Comparative Analysis of Ribonuclease P RNA of the Planctomycetes

The planctomycetes, order Planctomycetales, are a distinct phylum of domain Bacteria. Genes encoding the RNA portion of ribonuclease P (RNase P) of some planctomycete members were sequenced and compared with existing database planctomycete sequences. rnpB gene sequences encoding RNase P RNA were generated by a conserved primer PCR strategy for Planctomyces brasiliensis, Planctomyces limnophilus, Pirellula marina, Pirellula staleyi strain ATCC 35122, Isosphaera pallida, one other Isosphaera strain, Gemmata obscuriglobus and three other strains of the Gemmata group. These sequences were aligned against reference bacterial sequences and secondary structures of corresponding RNase P RNAs deduced by a comparative approach. P12 helices were found to be highly variable in length, as were helices P16.1 and P19, when present. RNase P RNA secondary structures of Gemmata isolates were found to have unusual features relative to other planctomycetes, including a long P9 helix and an insert in the P13 helix not found in any other member of domain Bacteria. These unique features are consistent with other unusual properties of this genus, distinguishing it from other bacteria. Phylogenetic analyses indicate that relationships between planctomycetes derived from RNase P RNA are consistent with 16S rRNA-based analyses

High ultraviolet C resistance of marine Planctomycetes

Planctomycetes are bacteria with particular characteristics such as internal membrane systems encompassing intracellular compartments, proteinaceous cell walls, cell division by yeast-like budding and large genomes. These bacteria inhabit a wide range of habitats, including marine ecosystems, in which ultra-violet radiation has a potential harmful impact in living organisms. To evaluate the effect of ultra-violet C on the genome of several marine strains of Planctomycetes, we developed an easy and fast DNA diffusion assay in which the cell wall was degraded with papain, the wall-free cells were embedded in an agarose microgel and lysed. The presence of double strand breaks and unwinding by single strand breaks allow DNA diffusion, which is visible as a halo upon DNA staining. The number of cells presenting DNA diffusion correlated with the dose of ultra-violet C or hydrogen peroxide. From DNA damage and viability experiments, we found evidence indicating that some strains of Planctomycetes are significantly resistant to ultra-violet C radiation, showing lower sensitivity than the known resistant Arthrobacter sp. The more resistant strains were those phylogenetically closer to Rhodopirellula baltica, suggesting that these species are adapted to habitats under the influence of ultra-violet radiation. Our results provide evidence indicating that the mechanism of resistance involves DNA damage repair and/or other DNA ultra-violet C-protective mechanism.This research was supported by the European Regional Development Fund (ERDF) through the COMPETE-Operational Competitiveness Programme and national funds through FCT-Foundation for Science and Technology, under the projects Pest-C/BIA/UI4050/2011 and PEst-C/MAR/LA0015/2013. We are grateful to Catia Moreira for helping with the extraction of the pigments.info:eu-repo/semantics/publishedVersio

Integrating a Group-Based, Early Childhood Parenting Intervention into Primary Health Care Services in Rural Bangladesh: A Cluster-Randomised Controlled Trial

BACKGROUND: Over 250 million children globally do not reach their developmental potential. We tested whether integrating a group-based, early childhood parenting program into government healthcare clinics improved children’s development, growth, and behavior. METHODS: We conducted a cluster-randomized controlled trial in 40 community clinics in the Kishorganj district of Bangladesh. We randomly assigned clinics (1:1) to deliver a group-based parenting interventions or to a comparison group that received no intervention. Participants were children aged 5–24 months, with weight-for-age z-score of ≤ −1.5 SDs of the WHO standards, living within a thirty-minute walking distance from the clinic (n = 419 intervention, 366 control). Government health staff facilitated parenting sessions in the clinic with groups of four mother/child dyads fortnightly for one year as part of their routine duties. Primary outcomes measured at baseline and endline were child development assessed using the Bayley scales, child behaviors during the test by tester ratings, and child growth. The trial is registered at ClinicalTrials.gov, NCT02208531. FINDINGS: 91% of children were tested at endline (396 intervention, 319 control). Multilevel analyses showed significant benefits of intervention to child cognition (effect size 0.85 SDs, 95% CI: 0.59, 1.11), language (0.69 SDs, 0.43, 0.94), and motor development (0.52 SDs, 0.31, 0.73), and to child behaviors during the test (ranging from 0.36 SDs, 0.14, 0.58, to 0.53 SDs, 0.35, 0.71). There were no significant effects on growth. CONCLUSION: A scalable parenting intervention, integrated into existing government health services and implemented by government health staff, led to significant benefits to child development and behavior