Publications by Colleges and Departments (MSU - Bozeman)
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Item Soil bacterial community response to cover crop introduction in a wheat-based dryland cropping system(Frontiers Media SA, 2022-11) Eberly, Jed O.; Bourgault, Maryse; Dafo, Julia M.; Yeoman, Carl J.; Wyffels, Samuel A.; Lamb, Peggy F.; Boss, Darrin L.The incorporation of cover crops into cropping systems is important for enhancing soil health in agricultural systems. Soil microbes contribute to soil health by supplying key nutrients and providing protection against plant pests, diseases, and abiotic stress. While research has demonstrated the connection between cover crops and the soil microbiology, less is known regarding the impact of cover crops on the soil microbial community in semi-arid regions of the Northern Great Plains. Our objectives were to evaluate changes in the soil bacterial community composition and community networks in wheat grown after multi-species cover crops. Cover crops were compared to continuous cropping and crop/fallow systems and the effects of cover crop termination methods were also evaluated. Cover crops consisted of a cool season multispecies mix, mid-season multispecies mix, and a warm season multispecies mix, which were grown in rotation with winter wheat. A continuous cropping (wheat/barley) and wheat/fallow system were also included along with cover crop termination by grazing, herbicide application, and haying. Cover crop treatments and termination methods had no significant impact on microbial community alpha diversity. Cover crop termination methods also had no significant impact on microbial community beta diversity. Families belonging to the phyla Actinobacteria, Bacterioidota, and Proteobacteria were more abundant in the cool season cover crop treatment compared to the warm season cover crop treatment. Co-occurrence network analysis indicated that incorporation of cool season cover crops or mid-season mixes in a wheat-based cropping system led to greater complexity and connectivity within these microbial networks compared to the other treatments which suggests these communities may be more resilient to environmental disturbances.Item Determinants of the postprandial triglyceride response to a high-fat meal in healthy overweight and obese adults(Springer Nature, 2021-09) Wilson, Stephanie M.; Maes, Adam P.; Yeoman, Carl J.; Walk, Seth T.; Miles, Mary P.Background. Dyslipidemia is a feature of impaired metabolic health in conjunction with impaired glucose metabolism and central obesity. However, the contribution of factors to postprandial lipemia in healthy but metabolically at-risk adults is not well understood. We investigated the collective contribution of several physiologic and lifestyle factors to postprandial triglyceride (TG) response to a high-fat meal in healthy, overweight and obese adults. Methods. Overweight and obese adults (n = 35) underwent a high-fat meal challenge with blood sampled at fasting and hourly in the 4-hour postprandial period after a breakfast containing 50 g fat. Incremental area under the curve (iAUC) and postprandial magnitude for TG were calculated and data analyzed using a linear model with physiologic and lifestyle characteristics as explanatory variables. Model reduction was used to assess which explanatory variables contributed most to the postprandial TG response. Results. TG responses to a high-fat meal were variable between individuals, with approximately 57 % of participants exceeded the nonfasting threshold for hypertriglyceridemia. Visceral adiposity was the strongest predictor of TG iAUC (β = 0.53, p = 0.01), followed by aerobic exercise frequency (β = 0.31, p = 0.05), insulin resistance based on HOMA-IR (β = 0.30, p = 0.04), and relative exercise intensity at which substrate utilization crossover occurred (β = 0.05, p = 0.04). For postprandial TG magnitude, visceral adiposity was a strong predictor (β = 0.43, p < 0.001) followed by aerobic exercise frequency (β = 0.23, p = 0.01), and exercise intensity for substrate utilization crossover (β = 0.53, p = 0.01). Conclusions. Postprandial TG responses to a high-fat meal was partially explained by several physiologic and lifestyle characteristics, including visceral adiposity, insulin resistance, aerobic exercise frequency, and relative substrate utilization crossover during exercise.Item Vaginal microbiota of American Indian women and associations with measures of psychosocial stress(Public Library of Science, 2021-12) Borgogna, Joanna-Lynn C.; Anastario, Michael; Firemoon, Paula; Rink, Elizabeth; Ricker, Adriann; Ravel, Jacques; Brotman, Rebecca M.; Yeoman, Carl J.Molecular-bacterial vaginosis (BV) is characterized by low levels of vaginal Lactobacillus species and is associated with higher risk of sexually transmitted infections (STI). Perceived psychosocial stress is associated with increased severity and persistence of infections, including STIs. American Indians have the highest rates of stress and high rates of STIs. The