scholarly journals Nucleoids Dynamic in Escherichia coli: A Growth Phase Dependent Process

1970 ◽  
Vol 23 (2) ◽  
pp. 81-88 ◽  
Author(s):  
Ali Azam Talukder ◽  
M Anwar Hossain ◽  
Mamoru Yamada ◽  
Akira Ishihama
Keyword(s):  
Escherichia Coli ◽  
Stationary Phase ◽  
Gene Silencing ◽  
Cell Survival ◽  
Growth Phase ◽  
Genomic Dna ◽  
Bacterial Dna ◽  
Escherichia Coli Cells ◽  
Dna Organization ◽  
Nucleoid Proteins

Bacterial DNA compacts in nucleoid bodies. The organization of nucleoid body depends on the association of genomic DNA with a numbers of histone-like proteins. The relax nucleoids organization in rapidly growing Escherichia coli cells associate with six major proteins, Fis, HU, Hfq, H-NS, StpA and IHF, but at stationary phase the nucleoids further tightly pack with Dps. The final steps of compact nucleoids formation occurs with association of MukBEF complex - a bacterial condensin. The change of nucleoid proteins composition in stationary phase accompanies compact DNA organization and genes silencing. Thus, compact nucleoid organization and gene silencing may be crucial for cell survival in stationary phase.Keywords: Escherichia coli, Nucleoid body, Nucleoid proteins, Nucleoid compaction, CondensinDOI: http://dx.doi.org/10.3329/bjm.v23i2.867 Bangladesh J Microbiol, Volume 23, Number 2, December 2006, pp 81-88

scholarly journals The Chromosomal Toxin Gene yafQ Is a Determinant of Multidrug Tolerance for Escherichia coli Growing in a Biofilm

2009 ◽  
Vol 53 (6) ◽  
pp. 2253-2258 ◽  
Author(s):  
Joe J. Harrison ◽  
William D. Wade ◽  
Sarah Akierman ◽  
Caterina Vacchi-Suzzi ◽  
Carol A. Stremick ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Stationary Phase ◽  
Cell Survival ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Cell Counting ◽  
Confocal Laser ◽  
Toxin Gene ◽  
Persister Cells ◽  
E Coli

ABSTRACT Escherichia coli is refractory to elevated doses of antibiotics when it is growing in a biofilm, and this is potentially due to high numbers of multidrug-tolerant persister cells in the surface-adherent population. Previously, the chromosomal toxin-antitoxin loci hipBA and relBE have been linked to the frequency at which persister cells occur in E. coli populations. In the present study, we focused on the dinJ-yafQ-encoded toxin-antitoxin system and hypothesized that deletion of the toxin gene yafQ might influence cell survival in antibiotic-exposed biofilms. By using confocal laser scanning microscopy and viable cell counting, it was determined that a ΔyafQ mutant produced biofilms with a structure and a cell density equivalent to those of the parental strain. In-depth susceptibility testing identified that relative to wild-type E. coli, the ΔyafQ strain had up to a ∼2,400-fold decrease in cell survival after the biofilms were exposed to bactericidal concentrations of cefazolin or tobramycin. Corresponding to these data, controlled overexpression of yafQ from a high-copy-number plasmid resulted in up to a ∼10,000-fold increase in the number of biofilm cells surviving exposure to these bactericidal drugs. In contrast, neither the inactivation nor the overexpression of yafQ affected the tolerance of biofilms to doxycycline or rifampin (rifampicin). Furthermore, deletion of yafQ did not affect the tolerance of stationary-phase planktonic cells to any of the antibacterials tested. These results suggest that yafQ mediates the tolerance of E. coli biofilms to multiple but specific antibiotics; moreover, our data imply that this cellular pathway for persistence is likely different from that of multidrug-tolerant cells in stationary-phase planktonic cell cultures.

scholarly journals Structural Change of DNA Induced by Nucleoid Proteins: Growth Phase-Specific Fis and Stationary Phase-Specific Dps

2013 ◽  
Vol 105 (4) ◽  
pp. 1037-1044 ◽  
Author(s):  
Yuko T. Sato ◽  
Shun Watanabe ◽  
Takahiro Kenmotsu ◽  
Masatoshi Ichikawa ◽  
Yuko Yoshikawa ◽  
...  
Keyword(s):  
Structural Change ◽  
Stationary Phase ◽  
Growth Phase ◽  
Nucleoid Proteins

SlyD-dependent nickel delivery limits maturation of [NiFe]-hydrogenases in late-stationary phase Escherichia coli cells

