Previous Article | Next Article ![]()
Journal of Bacteriology, November 1998, p. 5947-5953, Vol. 180, No. 22
Department of Genetics, Groningen
Biomolecular Sciences and Biotechnology Institute, University of
Groningen, 9751 NN Haren, The Netherlands
Received 20 April 1998/Accepted 21 August 1998
The autolysin AcmA of Lactococcus lactis was shown to
be degraded by the extracellular lactococcal proteinase PrtP.
Autolysis, as evidenced by reduction in optical density of a
stationary-phase culture and concomitant release of intracellular
proteins, was greatly reduced when L. lactis MG1363 cells
expressed the cell wall-anchored lactococcal proteinase PrtP of the
PI-type caseinolytic specificity (PI). On the other hand, lactococcal
strains that did not produce the proteinase showed a high level of
autolysis, which was also observed when the cells produced the secreted
form of PI or a cell wall-anchored proteinase with PIII-type
specificity. Autolysis was also increased when MG1363 expressed the
cell wall-anchored hybrid PI/PIII-type proteinase PIac. Zymographic
analysis of AcmA activity during stationary phase showed that AcmA was
quickly degraded by PI and much more slowly by PrtP proteinases with
PIII-type and intermediate specificities. Autolysis of L. lactis by AcmA was influenced by the specificity, amount, and
location of the lactococcal proteinase. No autolysis was observed when
the various proteinases were expressed in an L. lactis acmA
deletion mutant, indicating that PrtP itself did not cause lysis of
cells. The chain length of a strain was significantly shortened when
the strain expressed a cell wall-anchored active proteinase.
0021-9193/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.
Autolysis of Lactococcus lactis Is
Influenced by Proteolysis
*
Corresponding author. Mailing address: Department of
Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands. Phone: 31-50-3632111. Fax: 31-50-3632348. E-mail:
Kokj{at}Biol.Rug.NL.
This article has been cited by other articles:
| Appl. Environ. Microbiol. | Infect. Immun. | Eukaryot. Cell |
|---|---|---|
| Mol. Cell. Biol. | J. Virol. | Microbiol. Mol. Biol. Rev. |
| ALL ASM JOURNALS |