Related Experiment Videos
DNA polymerase of a basidiomycete fungus, Coprinus cinereus
Abstract:
DNA polymerase activity was studied in Coprinus cinereus, a basidiomycete fungus. Only one from of the enzyme could be demonstrated, whether by affinity or ion-exchange chromatography; this enzyme had a molecular weight of 185000 on Sephadex G-200, and was inhibited by mercaptoethanol. Coprinus, a representative of the most advanced type of the filamentous fungi, resembles other eukaryotic micro-organisms in its lack of a mammalian beta-type DNA polymerase. The properties of the polymerase are compared with those of two other fungi, and found to resemble most closely the yeast polymerase A in Mg2+ requirements and template preference.
Insights
Researchers investigated DNA polymerase in the fungus Coprinus cinereus. This eukaryotic microorganism lacks mammalian beta-type DNA polymerase, showing similarities to yeast polymerase A.
Area of Science:
- Mycology
- Molecular Biology
- Biochemistry
Background:
- DNA polymerases are crucial enzymes for DNA replication and repair in all organisms.
- Fungal DNA polymerases exhibit diverse properties, reflecting evolutionary adaptations.
- Coprinus cinereus is a model basidiomycete fungus with complex filamentous structures.
Purpose of the Study:
- To characterize the DNA polymerase activity in Coprinus cinereus.
- To compare its enzymatic properties with those of other eukaryotic DNA polymerases.
- To understand the evolutionary relationships of fungal DNA polymerases.
Main Methods:
- Affinity chromatography
- Ion-exchange chromatography
- Sephadex G-200 gel filtration
- Enzyme inhibition assays
Main Results:
- A single form of DNA polymerase was isolated from Coprinus cinereus.
- The enzyme exhibited a molecular weight of 185,000 Da and was sensitive to mercaptoethanol inhibition.
- Coprinus DNA polymerase lacked homology to mammalian beta-type DNA polymerase.
- Enzymatic properties, including Mg2+ requirements and template preference, closely matched yeast polymerase A.
Conclusions:
- Coprinus cinereus possesses a unique DNA polymerase distinct from mammalian counterparts.
- The findings suggest conserved enzymatic characteristics among certain eukaryotic fungal DNA polymerases.
- This study contributes to the understanding of DNA replication machinery diversity in fungi.