scholarly journals No consistent evidence for microbiota in murine placental and fetal tissues

2019 ◽  
Author(s):  
Kevin R. Theis ◽  
Roberto Romero ◽  
Jonathan M. Greenberg ◽  
Andrew D. Winters ◽  
Valeria Garcia-Flores ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Bacterial Isolate ◽  
Fetal Brain ◽  
16S Rrna Gene Sequencing ◽  
In Utero ◽  
Rrna Gene ◽  
Bacterial Cultures ◽  
Fetal Tissues ◽  
Rrna Gene Sequencing ◽  
Colonization Hypothesis

ABSTRACTThe existence of a placental microbiota and in utero colonization of the fetus has been the subject of recent debate. The objective of this study was to determine whether the placental and fetal tissues of mice harbor bacterial communities. Bacterial profiles of the placenta and fetal brain, lung, liver, and intestine were characterized through culture, qPCR, and 16S rRNA gene sequencing. These profiles were compared to those of the maternal mouth, lung, liver, uterus, cervix, vagina, and intestine, as well as to background technical controls. Positive bacterial cultures from placental and fetal tissues were rare; of the 165 total bacterial cultures of placental tissues from the 11 mice included in this study, only nine yielded at least a single colony, and five of those nine positive cultures came from a single mouse. Cultures of fetal intestinal tissues yielded just a single bacterial isolate: Staphylococcus hominis, a common skin bacterium. Bacterial loads of placental and fetal brain, lung, liver, and intestinal tissues were not higher than those of DNA contamination controls and did not yield substantive 16S rRNA gene sequencing libraries. From all placental or fetal tissues (N = 49), there was only a single bacterial isolate that came from a fetal brain sample having a bacterial load higher than that of contamination controls and that was identified in sequence-based surveys of at least one of its corresponding maternal samples. Therefore, using multiple modes of microbiologic inquiry, there was not consistent evidence of bacterial communities in the placental and fetal tissues of mice.IMPORTANCEThe prevailing paradigm in obstetrics has been the sterile womb hypothesis, which posits that fetuses are first colonized by microorganisms during the delivery process. However, some are now suggesting that fetuses are consistently colonized by microorganisms in utero by microbial communities that inhabit the placenta and intra-amniotic environment. Given the established causal role of microbial invasion of the amniotic cavity (i.e. intra-amniotic infection) in pregnancy complications, especially preterm birth, if the in utero colonization hypothesis were true, there are several aspects of current understanding that will need to be reconsidered including the magnitude of intra-amniotic microbial load required to cause disease and their potential influence on the ontogeny of the immune system. However, acceptance of the in utero colonization hypothesis is premature. Herein, we do not find consistent evidence for placental and fetal microbiota in mice using culture, qPCR, and DNA sequencing.

scholarly journals No Consistent Evidence for Microbiota in Murine Placental and Fetal Tissues

mSphere ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Kevin R. Theis ◽  
Roberto Romero ◽  
Jonathan M. Greenberg ◽  
Andrew D. Winters ◽  
Valeria Garcia-Flores ◽  
...  
Keyword(s):  
Bacterial Isolate ◽  
Fetal Brain ◽  
16S Rrna Gene Sequencing ◽  
Fetal Tissue ◽  
In Utero ◽  
Rrna Gene ◽  
Tissue Samples ◽  
Fetal Tissues ◽  
Rrna Gene Sequencing ◽  
Colonization Hypothesis

