Summary
Techniques that track individual enzymes or DNA molecules to reveal dynamics hidden in bulk experiments.
In depth
Optical tweezers, magnetic tweezers and single-molecule FRET watch one polymerase or helicase at work, revealing pausing, stepping and heterogeneity. Findings include the stepping of kinesin and the rotation of ATP synthase.
By looking at individual molecules, researchers avoid averaging and see steps, pauses, rare intermediates and differences between molecules that ensembles hide. Examples include watching RNA polymerase transcribe in real time, motors such as kinesin walking in 8 nm steps, ATP synthase rotating, and DNA being unwound by helicase one base pair at a time.
Methods include total internal reflection fluorescence microscopy, atomic force microscopy, nanopore sequencing (where DNA passes a pore and changes current), and super-resolution imaging. Nanopore and single-molecule real-time sequencing read long DNA and RNA molecules, with direct detection of modifications.
Example: single-molecule FRET showed that the ribosome fluctuates between conformations during translocation.
Frequently asked questions
What is Single-Molecule Biology?
Techniques that track individual enzymes or DNA molecules to reveal dynamics hidden in bulk experiments.
Which area of biology covers Single-Molecule Biology, and how advanced is it?
Single-Molecule Biology is one of the 52 topics in Molecular Biology. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include RNA Processing, Gene Expression, Homologous Recombination.
Can you give an example of Single-Molecule Biology?
Single-molecule tracking showed transcription factors bind DNA for only seconds.
What should I learn before Single-Molecule Biology?
Work through the Beginner topics in Molecular Biology first, such as Central Dogma, DNA Replication, Base Pairing, then return to Single-Molecule Biology. Advanced topics assume the Intermediate vocabulary.
What topics are related to Single-Molecule Biology?
The closest topics to Single-Molecule Biology are RNA Processing, Gene Expression, Homologous Recombination, Mediator Complex. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Single-Molecule Biology?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Single-Molecule Biology. To practise the whole of Molecular Biology, use the Molecular Biology quiz.
How is Single-Molecule Biology different from RNA Processing?
Single-Molecule Biology: Techniques that track individual enzymes or DNA molecules to reveal dynamics hidden in bulk experiments. RNA Processing: In eukaryotes, pre-mRNA gets a 5 prime cap, a poly-A tail and has introns spliced out. Read both side by side and note what each one explains.
How should I study Single-Molecule Biology step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with RNA Processing and explain the difference aloud. Finally, take the Molecular Biology quiz and come back to this page for any question you miss.