Related Experiment Video
Updated: May 24, 2026
07:58
In-vitro Reconstitution of Bacterial Ubiquitination and VCP/p97-mediated Elimination
Published on: January 2, 2026
Pupylation: proteasomal targeting by a protein modifier in bacteria
Kristin E Burns1, K Heran Darwin
1Institute for Genetics, University of Cologne, Cologne, Germany.
Methods in Molecular Biology (Clifton, N.J.)
|February 22, 2012
Summary
Researchers adapted ubiquitin modification methods to study pupylation, a distinct protein modification process in mycobacteria. This enables the identification and analysis of pupylated proteins and their modifiers.
Area of Science:
- Molecular Biology
- Biochemistry
- Microbiology
Background:
- Mycobacteria utilize a proteasome for protein degradation.
- This degradation involves covalent modification of target proteins with prokaryotic ubiquitin-like protein (Pup), a process called pupylation.
- Pupylation is functionally similar but structurally and enzymatically distinct from ubiquitination.
Purpose of the Study:
- To adapt existing ubiquitin modification research methods for studying pupylation in mycobacteria.
- To develop reagents for isolating, identifying, and analyzing pupylated proteins.
- To enable further research into pupylation and related posttranslational modifications in prokaryotes.
Main Methods:
- Adaptation of established methods from the ubiquitin modification field.
- Production of specific reagents for pupylated protein analysis.
- Application of these methods to mycobacterial systems.
Main Results:
- Successful adaptation of ubiquitin research techniques for pupylation studies.
- Development of tools to isolate and identify pupylated proteins.
- Demonstration of the utility of these methods for mycobacterial research.
Conclusions:
- The adapted methods provide a valuable toolkit for studying pupylation in mycobacteria.
- These techniques can be modified to investigate pupylated proteins in other Pup-bearing bacteria.
- The approach facilitates the identification of novel posttranslational modifiers in prokaryotes.
Related Concept Videos
02:04Covalently Linked Protein Regulators
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.
01:13The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
02:18The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
01:26Bacterial Protein Maturation
Bacterial protein maturation is a tightly regulated process that ensures newly synthesized polypeptides achieve correct functional conformations. This maturation involves a series of modifications, folding events, and quality control steps, often assisted by specialized chaperone proteins.N-Terminal ModificationsThe maturation of bacterial polypeptides begins cotranslationally as the polypeptide exits the ribosome. The first amino acid, N-formylmethionine (fMet), is typically modified at the...
02:58Regulated Protein Degradation
It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
01:17The Proteasome Structure
The ubiquitin-proteasome pathway is a well-known mechanism utilized by eukaryotic cells to remove cytoplasmic proteins that are misfolded, damaged, or no longer needed. In this pathway, the protein that needs to be eliminated undergoes a process called ubiquitination, where a chain of ubiquitin molecules is attached to the 48th lysine residue of the target protein. This ubiquitin modification helps the proteasome distinguish between a target protein and a healthy protein.
The proteasome is an...
The proteasome is an...