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Molecular characteristics of OmpF-like porins from pathogenic Yersinia

K V Guzev1, M P Isaeva, O D Novikova

  • 1Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch, Russian Academy of Sciences, Vladivostok, 690022, Russia. kotok@piboc.dvo.ru

Biochemistry. Biokhimiia
|November 8, 2005
PubMed

Insights

Researchers cloned and analyzed OmpF-like porins from Yersinia bacteria. These outer membrane proteins show high homology to each other and possess structural features typical for porins, crucial for bacterial function.

Area of Science:

  • Microbiology
  • Structural Biology
  • Biochemistry

Background:

  • Nonspecific pore-forming proteins, or porins, are essential components of Gram-negative bacterial outer membranes.
  • Porins facilitate the diffusion of low-molecular-weight compounds across the membrane.

Purpose of the Study:

  • To clone and determine the nucleotide sequences of OmpF-like porins from Yersinia pseudotuberculosis (YPS) and Yersinia enterocolitica (YE).
  • To analyze the homology, molecular characteristics, and secondary structure of these Yersinia porins.

Main Methods:

  • Nucleotide sequencing of OmpF-like porins.
  • Calculation of molecular weights (MW) and isoelectric points (IEP).
  • Multiple sequence alignment and predictive methods for secondary structure analysis.

Main Results:

  • Cloned and sequenced OmpF-like porins from YPS and YE, with calculated MW and IEP values matching experimental data.
  • Yersinia porins exhibit high homology (83-92%) to each other and moderate homology to Serratia marcescens OmpF (70%), but lower homology to E. coli OmpF (52-58%).
  • Secondary structure prediction revealed 16 beta-strands connected by loops, consistent with porin topology.

Conclusions:

  • OmpF-like porins from Yersinia share conserved structural features with other porins.
  • The identified structural characteristics, including transmembrane domains and external loops, are typical for OmpF porins.
  • These findings contribute to understanding the structure-function relationship of porins in pathogenic Yersinia species.

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