prevalence of molecular-BV among American Indian women is unknown. We sought to evaluate measures of psychosocial stress, such as historic loss (a multigenerational factor involving slavery, forced removal from one’s land, legally ratified race-based segregation, and contemporary discrimination) and their association with the vaginal microbiota and specific metabolites associated with BV, in 70 Northwestern Plains American Indian women. Demographics, perceived psychosocial stressors, sexual practices, and known BV risk factors were assessed using a modified version of the American Indian Service Utilization, Psychiatric Epidemiology, Risk and Protective Factors Project survey. Self-collected mid-vaginal swabs were profiled for bacterial composition by 16S rRNA gene amplicon sequencing and metabolites quantified by targeted liquid-chromatography mass spectrometry. Sixty-six percent of the participants were classified as having molecular-BV, with the rest being either dominated by L. crispatus (10%) or L. iners (24%). High levels of lifetime trauma were associated with higher odds of having molecular-BV (adjusted Odds Ratio (aOR): 2.5, 95% Credible Interval (CrI): 1.1–5.3). Measures of psychosocial stress, including historic loss and historic loss associated symptoms, were significantly associated with lifestyle and behavioral practices. Higher scores of lifetime trauma were associated with increased concentrations of spermine (aFC: 3.3, 95% CrI: 1.2–9.2). Historic loss associated symptoms and biogenic amines were the major correlates of molecular-BV. Historical loss associated symptoms and lifetime trauma are potentially important underlying factors associated with BV.Item Perceived Stress and Molecular-BV in the NIH Longitudinal Study of Vaginal Flora(Oxford University Press, 2021-05) Turpin, Rodman; Slopen, Natalie; Borgogna, Joanna C.; Yeoman, Carl J.; He, Xin; Miller, Ryan S.; Klebanoff, Mark A.; Ravel, Jacques; Brotman, Rebecca M.Vaginal microbiota provide the first line of defense against urogenital infections primarily through protective actions of Lactobacillus spp. Perceived stress increases susceptibility to infection through several mechanisms, including suppression of immune function. We investigated if stress was associated with deleterious changes to vaginal bacterial composition in a subsample of 572 women in the Longitudinal Study of Vaginal Flora, sampled from 1999 through 2002. Using Cox proportional-hazard models, both unadjusted and adjusted for sociodemographics and sexual behaviors, participants who exhibited a 5 unit-increase in Cohen’s perceived stress scale had greater risk (aHR=1.40, 95% CI 1.13-1.74) of developing molecular bacterial vaginosis (BV), a state with low Lactobacillus abundance and diverse anaerobic bacteria. A 5-unit stress increase was also associated with greater risks for transitioning from the L. iners-dominated community state type (26% higher) to molecular-BV (aHR=1.26, 95% CI 1.01-1.56) or maintaining molecular-BV from baseline (aHR=1.23, 95% CI 1.01-1.47). Inversely, women with baseline molecular-BV reporting a 5-unit stress increase were less likely to transition to microbiota dominated by L. crispatus, L. gasseri, or L. jensenii (aHR=0.81, 95% CI 0.68-0.99). These findings suggest psychosocial stress is associated with vaginal microbiota composition, inviting a more mechanistic exploration of the relationship between psychosocial stress and molecular-BV.Item Biogenic Amines Increase the Odds of Bacterial Vaginosis and Affect the Growth of and Lactic Acid Production by Vaginal Lactobacillus spp.(American Society for Microbiology, 2021-04) Borgogna, Joanna-Lynn C.; Shardell, Michelle D.; Grace, Savannah G.; Santori, Elisa K.; Americus, Benjamin; Li, Zhong; Ulanov, Alexander; Forney, Larry; Nelson, Tiffanie M.; Brotman, Rebecca M.; Ravel, Jacques; Yeoman, Carl J.Bacterial vaginosis (BV) is the most common vaginal disorder of reproductive-aged women, yet its etiology remains enigmatic. One clinical symptom of BV, malodor, is linked to the microbial production of biogenic amines (BA). Using targeted liquid chromatography mass spectrometry, we analyzed 149 longitudinally collected vaginal samples to determine the in vivo concentrations of the most common BAs and then assessed their relationship to BV and effect upon the growth kinetics of axenically cultured vaginal Lactobacillus species. Increases in cadaverine, putrescine, and tyramine were associated with greater odds of women transitioning from L. crispatus-dominated vaginal microbiota to microbiota that have a paucity of Lactobacillus spp. and from Nugent scores of 0 to 3 to Nugent scores of 7 to 10, consistent with BV. Exposure to putrescine lengthened the lag time and/or slowed the growth of all vaginal Lactobacillus spp. except L. jensenii 62G. L. iners AB107’s lag time was lengthened by cadaverine but reduced in the presence of spermidine and spermine. The growth rate of L. crispatus VPI 3199 was slowed by cadaverine and tyramine, and strain-specific responses to