Lisa Bramer

Dr. Lisa Bramer

orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
13 February 2017 in Nature Microbiology
Verified
Journal Article
Open access
PDF file
JHJonas Halfvarson
Jonas Halfvarson
CBColin J. Brislawn
Colin J. Brislawn
RLRegina Lamendella
Regina Lamendella
YVYoshiki Vázquez-Baeza
Yoshiki Vázquez-Baeza
WWWilliam A. Walters
William A. Walters
JJJanet K. Jansson
Janet K. Jansson
Inflammatory bowel disease (IBD) is characterized by flares of inflammation with a periodic need for increased medication and sometimes even surgery. The aetiology of IBD is partly attributed to a deregulated immune response to gut microbiome dysbiosis. Cross-sectional studies have revealed microbial signatures for different IBD subtypes, including ulcerative colitis, colonic Crohn's disease and ileal Crohn's disease. Although IBD is dynamic, microbiome studies have primarily focused on single time points or a few individuals. Here, we dissect the long-term dynamic behaviour of the gut microbiome in IBD and differentiate this from normal variation. Microbiomes of IBD subjects fluctuate more than those of healthy individuals, based on deviation from a newly defined healthy plane (HP). Ileal Crohn's disease subjects deviated most from the HP, especially subjects with surgical resection. Intriguingly, the microbiomes of some IBD subjects periodically visited the HP then deviated away from it. Inflammation was not directly correlated with distance to the healthy plane, but there was some correlation between observed dramatic fluctuations in the gut microbiome and intensified medication due to a flare of the disease. These results will help guide therapies that will redirect the gut microbiome towards a healthy state and maintain remission in IBD.

9 February 2023 in Frontiers in Artificial Intelligence
Verified
Journal Article
Open access
JFJavier E. Flores
Javier E. Flores
DCDaniel M. Claborne
Daniel M. Claborne
ZWZachary D. Weller
Zachary D. Weller
BWBobbie-Jo M. Webb-Robertson
Bobbie-Jo M. Webb-Robertson
KWKatrina M. Waters
Katrina M. Waters
Lisa BramerLisa Bramer
Lisa Bramer
Biological systems function through complex interactions between various ‘omics (biomolecules), and a more complete understanding of these systems is only possible through an integrated, multi-omic perspective. This has presented the need for the development of integration approaches that are able to capture the complex, often non-linear, interactions that define these biological systems and are adapted to the challenges of combining the heterogenous data across ‘omic views. A principal challenge to multi-omic integration is missing data because all biomolecules are not measured in all samples. Due to either cost, instrument sensitivity, or other experimental factors, data for a biological sample may be missing for one or more ‘omic techologies. Recent methodological developments in artificial intelligence and statistical learning have greatly facilitated the analyses of multi-omics data, however many of these techniques assume access to completely observed data. A subset of these methods incorporate mechanisms for handling partially observed samples, and these methods are the focus of this review. We describe recently developed approaches, noting their primary use cases and highlighting each method's approach to handling missing data. We additionally provide an overview of the more traditional missing data workflows and their limitations; and we discuss potential avenues for further developments as well as how the missing data issue and its current solutions may generalize beyond the multi-omics context.

3 August 2015 in Proceedings of the National Academy of Sciences
Verified
Journal Article
Open access
PDF file
MHMohamad Hejazi
Mohamad Hejazi
NVNathalie Voisin
Nathalie Voisin
Lu LiuLu Liu
Lu Liu
Lisa BramerLisa Bramer
Lisa Bramer
DFDaniel C. Fortin
Daniel C. Fortin
Yuyu ZhouYuyu Zhou
Yuyu Zhou
Significance: Devising sustainable climate change mitigation policies with attention to potential synergies and constraints within the climate–energy–water nexus is the subject of ongoing integrated modeling efforts. This study employs a regional integrated assessment model and a regional Earth system model at high spatial and temporal resolutions in the Unites States to compare the implications of two of the representative concentration pathways under consistent socioeconomics. The results clearly show, for the first time to our knowledge, that climate change mitigation policies, if not designed with careful attention to water resources, could increase the magnitude, spatial coverage, and frequency of water deficits. The results challenge the general perception that mitigation that aims at reducing warming also would alleviate water deficits in the future.

