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From 'I' to 'L' and back again: the odyssey of membrane-bound M13 protein

Werner L Vos1, Petr V Nazarov, Rob B M Koehorst

  • 1Department of Biology, National University of Ireland Maynooth, County Kildare, Ireland.

Trends in Biochemical Sciences
|April 14, 2009
PubMed

Insights

The M13 phage major coat protein

Area of Science:

  • Structural biology
  • Virology
  • Biochemistry

Background:

  • The M13 phage major coat protein functions as both a membrane protein and a phage coat component.
  • Previous structural models for the membrane-bound state varied between I-shaped and L-shaped conformations.

Purpose of the Study:

  • To investigate the structure of the M13 phage major coat protein in its membrane-bound state.
  • To compare the membrane-bound structure with the known phage-bound structure.

Main Methods:

  • Utilized site-directed labeling techniques.
  • Studied the coat protein under conditions mimicking its in vivo membrane-bound state.

Main Results:

  • The membrane-bound structure of the M13 phage major coat protein was determined to be I-shaped.
  • This structure is similar to the previously established phage-bound conformation.

Conclusions:

  • The M13 phage major coat protein maintains a consistent I-shaped alpha-helical structure across its life cycle.
  • Recent studies confirm the I-shaped model for the membrane-bound state, resolving previous structural ambiguities.

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