scholarly journals Expression Profiles and Physiological Roles of Two Types of Molecular Chaperonins from the Hyperthermophilic Archaeon Thermococcus kodakarensis

2008 ◽  
Vol 74 (23) ◽  
pp. 7306-7312 ◽  
Author(s):  
Shinsuke Fujiwara ◽  
Ryohei Aki ◽  
Masaya Yoshida ◽  
Hiroki Higashibata ◽  
Tadayuki Imanaka ◽  
...  
Keyword(s):  
Cell Growth ◽  
Stationary Phase ◽  
Stationary Phases ◽  
Expression Profiles ◽  
Mrna Level ◽  
Temperature Adaptation ◽  
Logarithmic Phase ◽  
Temperature Dependent ◽  
Independent Manner ◽  
Thermococcus Kodakarensis

ABSTRACT Thermococcus kodakarensis possesses two chaperonins, CpkA and CpkB, and their expression is induced by the downshift and upshift, respectively, of the cell cultivation temperature. The expression levels of the chaperonins were examined by using specific antibodies at various cell growth temperatures in the logarithmic and stationary phases. At 60°C, CpkA was highly expressed in both the logarithmic and stationary phases; however, CpkB was not expressed in either phase. At 85°C, CpkA and CpkB were expressed in both phases; however, the CpkA level was decreased in the stationary phase. At 93°C, CpkA was expressed only in the logarithmic phase and not in the stationary phase. In contrast, CpkB was highly expressed in both phases. The results of reverse transcription-PCR experiments showed the same growth phase- and temperature-dependent profiles as observed in immunoblot analyses, indicating that the expression of cpkA and cpkB is regulated at the mRNA level. The cpkA or cpkB gene disruptant was then constructed, and its growth profile was monitored. The cpkA disruptant showed poor cell growth at 60°C but no significant defects at 85°C and 93°C. On the other hand, cpkB disruption led to growth defects at 93°C but no significant defects at 60°C and 85°C. These data indicate that CpkA and CpkB are necessary for cell growth at lower and higher temperatures, respectively. The logarithmic-phase-dependent expression of CpkA at 93°C suggested that CpkA participates in initial cell growth in addition to lower-temperature adaptation. Promoter mapping and quantitative analyses using the Phr (Pyrococcus heat-shock regulator) gene disruptant revealed that temperature-dependent expression was achieved in a Phr-independent manner.

scholarly journals Combination of flucloxacillin and gentamicin inhibits toxic shock syndrome toxin 1 production by Staphylococcus aureus in both logarithmic and stationary phases of growth.

1997 ◽  
Vol 41 (8) ◽  
pp. 1682-1685 ◽  
Author(s):  
P van Langevelde ◽  
J T van Dissel ◽  
C J Meurs ◽  
J Renz ◽  
P H Groeneveld
Keyword(s):  
Staphylococcus Aureus ◽  
Stationary Phase ◽  
Bacterial Growth ◽  
Toxic Shock Syndrome ◽  
Stationary Phases ◽  
Logarithmic Phase ◽  
Toxic Shock ◽  
Viable Bacteria ◽  
Static Effect ◽  
Toxic Shock Syndrome Toxin

Production of exotoxins by staphylococci and streptococci may lead to the development of toxic shock syndrome (TSS). Because clindamycin inhibits exotoxin production, its use has been advocated for the treatment of TSS. However, the bacteriostatic action of clindamycin might be a disadvantage for the treatment of overwhelming infections. We investigated the effects of flucloxacillin and gentamicin on exotoxin production, because incubation with these antibiotics combines bactericidal action with protein synthesis inhibition. Staphylococcus aureus during the logarithmic and stationary phases of growth was incubated with either clindamycin, flucloxacillin, or a combination of flucloxacillin and gentamicin at concentrations of 2 or 10 times the MIC. In logarithmic-phase cultures clindamycin had a static effect on bacterial growth. After incubation with flucloxacillin, either alone or in combination with gentamicin, a rapid and large reduction in the number of viable bacteria was demonstrated. In stationary-phase cultures none of the antibiotics significantly changed the number of viable bacteria. TSS toxin 1 (TSST-1) production during logarithmic-phase growth was inhibited by > or =95% by all antibiotics. In stationary-phase cultures, clindamycin, flucloxacillin, and the combination of flucloxacillin and gentamicin inhibited TSST-1 production by 95, 30, and 75%, respectively, compared with the level of exotoxin production in the controls. The present results indicate that clindamycin inhibits TSST-1 production and exerts bacteriostatic activity in both bacterial growth phases. Because the combination of flucloxacillin and gentamicin combines the inhibition of exotoxin production with high bactericidal activity at least in logarithmic-phase cultures, it should be considered an alternative to clindamycin for the treatment of exotoxin-mediated diseases, especially in patients with overwhelming infections.

