ASBMB Annual Meeting

Detecting infection complications with nanoscale bacterial buds

Findings suggest a quick, efficient way to diagnose Gram-negative sepsis
Jessica Desamero
March 24, 2024

Sepsis is an inflammatory overreaction to an infection, viral or bacterial, within the body and is the leading cause of death in hospitals. The reaction causes changes such as an intense fever or lowered blood pressure, which may damage vital organ systems if not promptly treated. Early detection may help save lives, but diagnosing patients with sepsis remains a clinical challenge. 

Outer membrane vesicles, or OMVs, are nanoscale buds released from the outer membranes of Gram-negative bacteria in response to stress or other environmental changes. Bacteria use these OMVs to remove unwanted molecules and share helpful biomolecules with each other. OMVs can also trigger an inflammatory response during infection. Detecting these buds may be a quicker and more efficient way to identify Gram-negative bacterial sepsis than current diagnostic methods. 

ASBMB
Nico Burgado tells Ann Stock, president of the ASBMB, about his poster at the 2023 annual meeting in Seattle.

Nico Burgado, an undergraduate student in Lea Michel’s lab at the Rochester Institute of Technology, has been studying OMVs.  “Usually, when doctors are trying to diagnose sepsis, the patients are already on antibiotics so when they take blood samples, no bacteria show up,” Burgado said. “We need a way to diagnose sepsis after they give the antibiotics, and a good way to do that is OMV detection.”

 Burgado, Michel and their team explored OMVs in relation to E. coli sepsis. “We can detect biomolecules that are specific to the parent bacteria,” Burgado said. “After we isolate the OMVs, these biomarkers can help us determine which bacteria are causing the sepsis.” 

In a recent study, the researchers used blood plasma samples collected from hospital patients by clinicians. The Michel team isolated the OMVs from these samples, using centrifugation, syringe filtering and ultracentrifugation. They then used Western blot analysis to detect the presence of E. coli proteins. 

“The antigens are specific for E. coli, so if we detect any bands, that should mean that there’s E. coli OMVs in the plasma sample,” Burgado said. 

The study showed that OMV detection is a promising method to diagnose Gram-negative sepsis. “The real clinical significance is that it’s a path to diagnosing sepsis, identifying the bacterial cause early on, and treating patients with the right antibiotics before they either have more complications or pass away,” Burgado said. 

So far, the team has shown that, for the most part, they can isolate E. coli OMVs from the plasma of sepsis patients and detect E. coli biomarkers in the samples. In future studies, the researchers plan to test the sensitivity and accuracy of their diagnostic method and establish a baseline for detecting OMVs from E. coli and other common sources of bacterial sepsis.

 
Dr_Microbe
Bacteria (blue) in the blood can cause deadly sepsis.

Details

Nico Burgado will present this research from 4:30 to 5:30 p.m. CDT on Monday, March 25, at Discover BMB 2024, the American Society for Biochemistry and Molecular Biology annual meeting in San Antonio. His poster is at Board 273.

Abstract title: Using outer membrane vesicles to diagnosis sepsis in clinical samples

Enjoy reading ASBMB Today?

Become a member to receive the print edition four times a year and the digital edition monthly.

Learn more
Jessica Desamero

Jessica Desamero is a graduate of the biochemistry Ph.D. program at the City University of New York Graduate Center. She volunteers with the science outreach organization BioBus, and she is an ASBMB Today volunteer contributor.

Get the latest from ASBMB Today

Enter your email address, and we’ll send you a weekly email with recent articles, interviews and more.

Latest in Science

Science highlights or most popular articles

What’s in a diagnosis?
Essay

What’s in a diagnosis?

Sept. 4, 2025

When Jessica Foglio’s son Ben was first diagnosed with cerebral palsy, the label didn’t feel right. Whole exome sequencing revealed a rare disorder called Salla disease. Now Jessica is building community and driving research for answers.

Peer through a window to the future of science
Annual Meeting

Peer through a window to the future of science

Sept. 3, 2025

Aaron Hoskins of the University of Wisconsin–Madison and Sandra Gabelli of Merck, co-chairs of the 2026 ASBMB annual meeting, to be held March 7–10, explain how this gathering will inspire new ideas and drive progress in molecular life sciences.

Glow-based assay sheds light on disease-causing mutations
Journal News

Glow-based assay sheds light on disease-causing mutations

Sept. 2, 2025

University of Michigan researchers create a way to screen protein structure changes caused by mutations that may lead to new rare disease therapeutics.

How signals shape DNA via gene regulation
Journal News

How signals shape DNA via gene regulation

Aug. 19, 2025

A new chromatin isolation technique reveals how signaling pathways reshape DNA-bound proteins, offering insight into potential targets for precision therapies. Read more about this recent MCP paper.

A game changer in cancer kinase target profiling
Journal News

A game changer in cancer kinase target profiling

Aug. 19, 2025

A new phosphonate-tagging method improves kinase inhibitor profiling, revealing off-target effects and paving the way for safer, more precise cancer therapies tailored to individual patients. Read more about this recent MCP paper.

How scientists identified a new neuromuscular disease
Feature

How scientists identified a new neuromuscular disease

Aug. 14, 2025

NIH researchers discover Morimoto–Ryu–Malicdan syndrome, after finding shared symptoms and RFC4 gene variants in nine patients, offering hope for faster diagnosis and future treatments.