Extracellular Bacteria
Extracellular Bacteria - Related Videos
03:53
Isolation and Enrichment of Outer Membrane-Derived Extracellular Vesicles from Bacteria
0 Views •
2025
Source: Watson, D. C., et.al. Scalable Isolation and Purification of Extracellular Vesicles from Escherichia coli and Other Bacteria. J. Vis. Exp. (2021)This video demonstrates the isolation and concentration of extracellular vesicles (EVs) derived from the outer membrane of genetically engineered bacteria. The process involves culturing the bacteria to release EVs, followed by sequential centrifugation and filtration steps to remove cells and debris. Finally, ultrafiltration is used to...
09:56
Scalable Isolation and Purification of Extracellular Vesicles from Escherichia coli and Other Bacteria
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Cited by 17 •
2021
Bacteria secrete nanometer-sized extracellular vesicles (EVs) carrying bioactive biological molecules. EV research focuses on understanding their biogenesis, role in microbe-microbe and host-microbe interactions and disease, as well as their potential therapeutic applications. A workflow for scalable isolation of EVs from various bacteria is presented to facilitate standardization of EV research.
04:04
Lysostaphin-Based Enzyme Protection Assay: An In Vitro Method to Quantify Intracellular Staphylococcus aureus Load by Enzyme-Mediated Selective Killing of Extracellular Bacteria
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2025
In this video, we demonstrate a lysostaphin-based in vitro enzyme protection assay to quantify the Staphylococcus aureus internalization in A549 cells. The assay helps in qualitative, quantitative, and characterization studies of the intracellular bacterial load in the host cells.
13:20
Detection of Bacteria Using Fluorogenic DNAzymes
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Cited by 17 •
2012
We have recently reported a novel approach for generating fluorogenic DNAzyme probes that can be applied to set up a simple, "mix-and-read" fluorescent assay for bacterial detection. These special DNA probes catalyze the cleavage of a chromophore-modified DNA-RNA chimeric substrate in the presence of crude extracellular mixture (CEM) produced by a specific bacterium, thereby translating bacterial detection into fluorescence signal generation. In this report we will describe key experimental...
02:03
Enrichment of Anode-Respiring Bacteria Using an On-Site Electrochemical System
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2025
Source: Okamoto, A., et al. Self-standing Electrochemical Set-up to Enrich Anode-respiring Bacteria On-site. J. Vis. Exp. (2018)This video demonstrates the use of an on-site electrochemical system to enrich anode-respiring bacteria (ARB) from natural reservoirs. A redox gradient is established by placing the anode in oxygen-free deep water and the cathode in oxygen-rich surface water. ARB form biofilms and transfer electrons to the anode, which flows to the cathode, where oxygen is reduced,...
FAQs
Recognition begins when pattern-recognition receptors detect molecular features on bacterial surfaces or products released outside the cell. This sensing links microbial presence to innate immune activation and helps explain why both structural components and secreted factors matter. In infection research, separating these signals clarifies how bacteria initiate host responses alongside antibody-driven protection.
These defenses contribute through complementary mechanisms. Complement and antibodies can opsonize bacteria, marking them for more efficient recognition and uptake by phagocytes. Complement may also participate in membrane attack, while phagocytes engulf targeted organisms. Examining these interactions shows how soluble immune factors and cellular defenses combine to limit bacterial survival.
Clearance can fail when bacterial surface molecules or secreted products interfere with effective recognition and elimination. When containment is inadequate, continued microbial activity and host responses may extend beyond the initial site, producing systemic inflammation. This relationship makes immune evasion and inflammatory injury important subjects in extracellular bacterial pathogenesis.
A useful framework follows recognition, complement and antibody activity, phagocyte engagement, bacterial containment, and the development of inflammation. Investigators can then relate these coordinated responses to whether organisms are eliminated or persist. This sequence connects innate and adaptive defenses while providing a structure for interpreting why infection remains localized or becomes systemic.
They are especially relevant when researchers aim to prevent bacterial colonization or disease, improve elimination, or limit damage caused by microbial products and inflammation. Studying surface molecules, secreted factors, and immune clearance can identify protective targets and therapeutic opportunities. These findings support vaccine design and antimicrobial development within infection research.
Host-directed therapies focus on improving or regulating the immune response rather than acting only on the microorganism. Their rationale follows from the cooperation of pattern-recognition receptors, complement, antibodies, and phagocytes, as well as the possibility of harmful systemic inflammation. Evaluating these pathways may help distinguish better bacterial control from excessive tissue-damaging inflammation.