scholarly journals Ribosomal Protein S1 Specifically Binds to the 5′ Untranslated Region of the Pseudomonas aeruginosa Stationary-Phase Sigma Factor rpoS mRNA in the Logarithmic Phase of Growth

2004 ◽  
Vol 186 (15) ◽  
pp. 4903-4909 ◽  
Author(s):  
Milica Ševo ◽  
Emanuele Buratti ◽  
Vittorio Venturi
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Stationary Phase ◽  
Ribosomal Protein ◽  
Sigma Factor ◽  
Untranslated Region ◽  
Stationary Phases ◽  
Translation Regulation ◽  
Logarithmic Phase ◽  
Ribosomal Protein S1 ◽  
Sigma Factor Rpos

ABSTRACT The rpoS gene encodes the stationary-phase sigma factor (RpoS or σs), which was identified in several gram-negative bacteria as a central regulator controlling the expression of genes involved in cell survival in response to cessation of growth (stationary phase) and providing cross-protection against various stresses. In Pseudomonas aeruginosa, the levels of σs increase dramatically at the onset of the stationary phase and are regulated at the transcriptional and posttranscriptional levels. The P. aeruginosa rpoS gene is transcribed as a monocistronic rpoS mRNA transcript comprised of an unusually long 373-bp 5′ untranslated region (5′ UTR). In this study, the 5′ UTR and total protein extracts from P. aeruginosa logarithmic and stationary phases of growth were used in order to investigate the protein-RNA interactions that may modulate the translational process. It was observed that a 69-kDa protein, which corresponded to ribosomal protein S1, preferentially binds the 5′ UTR of the rpoS mRNA in the logarithmic phase and not in the stationary phase. This is the first report of a protein-rpoS mRNA 5′ UTR interaction in P. aeruginosa, and the possible involvement of protein S1 in translation regulation of rpoS is discussed.

scholarly journals Is the cellular and molecular machinery docile in the stationary phase of Escherichia coli?

2015 ◽  
Vol 43 (2) ◽  
pp. 168-171 ◽  
Author(s):  
Parul Mehta ◽  
Goran Jovanovic ◽  
Liming Ying ◽  
Martin Buck
Keyword(s):  
Stationary Phase ◽  
Single Molecule ◽  
Growth Phase ◽  
Bound States ◽  
Cell Envelope ◽  
Stationary Phases ◽  
Negative Regulator ◽  
Logarithmic Phase ◽  
Bacterial Cells ◽  
Highly Active

The bacterial cell envelope retains a highly dense cytoplasm. The properties of the cytoplasm change with the metabolic state of the cell, the logarithmic phase (log) being highly active and the stationary phase metabolically much slower. Under the differing growth phases, many different types of stress mechanisms are activated in order to maintain cellular integrity. One such response in enterobacteria is the phage shock protein (Psp) response that enables adaptation to the inner membrane (IM) stress. The Psp system consists of a transcriptional activator PspF, negative regulator PspA, signal sensors PspBC, with PspA and PspG acting as effectors. The single molecule imaging of the PspF showed the existence of dynamic communication between the nucleoid-bound states of PspF and membrane via negative regulator PspA and PspBC sensors. The movement of proteins in the cytoplasm of bacterial cells is often by passive diffusion. It is plausible that the dynamics of the biomolecules differs with the state of the cytoplasm depending on the growth phase. Therefore, the Psp response proteins might encounter the densely packed glass-like properties of the cytoplasm in the stationary phase, which can influence their cellular dynamics and function. By comparing the properties of the log and stationary phases, we find that the dynamics of PspF are influenced by the growth phase and may be controlled by the changes in the cytoplasmic fluidity.