ABSTRACT The existence of a placental microbiota and in utero colonization of the fetus have been the subjects of recent debate. The objective of this study was to determine whether the placental and fetal tissues of mice harbor bacterial communities. Bacterial profiles of the placenta and fetal brain, lung, liver, and intestine samples were characterized through culture, quantitative real-time PCR (qPCR), and 16S rRNA gene sequencing. These profiles were compared to those of the maternal mouth, lung, liver, uterus, cervix, vagina, and intestine, as well as to background technical controls. Positive bacterial cultures from placental and fetal tissue samples were rare; of the 165 total bacterial cultures of placental tissue samples from the 11 mice included in this study, only nine yielded at least a single colony, and five of those nine positive cultures came from a single mouse. Cultures of fetal intestinal tissue samples yielded just a single bacterial isolate, Staphylococcus hominis, a common skin bacterium. Bacterial loads of placental and fetal brain, lung, liver, and intestinal tissues were not higher than those of DNA contamination controls and did not yield substantive 16S rRNA gene sequencing libraries. From all placental or fetal tissue samples (n = 51), there was only a single bacterial isolate that came from a fetal brain sample having a bacterial load higher than that of contamination controls and that was identified in sequence-based surveys of at least one of its corresponding maternal samples. Therefore, using multiple modes of microbiological inquiry, there was not consistent evidence of bacterial communities in the placental and fetal tissues of mice. IMPORTANCE The prevailing paradigm in obstetrics has been the sterile womb hypothesis, which posits that fetuses are first colonized by microorganisms during the delivery process. However, some are now suggesting that fetuses are consistently colonized in utero by microorganisms from microbial communities that inhabit the placenta and intra-amniotic environment. Given the established causal role of microbial invasion of the amniotic cavity (i.e., intra-amniotic infection) in pregnancy complications, especially preterm birth, if the in utero colonization hypothesis were true, there are several aspects of current understanding that will need to be reconsidered; these aspects include the magnitude of intra-amniotic microbial load required to cause disease and its potential influence on the ontogeny of the immune system. However, acceptance of the in utero colonization hypothesis is premature. Herein, we do not find consistent evidence for placental and fetal microbiota in mice using culture, qPCR, and DNA sequencing.

scholarly journals Interplay between Fungal Infection and Bacterial Associates in the Wax Moth Galleria mellonella under Different Temperature Conditions

2020 ◽  
Vol 6 (3) ◽  
pp. 170
Author(s):  
Vadim Yu Kryukov ◽  
Elena Kosman ◽  
Oksana Tomilova ◽  
Olga Polenogova ◽  
Ulyana Rotskaya ◽  
...  
Keyword(s):  
Fungal Infection ◽  
Bacterial Communities ◽  
Galleria Mellonella ◽  
Fungal Growth ◽  
16S Rrna Gene Sequencing ◽  
Illumina Miseq ◽  
Rrna Gene ◽  
Cultivable Bacteria ◽  
Stress Related Genes ◽  
Rrna Gene Sequencing

Various insect bacterial associates are involved in pathogeneses caused by entomopathogenic fungi. The outcome of infection (fungal growth or decomposition) may depend on environmental factors such as temperature. The aim of this study was to analyze the bacterial communities and immune response of Galleria mellonella larvae injected with Cordyceps militaris and incubated at 15 °C and 25 °C. We examined changes in the bacterial CFUs, bacterial communities (Illumina MiSeq 16S rRNA gene sequencing) and expression of immune, apoptosis, ROS and stress-related genes (qPCR) in larval tissues in response to fungal infection at the mentioned temperatures. Increased survival of larvae after C. militaris injection was observed at 25 °C, although more frequent episodes of spontaneous bacteriosis were observed at this temperature compared to 15 °C. We revealed an increase in the abundance of enterococci and enterobacteria in the midgut and hemolymph in response to infection at 25 °C, which was not observed at 15 °C. Antifungal peptide genes showed the highest expression at 25 °C, while antibacterial peptides and inhibitor of apoptosis genes were strongly expressed at 15 °C. Cultivable bacteria significantly suppressed the growth of C. militaris. We suggest that fungi such as C. militaris may need low temperatures to avoid competition with host bacterial associates.

