Twisted states of Bacillus subtilis macrofibers reflect structural states of the cell wall.
AUTOR(ES)
Mendelson, N H
RESUMO
Static and dynamic studies of helical Bacillus subtilis macrofibers reveal that a spectrum of twisted states exists ranging from tight left-handed structures with twist equal to approximately equal to 40 left turns per mm to tight right-handed structures with twist equal to 57 right turns per mm. In the lytic-deficient strain FJ7 , twist varies as a function of growth temperature above or below 39 degrees C, where there is zero twist. The relationship between the temperature (below 39 degrees C) at which right-hand structures are produced to the time it takes for them to begin the inversion process in which they become left-handed following transfer to 48 degrees C reveals that structures with less twist are more rapidly converted to left-handedness than are those with higher values of twist. The initial response of live macrofibers to digestion by lysozyme consists of "relaxation" motions in which the twist of both left- and right-handed structures changes towards the right-hand end of the spectrum. The rate of relaxation is approximately equal to 5-fold higher at the left-hand end than at the right-hand end. These findings suggest that cell wall polymers can assume a range of structural states during helical growth and that these determine the quantitative aspects of macrofiber shape as well as the sensitivity of walls to attack by lysozyme.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=345549Documentos Relacionados
- Structural differentiation of the Bacillus subtilis 168 cell wall.
- Chemical basis for selectivity of metal ions by the Bacillus subtilis cell wall.
- Genetic control of a structural polymer of the Neurospora crassa cell wall.
- Deconstructing the Cell Wall.
- Inversion of helix orientation in Bacillus subtilis macrofibers.