An abundant cell-surface polypeptide is required for swimming by the nonflagellated marine cyanobacterium Synechococcus

Proc Natl Acad Sci U S A. 1996 Jun 25;93(13):6504-9. doi: 10.1073/pnas.93.13.6504.


Certain marine unicellular cyanobacteria of the genus Synechococcus exhibit a unique and mysterious form of motility characterized by the ability to swim in liquid in the absence of flagella. An abundant cell-surface-associated polypeptide that is required for swimming motility by Synechococcus sp. strain WH8102 has been identified, and the gene encoding it, swmA, has been cloned and sequenced. The predicted SwmA protein contains a number of Ca2+-binding motifs as well as several potential N-glycosylation sites. Insertional inactivation of swmA in Synechococcus sp. strain WH8102 results in a loss of the ability to translocate, although the mutant strain, Swm-1, generates torque. This suggests that SwmA functions in the generation of thrust.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins*
  • Base Sequence
  • Calcium-Binding Proteins / genetics
  • Calcium-Binding Proteins / pharmacology*
  • Cloning, Molecular
  • Cyanobacteria / chemistry
  • Cyanobacteria / genetics
  • Cyanobacteria / physiology*
  • DNA, Bacterial
  • Escherichia coli / genetics
  • Locomotion
  • Membrane Proteins / physiology*
  • Molecular Sequence Data
  • Peptides / physiology*
  • Sequence Homology, Amino Acid


  • Bacterial Proteins
  • Calcium-Binding Proteins
  • DNA, Bacterial
  • Membrane Proteins
  • Peptides
  • SwmA protein, Synechococcus

Associated data

  • GENBANK/U48223