Effect of bamboo vinegar powder as an antibiotic alternative on the digesta bacteria communities of finishing pigs

2018 ◽  
Vol 64 (10) ◽  
pp. 732-743
Author(s):  
Huan Qu ◽  
Yanjie Huang ◽  
Yinghao Shi ◽  
Ying Liu ◽  
Shenglong Wu ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Metabolic Pathways ◽  
Growth And Development ◽  
Intestinal Microflora ◽  
Gene Sequencing ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Finishing Pigs ◽  
Rrna Gene Sequencing ◽  
Bacteria Communities

This study investigated the use for bamboo vinegar powder as an antibiotic alternative in the diet of growing–finishing pigs by examining their digestive bacterial communities. Forty-five Duroc × Landrace × Yorkshire growing–finishing pigs were randomly allocated to five diet groups: 0%, 0.5%, 1.0%, or 1.5% bamboo vinegar levels and antibiotics. After 37 days, the digesta in duodenum of four pigs from each treatment were analyzed for their bacterial community compositions using 16S rRNA gene sequencing. The addition of 1.5% bamboo vinegar powder had an effect on the intestinal microflora most similar to that of antibiotics, indicating its potential to promote the growth and development of finishing pigs. We also found the 1.5% bamboo vinegar powder group to have an increased abundance of Firmicutes/Bacteroidetes compared with the other bamboo vinegar powder groups, which may enhance the ability of the host to absorb food energy and store more body fat. Additionally, the effects of bamboo vinegar powder on promoting the abundances of Lactobacillus and Thalassospira and on inhibiting Streptococcus and Prevotella growth revealed it may play an important role in animal production. Moreover, functional predictions of microbes via PICRUSt indicated that feed supplemented with 1.5% bamboo vinegar powder could promote many vital metabolic pathways.

scholarly journals Loss of bacterial diversity in the sinuses is associated with lower smell discrimination scores

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Kristi Biswas ◽  
Brett Wagner Mackenzie ◽  
Charlotte Ballauf ◽  
Julia Draf ◽  
Richard G. Douglas ◽  
...  
Keyword(s):  
Bacterial Diversity ◽  
Bacterial Communities ◽  
Gene Sequencing ◽  
16S Rrna Gene Sequencing ◽  
Olfactory Dysfunction ◽  
Rrna Gene ◽  
Olfactory Loss ◽  
Olfactory Impairment ◽  
Rrna Gene Sequencing ◽  
Normal Sense

Abstract Olfactory impairment affects ~ 20% of the population and has been linked to various serious disorders. Microbes in the nasal cavity play a key role in priming the physiology of the olfactory epithelium and maintaining a normal sense of smell by the host. The aim of this study was to explore the link between olfactory dysfunction and nasal bacterial communities. A total of 162 subjects were recruited for this study from a specialized olfactory dysfunction clinic and placed into one of three groups: anosmia, hyposmia or normosmia. Swabs from the nasal middle meatus were collected from each subject then processed for bacterial 16S rRNA gene sequencing. No overall differences in bacterial diversity or composition were observed between the three cohorts in this study. However, the relative abundances of Corynebacterium spp. and Streptococcus spp. were significantly (p < 0.05) different in subjects with olfactory loss. Furthermore, subjects with deficiencies in discriminating between smells (based on discrimination scores) had a lower bacterial diversity (Simpson’s evenness p < 0.05). While these results are preliminary in nature, potential bacterial biomarkers for olfactory loss were identified. These findings need to be further validated and biologically tested in animal models.

scholarly journals Changes of Bacterial Communities in Response to Prolonged Hydrodynamic Disturbances in the Eutrophic Water-Sediment Systems

2019 ◽  
Vol 16 (20) ◽  
pp. 3868
Author(s):  
Haomiao Cheng ◽  
Ling Cheng ◽  
Liang Wang ◽  
Tengyi Zhu ◽  
Wei Cai ◽  
...  
Keyword(s):  
Relative Abundance ◽  
Bacterial Communities ◽  
16S Rrna Gene Sequencing ◽  
Aquatic Environments ◽  
Rrna Gene ◽  
Evolutionary Trend ◽  
Ecological Evaluation ◽  
Eutrophic Water ◽  
Rrna Gene Sequencing ◽  
Opposite Tendency

