Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2021 Jun 17;49(12):6804–6816. doi: 10.1093/nar/gkab493

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© The Author(s) 2021. Published by Oxford University Press on behalf of Nucleic Acids Research.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.

PMC Copyright notice

Figure 3. — More than one DnaB helicase are frequently present at the replication fork. (A) Illustration of the rolling-circle replication assay with DnaB₆(red) preloaded on the DNA prior to introducing the replication solution. Replication is monitored in real time by flow stretching the replicating DNA products by hydrodynamic force. (B) (Top) Representative kymograph of preloaded DnaB₆(red) moving with the fork during rolling-circle replication. (Bottom) Overlay of the DnaB₆(red) and SYTOX Orange-stained DNA (green) kymographs shows the helicase molecule moving with the replication fork at the tip of the DNA product. (C) Distributions of DnaB helicase stoichiometry at the fork in the absence of DnaB₆(red) in solution (magenta; n = 32) and in the presence of DnaB₆(red) in solution (purple; n = 33). The black lines represent Gaussian fits to the data. (D) Illustration of the in-solution assay, where DnaB₆(red) is preloaded and also included at 2 nM in the replication solution. (E) Representative kymograph showing the DnaB₆(red) signal at the fork when DnaB₆(red) is present in solution. (F) Number of DnaB₆(red) as a function of time for the kymograph in (E) showing the fluctuation in DnaB helicase stoichiometry during the course of replication, where steps are detected by change-point analysis (47–49).