spermine and spermidine were observed. BAs were associated with reduced production of d- and l-lactic acid by vaginal Lactobacillus spp., and this effect was independent of their effect upon Lactobacillus species growth. The exceptions were higher levels of d- and l-lactic acid by two strains of L. crispatus when grown in the presence of spermine. Results of this study provide evidence of a direct impact of common biogenic amines on vaginal Lactobacillus spp.Item Relationships among intramammary health, udder and teat characteristics, and productivity of extensively managed ewes(Oxford University Press, 2021-02) Knuth, Ryan M.; Stewart, Whit C.; Taylor, Joshua B.; Bisha, Bledar; Yeoman, Carl J.; Van Emon, Megan L.; Murphy, Thomas W.Mastitis is an economically important disease and its subclinical state is difficult to diagnose, which makes mitigation more challenging. The objectives of this study were to screen clinically healthy ewes in order to 1) identify cultivable microbial species in milk, 2) evaluate somatic cell count (SCC) thresholds associated with intramammary infection, and 3) estimate relationships between udder and teat morphometric traits, SCC, and ewe productivity. Milk was collected from two flocks in early (<5 d) and peak (30 to 45 d) lactation to quantify SCC (n = 530) and numerate cultivable microbial species by culture-based isolation followed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS; n = 243) identification. Within flock and lactation stage, 11% to 74% (mean = 36%) of samples were culture positive. More than 50 unique identifications were classified by MALDI-TOF MS analysis, and Bacillus licheniformis (18% to 27%), Micrococcus flavus (25%), Bacillus amyloliquefaciens (7% to 18%), and Staphylococcus epidermidis (26%) were among the most common within flock and across lactation stage. Optimum SCC thresholds to identify culture-positive samples ranged from 175 × 103 to 1,675 × 103 cells/mL. Ewe productivity was assessed as total 120-d adjusted litter weight (LW120) and analyzed within flock with breed, parity, year, and the linear covariate of log10 SCC (LSCC) at early or peak lactation. Although dependent on lactation stage and year, each 1-unit increase in LSCC (e.g., an increase in SCC from 100 × 103 to 1,000 × 103 cells/mL) was predicted to decrease LW120 between 9.5 and 16.1 kg when significant. Udder and teat traits included udder circumference, teat length, teat placement, and degree of separation of the udder halves. Correlations between traits were generally low to moderate within and across lactation stage and most were not consistently predictive of ewe LSCC. Overall, the frequencies of bacteria-positive milk samples indicated that subclinical mastitis (SCM) is common in these flocks and can impact ewe productivity. Therefore, future research is warranted to investigate pathways and timing of microbial invasion, genomic regions associated with susceptibility, and husbandry to mitigate the impact of SCM in extensively managed ewes.Item In Vivo Competitions between Fibrobacter succinogenes, Ruminococcus flavefaciens, and Ruminoccus albus in a Gnotobiotic Sheep Model Revealed by Multi-Omic Analyses(American Society for Microbiology, 2021-04) Yeoman, Carl J.; Fields, Christopher J.; Lepercq, Pascale; Ruiz, Philippe; Forano, Evelyne; White, Bryan A.; Mosoni, PascaleRuminant animals, including cattle and sheep, depend on their rumen microbiota to digest plant biomass and convert it into absorbable energy. Considering that the extent of meat and milk production depends on the efficiency of the microbiota to deconstruct plant cell walls, the functionality of predominant rumen cellulolytic bacteria, Fibrobacter succinogenes , Ruminococcus albus , and Ruminococcus flavefaciens , has been extensively studied in vitro to obtain a better knowledge of how they operate to hydrolyze polysaccharides and ultimately find ways to enhance animal production.Item Physical Activity and Inflammation Phenotype Conversion(Clinical Exercise Physiology Association, 2019) MIles, Mary P.; Wilson, Stephanie; Yeoman, Carl J.Inflammation is a protective response to infection or injury; however, persistent microtraumas at the tissue level may result in chronic low-grade inflammation that plays both direct and indirect roles in the development of many diseases and aging. The purpose of this review is to describe the underlying physiology of low-grade inflammation and highlight potential inflammation lowering effects of physical activity (PA). Unique contributions of this review are to introduce the concept of inflammation phenotype flexibility in contrast to the low-grade inflammation state and describe how PA influences inflammation phenotype by altering muscle, gut, adipose, and postprandial metabolism. Pro-inflammatory M1 macrophages and cytokines—such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6—contribute to low-grade inflammation. Among the mechanisms that commonly contribute to low-grade inflammation are dysfunctional adipose tissue, a leaky gut, gut