The effects of hydrodynamic disturbances on the bacterial communities in eutrophic aquatic environments remain poorly understood, despite their importance to ecological evaluation and remediation. This study investigated the evolution of bacterial communities in the water–sediment systems under the influence of three typical velocity conditions with the timescale of 5 weeks. The results demonstrated that higher bacterial diversity and notable differences were detected in sediment compared to water using the 16S rRNA gene sequencing. The phyla Firmicutes and γ-Proteobacteria survived better in both water and sediment under stronger water disturbances. Their relative abundance peaked at 36.0%, 33.2% in water and 38.0%, 43.6% in sediment, respectively, while the phylum Actinobacteria in water had the opposite tendency. Its relative abundance grew rapidly in static control (SC) and peaked at 44.8%, and it almost disappeared in disturbance conditions. These phenomena were caused by the proliferation of genus Exiguobacterium (belonging to Firmicutes), Citrobacter, Acinetobacter, Pseudomonas (belonging to γ-Proteobacteria), and hgcI_clade (belonging to Actinobacteria). The nonmetric multidimensional scaling (NMDS) and Venn analysis also revealed significantly different evolutionary trend in the three water-sediment systems. It was most likely caused by the changes of geochemical characteristics (dissolved oxygen (DO) and nutrients). This kind of study can provide helpful information for ecological assessment and remediation strategy in eutrophic aquatic environments.

scholarly journals The Gut Microbial Community of Antarctic Fish Detected by 16S rRNA Gene Sequence Analysis

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Wei Song ◽  
Lingzhi Li ◽  
Hongliang Huang ◽  
Keji Jiang ◽  
Fengying Zhang ◽  
...  
Keyword(s):  
Microbial Community ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Bacterial Communities ◽  
Antarctic Fish ◽  
16S Rrna Gene Sequencing ◽  
Physiological Characteristics ◽  
Rrna Gene ◽  
Rrna Gene Sequencing ◽  
Gut Microbial Community

Intestinal bacterial communities are highly relevant to the digestion, nutrition, growth, reproduction, and a range of fitness in fish, but little is known about the gut microbial community in Antarctic fish. In this study, the composition of intestinal microbial community in four species of Antarctic fish was detected based on 16S rRNA gene sequencing. As a result, 1 004 639 sequences were obtained from 13 samples identified into 36 phyla and 804 genera, in which Proteobacteria, Actinobacteria, Firmicutes, Thermi, and Bacteroidetes were the dominant phyla, and Rhodococcus, Thermus, Acinetobacter, Propionibacterium, Streptococcus, and Mycoplasma were the dominant genera. The number of common OTUs (operational taxonomic units) varied from 346 to 768, while unique OTUs varied from 84 to 694 in the four species of Antarctic fish. Moreover, intestinal bacterial communities in individuals of each species were not really similar, and those in the four species were not absolutely different, suggesting that bacterial communities might influence the physiological characteristics of Antarctic fish, and the common bacterial communities might contribute to the fish survival ability in extreme Antarctic environment, while the different ones were related to the living habits. All of these results could offer certain information for the future study of Antarctic fish physiological characteristics.

Analysis of Bacterial Communities by 16S rRNA Gene Sequencing in a Melon-Producing Agro-environment

2021 ◽  
Author(s):  
Eduardo Franco-Frías ◽  
Victor Mercado-Guajardo ◽  
Angel Merino-Mascorro ◽  
Janeth Pérez-Garza ◽  
Norma Heredia ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Bacterial Communities ◽  
Gene Sequencing ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Rrna Gene Sequencing

scholarly journals Dynamic changes of the fecal bacterial community in dairy cows during early lactation

AMB Express ◽  
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Shuai Huang ◽  
Shoukun Ji ◽  
Feiran Wang ◽  
Jie Huang ◽  
Gibson Maswayi Alugongo ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Bacterial Communities ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Early Lactation ◽  
Lactating Cows ◽  
Composition And Structure ◽  
Dietary Transition ◽  
Fecal Bacterial Community ◽  
Rrna Gene Sequencing

