scholarly journals codY and pdhA Expression Is Induced in Staphylococcus epidermidis Biofilm and Planktonic Populations With Higher Proportions of Viable but Non-Culturable Cells

2021 ◽  
Vol 11 ◽  
Author(s):  
Vânia Gaio ◽  
Nathalie Lopes ◽  
Nuno Cerca ◽  
Angela França
Keyword(s):  
Staphylococcus Epidermidis ◽  
Physiological Condition ◽  
Genetic Manipulation ◽  
Physiological State ◽  
Vbnc State ◽  
Mutant Strains ◽  
Strain Dependent ◽  
Is Strain

Staphylococcus epidermidis biofilm cells can enter a physiological state known as viable but non-culturable (VBNC), where, despite being alive, they do not grow in conventional laboratory media. As such, the presence of VBNC cells impacts the diagnosis of S. epidermidis biofilm-associated infections. Previous transcriptomics analysis of S. epidermidis strain 9142 biofilms with higher proportions of VBNC cells suggested that the genes pdhA, codY and mazEF could be involved in the induction of the VBNC state. However, it was previously demonstrated that VBNC induction is strain-dependent. To properly assess the role of these genes in VBNC induction, the construction of mutant strains is necessary. Thus, herein, we assessed if VBNC cells could be induced in strain 1457, a strain amenable to genetic manipulation, and if the previously identified genes were involved in the modulation of the VBNC state in this strain. Furthermore, we evaluated the formation of VBNC cells on planktonic cultures. Our results showed that despite being commonly associated with biofilms, the proportion of VBNC cells can be modulated in both biofilm and planktonic cultures and that the expression of codY and pdhA was upregulated under VBNC inducing conditions in both phenotypes. Overall, our study revealed that the formation of VBNC cells in S. epidermidis is independent of the mode of growth and that the genes codY and pdhA seem to be relevant for the regulation of this physiological condition.

scholarly journals Physiological state of reused brewing yeast

2013 ◽  
Vol 31 (No. 3) ◽  
pp. 264-269 ◽  
Author(s):  
E. Kordialik-Bogacka ◽  
A. Diowksz
Keyword(s):  
Yeast Strain ◽  
Significant Variation ◽  
Physiological Condition ◽  
Physiological State ◽  
Physiological Characteristics ◽  
Yeast Culture ◽  
Brewing Yeast ◽  
Flavour Compounds ◽  
The Impact ◽  
Is Strain

In brewing, yeast may be reused many times. A number of yeast repitchings differs significantly among the breweries. Adjusting the number of times a strain may be serially repitched is of great importance for quality and consistency of final products. The fermentative and physiological characteristics of the yeast culture used in successive laboratory scale fermentations were determined. Yeast physiological state was assessed by the measurement of the levels of intracellular carbohydrates. In our investigation there were not any detectable changes in yeast capacity to ferment. No significant variation in the production of flavour compounds was found either. However, intracellular glycogen and trehalose contents were dependant on the yeast strain, generation number and wort gravity. Nevertheless, an alteration in the yeast physiological condition during serial repitchings occurred in a different mode than in previous studies confirming that the impact of serial repitchings is strain and medium dependent to a large extent.  

Adhesion of Escherichia coli, Citrobacter freundii and Klebsiella pneumoniae isolated from milk: consequence on the efficiency of sanitation procedures

2003 ◽  
Vol 47 (5) ◽  
pp. 225-231 ◽  
Author(s):  
C. Faille ◽  
F. Fontaine ◽  
C. Lelièvre ◽  
T. Bénézech
Keyword(s):  
Essential Role ◽  
Physiological State ◽  
Organic Matrix ◽  
Similar Increase ◽  
E Coli ◽  
Biofilm Development ◽  
Biofilm Structure ◽  
Cleaning And Disinfection ◽  
Strain Dependent

The effects of adhesion and of biofilm development on the efficiency of cleaning and disinfection procedures were investigated on three strains belonging to the E. coli, C. freundii and K. pneumoniae species, which were able to raise more or less complex biofilms. Resistance to a rinsing procedure was strain dependent but not related to the biofilm structure: E. coli was poorly adherent although embedded in an organic matrix. Conversely, a similar increase in the heat- and disinfectant-resistance was observed, regardless of the complexity of the biofilm (more or less significant organic matrix). These results suggested the essential role of the bacterial physiological state in resistance to sanitation procedures.

