Abstract:
:Metabolic assays are a preferred method for evaluation of Candida albicans viability after exposure to antimicrobial agents in cases in which the culture is a complex mixture of yeast and filamentous forms. There is a lack of published data indicating the strength of the correlation between metabolic assays and viable cell numbers determined by a standard assay such as colony forming units (CFU). We developed a kinetic metabolic assay (KMA) for quantifying viable cells which was tested on yeast cells in both exponential and stationary phase using alamarBlue and XTT as metabolic indicators. The KMA enabled quantification of the viable population over a range of 10(1) to 10(7) cells that linearly correlated (R(2)>0.98) with estimates made by enumeration of CFU regardless of the indicator or growth phase of the cells. Linear relationships were used to calibrate the KMA in terms of equivalent CFU. Viable cell populations were then determined after exposure to AmB. These results were compared with those obtained by direct enumeration of CFU. There were significant correlations between KMA-derived equivalent CFU and direct CFU estimates of viable cell populations for exponential-phase cells. However, the proportions of viable cells based on the KMA were consistently lower than those obtained directly by CFU. This trend was substantially more pronounced for stationary phase cells. These results show that even in the relatively simple case in which only the yeast form is present, the relationship between assessment by metabolic assays and CFU is perturbed by exposure to an antimicrobial and that, furthermore, growth phase alters the nature of the perturbation.
journal_name
J Microbiol Methodsjournal_title
Journal of microbiological methodsauthors
Khot PD,Suci PA,Tyler BJdoi
10.1016/j.mimet.2007.12.005subject
Has Abstractpub_date
2008-03-01 00:00:00pages
268-74issue
3eissn
0167-7012issn
1872-8359pii
S0167-7012(07)00423-Xjournal_volume
72pub_type
杂志文章abstract::The spores and conidia of most fungi have very thick and resistant cell walls that severely impede the staining with fluorescent dyes to allow epifluorescence microscopy to be employed for their direct detection and quantification in natural habitats. In this study, oxidation by sodium hypochlorite and microwave irrad...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2004.07.016
更新日期:2004-12-01 00:00:00
abstract::The purpose of this study was to develop a detection method for viable E. coli O157:H7 in fresh produce and recreational water. The method was evaluated using eight samples of produce wash and recreational water with or without spiked E. coli O157:H7 at ≤10(2) CFU·ml(-1) and concentrated using dead-end ultrafiltration...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2011.09.010
更新日期:2011-12-01 00:00:00
abstract::We have developed an anaerobic biofilm culture system. The system is inexpensive, simple to use and, unlike an anaerobic glovebox, requires no dedicated space. As a test of the system, Porphyromonas gingivalis was cultured under low oxygen (1-2 ppm) and under anaerobic conditions (=0.1 ppm O(2)). In the presence of ...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/s0167-7012(00)00126-3
更新日期:2000-05-01 00:00:00
abstract::Although recent technological advances in DNA sequencing and computational biology now allow scientists to compare entire microbial genomes, comparisons of closely related bacterial species and individual isolates by whole-genome sequencing approaches remains prohibitively expensive for most laboratories. Here we repo...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2005.12.006
更新日期:2006-08-01 00:00:00
abstract::In this study, food-borne yeast isolates (n=96), comprising at least 33 species, were identified using MALDI-TOF MS and conventional methods (API ID 32 C and Phoenix Yeast ID). Discrepancies of both methods were resolved by sequencing the ITS1-5.8S-rRNA-ITS2 region. For ten isolates, mainly classified to Rhodotorula a...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2014.08.021
更新日期:2014-11-01 00:00:00
abstract::Fluorescence in situ hybridization (FISH) can provide information on the morphology, spatial arrangement, and local environment of individual cells enabling the investigation of intact microbial communities. GeneFISH uses polynucleotide probes and enzymatic signal amplification to detect genes that are present in low ...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2021.106147
更新日期:2021-01-22 00:00:00
abstract::Despite advances in antifungal prophylaxis and therapy, morbidity and mortality incurred by yeasts remain a significant burden. As pathogenic yeast species vary in their susceptibilities to antifungal agents, clinical microbiology laboratories face an important challenge to identify them rapidly and accurately. Althou...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2004.09.003
更新日期:2005-01-01 00:00:00
