Center for Microbial Dynamics and Infection
banner
cmdi.bsky.social
Center for Microbial Dynamics and Infection
@cmdi.bsky.social
Our team of researchers at GeorgiaTech investigate mechanisms and consequences of microbial community dynamics both in the environment and during infection. https://sites.gatech.edu/cmdi/
Extreme drought makes peatlands lose carbon much faster, and this loss is worsened by both warming and elevated CO₂. Climate change will significantly amplify carbon emissions from peatlands in the future. 🌡️🔥 #ClimateChange #Peatlands #CarbonCycle
pubmed.ncbi.nlm.nih.gov/41129626/
Drought-induced peatland carbon loss exacerbated by elevated CO2 and warming - PubMed
Extreme drought events are predicted to increase with climate change, yet their impacts on ecosystem carbon dynamics under warming and elevated carbon dioxide (eCO<sub>2</sub>) remain unclear. In a peatland experiment with five warming treatments each under ambient carbon dioxide (aCO<sub>2</sub>) a …
pubmed.ncbi.nlm.nih.gov
November 25, 2025 at 7:16 PM
Screened marine natural product extracts reveals two glycoglycerolipids that act as inhibitors of the Naᵥ1.7 ion channel. These findings from red algae, sponges, and corals offer exciting new leads for drug discovery! 🌊💊#DrugDiscovery #MarineBiology pubmed.ncbi.nlm.nih.gov/41124213/
Discovery of Nav1.7 Inhibitors through the Screening of Marine Natural Product Extracts - PubMed
Automated high-throughput screening of a prefractionated extract library of marine macroorganisms identified 239 hits (hit rate 2.5%), including a marine algal extract that blocked the Na<sub>v</sub>1.7 channel in a fluorescent-based flux assay. Bioactivity-guided chemical investigation led to the i …
pubmed.ncbi.nlm.nih.gov
November 25, 2025 at 7:15 PM
Spatial organization of bacteria in thin films, like soil, is largely determined by a purely physical mechanism: capillary interactions (water tension). 🦠💧 #Microbiology #Biophysics #CurrentBiology pubmed.ncbi.nlm.nih.gov/41118734/
Microbial population structure: Forced proximity is shaped by capillary interactions - PubMed
A recent study shows that the spatial organization of bacteria in thin films or near air-water interfaces is strongly impacted by a purely physical mechanism - capillary interactions. This mechanism likely plays an important role in bacterial assortment in environments like soil, which undergo wet a …
pubmed.ncbi.nlm.nih.gov
November 25, 2025 at 7:12 PM
In intubated children, longitudinal analysis of the respiratory microbiome reveals dynamic shifts in microbial communities under empiric antibiotic therapy, with implications for pathogen emergence and treatment strategies.
Mapping the respiratory microbiome in intubated children over time | Microbiology Spectrum
Clinicians often prescribe empirical antibiotics for critically ill, intubated children with suspected respiratory infections, contributing to antibiotic overuse and challenging antimicrobial stewardship. Our longitudinal tracheal aspirate analysis of cultures and 16S rDNA sequencing revealed significant inter-patient variability, regardless of the primary reason for intubation. We observed both concordance and discrepancies between clinical microbiology and sequencing results—gram-negative organisms aligned well between methods, whereas Streptococcus was detected in 34 of 39 samples by 16S rDNA but only once by culture. Our findings emphasize the value of longitudinal airway microbiome analysis in pediatric patients. Given the heterogeneous pathologies and diverse age groups in pediatric intensive care, future large-scale studies should account for antibiotic exposure, commensal bacterial interactions, and clinical conditions that influence microbiome dynamics. Expanding research in this area could improve our understanding of microbial shifts in critically ill children and inform more targeted treatment strategies.
journals.asm.org
November 17, 2025 at 3:54 PM
A step-by-step guide to using CNC micro-milling to fabricate microfluidic master molds and PDMS devices (e.g., organ-on-a-chip), including design (SolidWorks/Fusion), machining, mould casting and bonding.
A Protocol Guide to Micro Milling for Bio-Microfluidics
Micro milling is a subtractive manufacturing method for fabricating micro-scale three-dimensional features from hard substrates like acrylic, wood, or metal. It enables rapid prototyping of biomicrofl...
bio-protocol.org
November 17, 2025 at 3:52 PM
This study on the rhizosphere of the salt-marsh plant Spartina alterniflora reveals a highly diverse viral community—metagenomic analysis of root-zone samples showed that viruses of microorganisms influence microbial population dynamics, community structure, nutrient cycling and gene-transfer.
Viral community diversity in the rhizosphere of the foundation salt marsh plant Spartina alterniflora | mSphere
Salt marshes are vital coastal ecosystems. Microbes in these environments drive nutrient cycling and support plant health, with Spartina alterniflora serving as a foundation species. This study explores viral communities associated with S. alterniflora, revealing how plant compartments and phenotypes shape viral composition. The discovery of numerous novel viruses, some potentially influencing microbes involved in key biogeochemical processes, highlights their ecological significance. Given the increasing pressures on coastal ecosystems, understanding virus-microbe-plant interactions is essential for predicting and managing ecosystem responses to environmental change.
journals.asm.org
November 17, 2025 at 3:50 PM
The morphotype switch from smooth to rough in M. abscessus alters gene-essentiality patterns both in vitro and in mouse infection; rough and smooth forms require different genes, affecting therapeutic target selection.
