A defect in cell wall recycling triggers autolysis during the stationary growth phase of Escherichia coli

ABSTRACT Transcription of an aqpZ-lac fusion in a single copy on the Escherichia coli chromosome increased as cells entered the stationary growth phase. This was true in a variety of media, and increased transcription in enriched medium required the RpoS sigma factor. Expression of the aqpZ-lac fusion was not affected by up- or downshifts in osmolality. Disruption of aqpZ had no detectable adverse effects.

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The CiaRH System of Streptococcus pneumoniae Prevents Lysis during Stress Induced by Treatment with Cell Wall Inhibitors and by Mutations in pbp2x Involved in β-Lactam Resistance

Journal of Bacteriology ◽

10.1128/jb.188.5.1959-1968.2006 ◽

2006 ◽

Vol 188 (5) ◽

pp. 1959-1968 ◽

Cited By ~ 65

Author(s):

Thorsten Mascher ◽

Manuel Heintz ◽

Dorothea Zähner ◽

Michelle Merai ◽

Regine Hakenbeck

Keyword(s):

Cell Wall ◽

Streptococcus Pneumoniae ◽

Growth Phase ◽

Point Mutations ◽

Normal Growth ◽

Stationary Growth Phase ◽

Clinical Isolates ◽

Loss Of Function ◽

Beta Lactam ◽

Stationary Growth

ABSTRACT The two-component signal-transducing system CiaRH of Streptococcus pneumoniae plays an important role during the development of beta-lactam resistance in laboratory mutants. We show here that a functional CiaRH system is required for survival under many different lysis-inducing conditions. Mutants with an activated CiaRH system were highly resistant to lysis induced by a wide variety of early and late cell wall inhibitors, such as cycloserine, bacitracin, and vancomycin, and were also less susceptible to these drugs. In contrast, loss-of-function CiaRH mutants were hypersusceptible to these drugs and were apparently unable to maintain a stationary growth phase in normal growth medium and under choline deprivation as well. Moreover, disruption of CiaR in penicillin-resistant mutants with an altered pbp2x gene encoding low-affinity PBP2x resulted in severe growth defects and rapid lysis. This phenotype was observed with pbp2x genes containing point mutations selected in the laboratory and with highly altered mosaic pbp2x genes from penicillin-resistant clinical isolates as well. This documents for the first time that PBP2x mutations required for development of beta-lactam resistance are functionally not neutral and are tolerated only in the presence of the CiaRH system. This might explain why cia mutations have not been observed in penicillin-resistant clinical isolates. The results document that the CiaRH system is required for maintenance of the stationary growth phase and for prevention of autolysis triggered under many different conditions, suggesting a major role for this system in ensuring cell wall integrity.

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The Stationary-Phase Sigma Factor σS Is Responsible for the Resistance of Escherichia coli Stationary-Phase Cells to mazEF-Mediated Cell Death

Journal of Bacteriology ◽

10.1128/jb.00011-09 ◽

2009 ◽

Vol 191 (9) ◽

pp. 3177-3182 ◽

Cited By ~ 8

Author(s):

Ilana Kolodkin-Gal ◽

Hanna Engelberg-Kulka

Keyword(s):

Escherichia Coli ◽

Cell Death ◽

Stationary Phase ◽

Growth Phase ◽

Sigma Factor ◽

Stationary Growth Phase ◽

Cellular Growth ◽

Oxygen Species ◽

Stationary Growth ◽

Gene Encoding

ABSTRACT Escherichia coli mazEF is a toxin-antitoxin gene module that mediates cell death during exponential-phase cellular growth through either reactive oxygen species (ROS)-dependent or ROS-independent pathways. Here, we found that the stationary-phase sigma factor σS was responsible for the resistance to mazEF-mediated cell death during stationary growth phase. Deletion of rpoS, the gene encoding σS from the bacterial chromosome, permitted mazEF-mediated cell death during stationary growth phase.

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Ribosome Modulation Factor: Stationary Growth Phase-Specific Inhibitor of Ribosome Functions from Escherichia coli

Biochemical and Biophysical Research Communications ◽

10.1006/bbrc.1995.2302 ◽

1995 ◽

Vol 214 (2) ◽

pp. 410-417 ◽

Cited By ~ 88

Author(s):

A. Wada ◽

K. Igarashi ◽

S. Yoshimura ◽

S. Aimoto ◽

A. Ishihama

Keyword(s):

Escherichia Coli ◽

Growth Phase ◽

Specific Inhibitor ◽

Stationary Growth Phase ◽

Stationary Growth ◽

Modulation Factor ◽

Ribosome Modulation Factor

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Conversion of Daidzein and Genistein by an Anaerobic Bacterium Newly Isolated from the Mouse Intestine

Applied and Environmental Microbiology ◽

10.1128/aem.00555-08 ◽

2008 ◽

Vol 74 (15) ◽

pp. 4847-4852 ◽

Cited By ~ 73

Author(s):

Anastasia Matthies ◽

Thomas Clavel ◽

Michael Gütschow ◽

Wolfram Engst ◽

Dirk Haller ◽

...

