Characterization of the diversity of rhizosphere fluorescent pseudomonads populations with lipoproteine (OPRI) gene and siderphore polymorphism

International audienc

After the storm—Perspectives on the taxonomy of Lactobacillaceae

In 2020, a taxonomic reorganization of the lactic acid bacteria reclassified over 300 species in 7 genera and 2 families into one family, the Lactobacillaceae, with 31 genera including 23 new genera to include organisms formerly classified as Lactobacillus species. This communication aims to provide a debrief on the taxonomic reorganization of lactobacilli to identify shortcomings in the proposed taxonomic framework, and to outline perspectives and opportunities provided by the current taxonomy of the Lactobacillaceae. The current taxonomy of lactobacilli not only necessitates becoming familiar with 23 new genus names but also provides substantial new opportunities in scientific discovery and regulatory approval of these organisms. First, description of new species in the Lactobacillaceae is facilitated and a solid framework for description of novel genera is provided. Second, the current taxonomy greatly enhances the resolution of genus-level sequencing approaches (e.g., 16S rRNA–based metagenomics) when identifying the composition and function of microbial communities. Third, the current taxonomy greatly facilitates the formulation of hypotheses linking phylogeny to metabolism and ecology of lactobacilli

Bereavement

status: publishe

Wet combing for head lice: feasibility in mass screening, treatment preference and outcome

There is no scientific consensus on the best way to control head louse infestation in schoolchildren. A study was conducted to test the feasibility and acceptability of a screening campaign by wet combing and a community approach to head-louse control with home visits, and to explore parents' treatment preferences and treatment outcomes. A non-controlled intervention (advice on treatment options offered to all positive children) was nested within an epidemiological prevalence study. All children in three primary schools in Ghent, Belgium, were invited to take part in screening by wet combing (n=677, 3-11 years). Positive children were offered structural treatment advice, a home visit on day 7, and a check by wet combing on day 14. 83% of the children were screened. The prevalence of active infestation (living moving lice) was 13.0% in school 1 and 19.5% in school 3. In school 2, prevalence of signs of active and past infestation was 40.7%. A home visit was made to 58% of the positive children. 85% of the positive children were screened again on day 14. Wet combing was the most widely used treatment, followed by chemical treatment and a combination of the two. In school 1 and 3 51% were cured, and in school 2 24% became nit-free. A wet combing screening campaign and a community-oriented approach to head-louse control is feasible though resource-intensive. The prevalence of head lice was high and the cure rate was low, with either topical treatments or wet combing

Impacts of menstruation, community type, and an oral yeast probiotic on the vaginal microbiome

A healthy state of the vaginal microbiome can prevent vaginal disease and promote successful fertilization and healthy pregnancies. Little is known about the stability of the vaginal microbiome and the influence of factors such as diet and probiotics. While less explored, yeast probiotics have an interesting potential because of their immunomodulatory and pathogen inhibition capacities. In this study, we investigated the impact of the oral yeast probiotic Saccharomyces cerevisiae CNCM I-3856 on the vaginal microbiomes of 52 healthy women using 16S and internal transcribed spacer (ITS) amplicon sequencing and quantitative PCR (qPCR). The vaginal fungal loads remained low, even after oral yeast supplementation, complicating the analysis of the vaginal mycobiome. Lactobacillus crispatus and Lactobacillus iners were the most dominant species in our study population and were found to codominate in 23% of the baseline samples. Bifidobacterium, Streptococcus, and Prevotella were also frequently found. The microbiome profiles were dynamic: 69% of women showed a shift in the dominant community members at least once during the 42-day sampling period. In addition, lower Lactobacillus abundances were observed at the time points after menstruation. Higher relative abundances of Lactobacillus with more L. iners-dominated samples and a trend toward lower relative abundances of Prevotella were observed in the probiotic group, but analyses of the effects of the yeast probiotic were complicated by differences already present at the onset of the study. Thus, our findings especially highlighted that the impact of menstruation and the stratification of women based on the dominant vaginal taxa before randomization and inclusion is important for future research: while the impact of the yeast probiotic on vaginal microbiome in healthy women was limited. IMPORTANCE How to define and promote a healthy state of the vaginal microbiome is not well understood. Knowledge of which underlying factors shape the microbial community composition of the vagina and how to modulate them will contribute to vaginal disease prevention and improve fertility. Here, we found that taking the menstrual cycle into account when designing a microbiome study is highly recommended: menstruation also showed to be poses an interesting time point for intervention because of the drop in the abundance of L. crispatus. Furthermore, the early stratification of groups (e.g., placebo versus treatment) according to the dominant taxa can be of high added value since menstruation impacts vaginal taxa differently, i.e., L. iners remains stable, in contrast to L. crispatus

Fructilactobacillus lindneri LINDNERI 2020, COMB. NOV.

DESCRIPTIONOF <i>FRUCTILACTOBACILLUS LINDNERI</i> COMB. NOV. <p> <i>Fructilactobacillus lindneri</i> (lind'ne.ri. N.L. gen. n. <i>lindneri</i> of Lindner, recognizing the German bacteriologist Lindner).</p> <p> Basonym: <i>Lactobacilluslindneri</i> (Henneberg 1901); Back <i>etal</i>. 1997, 601 VL Earlierisolates were referred to as <i>Bacillus lindneri</i> or <i>Bacterium lindneri</i> [312]</p> <p>The description is provided in [312]. The genome size of the type strain is 1.44 Mbp. The mol% G+C content of DNA is 34.1.</p> <p>Isolated from spoiled beer and from wine.</p> <p> Thetypestrainis KPAT =CIP 102983 T =DSM 20690 T =JCM 11027 T =LMG 14528 T.</p> <p>Genome sequence accession number: JQBT00000000.</p> <p>16S rRNA gene accession number: X95421.</p>Published as part of <i>Zheng, Jinshui, Wittouck, Stijn, Salvetti, Elisa, Franz, Charles M. A. P., Harris, Hugh M. B., Mattarelli, Paola, O'Toole, Paul W., Pot, Bruno, Vandamme, Peter, Walter, Jens, Watanabe, Koichi, Wuyts, Sander, Felis, Giovanna E., Gänzle, Michael G. & Lebeer, Sarah, 2020, A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae, pp. 2782-2858 in International Journal of Systematic and Evolutionary Microbiology 70</i> on page 2841, DOI: 10.1099/ijsem.0.004107, <a href="http://zenodo.org/record/4730536">http://zenodo.org/record/4730536</a&gt