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ActA is a dimer.

P Mourrain·I Lasa·A Gautreau·E Gouin·A Pugsley·P Cossart
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Abstract

ActA, a surface protein of Listeria monocytogenes, is able to induce continuous actin polymerization at the rear of the bacterium, in the cytosol of the infected cells. Its N-terminal domain is sufficient to induce actin tail formation and movement. Here, we demonstrate, using the yeast two-hybrid system, that the N-terminal domain of ActA may form homodimers. By using chemical cross-linking to explore the possibility that ActA could be a multimer on the surface of the bacteria, we show that ActA is a dimer. Cross-linking experiments on various L. monocytogenes strains expressing different ActA variants demonstrated that the region spanning amino acids 97-126, and previously identified as critical for actin tail formation, is also critical for dimer formation. A model of actin polymerization by L. monocytogenes, involving the ActA dimer, is presented.

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Bacterial ProteinsDimerizationListeria monocytogenesMembrane ProteinsRecombinant ProteinsSaccharomyces cerevisiaeJournal ArticleResearch Support, Non-U.S. Gov't

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P Mourrain, I Lasa, A Gautreau, E Gouin, A Pugsley, P Cossart. 1997-09-16. ActA is a dimer.. https://doi.org/10.1073/pnas.94.19.10034

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