1887

Abstract

Summary: macrofibres exposed to lysozyme underwent characteristic rotations, termed relaxation motions, in which their twist changed. Intact macrofibres and macrofibre fragments devoid of loop ends responded in the same way. Macrofibre strains for which the helix hand is temperature-dependent and also those of fixed-hand (both left and right) underwent initial relaxation motions towards the right-hand end of the twist spectrum, the only exception being those in which the initial twist state was at or near the right-hand maximum. Often when the initial relaxation motions were completed immediately before structure breakdown the macrofibres underwent one or a few rotations in the opposite direction (towards the left-hand end of the twist spectrum). Crude autolysin extract obtained from wild-type also caused macrofibre relaxation motions at pH 5·6 but at pH 8·0 macrofibre breakdown occurred as a result of septa) cleavage. This resulted in the release of helically shaped individual cellular filaments. These findings suggest that strain in the cell wall associated with helical shape was dependent on the integrity of the glycan backbone rather than peptide cross-bridges. In contrast, cleavage of peptide cross-bridges apparently was instrumental in the cell separation process. Left-and right-hand macrofibres, when exposed to lysozyme, exhibited different rates of relaxation, breakdown of fibre structure and protoplast formation. Similarly, the rate of macrofibre breakdown during the lag between temperature shift and inversion reflected the replacement of septal wall material by that of a new conformation corresponding to the new helix hand. The difference in the rates of protoplast formation indicates asymmetry in the overall rate of cleavage by lysozyme which may reflect the activity of left-twist protein(s).

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-132-8-2377
1986-08-01
2021-10-27
Loading full text...

Full text loading...

/deliver/fulltext/micro/132/8/mic-132-8-2377.html?itemId=/content/journal/micro/10.1099/00221287-132-8-2377&mimeType=html&fmt=ahah

References

  1. Brown W. C., Young F. E. 1970; Dynamic interaction between cell wall polymers, extracellular protease and autolytic enzymes. Biochemical and Biophysical Research Communications 38:546–568
    [Google Scholar]
  2. Favre D. 1984 Comportments des macrofibres de Bacillus subtilis en fonction de la temperature et leur correlation avec la structure et la reorganisation de la paroi bacterienne PhD thesis University of Lau-sanne; Switzerland. (In French.):
    [Google Scholar]
  3. Favlle D., Karamata D., Mendelson N. H. 1985a; Temperature-pulse-induced “memory” in Bacillus subtilis macrofibers and a role for protein(s) in the left-handed twist state. Journal of Bacteriology 164:1141–1145
    [Google Scholar]
  4. Favre D., , Thwaites J. J., Mendelson N. H. 1985b; Kinetic studies of temperature-induced helix hand inversion in Bacillus subtilis macrofibers. Journal of Bacteriology 164:1136–1140
    [Google Scholar]
  5. Fein J. E., Rogers H.J. 1976; Autolytic enzyme-deficient mutants of Bacillus subtilis. Journal of Bacteriology 127:1427–1442
    [Google Scholar]
  6. Hobot J. A., Carlemalm E., Villiger W., Kellenberger E. 1984; Periplasmic gel: new concept resulting from the reinvestigation of bacterial cell envelope ultrastructure by new methods. Journal of Bacteriology 160:143–152
    [Google Scholar]
  7. Imoto T., Johnson L. N., North D. C., Phillips D. C., Rupley J. A. 1972; Vertebrate lysozyme. In The Enzymes vol. 7: pp. 665–868 Edited by Boyer P. D. New York: Academic Press;
    [Google Scholar]
  8. Koch A. L., Doyle R. J. 1985; Inside-to-outside growth and turnover of the wall ofthe Gram-positive rod. Journal of Theoretical Biology 117:137–157
    [Google Scholar]
  9. Mendelson N. H. 1976; Helical growth of Bacillus subtilis: a new model of cell growth. Proceedings of the National Academy of Sciences ofthe United States of America 73:1740–1744
    [Google Scholar]
  10. Mendelson N. H. 1978; Helical Bacillus subtilis macrofibers: morphogenesis of a bacterial multicellular macroorganism. Proceedings of the National Academy of Sciences of the United States of America 75:2478–2482
    [Google Scholar]
  11. Mendelson N. H. 1982; Dynamics of Bacillus subtilis helical macrofiber morphogenesis: writhing, folding, close packing and contraction. Journal of Bacteriology 151:438–449
    [Google Scholar]
  12. Mendelson N. H., Favre D., Thwaites J. J. 1984; Twisted states of Bacillus subtilis macrofibers reflect structural states of the cell wall. Proceedings of the National Academy ofSciences of the United States of America 81:3562–3566
    [Google Scholar]
  13. Mendelson N. H., Thwaites J. J., Favre D., Surana U., Briehl M. M., Wolfe A. J. 1985; Factors contributing to helical shape determination and maintenance in Bacillus subtilis macrofibres. Annales de l’Institut Pasteur/Microbiologie 136S:99–103
    [Google Scholar]
  14. Pooley H. M. 1976; Layered distribution according to age within the cell wall of Bacillus subtilis. Journal of Bacteriology 125:1139–1147
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-132-8-2377
Loading
/content/journal/micro/10.1099/00221287-132-8-2377
Loading

Data & Media loading...

Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error