Genetic Influences of the Microbiota on the Life Span of Drosophila melanogaster.

To better understand how associated microorganisms ("microbiota") influence organismal aging, we focused on the model organism Drosophila melanogaster We conducted a metagenome-wide association (MGWA) as a screen to identify bacterial genes associated with variation in the D. melanogaster life span. The results of the MGWA predicted that bacterial cysteine and methionine metabolism genes influence fruit fly longevity. A mutant analysis, in which flies were inoculated with Escherichia coli strains bearing mutations in various methionine cycle genes, confirmed a role for some methionine cycle genes in extending or shortening fruit fly life span. Initially, we predicted these genes might influence longevity by mimicking or opposing methionine restriction, an established mechanism for life span extension in fruit flies. However, follow-up transcriptome sequencing (RNA-seq) and metabolomic experiments were generally inconsistent with this conclusion and instead implicated glucose and vitamin B6 metabolism in these influences. We then tested if bacteria could influence life span through methionine restriction using a different set of bacterial strains. Flies reared with a bacterial strain that ectopically expressed bacterial transsulfuration genes and lowered the methionine content of the fly diet also extended female D. melanogaster life span. Taken together, the microbial influences shown here overlap with established host genetic mechanisms for aging and therefore suggest overlapping roles for host and microbial metabolism genes in organismal aging.IMPORTANCE Associated microorganisms ("microbiota") are intimately connected to the behavior and physiology of their animal hosts, and defining the mechanisms of these interactions is an urgent imperative. This study focuses on how microorganisms influence the life span of a model host, the fruit fly Drosophila melanogaster First, we performed a screen that suggested a strong influence of bacterial methionine metabolism on host life span. Follow-up analyses of gene expression and metabolite abundance identified stronger roles for vitamin B6 and glucose than methionine metabolism among the tested mutants, possibly suggesting a more limited role for bacterial methionine metabolism genes in host life span effects. In a parallel set of experiments, we created a distinct bacterial strain that expressed life span-extending methionine metabolism genes and showed that this strain can extend fly life span. Therefore, this work identifies specific bacterial genes that influence host life span, including in ways that are consistent with the expectations of methionine restriction.

The microbiota influences the Drosophila melanogaster life history strategy.

Organisms are locally adapted when members of a population have a fitness advantage in one location relative to conspecifics in other geographies. For example, across latitudinal gradients, some organisms may trade off between traits that maximize fitness components in one, but not both, of somatic maintenance or reproductive output. Latitudinal gradients in life history strategies are traditionally attributed to environmental selection on an animal's genotype, without any consideration of the possible impact of associated microorganisms ("microbiota") on life history traits. Here, we show in Drosophila melanogaster, a key model for studying local adaptation and life history strategy, that excluding the microbiota from definitions of local adaptation is a major shortfall. First, we reveal that an isogenic fly line reared with different bacteria varies the investment in early reproduction versus somatic maintenance. Next, we show that in wild fruit flies, the abundance of these same bacteria was correlated with the latitude and life history strategy of the flies, suggesting geographic specificity of the microbiota composition. Variation in microbiota composition of locally adapted D. melanogaster could be attributed to both the wild environment and host genetic selection. Finally, by eliminating or manipulating the microbiota of fly lines collected across a latitudinal gradient, we reveal that host genotype contributes to latitude-specific life history traits independent of the microbiota and that variation in the microbiota can suppress or reverse the differences between locally adapted fly lines. Together, these findings establish the microbiota composition of a model animal as an essential consideration in local adaptation.

Draft Genome Sequence of Lactobacillus paracasei DmW181, a Bacterium Isolated from Wild Drosophila.

The draft genome sequence of Lactobacillus paracasei DmW181, an anaerobic bacterium isolate from wild Drosophila flies, is reported here. Strain DmW181 possesses genes for sialic acid and mannose metabolism. The assembled genome is 3,201,429 bp, with 3,454 predicted genes.

Genome Sequence of Leuconostoc citreum DmW_111, Isolated from Wild Drosophila.

Isolates of the lactic acid bacterium Leuconostoc citreum are a major part of fermentation processes, especially in Korean kimchi. Here, we present the genome of L. citreum DmW_111, isolated from wild Drosophila melanogaster; analysis of this genome will expand the diversity of genome sequences for non-Lactobacillus spp. isolated from D. melanogaster.

Genome Sequence of Weissella cibaria DmW_103, Isolated from Wild Drosophila.

Lactic acid bacteria are commonly associated with Drosophila spp. Here, we report on the isolation of a strain of Weissella cibaria and the sequencing, assembly, and annotation of its genome. A total of 35 contigs were generated, with 2,349 coding sequences found.

Fibromyalgia syndrome: considerations for dental hygienists.

PURPOSE: Fibromyalgia syndrome (FMS) is a neurosensory disorder characterized by widespread musculoskeletal pain. Typically persistent fatigue, depression, limb stiffness, non-refreshing sleep and cognitive deficiencies are also experienced. Oral symptoms and pain are common, requiring adaptations in patient management strategies and treatment interventions. Appropriate dental hygiene care of patients suffering with this disorder is contingent upon an understanding of disease epidemiology, pathophysiology, clinical characteristics, oral signs and symptoms, as well as treatment approaches. With this information dental hygienists will be better prepared to provide appropriate and effective treatment to patients with FMS.

The effect of food label cues on perceptions of quality and purchase intentions among high-involvement consumers with varying levels of nutrition knowledge.

OBJECTIVE: To determine whether differences in nutrition knowledge affected how women (a high-involvement group) interpreted intrinsic cues (ingredient list) and extrinsic cues ("all natural" label) on food labels. METHODS: A 2 (intrinsic cue) × 2 (extrinsic cue) × 2 (nutrition knowledge expert vs novice) within-subject factorial design was used. Participants were 106 female college students (61 experts, 45 novices). Dependent variables were perception of product quality and purchase intention. RESULTS: As predicted by the elaboration likelihood model, experts used central route processing to scrutinize intrinsic cues and make judgments about food products. Novices used peripheral route processing to make simple inferences about the extrinsic cues in labels. CONCLUSIONS AND IMPLICATIONS: Consumers' levels of nutrition knowledge influenced their ability to process food labels. The United States Food and Drug Administration should regulate the "all natural" food label, because this claim is likely to mislead most consumers.