The role of colony morphotype in shaping gene essentiality in Mycobacteroides abscessus - PubMed
Changes in bacterial colony morphology are common during chronic human infections and are thought to provide a survival advantage. In the human pathogen <i>Mycobacteroides abscessus</i> (MAB), a unidirectional transition from a smooth (MAB<sup>S</sup>) to rough (MAB<sup>R</sup>) morphotype frequentl …
pubmed.ncbi.nlm.nih.gov
November 17, 2025 at 3:48 PM
Quantitative modelling of multi-signal quorum sensing in Pseudomonas aeruginosa reveals that its las and rhl signalling systems engage in reciprocal, non-linear and synergistic interactions rather than a simple hierarchy.
Quantitative modeling of multi-signal quorum-sensing maps environment to bacterial regulatory responses
Bacterial quorum sensing is often assumed to follow a strict hierarchy, limiting understanding of how multiple signals interact. This study finds that Pseudomonas aeruginosa uses a reciprocal, coopera...
journals.plos.org
November 17, 2025 at 3:46 PM
The study evolved Escherichia coli under constant glucose limitation for ≥300 generations and identified 39 genes repeatedly mutated, many regulatory factors, revealing structural protein constraints. bmcbiol.biomedcentral.com/articles/10....
November 17, 2025 at 3:45 PM
Peatland microbes resist warming, with stable communities and diverse carbon pathways; methanogens show metabolic flexibility but are not dominant. #MicroSky www.nature.com/articles/s41...
Northern peatland microbial communities exhibit resistance to warming and acquire electron acceptors from soil organic matter - Nature Communications
Climate change is expected to impact microbes degrading organic matter in northern peatlands. Here, using a warming experiment, the authors show that communities remain stable after three years of war...
www.nature.com
July 28, 2025 at 2:51 PM
Gene-specific RNA-to-protein conversion factors improve protein predictions from mRNA, enabling functional insights across diverse microbial species. #MicroSky journals.asm.org/doi/10.1128/...
Conserved cross-domain protein-to-mRNA ratios enable proteome prediction in microbes | mBio
Deciphering the biology of natural microbial communities is limited by the lack of functional data. While transcriptomics enables gene expression profiling, mRNA levels often fail to predict protein abundance, the primary indicator of microbial function. ...
journals.asm.org
July 28, 2025 at 2:49 PM
Alveolar macrophages limit phage therapy by clearing phages; their depletion boosts phage efficacy against P. aeruginosa in murine lung infection. #MicroSky www.nature.com/articles/s41...
Macrophage-induced reduction of bacteriophage density limits the efficacy of in vivo pulmonary phage therapy - Nature Communications
In vivo experiments and mathematical modelling in this work, show that alveolar macrophages lower phage densities and phage-bacteria contact rates, limiting the effectiveness of synergistic treatment ...
www.nature.com
July 28, 2025 at 2:48 PM
A simple model of vertical biofilm growth arises from active fluid dynamics, linking cell decay to growth limits and unifying early and late stages. #MicroSky pubmed.ncbi.nlm.nih.gov/40578390/
Biofilm vertical growth dynamics are captured by an active fluid framework - PubMed
Bacterial biofilms, surface-attached microbial communities, grow horizontally across surfaces and vertically above them. Although a simple heuristic model for vertical growth was experimentally shown ...
pubmed.ncbi.nlm.nih.gov
July 28, 2025 at 2:47 PM
Spontaneous fluid flows in yeast clusters enable nutrient transport and exponential growth, aiding multicellularity before genetic adaptations evolve. #MicroSky www.science.org/doi/10.1126/...
Metabolically driven flows enable exponential growth in macroscopic multicellular yeast
Metabolically generated flow is an emergent mechanism that alleviates diffusion limits in macroscopic multicellular yeast.
www.science.org
July 28, 2025 at 2:44 PM
This primer reviews differences between acute, chronic, mono- and polymicrobial infections, highlighting ecological and evolutionary challenges and opportunities for treatment and infection management. www.microbiologyresearch.org/content/jour...
Microbial Primer: Challenges and opportunities in the treatment of chronic polymicrobial infections ‒ an eco-evolutionary perspective
In this primer, we will review the key distinctions between acute and chronic infections, between mono- and polymicrobial infections and how these distinctions work together to generate the growing cr...
www.microbiologyresearch.org
June 20, 2025 at 5:59 PM
Mass spectrometry metabolomics methods reveal microbiome-derived natural products influencing host-microbe interactions, enabling insights into communication, immunity, and symbiosis mechanisms. pubs.rsc.org/en/content/a...
