Myosin and actin from Escherichia coli K12 C600

J Biochem. 1978 Dec;84(6):1453-8. doi: 10.1093/oxfordjournals.jbchem.a132268.


Myosin-like protein and actin-like protein from E. coli formed filaments very similar in structure to those of myosin and actin from skeletal muscle. At 0.2 M KCl, a large number of "thick filaments" of uniform size (about 0.6-0.7 micron long and about 20 nm wide) was present. These thick filaments aggregated as the KCl concentration decreased to less than 0.2 M. Filaments of actin-like protein were decorated with muscle heavy meromyosin, showing "arrowheads". The arrowhead structure disappeared in the presence of ATP. A mixture of E. coli myosin-like protein and rabbit skeletal actin exhibited a gelation phenomenon on the additon of ATP. The phenomenon was reversible and showed ATP specificity. However, the gelation phenomenon was not observed with the mixture of E. coli actin-like protein and E. coli myosin-like protein. These results provide compelling evidence that the E. coli myosin-like protein and actin-like protein we isolated are essentially identical to myosin and actin, respectively.

MeSH terms

  • Actins* / metabolism
  • Adenosine Triphosphatases / metabolism
  • Escherichia coli / enzymology*
  • Microscopy, Electron
  • Myosins* / metabolism
  • Spectrophotometry, Ultraviolet


  • Actins
  • Adenosine Triphosphatases
  • Myosins