scholarly journals Metagenome-Wide Association of Microbial Determinants of Host Phenotype in Drosophila melanogaster

mBio ◽  
2014 ◽  
Vol 5 (5) ◽  
Author(s):  
John M. Chaston ◽  
Peter D. Newell ◽  
Angela E. Douglas
Keyword(s):  
Drosophila Melanogaster ◽  
Nutritional Status ◽  
Glucose Oxidation ◽  
Development Time ◽  
Glucose Utilization ◽  
Fat Content ◽  
Gut Bacteria ◽  
Bacterial Strains ◽  
Oxidation Pathway ◽  
Bacterial Genes

ABSTRACT Animal-associated bacteria (microbiota) affect host behaviors and physiological traits. To identify bacterial genetic determinants of microbiota-responsive host traits, we employed a metagenome-wide association (MGWA) approach in two steps. First, we measured two microbiota-responsive host traits, development time and triglyceride (TAG) content, in Drosophila melanogaster flies monoassociated with each of 41 bacterial strains. The effects of monoassociation on host traits were not confined to particular taxonomic groups. Second, we clustered protein-coding sequences of the bacteria by sequence similarity de novo and statistically associated the magnitude of the host trait with the bacterial gene contents. The animals had been monoassociated with genome-sequenced bacteria, so the metagenome content was unambiguous. This analysis showed significant effects of pyrroloquinoline quinone biosynthesis genes on development time, confirming the results of a published transposon mutagenesis screen, thereby validating the MGWA; it also identified multiple genes predicted to affect host TAG content, including extracellular glucose oxidation pathway components. To test the validity of the statistical associations, we expressed candidate genes in a strain that lacks them. Monoassociation with bacteria that ectopically expressed a predicted oxidoreductase or gluconate dehydrogenase conferred reduced Drosophila TAG contents relative to the TAG contents in empty vector controls. Consistent with the prediction that glucose oxidation pathway gene expression increased bacterial glucose utilization, the glucose content of the host diet was reduced when flies were exposed to these strains. Our findings indicate that microbiota affect host nutritional status through modulation of nutrient acquisition. Together, these findings demonstrate the utility of MGWA for identifying bacterial determinants of host traits and provide mechanistic insight into how gut microbiota modulate the nutritional status of a model host. IMPORTANCE To understand how certain gut bacteria promote the health of their animal hosts, we need to identify the bacterial genes that drive these beneficial relationships. This task is challenging because the bacterial communities can vary widely among different host individuals. To overcome this difficulty, we quantified how well each of 41 bacterial species protected Drosophila fruit flies from high fat content. The genomes of the chosen bacterial strains were previously sequenced, so we could statistically associate specific bacterial genes with bacterially mediated reduction in host fat content. Bacterial genes that promote glucose utilization were strongly represented in the association, and introducing these genes into the gut bacteria was sufficient to lower the animal’s fat content. Our method is applicable to the study of many other host-microbe interactions as a way to uncover microbial genes important for host health.

Glucose utilization by sheep embryos derived in vivo and in vitro

1991 ◽  
Vol 3 (5) ◽  
pp. 571 ◽  
Author(s):  
JG Thompson ◽  
AC Simpson ◽  
PA Pugh ◽  
RW Wright ◽  
HR Tervit
Keyword(s):  
Glucose Oxidation ◽  
Glucose Utilization ◽  
Tricarboxylic Acid Cycle ◽  
Tricarboxylic Acid ◽  
Cell Stage ◽  
Glycolytic Activity ◽  
Total Utilization ◽  
Oxidation Of Glucose

Embryos were collected from superovulated donors at various intervals from onset of oestrus, ranging from Day 1.5 to Day 6. In addition, blastocysts obtained from the culture of 1-cell embryos collected in vivo or of oocytes matured and fertilized in vitro were used to assess the effects of in vitro manipulation and culture on glucose utilization. Glycolytic activity was determined by the conversion of [5-3H]glucose to 3H2O, and oxidation of glucose was determined by the conversion of [U-14C]glucose to 14CO2. Glucose utilization increases significantly from the 8-cell stage and during compaction and blastulation. Glucose oxidation was at a relatively low level (5-12% of total utilization) compared with glycolysis. No difference was observed between the glycolytic activity of blastocysts derived from in vivo or in vitro sources. However, glucose oxidation was lower (P less than 0.05) in blastocysts derived from the culture of 1-cell embryos or from oocytes matured and fertilized in vitro. Exogenous tricarboxylic acid cycle substrates (i.e. pyruvate and lactate supplied in the medium) affected the level of glucose oxidation.

