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Directed Protein Packaging within Outer Membrane Vesicles from Escherichia coli: Design, Production and Purification
10:21

Directed Protein Packaging within Outer Membrane Vesicles from Escherichia coli: Design, Production and Purification

Published on: November 16, 2016

[Membrane-bound proteases of ompT+ and ompT- Vibrio cholerae strains]

S N Kozlov, V B Nikolaev, E Iu Markov

    Zhurnal Mikrobiologii, Epidemiologii I Immunobiologii
    |June 29, 2013
    PubMed
    Abstract

    Insights

    Outer membranes of Vibrio cholerae strains, both ompT+ and ompT-, contain proteases. These proteases exhibit varying activities and sensitivities to inhibitors, suggesting potential roles in virulence.

    Area of Science:

    • Microbiology
    • Proteomics
    • Molecular Biology

    Context:

    • Vibrio cholerae, a Gram-negative bacterium, causes cholera, a severe diarrheal disease.
    • Outer membrane proteins (OMPs) play crucial roles in bacterial pathogenesis and interaction with the host.
    • The ompT gene encodes a protease that may contribute to V. cholerae virulence.

    Purpose:

    • To detect and characterize proteases in the outer membranes of ompT-positive (ompT+) and ompT-negative (ompT-) Vibrio cholerae strains.
    • To investigate the differences in protease profiles and activities between ompT+ and ompT- V. cholerae strains.
    • To assess the sensitivity of these proteases to specific inhibitors.

    Summary:

    • Outer membrane preparations from ompT+ and ompT- V. cholerae strains (O1 and O139 serogroups) were analyzed using SDS- and enzyme-electrophoresis.
    • Both ompT+ and ompT- strains exhibited protease activity against gelatin, casein, and protamine sulfate.
    • Protease activity was reduced by inhibitors like soy trypsin inhibitor (STI) and phenylmethylsulfonyl fluoride (PMSF), indicating the presence of serine proteases.
    • Up to three proteases were detected in ompT+ and ompT- V. cholerae outer membranes, with some potentially being ompT-like.

    Impact:

    • This study reveals the presence and diversity of proteases in the outer membrane of Vibrio cholerae, irrespective of ompT gene presence.
    • Understanding these proteases can provide insights into V. cholerae pathogenesis and potential therapeutic targets.
    • The findings contribute to the broader knowledge of bacterial outer membrane protein function and regulation.

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