scholarly journals Contribution of the ATP-Dependent Protease ClpCP to the Autolysis and Virulence of Streptococcus pneumoniae

2005 ◽  
Vol 73 (2) ◽  
pp. 730-740 ◽  
Author(s):  
Yasser Musa Ibrahim ◽  
Alison R. Kerr ◽  
Nuno A. Silva ◽  
Tim J. Mitchell
Keyword(s):  
Oxidative Stress ◽  
Streptococcus Pneumoniae ◽  
Elevated Temperature ◽  
Stress Resistance ◽  
Pneumococcal Disease ◽  
Pathogenic Bacteria ◽  
Strain Dependent ◽  
Is Strain

ABSTRACT The ATP-dependent caseinolytic proteases (Clp) are fundamental for stress tolerance and virulence in many pathogenic bacteria. The role of ClpC in the autolysis and virulence of Streptococcus pneumoniae is controversial. In this study, we tested the role of ClpC in a number of S. pneumoniae strains and found that the contribution of ClpC to autolysis is strain dependent. ClpC is required for the release of autolysin A and pneumolysin in serotype 2 S. pneumoniae strain D39. In vivo, ClpC is required for the growth of the pneumococcus in the lungs and blood in a murine model of disease, but it does not affect the overall outcome of pneumococcal disease. We also report the requirement of ClpP for the growth at elevated temperature and virulence of serotype 4 strain TIGR4 and confirm its contribution to the thermotolerance, oxidative stress resistance, and virulence of D39.

STEROID HORMONE METABOLISM IN RESPONSIVE TISSUES IN VITRO

1971 ◽  
Vol 68 (1_Suppl) ◽  
pp. S279-S294 ◽  
Author(s):  
Paul Robel
Keyword(s):  
Steroid Hormone ◽  
Physiological Activity ◽  
Physiological State ◽  
Target Cells ◽  
Target Tissue ◽  
Hormone Metabolism ◽  
Metabolizing Enzymes ◽  
Relationship Of

ABSTRACT Of the information available on steroid hormone metabolism in responsive tissues, only that relating hormone metabolism to physiological activity is reviewed, i. e. metabolite activity in isolated in vitro systems, binding of metabolites to target tissue receptors, specific steroid hormone metabolizing enzymes and relationship of hormone metabolism to target organ physiological state. Further, evidence is presented in the androgen field, demonstrating 5α-reduced metabolites, formed inside the target cells, as active compounds. This has led to a consideration of testosterone as a »prehormone«. The possibility that similar events take place in tissues responding to progesterone is discussed. Finally, the role of hormone metabolism in the regulation of hormone availability and/or renewal in target cells is discussed. In this context, reference is made to the potential role of plasma binding proteins and cytosol receptors.

Stages of the formation of temporary and permanent occlusion and the impact of early tooth extraction on the dentition state. Literature review

2019 ◽  
pp. 22-24
Author(s):  
G.A. Murachueva ◽  
I.M. Rasulov ◽  
S.G. Gusenov
Keyword(s):  
Literature Review ◽  
Temporomandibular Joint ◽  
Tooth Extraction ◽  
Physiological State ◽  
Review Of The Literature ◽  
Full Development ◽  
Permanent Occlusion ◽  
The Impact

A review of the literature on the stages of the formation of temporary and permanent occlusion has been performed. This stages play an important role not only for the full development of the maxillofacial apparatus, temporomandibular joint, but also the whole organism. The role of early tooth extraction in the formation of the physiological state of the dentoalveolar system is considered. The conclusion is drawn about the need for a deeper study of this problem in the structure of general dental morbidity.

scholarly journals Mouse model of panic disorder: Vulnerability to early environmental instability is strain‐dependent

2021 ◽  
Author(s):  
Alessandra Luchetti ◽  
Matteo Di Segni ◽  
Diego Andolina ◽  
Rossella Ventura ◽  
Marco Battaglia ◽  
...  
Keyword(s):  
Panic Disorder ◽  
Mouse Model ◽  
Environmental Instability ◽  
Strain Dependent ◽  
Is Strain
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