scholarly journals The rye Mutants Identify a Role for Ssn/Srb Proteins of the RNA Polymerase II Holoenzyme During Stationary Phase Entry in Saccharomyces cerevisiae

Genetics ◽  
2001 ◽  
Vol 157 (1) ◽  
pp. 17-26 ◽  
Author(s):  
Ya-Wen Chang ◽  
Susie C Howard ◽  
Yelena V Budovskaya ◽  
Jasper Rine ◽  
Paul K Herman
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Growth ◽  
Rna Polymerase ◽  
Stationary Phase ◽  
Yeast Cell ◽  
Rna Polymerase Ii ◽  
Transcriptional Response ◽  
Nutrient Deprivation ◽  
Ras Signaling ◽  
Rna Polymerase Ii Holoenzyme

Abstract Saccharomyces cerevisiae cells enter into a distinct resting state, known as stationary phase, in response to specific types of nutrient deprivation. We have identified a collection of mutants that exhibited a defective transcriptional response to nutrient limitation and failed to enter into a normal stationary phase. These rye mutants were isolated on the basis of defects in the regulation of YGP1 expression. In wild-type cells, YGP1 levels increased during the growth arrest caused by nutrient deprivation or inactivation of the Ras signaling pathway. In contrast, the levels of YGP1 and related genes were significantly elevated in the rye mutants during log phase growth. The rye defects were not specific to this YGP1 response as these mutants also exhibited multiple defects in stationary phase properties, including an inability to survive periods of prolonged starvation. These data indicated that the RYE genes might encode important regulators of yeast cell growth. Interestingly, three of the RYE genes encoded the Ssn/Srb proteins, Srb9p, Srb10p, and Srb11p, which are associated with the RNA polymerase II holoenzyme. Thus, the RNA polymerase II holoenzyme may be a target of the signaling pathways responsible for coordinating yeast cell growth with nutrient availability.

Carboxylated cyclofructan 6 as a hydrolytically stable high efficiency stationary phase for hydrophilic interaction liquid chromatography and mixed mode separations

2016 ◽  
Vol 8 (31) ◽  
pp. 6038-6045 ◽  
Author(s):  
Yadi Wang ◽  
M. Farooq Wahab ◽  
Zachary S. Breitbach ◽  
Daniel W. Armstrong
Keyword(s):  
Liquid Chromatography ◽  
Benzoic Acid ◽  
Stationary Phase ◽  
Mixed Mode ◽  
High Efficiency ◽  
Stationary Phases ◽  
Hydrophilic Interaction Liquid Chromatography ◽  
Hydrophilic Interaction

Stationary phases composed of native cyclofructan 6 (CF6) and benzoic acid modified CF6 were synthesized and evaluated for hydrophilic interaction liquid chromatography (HILIC).

scholarly journals Bacterial Cellulose as a Substrate for Microbial Cell Culture

2014 ◽  
Vol 80 (6) ◽  
pp. 1926-1932 ◽  
Author(s):  
Na Yin ◽  
Thiago M. A. Santos ◽  
George K. Auer ◽  
John A. Crooks ◽  
Piercen M. Oliver ◽  
...  
Keyword(s):  
Cell Culture ◽  
Cell Growth ◽  
Physicochemical Properties ◽  
Stationary Phase ◽  
Bacterial Cellulose ◽  
Growth Rates ◽  
Bacterial Cell ◽  
Acetobacter Xylinum ◽  
Primary Factor ◽  
Nutrient Diffusion

ABSTRACTBacterial cellulose (BC) has a range of structural and physicochemical properties that make it a particularly useful material for the culture of bacteria. We studied the growth of 14 genera of bacteria on BC substrates produced byAcetobacter xylinumand compared the results to growth on the commercially available biopolymers agar, gellan, and xanthan. We demonstrate that BC produces rates of bacterial cell growth that typically exceed those on the commercial biopolymers and yields cultures with higher titers of cells at stationary phase. The morphology of the cells did not change during growth on BC. The rates of nutrient diffusion in BC being higher than those in other biopolymers is likely a primary factor that leads to higher growth rates. Collectively, our results suggest that the use of BC may open new avenues in microbiology by facilitating bacterial cell culture and isolation.