microbiota that promotes inflammation, and large postprandial glycemic and lipidemic responses. Physical activity may lower inflammation by decreasing M1 macrophages in visceral adipose tissue, decreasing adipose tissue volume, production of anti-inflammatory myokines, promotion of butyrate-producing members of the gut microbiota, improved gut barrier function, and lowering of postprandial glycemic and lipidemic responses. While exercise has many anti-inflammatory mechanisms, phenotype conversion is complex, multifaceted, and difficult to achieve. Our understanding of how PA influences inflammation must include acute exercise-induced anti-inflammatory effects, contribution to the inflammation state from multiple sources in the body, and phenotypic shifts underpinning low-grade inflammation.Item Dryland Cropping Systems, Weed Communities, and Disease Status Modulate the Effect of Climate Conditions on Wheat Soil Bacterial Communities(2020-08) Ishaq, Suzanne L.; Seipel, Tim F.; Yeoman, Carl J.; Menalled, Fabian D.Little knowledge exists on how soil bacteria in agricultural settings are impacted by management practices and environmental conditions in current and predicted climate scenarios. We assessed the impact of soil moisture, soil temperature, weed communities, and disease status on soil bacterial communities in three cropping systems: (i) conventional no-till (CNT) systems utilizing synthetic pesticides and herbicides, (ii) USDA-certified tilled organic (OT) systems, and (iii) USDA-certified organic systems with sheep grazing (OG). Sampling date within the growing season and associated soil temperature and moisture exerted the greatest effect on bacterial communities, followed by cropping system, Wheat streak mosaic virus (WSMV) infection status, and weed community. Soil temperature was negatively correlated with bacterial richness and evenness, while soil moisture was positively correlated with bacterial richness and evenness. Soil temperature and soil moisture independently altered soil bacterial community similarity between treatments. Inoculation of wheat with WSMV altered the associated soil bacteria, and there were interactions between disease status and cropping system, sampling date, and climate conditions, indicating the effect of multiple stressors on bacterial communities in soil. In May and July, cropping system altered the effect of climate change on the bacterial community composition in hotter conditions and in hotter and drier conditions compared to ambient conditions, in samples not treated with WSMV. Overall, this study indicates that predicted climate modifications as well as biological stressors play a fundamental role in the impact of cropping systems on soil bacterial communities.Item Plasticity in the Human Gut Microbiome Defies Evolutionary Constraints(2019-07-19) Gomez, Andres; Sharma, Ashok Kumar; Mallott, Elizabeth K.; Petrzelkova, Klara J.; Jost Robinson, Carolyn A.; Yeoman, Carl J.; Carbonero, Franck; Pafco, Barbora; Rothman, Jessica M.; Ulanov, Alexander; Vlckova, Klara; Amato, Katherine R.; Schnorr, Stephanie L.; Dominy, Nathaniel J.; Modry, David; Todd, Angelique F.; Torralba, Manolito; Nelson, Karen E.; Burns, Michael B.; Blekhman, Ran; Remis, Melissa; Stumpf, Rebecca M.; Wilson, Brenda A.; Gaskins, H. Rex; Garber, Paul A.; White, Bryan A.; Leigh, Steven R.The gut microbiome of primates, including humans, is reported to closely follow host evolutionary history, with gut microbiome composition being specific to the genetic background of its primate host. However, the comparative models used to date have mainly included a limited set of closely related primates. To further understand the forces that shape the primate gut microbiome, with reference to human populations, we expanded the comparative analysis of variation among gut microbiome compositions and their primate hosts, including 9 different primate species and 4 human groups characterized by a diverse set of subsistence patterns (n = 448 samples). The results show that the taxonomic composition of the human gut microbiome, at the genus level, exhibits increased compositional plasticity. Specifically, we show unexpected similarities between African Old World monkeys that rely on eclectic foraging and human populations engaging in nonindustrial subsistence patterns; these similarities transcend host phylogenetic constraints. Thus, instead of following evolutionary trends that would make their microbiomes more similar to that of conspecifics or more phylogenetically similar apes, gut microbiome composition in humans from nonindustrial populations resembles that of generalist cercopithecine monkeys. We also document that wild cercopithecine monkeys with eclectic diets and humans following nonindustrial subsistence patterns harbor high gut microbiome diversity that is not only higher than that seen in humans engaging in industrialized lifestyles but also higher compared to wild primates that typically consume fiber-rich diets.
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