Related Experiment Video
Updated: Jun 10, 2026

Visualization and Quantitative Analysis of Genotoxin-Induced PARP1/PARP2 Activation in Cells Using a Fluorescent Fusion Protein-Based Reporter
Published on: April 17, 2026
A novel replicative enzyme encoded by the linear Arthrobacter plasmid pAL1.
Stephan Kolkenbrock1, Bianca Naumann, Michael Hippler
1Institute of Molecular Microbiology and Biotechnology, Westfalian Wilhelms-University Münster, Corrensstrasse 3, D-48149 Münster, Germany.
The pAL1.101 protein from Arthrobacter nitroguajacolicus Rü61a may function as a linear plasmid replicase. This protein exhibits DNA topoisomerase, helicase, and DNA polymerase activities, crucial for plasmid replication.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Arthrobacter nitroguajacolicus Rü61a harbors the linear plasmid pAL1, essential for 2-methylquinoline degradation.
- Linear plasmids in actinomycetes share features like terminal inverted repeats and covalently attached terminal proteins (TPpAL1).
Purpose of the Study:
- To investigate the function of the pAL1.101 protein, encoded by the linear plasmid pAL1.
- To elucidate the enzymatic activities of the pAL1.101 protein and its potential role in plasmid replication.
Main Methods:
- Bioinformatic analysis of the pAL1.101 protein sequence to predict functional domains.
- Purification of recombinant pAL1.101 protein.
- Enzyme assays to determine DNA topoisomerase, helicase, and DNA polymerase activities.
Main Results:
- Bioinformatic analysis suggested zinc finger, topoisomerase-primase, and helicase domains in pAL1.101.
- The purified pAL1.101 protein catalyzed deoxycytidylation of TPpAL1 on specific DNA templates.
- Enzyme assays confirmed DNA topoisomerase, helicase, and DNA- and protein-primed DNA polymerase activities.
Conclusions:
- The pAL1.101 protein possesses multiple enzymatic activities essential for DNA replication.
- These findings suggest that the pAL1.101 protein acts as a replicase for the linear plasmid pAL1.
More Related Videos
Related Concept Videos
Plasmids
Replication in Prokaryotes
Many Proteins Work Together to Replicate the Chromosome
Replication is coordinated and carried out by a host of specialized...
Replication in Prokaryotes
Replication in Prokaryotes
The Replisome
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...