scholarly journals Phenotypic and clonal stability of antigen-inexperienced memory-like T cells across the genetic background, hygienic status, and aging

2020 ◽  
Author(s):  
Alena Moudra ◽  
Veronika Niederlova ◽  
Jiri Novotny ◽  
Lucie Schmiedova ◽  
Jan Kubovciak ◽  
...  
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
Genetic Background ◽  
Expression Profiles ◽  
Bacterial Colonization ◽  
Gene Expression Profiles ◽  
Inbred Strains ◽  
Microbial Colonization ◽  
Independent Manner ◽  
Different Genetic Background

AbstractAntigen-inexperienced memory-like T (AIMT) cells are functionally unique T cells representing one of the two largest subsets of murine CD8+ T cells. However, differences between laboratory inbred strains, insufficient data from germ-free mice, a complete lack of data from feral mice, and unclear relationship between AIMT cells formation during aging represent major barriers for better understanding of their biology. We performed a thorough characterization of AIMT cells from mice of different genetic background, age, and hygienic status by flow cytometry and multi-omics approaches including analyses of gene expression, TCR repertoire, and microbial colonization. Our data showed that AIMT cells are steadily present in mice independently of their genetic background and hygienic status. Despite differences in their gene expression profiles, young and aged AIMT cells originate from identical clones. We identified that CD122 discriminates two major subsets of AIMT cells in a strain-independent manner. Whereas thymic CD122LOW AIMT cells (innate memory) prevail only in young animals with high thymic IL-4 production, peripheral CD122HIGH AIMT cells (virtual memory) dominate in aged mice. Co-housing with feral mice changed the bacterial colonization of laboratory strains, but had only minimal effects on the CD8+ T-cell compartment including AIMT cells.

scholarly journals Kovats retention index-boiling point relationship of 2-phenyl-2-alkyl-acetonitriles on stationary phases of different polarity

2005 ◽  
Vol 11 (2) ◽  
pp. 55-58 ◽  
Author(s):  
Dusan Mijin ◽  
Dusan Antonovic
Keyword(s):  
Stationary Phase ◽  
Retention Index ◽  
Boiling Point ◽  
Chemical Potential ◽  
Stationary Phases ◽  
Kovats Retention Index ◽  
Standard Chemical Potential ◽  
Relationship Of ◽  
Kováts Retention Index ◽  
Methylene Group

Linear and reciprocial Kovats retention index-boiling point relationships known from the literature were used to study the Kovats retention index-boiling point dependence of 2-phenyl-2-alkylacetonitriles on stationary phases of different polarity (OV-17, OV-210 and OV-225). The standard chemical potential of the partitioning of one methylene group of an n-alkane for the stationary phase was calculated and compared with available literature data.

scholarly journals Induction of the synthesis of an additional family of long-chain dolichols in the yeast Saccharomyces cerevisiae. Effect of starvation and ageing.

2002 ◽  
Vol 49 (3) ◽  
pp. 781-787 ◽  
Author(s):  
Anna Szkopinska ◽  
Ewa Swiezewska ◽  
Joanna Rytka
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Stationary Phase ◽  
Yeast Cells ◽  
Logarithmic Phase ◽  
Cellular Membranes ◽  
Yeast Saccharomyces Cerevisiae ◽  
Chemical Changes ◽  
Physico Chemical ◽  
Long Chain

The yeast Saccharomyces cerevisiae strain W303 synthesizes in the early logarithmic phase of growth dolichols of 14-18 isoprene residues. The analysis of the polyisoprenoids present in the stationary phase revealed an additional family which proved to be also dolichols but of 19-24 isoprene residues, constituting 39% of the total dolichols. The transfer of early logarithmic phase cells to a starvation medium lacking glucose or nitrogen resulted in the synthesis of the longer chain dolichols. The additional family of dolichols represented 13.8% and 10.3% of total dolichols in the glucose and nitrogen deficient media, respectively. The level of dolichols in yeast cells increased with the age of the cultures. Since both families of dolichols are present in stationary phase cells we postulate that the longer chain dolichols may be responsible for the physico-chemical changes in cellular membranes allowing yeast cells to adapt to nutrient deficient conditions to maintain long-term viability.

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