Related Experiment Video
Updated: May 16, 2026
High-throughput Fluorometric Measurement of Potential Soil Extracellular Enzyme Activities
Published on: November 15, 2013
[Not Available]
J Dupy-Blanc1, C A Grolière, R Berrada
1Zoologie et Protistologie, U.A. du CNRS 138, Université Blaise-Pascal, Clermont-Ferrand, Aubière, France.
Abstract:
Antibiotics (30 mg/1) added at T 60 mn. lead, in a part of the population, to an increase of the macronuclear DNA content resulting from DNA activity during a phase S 2 which begins after the phase G 2. The largest cells have the highest DNA content and the longest generation time. The results are confirmed by autoradiography with tritiated thymidine. The percentage of macronuclear labelling increases from T 150 to a maximum at T 180, and it is greater with nigericin (46%) than with epinigericin (37%). Thus, epinigericin is less toxic than nigericin.
Insights
Antibiotics can increase macronuclear DNA content, especially in larger cells with longer generation times. Epinigericin is less toxic than nigericin, as shown by DNA labeling studies.
Area of Science:
- Cell Biology
- Molecular Biology
- Toxicology
Context:
- Antibiotic administration can impact cellular processes.
- Cellular responses to chemical agents vary.
- Macronuclear DNA content is a key indicator of cell cycle progression.
Purpose:
- To investigate the effect of antibiotics on macronuclear DNA content.
- To compare the toxicity of nigericin and epinigericin.
- To analyze DNA synthesis activity post-antibiotic exposure.
Summary:
- Antibiotics induced an increase in macronuclear DNA content, linked to DNA synthesis in phase S2.
- Larger cells exhibited higher DNA content and extended generation times.
- Autoradiography confirmed increased DNA labeling with nigericin (46%) versus epinigericin (37%), indicating lower epinigericin toxicity.
Impact:
- Provides insights into antibiotic-induced cellular changes.
- Highlights differential toxicity between related compounds.
- Informs understanding of cell cycle regulation under chemical stress.
