Related Experiment Video

Updated: Jun 28, 2026

Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein
09:39

Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein

Published on: April 21, 2015

Influenza A virus M1 protein structure probed by in situ limited proteolysis with bromelain

L V Kordyukova1, M V Serebryakova, V Y Polyakov

  • 1A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119991, Russia. kord@belozersky.msu.ru

Protein and Peptide Letters
|November 11, 2008
PubMed

Insights

Investigating the Influenza A virus matrix M1 protein's structure, this study used bromelain digestion to reveal fragmentation sites on the M1 protein surface. These sites offer new landmarks for 3D molecular modeling of the virus.

Area of Science:

  • Virology
  • Structural Biology
  • Biochemistry

Background:

  • Influenza A virus matrix M1 protein is essential for virus assembly and budding.
  • Previous X-ray crystallography resolved the N-terminal two-thirds of M1, but its overall 3D structure and membrane association remain unclear.

Purpose of the Study:

  • To assess the in situ structure of the M1 protein within influenza virions.
  • To identify potential sites on the M1 protein for 3D molecular modeling.

Main Methods:

  • Proteolytic digestion of influenza virions using bromelain.
  • Transmission electron microscopy to observe disruption of the viral lipid bilayer.
  • SDS-PAGE analysis combined with in-gel trypsin hydrolysis and MALDI-TOF mass spectrometry to analyze M1 protein fragmentation.

Main Results:

  • Bromelain digestion partially disrupted the lipid bilayer of glycoprotein-lacking subviral particles.
  • M1 protein fragmentation was observed within subviral particles.
  • Putative bromelain digestion sites were identified on the surface of the M1 protein globule.

Conclusions:

  • Proteolytic digestion with bromelain provides an effective method for in situ assessment of M1 protein structure.
  • Identified digestion sites can serve as valuable landmarks for future 3D molecular modeling of the influenza A virus M1 protein.

More Related Videos

A Fluorogenic Peptide Cleavage Assay to Screen for Proteolytic Activity: Applications for coronavirus spike protein activation07:53

A Fluorogenic Peptide Cleavage Assay to Screen for Proteolytic Activity: Applications for coronavirus spike protein activation

Published on: January 9, 2019

Identifying Caspases and their Motifs that Cleave Proteins During Influenza A Virus Infection08:16

Identifying Caspases and their Motifs that Cleave Proteins During Influenza A Virus Infection

Published on: July 21, 2022

Related Concept Videos

Leaky Scanning02:28

Leaky Scanning

During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA.  Marilyn Kozak discovered that the sequence RCCAUGG (where R stands for...
Influenza01:27

Influenza

Influenza is an acute, highly communicable viral disease that affects the respiratory tract and is responsible for seasonal epidemics worldwide. Influenza A is the most prevalent type associated with widespread outbreaks and is subtyped based on two surface glycoproteins: hemagglutinin (H) and neuraminidase (N), as in H1N1. These glycoproteins are essential for viral infectivity, transmission, and immune recognition. Transmission occurs primarily through respiratory droplets and contaminated...
Inhibitors Of Virion Release01:25

Inhibitors Of Virion Release

Viral replication and dissemination rely on efficient mechanisms for host cell entry, genome replication, assembly, and release. Influenza viruses, such as types A and B, are negative-sense single-stranded RNA viruses with a segmented genome, that depend on two critical surface glycoproteins to carry out these processes: hemagglutinin (HA) and neuraminidase (NA). HA initiates infection by binding to sialic acid residues on the surface of host epithelial cells, facilitating receptor-mediated...