21 July 2020 in Nature Communications
Verified
Journal Article
Open access
PDF file
HLHans C. Leier
Hans C. Leier
JWJules B. Weinstein
Jules B. Weinstein
JKJennifer E. Kyle
Jennifer E. Kyle
JLJOON-YONG LEE
JOON-YONG LEE
Lisa BramerLisa Bramer
Lisa Bramer
FTFikadu Tafesse
Fikadu Tafesse
Zika virus (ZIKV), an arbovirus of global concern, remodels intracellular membranes to form replication sites. How ZIKV dysregulates lipid networks to allow this, and consequences for disease, is poorly understood. Here, we perform comprehensive lipidomics to create a lipid network map during ZIKV infection. We find that ZIKV significantly alters host lipid composition, with the most striking changes seen within subclasses of sphingolipids. Ectopic expression of ZIKV NS4B protein results in similar changes, demonstrating a role for NS4B in modulating sphingolipid pathways. Disruption of sphingolipid biosynthesis in various cell types, including human neural progenitor cells, blocks ZIKV infection. Additionally, the sphingolipid ceramide redistributes to ZIKV replication sites, and increasing ceramide levels by multiple pathways sensitizes cells to ZIKV infection. Thus, we identify a sphingolipid metabolic network with a critical role in ZIKV replication and show that ceramide flux is a key mediator of ZIKV infection.

27 February 2022 in Journal of Proteome Research
Verified
Journal Article
Closed access
DPDeanna L. Plubell
Deanna L. Plubell
LKLukas Käll
Lukas Käll
BWBobbie-Jo Webb-Robertson
Bobbie-Jo Webb-Robertson
Lisa BramerLisa Bramer
Lisa Bramer
AIAshley Ives
Ashley Ives
MMMichael J. MacCoss
Michael J. MacCoss

20 December 2017 in Journal of Geophysical Research: Biogeosciences
Verified
Journal Article
Open access
PDF file
EGEmily Graham
Emily Graham
Malak TfailyMalak Tfaily
Malak Tfaily
ACAlex Crump
Alex Crump
AGAmy Goldman
Amy Goldman
Lisa BramerLisa Bramer
Lisa Bramer
JSJames Stegen
James Stegen
In light of increasing terrestrial carbon (C) transport across aquatic boundaries, the mechanisms governing organic carbon (OC) oxidation along terrestrial‐aquatic interfaces are crucial to future climate predictions. Here we investigate the biochemistry, metabolic pathways, and thermodynamics corresponding to OC oxidation in the Columbia River corridor using ultrahigh‐resolution C characterization. We leverage natural vegetative differences to encompass variation in terrestrial C inputs. Our results suggest that decreases in terrestrial C deposition associated with diminished riparian vegetation induce oxidation of physically bound OC. We also find that contrasting metabolic pathways oxidize OC in the presence and absence of vegetation and—in direct conflict with the “priming” concept—that inputs of water‐soluble and thermodynamically favorable terrestrial OC protect bound‐OC from oxidation. In both environments, the most thermodynamically favorable compounds appear to be preferentially oxidized regardless of which OC pool microbiomes metabolize. In turn, we suggest that the extent of riparian vegetation causes sediment microbiomes to locally adapt to oxidize a particular pool of OC but that common thermodynamic principles govern the oxidation of each pool (i.e., water‐soluble or physically bound). Finally, we propose a mechanistic conceptualization of OC oxidation along terrestrial‐aquatic interfaces that can be used to model heterogeneous patterns of OC loss under changing land cover distributions.