Abstract The dynamics of the community structure and composition of the dairy cow fecal bacterial communities during early lactation is unclear, therefore this study was conducted to characterize the fecal bacterial communities in dairy cows during early lactation using 16S rRNA gene sequencing. Feces were sampled from 20 healthy fresh Holstein dairy cows on day 1 (Fresh1d group) and day 14 (Fresh14d group) after calving. After calving, cows were fed the same fresh diet. The dominant phyla Firmicutes and Proteobacteria were decreased (P ≤ 0.01) with lactating progress and phyla Bacteroidetes were increased (P = 0.008) with lactating progress and dietary transition. At family level, the predominant families were Ruminococcaceae (35.23%), Lachnospiraceae (11.46%), Rikenellaceae (10.44%) and Prevotellaceae (6.89%). A total of 14 genera were different between fecal samples from Fresh1d and Fresh14d, included the predominant genera, such as Ruminococcaceae_UCG-005 (P = 0.008), Rikenellaceae_RC9_gut_group (P = 0.043) and Christensenellaceae_R-7_group (P = 0.008). All fecal bacterial communities shared members of the genera Ruminococcaceae_UCG-005, Bacteroides and Rikenellaceae_RC9_gut_group. These findings help to improve our understanding of the composition and structure of the fecal microbial community in fresh cows and may provide insight into bacterial adaptation time and dietary in lactating cows.

scholarly journals Digestive gland microbiome of Pleurobema cordatum: mesocosms induce dysbiosis

2020 ◽  
Vol 86 (4) ◽  
pp. 280-289
Author(s):  
Alison K Aceves ◽  
Paul D Johnson ◽  
Carla L Atkinson ◽  
Brian C van Ee ◽  
Stephen A Bullard ◽  
...  
Keyword(s):  
Digestive Gland ◽  
Gut Microbiome ◽  
Bacterial Communities ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Artificial Rearing ◽  
Tennessee River ◽  
Wasting Syndrome ◽  
Water And Sediment ◽  
Rrna Gene Sequencing

ABSTRACT Herein, we characterized the digestive gland (‘gut’) bacterial community (microbiome) of the Ohio pigtoe, Pleurobema cordatum (Rafinesque, 1820), using 16S rRNA gene sequencing. Two populations were compared: wild P. cordatum (n = 5) from the Tennessee River and P. cordatum (n = 9) relocated to artificial mesocosms and exposed to various thermal regimes for 2 weeks. We also characterized the bacterial communities from the habitat (water and sediment) of these wild and mesocosm-held populations. The gut microbiome of wild P. cordatum was dominated by members of the bacterial phylum Tenericutes (72%). By contrast, the gut microbiome of mesocosm-held P. cordatum was dominated by members of the bacterial phylum Proteobacteria (64%). We found no temperature-associated difference in the gut microbiome of mesocosm-held P. cordatum. The bacterial communities of water and sediment from the Tennessee River were diverse and distinct from those of the studied mussels. By contrast, the bacterial communities of water and sediment in the mesocosms were dominated by Proteobacteria. These results suggest that when the studied mussels were moved into artificial rearing environments, their gut microbiome shifted to reflect that of their habitat (i.e. an increase in Proteobacteria). Moreover, the abundance of Tenericutes (also previously reported in other unionids) was reduced from 72% in wild mussels to 3% in mesocosm-held mussels. As a result, we think that mesocosm-held P. cordatum became dysbiotic, which could explain the observed wasting syndrome and associated trickling mortalities in captive P. cordatum.

scholarly journals 1207. Combining standard bacterial vaginosis treatment with cystine uptake inhibitors to block growth of Lactobacillus iners is a potential a target for shifting the cervicovaginal microbiota towards health-associated Lactobacillus crispatus-dominant communities

