Related Experiment Video
Updated: Jun 19, 2026
06:05
Using the Overlay Assay to Qualitatively Measure Bacterial Production of and Sensitivity to Pneumococcal Bacteriocins
Published on: September 30, 2014
THE ELABORATION OF SPECIFIC SOLUBLE SUBSTANCE BY PNEUMOCOCCUS DURING GROWTH
1Hospital of The Rockefeller Institute for Medical Research.
The Journal of Experimental Medicine
|October 30, 2009
Summary
A specific soluble substance from pneumococcus bacteria is released by living organisms and found in infected animals and pneumonia patients. Its presence in urine can indicate a poor prognosis and aid in diagnosis.
Area of Science:
- Microbiology
- Immunology
- Biochemistry
Background:
- Pneumococcus bacteria produce a specific substance during active growth.
- This substance is extruded by living bacteria, not solely from cell lysis.
Purpose of the Study:
- To investigate the presence and characteristics of a specific soluble substance of pneumococcus origin.
- To determine the diagnostic and prognostic value of this substance in pneumococcal infections.
Main Methods:
- Culturing pneumococcus and analyzing cell-free fluids.
- Experimentally infecting rabbits and analyzing blood and urine.
- Analyzing blood and urine samples from human patients with lobar pneumonia.
Main Results:
- The specific soluble substance was detected in pneumococcus cultures, infected rabbits, and pneumonia patients.
- Higher concentrations in patient urine correlated with unfavorable prognosis.
- The substance demonstrated resistance to heat, alcohol, acetone, ether, and trypsin digestion.
Conclusions:
- A specific soluble substance is actively released by pneumococcus.
- This substance is detectable in biological fluids during infection and holds diagnostic and prognostic significance.
- The substance's stability suggests potential for further characterization and therapeutic investigation.
More Related Videos
11:32Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria
Published on: February 23, 2014
09:20Investigating the Effects of Probiotics on Pneumococcal Colonization Using an In Vitro Adherence Assay
Published on: April 28, 2014
Related Concept Videos
01:19Formation of Lipopolysaccharides
Lipopolysaccharides (LPS) are crucial components of the outer membrane of Gram-negative bacteria, serving both structural and functional roles. It contributes to membrane stability and protects bacteria from host immune responses. LPS is composed of three major regions—lipid A, a core oligosaccharide, and an O antigen. The biosynthesis and assembly of LPS involve a highly coordinated set of enzymatic reactions and transport mechanisms. Additionally, LPS is recognized as an endotoxin, triggering...
01:28Peptidoglycan Synthesis
Structure of PeptidoglycanPeptidoglycan is a vital structural component of the bacterial cell wall, providing mechanical strength and shape to the cell. It consists of repeating units of two sugars—N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM)—linked by β-1,4 glycosidic bonds. These sugar chains are cross-linked by short peptide chains, forming a mesh-like polymer that surrounds the bacterial plasma membrane.Cytoplasmic Phase – Precursor SynthesisPeptidoglycan biosynthesis begins in...
01:17Gene Regulation During Sporulation
Sporulation is a complex developmental process that allows certain Gram-positive bacteria, such as Bacillus subtilis and Clostridium species, to survive extreme environmental conditions. This process is tightly regulated by a series of signaling cascades and transcriptional controls, ensuring the formation of a highly resistant endospore.Sporulation is triggered by unfavorable conditions, such as nutrient depletion, and is governed by a phosphorelay system. One of the sensor kinases, such as...
01:27Production of Antibiotics
Penicillin, one of the earliest and most widely used antibiotics, is produced industrially by the filamentous fungus Penicillium chrysogenum. Large stirred-tank bioreactors ranging from tens to hundreds of thousands of liters maintain tightly controlled temperature, pH, and dissolved oxygen conditions to support fungal metabolism and maximize antibiotic yield. Penicillin is a secondary metabolite, synthesized primarily during the stationary growth phase, which requires a carefully managed...
01:13Special Staining Techniques
Specialized staining techniques play a vital role in microbiology by enabling the visualization of specific bacterial structures that remain undetectable with standard microscopy methods. These techniques not only enhance the structural visualization of bacterial cells but also provide critical insights into their pathogenicity and classification. Additionally, they support diagnostic and research endeavors in microbiology by identifying key bacterial features.Capsule Staining for Virulence...
01:14Atypical Pneumonia
Atypical pneumonia, often caused by Mycoplasma pneumoniae, is a form of pulmonary infection that differs from the classical presentation of bacterial pneumonia in both its cause and clinical symptoms. Mycoplasma pneumoniae is a pleomorphic bacterium notable for its lack of a rigid cell wall. This structural characteristic imparts resistance to beta-lactam antibiotics and significantly influences the bacterium’s behavior within the human host.Other pathogens responsible for the disease include...