DENSITY-DEPENDENT FERTILITY SELECTION IN EXPERIMENTAL POPULATIONS OF DROSOPHILA MELANOGASTER

Genetics ◽  
1981 ◽  
Vol 98 (4) ◽  
pp. 849B-869
Author(s):  
Andrew G Clark ◽  
Marcus W Feldman
Keyword(s):  
Drosophila Melanogaster ◽  
Development Time ◽  
Wing Length ◽  
Larval Density ◽  
High Density ◽  
Density Dependent ◽  
Resource Limited ◽  
Adult Body ◽  
Adult Body Weight ◽  
Mutant Lines

ABSTRACT The effects of larval density on components of fertility fitness were investigated with two mutant lines of Drosophila melanogaster. The differences in adult body weight, wing length, larval survivorship and development time verified that flies reared at high density were resource limited. Experimental results indicate that: (1) relative fecundities of both sexes show density-dependent effects, (2) there is a strong density effect on male and female mating success, and (3) in general, there is a reduction in fecundity differences between genotypes at high density. These results imply that it may be important to consider fertility in models of density-dependent natural selection.

scholarly journals Viral route of infection determines the effect of Drosophila melanogaster gut bacteria on host resistance and tolerance to disease

2021 ◽  
Author(s):  
Miguel Landum ◽  
Marta Salvado Silva ◽  
Nelson Martins ◽  
Luís Teixeira
Keyword(s):  
Drosophila Melanogaster ◽  
Viral Infections ◽  
Systemic Infection ◽  
Lactobacillus Brevis ◽  
Gut Bacteria ◽  
Associated Bacteria ◽  
Germ Free ◽  
Viral Loads ◽  
Route Of Infection ◽  
The Impact

AbstractThe microbial community interacting with a host can modulate the outcome of pathogenic infections. For instance, Wolbachia, one of the most prevalent invertebrate endosymbionts, strongly increases resistance of Drosophila melanogaster and other insect hosts, to many RNA viruses. D. melanogaster is also in continuous association with gut bacteria, whose role in antiviral immunity is poorly characterized. Here we asked how gut-colonizing bacteria impact viral titres and host survival, and how these interact with route of infection or Wolbachia presence. We compared germ-free flies and flies associated with two gut bacteria species recently isolated from wild flies (Acetobacter thailandicus and Lactobacillus brevis). We found that Wolbachia-conferred protection to both DCV or FHV is not affected by the presence or absence of these gut bacteria. Flies carrying A. thailandicus have lower DCV loads than germ-free flies, upon systemic infection, but reduced survival, indicating that these bacteria increase resistance to virus and decrease disease tolerance. Association with L. brevis, alone or in combination with A. thailandicus, did not lead to changes in survival to systemic infection. In contrast to the effect on systemic infection, we did not observe an impact of these bacteria on survival or viral loads after oral infection. Overall, the impact of gut-associated bacteria in resistance and tolerance to viruses was mild, when compared with Wolbachia. These results indicate that the effect of gut-associated bacteria to different viral infections, and different routes of infection, is complex and understanding it requires a detailed characterization of several parameters of infection.

scholarly journals Drug resistant gut bacteria mimic a host mechanism for anticancer drug clearance

2019 ◽  
Author(s):  
Peter Spanogiannopoulos ◽  
Patrick H. Bradley ◽  
Jonathan Melamed ◽  
Ysabella Noelle Amora Malig ◽  
Kathy N. Lam ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Drug Disposition ◽  
Transcriptional Profiling ◽  
Drug Efficacy ◽  
Drug Clearance ◽  
Gut Bacteria ◽  
Resistant Bacteria ◽  
Drug Resistant ◽  
Bacterial Strains

Microbiome surveys indicate that pharmaceuticals are the top predictor of inter-individual variations in gut microbial community structure1, consistent with in vitro evidence that non-antibiotic (i.e. host-targeted) drugs inhibit gut bacterial growth2and are subject to extensive metabolism by the gut microbiome3,4. In oncology, bacterial metabolism has been implicated in both drug efficacy5,6and toxicity7,8; however, the degree to which bacterial sensitivity and metabolism can be driven by conserved pathways also found in mammalian cells remains poorly understood. Here, we show that anticancer fluoropyrimidine drugs broadly inhibit the growth of diverse gut bacterial strains. Media supplementation, transcriptional profiling (RNA-seq), and bacterial genetics implicated pyrimidine metabolism as a key target in bacteria, as in mammalian cells. Drug resistant bacteria metabolized 5FU to its inactive metabolite dihydrofluorouracil (DHFU) mimicking the major host pathway for drug clearance. Functional orthologs of the bacterial operon responsible (preTA) are widespread across human gut bacteria from the Firmicutes and Proteobacteria phyla. The observed conservation of both the targets and pathways for metabolism of therapeutics across domains highlights the need to distinguish the relative contributions of human and microbial cells to drug disposition9, efficacy, and side effect profiles.