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S625-S626
Author(s):  
Seth M Bloom ◽  
Nomfuneko A Mafunda ◽  
Benjamin M Woolston ◽  
Matthew R Hayward ◽  
Josephine F Frempong ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Bacterial Communities ◽  
Gene Sequencing ◽  
16S Rrna Gene Sequencing ◽  
Lactobacillus Species ◽  
Rrna Gene ◽  
Rrna Gene Sequencing ◽  
Media Condition ◽  
Mrs Broth

Abstract Background Cervicovaginal microbiota domination by Lactobacillus crispatus is associated with beneficial health outcomes, whereas L. iners dominance has more adverse associations. However bacterial vaginosis (BV) treatment with metronidazole (MTZ) typically leads to domination by L. iners rather than L. crispatus. L. iners differs from other lactobacilli by its inability to grow in MRS media. We hypothesized that exploring this growth difference would identify targets for selective L. iners inhibition. Methods Bacteria were grown anaerobically. Nutrient uptake and metabolism were assessed using UPLC-MS/MS and isotopically labeled substrates. Bacterial genome annotation employed Prodigal, Roary, and EggNOG. Competition experiments with mock mixed communities were analyzed by 16S rRNA gene sequencing. We confirmed result generalizability using a diverse collection of South African and North American strains and genomes. Results Supplementing MRS broth with L-cysteine (Cys) or L-cystine permitted robust L. iners growth, while L. crispatus grew without Cys supplementation. Despite their different growth requirements, neither species could synthesize Cys via canonical pathways. Adding the cystine uptake inhibitors S-methyl-L-cysteine (SMC, Fig 1) or seleno-DL-cystine (SDLC) blocked growth of L. iners but not other lactobacilli, suggesting L. iners lacks mechanisms other lactobacilli use to exploit complex exogenous Cys sources. Notably, cydABCD, an operon with Cys/glutathione transport and redox homeostasis activities, is absent from L. iners but present in non-iners Lactobacillus species. Consistent with possible roles for cydABCD in explaining the observed phenotypes, (1) L. iners failed to take up exogenous glutathione and (2) supplementing MRS with reducing agents permitted L. iners growth, which could be blocked by SMC or SDLC. In growth competitions testing L. iners and L. crispatus within mock BV-like communities, SMC plus MTZ outperformed MTZ alone in promoting L. crispatus dominance (Figs 2&3). Figure 1: S-methyl-L-cysteine (SMC) selectively blocks growth of L. iners but not other cervicovaginal Lactobacillus species in cysteine-supplemented MRS broth. Growth was measured by optical density and inhibition calculated relative to Cys-supplemented no-inhibitor control during exponential growth. Values displayed are median (+/- maximum/minimum) for 3 replicates from a single experiment. In all panels, representative data are shown from 1 of &gt;=2 independent experiments for each bacterial strain and media condition. Results are representative of multiple strains for L. iners (n = 16), L. crispatus (n = 7), and L. jensenii (n = 2). Figure 2: Relative abundance of L. crispatus, L. iners, or various BV-associated bacteria in mock bacterial communities grown in rich, non-selective media with or without metronidazole (MTZ) and/or SMC. Relative abundance was determined by bacterial 16S rRNA gene sequencing. Data are shown for three representative mock communities with 5 replicates per media condition. Figure 3: Ratio of L. crispatus to other species in the mock bacterial communities depicted in Figure 2. Statistical significance determined via 1-way ANOVA of log10-transformed ratios with post-hoc Tukey test; selected pairwise comparisons are shown (***, p &lt; 0.001). Conclusion L. iners has unique requirements for exogenous cysteine/cystine or a reduced environment for growth. Targeting cystine uptake to inhibit L. iners is a potential strategy for shifting cervicovaginal microbiota towards L. crispatus-dominant communities. Disclosures Douglas S. Kwon, MD, PhD, Day Zero Diagnostics (Consultant, Shareholder, Other Financial or Material Support, co-founder)

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