Related Experiment Video

Updated: May 7, 2026

Monitoring Protein-Ligand Interactions in Human Cells by Real-Time Quantitative In-Cell NMR using a High Cell Density Bioreactor
10:25

Monitoring Protein-Ligand Interactions in Human Cells by Real-Time Quantitative In-Cell NMR using a High Cell Density Bioreactor

Published on: March 9, 2021

Fate of pup inside the Mycobacterium proteasome studied by in-cell NMR

Andres Y Maldonado1, David S Burz, Sergey Reverdatto

  • 1Department of Chemistry, State University of New York at Albany, Albany, New York, United States of America.

Plos One
|September 17, 2013
PubMed

Insights

Mycobacterium tuberculosis proteasome activity is key for virulence. Researchers used in-cell NMR to show how Pup-GGQ interacts with Mpa and the proteasome core particle, revealing a mechanism for Pup protein fate control.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Structural Biology

Background:

  • The Mycobacterium tuberculosis proteasome is essential for bacterial virulence and immune evasion.
  • The prokaryotic ubiquitin-like protein (Pup) system targets proteins for degradation by the proteasome.

Purpose of the Study:

  • To investigate the in-cell interactions of Pup-GGQ, a Pup precursor, with the mycobacterial proteasome components.
  • To elucidate the mechanism by which Pup-GGQ interacts with the mycobacterial proteasomal ATPase (Mpa) and proteasome core particle (CP).

Main Methods:

  • Utilized STINT-NMR (Strain-Promoted In-line NMR), an in-cell NMR technique.
  • Analyzed interactions at amino acid residue resolution within living bacterial cells.

Main Results:

  • Pup-GGQ exhibits weak interaction with Mpa via its C-terminal region in the absence of the proteasome CP.
  • Both N-terminal and C-terminal regions of Pup-GGQ bind strongly to Mpa when Mpa and proteasome CP are present.
  • Demonstrated that Pup-GGQ is not a substrate for proteasomal degradation.

Conclusions:

  • The binding dynamics of Mpa to the proteasome CP, influenced by Pup-GGQ, suggest a regulatory mechanism for Pup protein fate.
  • This study provides insights into the molecular mechanisms governing protein degradation and virulence in Mycobacterium tuberculosis.

More Related Videos

Assays for the Degradation of Misfolded Proteins in Cells10:56

Assays for the Degradation of Misfolded Proteins in Cells

Published on: August 28, 2016

4D Imaging of Protein Aggregation in Live Cells08:59

4D Imaging of Protein Aggregation in Live Cells

Published on: April 5, 2013

Related Concept Videos

The Proteasome Structure01:17

The 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...
Termination of Translation01:44

Termination of Translation

The large ribosomal subunit has several important structures essential to translation. These include the peptidyl transferase center (PTC) - which is the site where the peptide bond is formed - and a large, internal, water-filled tube through which the nascent polypeptide moves. This latter structure is called the Peptide Exit Tunnel, and it begins at the PTC and spans the body of the large ribosomal subunit. During translation, as the nascent polypeptide chain is synthesized, it passes through...
Translocation of Proteins into the Mitochondria01:19

Translocation of Proteins into the Mitochondria

Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...