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bioRxiv · 10.1101/2021.03.18.436108

Specific protein-membrane interactions promote the export of metallo-β-lactamases via outer membrane vesicles

Lopez, C.·Prunotto, A.·Bahr, G.·Bonomo, R. A.·Gonzalez, L. J.·Dal Peraro, M.·Vila, A. J.
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Abstract

Outer membrane vesicles (OMVs) act as carriers of resistance determinants such as metallo-{beta}-lactamases. The metallo-{beta}-lactamase NDM-1 is present in OMVs produced by Gram-negative bacteria since it is a lipidated, membrane-anchored protein. The soluble domain of NDM-1 also forms electrostatic interactions with the membrane. Herein, we show that these interactions promote its export into OMVs produced by Escherichia coli. We report that favorable electrostatic protein-membrane interactions are also at work in the soluble enzyme IMP-1, while being absent in VIM-2. These interactions correlate with an enhanced secretion into OMVs of IMP-1 compared to VIM-2. Disruption of these interactions in NDM-1 and IMP-1 impairs export into vesicles, confirming their role in defining the protein cargo in OMVs. These results also indicate that export of metallo-{beta}-lactamases into vesicles in their active form is a common phenomenon that involves cargo selection based on molecular features.

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Lopez, C., Prunotto, A., Bahr, G., Bonomo, R. A., Gonzalez, L. J., Dal Peraro, M., Vila, A. J.. 2021-03-20. Specific protein-membrane interactions promote the export of metallo-β-lactamases via outer membrane vesicles. https://doi.org/10.1101/2021.03.18.436108

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