Metallomics ◽  
2015 ◽  
Vol 7 (4) ◽  
pp. 683-690 ◽  
Author(s):  
Constanze Pinske ◽  
Frank Sargent ◽  
R. Gary Sawers
Keyword(s):  
Escherichia Coli ◽  
Stationary Phase ◽  
Late Stationary Phase ◽  
E Coli ◽  
Escherichia Coli Cells

The metallochaperone SlyD is essential for nickel delivery to hydrogenase in stationary phaseE. colicells.

scholarly journals DNA cytosine methylation at the lexA promoter of Escherichia coli is stationary phase specific

2021 ◽  
Author(s):  
Elizabeth B Lewis ◽  
Edwin Chen ◽  
Matthew J Culyba
Keyword(s):  
Escherichia Coli ◽  
Stationary Phase ◽  
Cytosine Methylation ◽  
Sos Response ◽  
Phase Growth ◽  
Bacterial Dna ◽  
Cytosine Methyltransferase ◽  
Lexa Binding ◽  
The Impact ◽  
Dna Damage Response Pathway

Abstract The bacterial DNA damage response pathway (SOS response) is composed of a network of genes regulated by a single transcriptional repressor, LexA. The lexA promoter, itself, contains two LexA operators, enabling negative feedback. In Escherichia coli, the downstream operator contains a conserved DNA cytosine methyltransferase (Dcm) site that is predicted to be methylated to 5-methylcytosine (5mC) specifically during stationary phase growth, suggesting a regulatory role for DNA methylation in the SOS response. To test this, we quantified 5mC at the lexA locus, and then examined the effect of LexA on Dcm activity, as well as the impact of this 5mC mark on LexA binding, lexA transcription, and SOS response induction. We found that 5mC at the lexA promoter is specific to stationary phase growth, but that it does not affect lexA expression. Our data support a model where LexA binding at the promoter inhibits Dcm activity without an effect on the SOS regulon.

Comparison of the Local Concentration of the HU Protein for Particular Regions of Genomic DNA in Escherichia coli Cells in Vivo

2005 ◽  
Vol 39 (4) ◽  
pp. 585-592 ◽  
Author(s):  
O. V. Preobrajenskaya ◽  
E. S. Starodubova ◽  
V. L. Karpov ◽  
J. Rouviere-Yaniv
Keyword(s):  
Escherichia Coli ◽  
Genomic Dna ◽  
Local Concentration ◽  
Hu Protein ◽  
Escherichia Coli Cells

scholarly journals Global Role for ClpP-Containing Proteases in Stationary-Phase Adaptation of Escherichia coli

2003 ◽  
Vol 185 (1) ◽  
pp. 115-125 ◽  
Author(s):  
Dieter Weichart ◽  
Nadine Querfurth ◽  
Mathias Dreger ◽  
Regine Hengge-Aronis
Keyword(s):  
Escherichia Coli ◽  
Stationary Phase ◽  
Growth Phase ◽  
Proteome Analysis ◽  
Resting Cells ◽  
Wild Type ◽  
Late Stationary Phase ◽  
E Coli ◽  
In The Wild ◽  
Dps Protein

ABSTRACT To elucidate the involvement of proteolysis in the regulation of stationary-phase adaptation, the clpA, clpX, and clpP protease mutants of Escherichia coli were subjected to proteome analysis during growth and during carbon starvation. For most of the growth-phase-regulated proteins detected on our gels, the clpA, clpX, or clpP mutant failed to mount the growth-phase regulation found in the wild type. For example, in the clpP and clpA mutant cultures, the Dps protein, the WrbA protein, and the periplasmic lysine-arginine-ornithine binding protein ArgT did not display the induction typical for late-stationary-phase wild-type cells. On the other hand, in the protease mutants, a number of proteins accumulated to a higher degree than in the wild type, especially in late stationary phase. The proteins affected in this manner include the LeuA, TrxB, GdhA, GlnA, and MetK proteins and alkyl hydroperoxide reductase (AhpC). These proteins may be directly degraded by ClpAP or ClpXP, respectively, or their expression could be modulated by a protease-dependent mechanism. From our data we conclude that the levels of most major growth-phase-regulated proteins in E. coli are at some point controlled by the activity of at least one of the ClpP, ClpA, and ClpX proteins. Cultures of the strains lacking functional ClpP or ClpX also displayed a more rapid loss of viability during extended stationary phase than the wild type. Therefore, regulation by proteolysis seems to be more important, especially in resting cells, than previously suspected.

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