Quantitative aspects of glucose metabolism in pregnant and nonpregnant sheep

1963 ◽  
Vol 204 (1) ◽  
pp. 147-152 ◽  
Author(s):  
E. N. Bergman
Keyword(s):  
Glucose Oxidation ◽  
Glucose Utilization ◽  
The Body ◽  
Glucose Turnover ◽  
Turnover Rates ◽  
Pregnant Sheep ◽  
The Mean ◽  
Total Glucose ◽  
Mean Glucose ◽  
Pool Sizes

Labeled glucose was infused into four groups of ewes: nonpregnant fed; nonpregnant fasted; twin-pregnant fed; and twin-pregnant hypoglycemic and ketonemic. Mean glucose pool sizes were 157 and 127 mg/kg in nonpregnant and pregnant ewes, respectively, with decreased values in both fasting and hypoglycemia. Nonpregnant animals had glucose turnover rates averaging 4.0 g/hr (0.22 g/hr·kg3/4) when fed and only 2.7 g/hr (0.15 g/hr·kg3/4) after fasting. These values were only 60–80% of that of pregnant sheep, implying that glucose utilization due to twin-pregnancy was 20–40% of the total. The mean glucose space was about 27% of the body weight, indicating predominantly extracellular distribution of glucose even in hypoglycemia. In all animals about 8–10% of the exhaled CO2 was found to be derived from glucose oxidation and about one-third of the total glucose turnover was used for CO2 production. Comparisons of these data to values obtained from other mammals indicated further that there is a lower rate of glucose oxidation and metabolism in ruminants.

scholarly journals Evolution of reduced pre-adult viability and larval growth rate in laboratory populations of Drosophila melanogaster selected for shorter development time

2000 ◽  
Vol 76 (3) ◽  
pp. 249-259 ◽  
Author(s):  
N. G. PRASAD ◽  
MALLIKARJUN SHAKARAD ◽  
VISHAL M. GOHIL ◽  
V. SHEEBA ◽  
M. RAJAMANI ◽  
...  
Keyword(s):  
Growth Rate ◽  
Drosophila Melanogaster ◽  
Development Time ◽  
Larval Growth ◽  
Dry Weight ◽  
Relative Reduction ◽  
Larval Growth Rate ◽  
Laboratory Populations ◽  
The Difference ◽  
Faster Development

Four large (n > 1000) populations of Drosophila melanogaster, derived from control populations maintained on a 3 week discrete generation cycle, were subjected to selection for fast development and early reproduction. Egg to eclosion survivorship and development time and dry weight at eclosion were monitored every 10 generations. Over 70 generations of selection, development time in the selected populations decreased by approximately 36 h relative to controls, a 20% decline. The difference in male and female development time was also reduced in the selected populations. Flies from the selected populations were increasingly lighter at eclosion than controls, with the reduction in dry weight at eclosion over 70 generations of selection being approximately 45% in males and 39% in females. Larval growth rate (dry weight at eclosion/development time) was also reduced in the selected lines over 70 generations, relative to controls, by approximately 32% in males and 24% in females. However, part of this relative reduction was due to an increase in growth rate of the controls populations, presumably an expression of adaptation to conditions in our laboratory. After 50 generations of selection had elapsed, a considerable and increasing pre- adult viability cost to faster development became apparent, with viability in the selected populations being about 22% less than that of controls at generation 70 of selection.

Components of Genetic Variation Associated with Second and Third Chromosome Gene Arrangements in Drosophila melanogaster

Genetics ◽  
1987 ◽  
Vol 116 (1) ◽  
pp. 87-97
Author(s):  
James A Ferrari
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Variation ◽  
Low Temperature ◽  
Interaction Effect ◽  
Quantitative Traits ◽  
Development Time ◽  
Gene Arrangement ◽  
Optimal Conditions ◽  
Experimental Conditions ◽  
Chromosome Gene

ABSTRACT The effects of naturally occuring combinations of second and third chromosome gene arrangements of Drosophila melanogaster on two quantitative traits were partitioned into parameters of additive, dominance and interaction components of genetic variation. Development time and preadult survival of the gene arrangement genotypes were measured under four experimental conditions. Gene arrangement effects, when significant, were predominantly additive under all conditions. Experimental conditions, however, did influence gene arrangement effects. A second chromosome effect on development time was detected when amount of food or temperature was reduced, but not under optimal conditions. A third chromosome additive effect on development was observed under all experimental conditions. A consistent interaction effect between second and third chromosome gene arrangements was detected only at low temperature. Gene arrangement effects on survival were not as consistent as for development time, but also depended on experimental conditions.

Sign in / Sign up

Export Citation Format

Share Document