A genome-scale metabolic reconstruction of Lysinibacillus sphaericus unveils unexploited biotechnological potentials.

The toxic lineage (TL) of Lysinibacillus sphaericus has been extensively studied because of its potential biotechnological applications in biocontrol of mosquitoes and bioremediation of toxic metals. We previously proposed that L. sphaericus TL should be considered as a novel species based on a comparative genomic analysis. In the current work, we constructed the first manually curated metabolic reconstruction for this species on the basis of the available genomes. We elucidated the central metabolism of the proposed species and, beyond confirming the reported experimental evidence with genomic a support, we found insights to propose novel applications and traits to be considered in further studies. The strains belonging to this lineage exhibit a broad repertory of genes encoding insecticidal factors, some of them remain uncharacterized. These strains exhibit other unexploited biotechnological important traits, such as lactonases (quorum quenching), toxic metal resistance, and potential for aromatic compound degradation. In summary, this study provides a guideline for further research aimed to implement this organism in biocontrol and bioremediation. Similarly, we highlighted the unanswered questions to be responded in order to gain a deeper understanding of the L. sphaericus TL biology.

Comparative genomics reveals Lysinibacillus sphaericus group comprises a novel species.

BACKGROUND: Early in the 1990s, it was recognized that Lysinibacillus sphaericus, one of the most popular and effective entomopathogenic bacteria, was a highly heterogeneous group. Many authors have even proposed it comprises more than one species, but the lack of phenotypic traits that guarantee an accurate differentiation has not allowed this issue to be clarified. Now that genomic technologies are rapidly advancing, it is possible to address the problem from a whole genome perspective, getting insights into the phylogeny, evolutive history and biology itself. RESULTS: The genome of the Colombian strain L. sphaericus OT4b.49 was sequenced, assembled and annotated, obtaining 3 chromosomal contigs and no evidence of plasmids. Using these sequences and the 13 other L. sphaericus genomes available on the NCBI database, we carried out comparative genomic analyses that included whole genome alignments, searching for mobile elements, phylogenomic metrics (TETRA, ANI and in-silico DDH) and pan-genome assessments. The results support the hypothesis about this species as a very heterogeneous group. The entomopathogenic lineage is actually a single and independent species with 3728 core genes and 2153 accessory genes, whereas each non-toxic strain seems to be a separate species, though without a clear circumscription. Toxin-encoding genes, binA, B and mtx1, 2, 3 could be acquired via horizontal gene transfer in a single evolutionary event. The non-toxic strain OT4b.31 is the most related with the type strain KCTC 3346. CONCLUSIONS: The current L. sphaericus is actually a sensu lato due to a sub-estimation of diversity accrued using traditional non-genomics based classification strategies. The toxic lineage is the most studied with regards to its larvicidal activity, which is a greatly conserved trait among these strains and thus, their differentiating feature. Further studies are needed in order to establish a univocal classification of the non-toxic strains that, according to our results, seem to be a paraphyletic group.

Complete Genome Sequence of Lysinibacillus sphaericus WHO Reference Strain 2362.

Lysinibacillus sphaericus is a species that contains strains widely used in the biological control of mosquitoes. Here, we present the complete 4.67-Mb genome of the WHO entomopathogenic reference strain L. sphaericus 2362, which is probably one of the most commercialized and studied strains. Genes coding for mosquitocidal toxin proteins were detected.

Descripción del patrón de consumo de golosinas en escolares de 5º curso de Educación Primaria de la Ciudad Autónoma de Ceuta / No disponible

Fundamentos: El consumo de golosinas es habitual enjóvenes y adolescentes, particularmente incidente en elprimer periodo de la adolescencia. Está asociado a lapatogenia de enfermedades como la caries y la obesidad.El objetivo general del estudio consiste en establecer elpatrón de consumo de golosinas de los escolares de 5ºde Primaria en la Ciudad Autónoma de Ceuta.Material y método: Se realizó un estudio transversal descriptivosobre una muestra representativa de 293 sujetos,mediante un cuestionario diseñado ad hoc. Los resultadosse analizan agrupados en nueve dimensiones:frecuencia y cantidad, momento de consumo, modo deingesta, lugar de compra y de consumo, existencia deconsumo compartido, criterios de elección, gasto diario,conocimiento del daño que puede provocar y existenciade limitación ajena o propia.Conclusiones: Este consumo es habitual y repartido en elhorario de tarde, por lo que aumenta su poder cariogénico.Se realiza en solitario en una tercera parte de los sujetos,reflejando un cierto grado de compulsión en el hábito deconsumo. Tienen conocimiento sobre la insalubridad delconsumo de golosinas pero, contradictoriamente, sonconsumidores habituales y, además, lo autoevalúan comonormal. No existe un excesivo control familiar, reflejandoun cierto conformismo con este consumo(AU)

Background: The consumption of candy is habitual foryoung people and teenagers, particularly during the firstperiod of teenage. It is associated with the pathogeny ofdiseases such as caries and obesity. The general objectiveof this research is to establish the candy consumptionpattern of 5th grade students from the Autonomous Cityof Ceuta.Methods: A transversal, descriptive study has beenrealized, with a representative sample of 293 subjects,using an ad-hoc questionnaire. Results are analysedgrouped in nine dimensions: frequency and quantity,moment of consumption, type of intake, place of purchaseand consumption, existence of shared consumption,criteria of election, daily expense, knowledge about theharm it may cause and existence of external or personalconstraints.Conclusions: Consumption is frequent and spread alongthe afternoon, enhancing its cariogenic power.Furthermore, candies are taken on their own by one thirdof the subjects, reflecting a certain degree of compulsionin the habit of candy consumption. Consumers know aboutthe unhealthiness of candy consumption but,contradictorily, they are habitual consumers and, besides,they consider it as normal. There is not an excessive familycontrol, showing a certain conformism about thisconsumption(AU)