Microcalorimetric assays for measuring cell growth and metabolic activity: Methodology and applications

Braissant, Olivier; Bachmann, Alexander; Bonkat, Gernot

doi:10.1016/j.ymeth.2014.10.009

Cited by 69 publications

(57 citation statements)

References 126 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The analytical capacity of the instrument could easily be adapted, depending on the needs of different drug manufacturers, as commercially available instruments have a sample capacity ranging from 1 up to 48 measuring slots (Braissant et al . , ). It must be noted, however, that some isothermal calorimeters used in research were built with up to 100 channels (Wadsö ).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

An alternative sterility assessment for parenteral drug products using isothermal microcalorimetry

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Discussionmentioning

confidence: 99%

“…In addition, collected heat flow curves were integrated and fitted using the Gompertz growth model (Braissant et al . , ). Thereby, additional descriptive parameters such as total heat, growth rate and lag phase duration could be extracted (Table ).…”

Section: Methodsmentioning

confidence: 99%

An alternative sterility assessment for parenteral drug products using isothermal microcalorimetry

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…By detection of less than a microwatt of heat flow, heat produced by microorganisms in relation to their metabolic activity and replication rates (ranging from 0.2-500uW) can be measured continuously and translated into a real-time electronic signal, reflecting growth-related heat flow patterns [13, 14]. …”

Section: Introductionmentioning

confidence: 99%

Growth Patterns of Clostridium difficile – Correlations with Strains, Binary Toxin and Disease Severity: A Prospective Cohort Study

et al. 2016

View full text Add to dashboard Cite

A broad spectrum of symptoms has been associated with C. difficile infection (CDI). Several studies indicate that toxin-production correlates with growth rates of C. difficile. This study aimed to correlate growth rates of C. difficile with disease severity and strain characteristics. From 01/2003 to 10/2011, strains from a prospective cohort of all inpatients with CDI at the University Hospital Basel, Switzerland were analyzed regarding binary toxin, presence of the tcdC deletion and ribotype. Isothermal microcalorimetry was performed to determine growth rates, quantified by the Gompertz function. Ordered logistic regression models were used to correlate disease severity with strain features and clinical characteristics. Among 199 patients, 31 (16%) were infected with binary toxin-producing strains, of which the tcdC gene-deletion nt117 was detected in 9 (4%). Disease severity was classified as mild in 130 patients (65.3%), as severe in 59 patients (29.7%) and as severe/complicated in 10 patients (5.0%). Growth rates were inversely associated with disease severity in univariable (OR 0.514, 95%CI 0.29–0.91, p = 0.023) and multivariable analyses (OR 0.51, 95%CI 0.26–0.97, p = 0.040). While none of the strain characteristics such as presence of the tcdC gene deletion or binary toxin predicted CDI severity, growth rates were inversely correlated with disease severity. Further investigations are needed to analyze growth-regulators and respective correlations with the level of toxin production in C. difficile, which may be important determinants of disease severity.

show abstract

“…It is also a universal, non-invasive, and non-destructive method used by many studies in recent years (Braissant et al 2015;Bricheux et al 2013;Carvalho et al 2013;Cirak et al 2003;Guo et al 2012;Kong et al 2012;Li et al 2014;Tim Cushnie and Lamb 2005;Xiao et al 2013;Zhang et al 2014). Among these studies, microcalorimetry has been used to evaluate the antibacterial activity of some compounds or medicinal plants (Bricheux et al 2013;Zhang et al 2014) and the toxicity of some toxic substances or heavy metals (Kong et al 2012;Li et al 2014), as well as monitoring special reactions (Carvalho et al 2013;Xiao et al 2013), etc.…”

Section: Introductionmentioning

confidence: 99%

Antibacterial evaluation of flavonoid compounds against E. coli by microcalorimetry and chemometrics

Kong

Yan

Xing

et al. 2015

Appl Microbiol Biotechnol

View full text Add to dashboard Cite

Fighting against multidrug-resistant bacteria requires reliable methods to evaluate the effect of antibacterial agents. As a universal, non-destructive, and highly sensitive tool, microcalorimetry has been used in many biological investigations to provide continuous real-time monitoring of the metabolic activity. This method, based on heat-flow output, was used to evaluate the influence of two flavonoid compounds (liquiritigenin and liquiritin) on Escherichia coli. Some crucial information, such as the thermogenic power-time curve and thermokinetic parameters of E. coli growth affected by the two compounds, was obtained and further studied by chemometric techniques including similarity analysis, multivariate analysis of variance, and principal component analysis. By comparing the values of two main parameters, k 2 (growth rate constant of the second exponential phase) and Q 1 (heat output of the first exponential growth phase) of E. coli based on the box and whisker plot, liquiritigenin and liquiritin could be differentiated according to their antibacterial effects; liquiritin with IC50 (half-inhibitory concentration) of 198.6 μg mL(-1) expressed a stronger antibacterial effect than liquiritigenin with IC50 of 337.8 μg mL(-1). The glucoside group in liquiritin containing four additional free hydroxyls in the diphenylpropane skeleton was crucial for inducing the antibacterial effect. Liquiritin might be a promising candidate against E. coli. This study provides a valuable method for searching for novel antibacterial agents using microcalorimetry with chemometrics.

show abstract

Microcalorimetric assays for measuring cell growth and metabolic activity: Methodology and applications

Cited by 69 publications

References 126 publications

An alternative sterility assessment for parenteral drug products using isothermal microcalorimetry

An alternative sterility assessment for parenteral drug products using isothermal microcalorimetry

Growth Patterns of Clostridium difficile – Correlations with Strains, Binary Toxin and Disease Severity: A Prospective Cohort Study

Antibacterial evaluation of flavonoid compounds against E. coli by microcalorimetry and chemometrics

Contact Info

Product

Resources

About