Mass spectrometry-based metabolomics approaches to interrogate host–microbiome interactions in mammalian systems
Covering: 2015 to 2025Chemical crosstalk is universal to all life, niche-specific, and essential to thrive. This crosstalk is mediated by a large diversity of molecules, including metal ions, small mo...
pubs.rsc.org
June 20, 2025 at 5:57 PM
This review explores the ecological niches, evolutionary dynamics, pathogenic mechanisms, and antimicrobial resistance profiles of Pseudomonas aeruginosa, highlighting its adaptability and clinical significance. www.nature.com/articles/s41...
Pseudomonas aeruginosa: ecology, evolution, pathogenesis and antimicrobial susceptibility - Nature Reviews Microbiology
Pseudomonas aeruginosa is a functionally versatile bacterium, a leading opportunistic human pathogen and a model organism in microbiology. In this Review, Letizia, Diggle and Whiteley discuss P. aerug...
www.nature.com
June 3, 2025 at 3:08 PM
In Chlamydomonas reinhardtii, multicellularity evolved under predation but not settling selection. Only certain genotypes gave rise to multicellular forms, showing both deterministic and random factors shape this transition. academic.oup.com/gbe/advance-...
Genetic predisposition towards multicellularity in Chlamydomonas reinhardtii
academic.oup.com
May 19, 2025 at 2:22 PM
Trimethoprim alters metabolite production in B. cenocepacia and A. fumigatus, affecting interkingdom interactions, antifungal activity, and fungal pigmentation, revealing how therapeutics reshape microbial chemistry and virulence expression. pubs.acs.org/doi/10.1021/...
Antimicrobial Agent Trimethoprim Influences Chemical Interactions in Cystic Fibrosis Pathogens via the ham Gene Cluster
The fungus Aspergillus fumigatus and the bacterium Burkholderia cenocepacia cause fatal respiratory infections in immunocompromised humans and patients with lung disease, such as cystic fibrosis (CF). In dual infections, antagonistic interactions contribute to increased mortality. These interactions are further altered by the presence of antimicrobial and antifungal agents. However, studies performed to date on chemical interactions between clinical B. cenocepacia and A. fumigatus have focused on pathogens in isolation and do not include the most abundant chemical signal, i.e., clinically administered therapeutics, present in the lung. Here, we characterize small molecule-mediated interactions between B. cenocepacia and A. fumigatus and their shift in response to trimethoprim exposure by using metabolomics and mass spectrometry imaging. Using these methods, we report that the production of several small-molecule natural products of both the bacteria and the fungus is affected by cocultivation and exposure to trimethoprim. By systematic analysis of metabolomics data, we hypothesize that the B. cenocepacia-encoded ham gene cluster plays a role in the trimethoprim-mediated alteration of bacterial–fungal interactions. We support our findings by generating a genetically modified strain lacking the ham gene cluster and querying its interaction with A. fumigatus. Using comparative analyses of the extracts of wild-type and knockout strains, we report the inactivation of a bacterially produced antifungal compound, fragin, by A. fumigatus, which was verified by the addition of purified fragin to the A. fumigatus culture. Furthermore, we report that trimethoprim does not inhibit fungal growth, but affects the biochemical pathway for DHN-melanin biosynthesis, an important antifungal drug target, altering the pigmentation of the fungal conidia and is associated with modification of ergosterol to ergosteryl-3β-O-l-valine in coculture. This study demonstrates the impact of therapeutics on shaping microbial and fungal metabolomes, which influence interkingdom interactions and the expression of virulence factors. Our findings enhance the understanding of the complexity of chemical interactions between therapeutic compounds, bacteria, and fungi and may contribute to the development of selective treatments.
pubs.acs.org
May 19, 2025 at 2:20 PM
Sea cucumbers reshape reef sediment microbiomes by grazing, reducing microbial biomass and phototrophs, enriching anaerobic genes, and potentially supporting coral survival through disease suppression. academic.oup.com/ismej/advanc...
Sea cucumber grazing linked to enrichment of anaerobic microbial metabolisms in coral reef sediments
Abstract. Sea cucumbers have been overharvested world-wide, making assessments of their ecological effects challenging, but recent research demonstrated th
academic.oup.com
May 9, 2025 at 5:19 PM
In the phosphorus-limited Sargasso Sea, microbes partition phosphorus uptake by time of day—bacteria in the morning, phytoplankton by day, and cyanobacteria at dusk—revealing a temporal niche strategy. www.pnas.org/doi/10.1073/...
Diel partitioning in microbial phosphorus acquisition in the Sargasso Sea | PNAS
The daily cycle of photosynthetic primary production at the base of marine food webs is often limited by the availability of scarce nutrients. Micr...
www.pnas.org
May 3, 2025 at 5:44 PM
Reposted by Center for Microbial Dynamics and Infection
Mystique is here! When I started my position at @cmdi.bsky.social there were no readily available phage against my A. baumannii focal strain. The solution? Finding my own phage ofc. Mystique is a broad host range Acinetobacter phage, and I'm thrilled to see this work out today #PhageSky 🧪🦠
Mystique, a broad host range Acinetobacter phage, reveals the impact of culturing conditions on phage isolation and infectivity
Author summary Bacterial infections caused by Acinetobacter baumannii are a major global health concern due to high antibiotic resistance, earning it a critical priority pathogen ranking by the WHO. P...
journals.plos.org
April 10, 2025 at 7:59 PM