guía práctica Ágil. El enfoque ágil, ha revolucionado la manera de trabajar de los equipos, la adaptación de las organizaciones y la gestión de los procesos en los proyectos informáticos. Así surge la interrogante: ¿Podemos aplicar las metodologías agiles a otros proyectos que no sean informáticos? La gestión de la perforación diamantina: ¿Puede adaptarse a este nuevo concepto de gestión? o viéndolo de otra manera ¿qué de malo hay en gestionarlo bajo un enfoque de metodología tradicional?, trataremos de contestar estas interrogantes mediante un análisis cualitativo de los costos fijos y variables que impactan en el costo final del precio de la perforación diamantina ($/m), de un proyecto soportado por la gestión ágil. En definitiva, la aplicación de una metodología que tuvo éxito en una industria no necesariamente podría tener éxito en otra. Pero vale la pena analizarlo ya que de ello depende la generación de oportunidades que nos presenta el enfoque Ágil de la gestión de proyectos.