L. monocytogenes-induced actin assembly requires the actA gene product, a surface protein

Cell. 1992 Feb 7;68(3):521-31. doi: 10.1016/0092-8674(92)90188-i.


The intracellular pathogenic bacterium L. monocytogenes can spread directly from cell to cell without leaving the cytoplasm. The mechanism of this movement, generated through bacterially induced actin polymerization, is not understood. By analyzing an avirulent Tn917-lac mutant defective for actin polymerization, we have identified a bacterial component involved in this process. The transposon had inserted in actA, the second gene of an operon. Gene disruption of downstream genes and transformation of the mutant strain with actA showed that the actA gene encodes a surface protein necessary for bacterially induced actin assembly. Our results indicate that it is a 610 amino acid protein with an apparent molecular weight of 90 kd.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3 Cells
  • Actins / biosynthesis*
  • Amino Acid Sequence
  • Animals
  • Bacterial Proteins / analysis
  • Bacterial Proteins / genetics*
  • Base Sequence
  • Cloning, Molecular
  • Endopeptidases / genetics
  • Genes, Bacterial*
  • Listeria monocytogenes / genetics*
  • Listeria monocytogenes / pathogenicity
  • Membrane Proteins / analysis
  • Membrane Proteins / genetics*
  • Mice
  • Molecular Sequence Data
  • Oligonucleotides
  • Phospholipases / genetics
  • Virulence / genetics


  • Actins
  • Bacterial Proteins
  • Membrane Proteins
  • Oligonucleotides
  • actA protein, Listeria monocytogenes
  • Phospholipases
  • Endopeptidases