Previous Article | Next Article ![]()
Applied and Environmental Microbiology, November 2001, p. 5171-5178, Vol. 67, No. 11
Laboratory of Food Microbiology, Wageningen
University,1 and Wageningen Centre for
Food Sciences (WCFS),3 Wageningen, and
Microbial Ingredients Section, NIZO Food Research,
Ede,2 The Netherlands
Received 27 April 2001/Accepted 28 August 2001
Members of the group of 7-kDa cold-shock proteins (CSPs) are the
proteins with the highest level of induction upon cold shock in
the lactic acid bacterium Lactococcus lactis MG1363. By
using double-crossover recombination, two L. lactis strains
were generated in which genes encoding CSPs are disrupted: L. lactis NZ9000
0099-2240/01/$04.00+0 DOI: 10.1128/AEM.67.11.5171-5178.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
Cold Shock Proteins of Lactococcus
lactis MG1363 Are Involved in Cryoprotection and in the Production
of Cold-Induced Proteins
and
AB lacks the tandemly orientated
cspA and cspB genes, and NZ9000
ABE lacks
cspA, cspB, and cspE. Both strains showed no
differences in growth at normal and at low temperatures compared to
that of the wild-type strain, L. lactis NZ9000.
Two-dimensional gel electrophoresis showed that upon disruption of the
cspAB genes, the production of remaining CspE at low
temperature increased, and upon disruption of cspA, cspB,
and cspE, the production of CspD at normal growth temperatures increased. Northern blot analysis showed that control is
most likely at the transcriptional level. Furthermore, it was established by a proteomics approach that some (non-7-kDa) cold-induced proteins (CIPs) are not cold induced in the csp-lacking
strains, among others the histon-like protein HslA and the signal
transduction protein LlrC. This supports earlier observations (J. A. Wouters, M. Mailhes, F. M. Rombouts, W. M. De Vos, O. P. Kuipers, and T. Abee, Appl. Environ. Microbiol. 66:3756-3763, 2000).
that the CSPs of L. lactis might be directly involved in
the production of some CIPs upon low-temperature exposure. Remarkably,
the adaptive response to freezing by prior exposure to 10°C was
significantly reduced in strain NZ9000
ABE but not in strain
NZ9000
AB compared to results with wild-type strain NZ9000,
indicating a notable involvement of CspE in cryoprotection.
*
Corresponding author. Mailing address: Laboratory of
Food Microbiology, Wageningen University, Bomenweg 2, 6703 HD
Wageningen, The Netherlands. Phone: 31-317-484981. Fax: 31-317-484978. E-mail: jeroen.wouters{at}micro.fdsci.wau.nl.
Present address: Department of Genetics, Groningen Biomolecular
Sciences and Biotechnology institute (GBB), University of Groningen,
9750 AA Haren, The Netherlands.
This article has been cited by other articles:
| J. Bacteriol. | Microbiol. Mol. Biol. Rev. | Eukaryot. Cell | All ASM Journals |
|---|