Ear­lier elec­tron micro­scope stud­ies of iso­lated Lis­te­ria comet tails iden­ti­fied dif­fer­ent pop­u­la­tions of actin fil­a­ments ori­ented both oblique and par­al­lel to the comet axis (Sechi et al., 1997). But the intact tails were too thick to resolve details of the struc­ture close to the bac­terium. How­ever, where tails became splayed on the elec­tron micro­scope sup­port film indi­vid­ual fil­a­ments could be resolved.  Re-analysis of these images revealed branch junc­tions like those seen in comet tails of bac­ulovirus.

Negatively-stained comet tail of iso­lated pro­tru­sion induced by Lis­te­ria in a PtK2 cell. One region of the tail was splayed out on the sup­port film

Enlarged region of Lis­te­ria comet tail show­ing branch junc­tions encir­cled.

Related Pub­li­ca­tions

  •  Sechi AS, Wehland J, Small JV. The iso­lated comet tail pseudopodium of Lis­te­ria mono­cy­to­genes: a tail of two actin fil­a­ment pop­u­la­tions, long and axial and short and ran­dom. J Cell Biol. 1997 Apr 7;137(1):15567. PDF