Keyword(s):

Stationary Phase ◽

Enzyme Induction ◽

Growth Phase ◽

Anaerobic Bacterium ◽

Stationary Growth Phase ◽

Gut Bacteria ◽

Soy Isoflavones ◽

Strictly Anaerobic ◽

Stationary Growth ◽

Mouse Intestine

ABSTRACT The metabolism of isoflavones by gut bacteria plays a key role in the availability and bioactivation of these compounds in the intestine. Daidzein and genistein are the most common dietary soy isoflavones. While daidzein conversion yielding equol has been known for some time, the corresponding formation of 5-hydroxy-equol from genistein has not been reported previously. We isolated a strictly anaerobic bacterium (Mt1B8) from the mouse intestine which converted daidzein via dihydrodaidzein to equol as well as genistein via dihydrogenistein to 5-hydroxy-equol. Strain Mt1B8 was a gram-positive, rod-shaped bacterium identified as a member of the Coriobacteriaceae. Strain Mt1B8 also transformed dihydrodaidzein and dihydrogenistein to equol and 5-hydroxy-equol, respectively. The conversion of daidzein, genistein, dihydrodaidzein, and dihydrogenistein in the stationary growth phase depended on preincubation with the corresponding isoflavonoid, indicating enzyme induction. Moreover, dihydrogenistein was transformed even more rapidly in the stationary phase when strain Mt1B8 was grown on either genistein or daidzein. Growing the cells on daidzein also enabled conversion of genistein. This suggests that the same enzymes are involved in the conversion of the two isoflavones.

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The extracellular proteome of Rhizobium etli CE3 in exponential and stationary growth phase

Proteome Science ◽

10.1186/1477-5956-8-51 ◽

2010 ◽

Vol 8 (1) ◽

pp. 51 ◽

Cited By ~ 18

Author(s):

Niurka Meneses ◽

Guillermo Mendoza-Hernández ◽

Sergio Encarnación

Keyword(s):

Growth Phase ◽

Stationary Growth Phase ◽

Rhizobium Etli ◽

Stationary Growth ◽

Extracellular Proteome

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Proteomic Study of the Exponential-Stationary Growth Phase Transition in the Haloarchaea Natrialba magadii and Haloferax volcanii

PROTEOMICS ◽

10.1002/pmic.201800116 ◽

2018 ◽

Vol 18 (14) ◽

pp. 1800116 ◽

Cited By ~ 3

Author(s):

Micaela Cerletti ◽

María Ines Giménez ◽

Christian Tröetschel ◽

Celeste D’ Alessandro ◽

Ansgar Poetsch ◽

...

Keyword(s):

Phase Transition ◽

Growth Phase ◽

Stationary Growth Phase ◽

Haloferax Volcanii ◽

Stationary Growth ◽

Proteomic Study ◽

Natrialba Magadii ◽

Growth Phase Transition

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Effect of Temperature on Growth and Alpha Toxin Production by Clostridium perfringens1

Journal of Food Protection ◽

10.4315/0362-028x-42.11.848 ◽

1979 ◽

Vol 42 (11) ◽

pp. 848-851 ◽

Cited By ~ 4

Author(s):

Y. PARK ◽

E. M. MIKOLAJCIK

Keyword(s):

Growth Phase ◽

Incubation Temperature ◽

Ground Beef ◽

Population Level ◽

Toxin Production ◽

Stationary Growth Phase ◽

Effect Of Temperature ◽

Alpha Toxin ◽

Stationary Growth ◽

Incubation Temperatures

Growth and alpha toxin production by a strain of Clostridium perfringens was determined in Thioglycollate medium, beef broth with ground beef, and beef broth with ground beef and soy protein. Incubation temperatures ranged from 15 to 50 C. In Thioglycollate medium, maximum alpha toxin production occurred at 35 C and was 40 times greater than that observed at 45 C. However, generation time and maximum population were approximately the same at 35 and 45 C. At 15 C, a two log cycle reduction in viable counts occurred within 6 h. Irrespective of incubation temperature, alpha toxin levels in Thioglycollate medium declined as the incubation period was extended beyond the stationary growth phase. In the beef broth with ground beef system which was studied at 35 C only, the organism grew slower and produced less toxin than in Thioglycollate medium. The amount of alpha toxin detected was influenced to a greater extent by the incubation time and temperature, the holding time beyond the stationary growth phase, and the growth medium than by the population level of C. perfringens.

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