abstract::To date, no single reported DNA extraction method is suitable for the efficient extraction of DNA from all fungal species. The efficiency of extraction is of particular importance in PCR-based medical diagnostic applications where the quantity of fungus in a tissue biopsy may be limited. We subjected 16 medically rele...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2005.06.008
更新日期:2006-04-01 00:00:00
abstract::Aminotransferases (ATs) had previously been detected after native electrophoresis. We show now that aminotransferase(s) of Propionibacterium freudenreichii can be detected after sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Moreover, it retained a high activity (84%) in the presence of 0.23% S...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/s0167-7012(02)00060-x
更新日期:2002-09-01 00:00:00
abstract::Much of our knowledge concerned with microbial cells is based on population-based analysis of cultures, which give useful insights into average responses but neither on individual cells nor subpopulations. In this work we demonstrate how to access and utilise large amounts of valuable information concerned with cell p...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2009.01.011
更新日期:2009-04-01 00:00:00
abstract::Effective biolistic transformation of intact conidia from the filamentous fungus Trichoderma reesei was achieved using the Bio-Rad Hepta Adaptor system with seven barrels for particle launch. Transformation frequencies of up to 39 colonies per microg of circular DNA and 37 colonies per microg of linear DNA were obtain...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/s0167-7012(02)00126-4
更新日期:2002-11-01 00:00:00
abstract::A standard material comprising a few viable cells of a microorganism is essential for rational validation of microbiological methods. We propose a method of a flow cytometric sorting of cells stained with 6-carboxyfluorescein diacetate. The feasibility of tryptic soy medium in this method is demonstrated with 5 strain...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2013.01.021
更新日期:2013-04-01 00:00:00
abstract::One of the known limitations for biosensor assays is the high limit of detection for target cells within complex samples (e.g., Escherichia coli at 10(4) to 10(5) CFU/mL) due to poor capture efficiencies. Currently, researchers can only estimate the cell capture efficiency necessary to produce a positive signal for an...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2007.11.004
更新日期:2008-01-01 00:00:00
abstract::Four different bacterial DNA extraction strategies and two different qPCR probe chemistries were studied for detection of Stapylococcus aureus from white cheeses. Method employing trypsin treatment followed by a commercial kit application and TaqMan probe-based qPCR was the most sensitive one detecting higher counts t...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2014.06.022
更新日期:2014-10-01 00:00:00
abstract::An etiological relationship between periodontitis, a significant oral health problem, and the anaerobe Porphyromonas gingivalis may be related to the expression of a variety of putative virulence factors. The objective of the experiments described here was to develop a quantitative reverse transcription polymerase cha...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/s0167-7012(01)00362-1
更新日期:2002-04-01 00:00:00
abstract::In order to study functional gene expression in Streptomyces coelicolor, a mini-transposon encoding the apramycin resistance gene aac(3)IV within its inverted repeat (IR) boundaries was constructed based on IS204, which was previously identified in the genome of Nocardia asteroides YP21. The mini-transposon and IS204 ...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2011.10.018
更新日期:2012-01-01 00:00:00
abstract::Vibrio cholerae strains producing cholera toxin (CT) and toxin co-regulated pilus (TCP) and belonging to O1 and O139 serogroups are responsible for cholera. However, non-CT producing V. cholerae from non-O1/non-O139 serogroups have been increasingly isolated from diarrheal stools and extra-intestinal infections. In th...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2018.12.012
更新日期:2019-02-01 00:00:00
abstract::Laccase is a key enzyme in the degradation of lignin by fungi. Reports indicate that the activity of this enzyme ranges from 3.5 to 484,000 U L(-1). Our aim was to analyze how laccase activity is calculated in the literature, and to determine statistically whether variations in activity are due to biological propertie...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2015.10.007
更新日期:2015-12-01 00:00:00
abstract::O157, O26, and O111 are the most important O serogroups of enterohemorrhagic Escherichia coli worldwide. Recently we reported a strategy for discriminating these serotypes from the others using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) based on the S10-spc-alpha operon...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2015.11.005
更新日期:2015-12-01 00:00:00
abstract::Characterization of airborne bacterial cells requires efficient collection, concentration, and analysis techniques, particularly to overcome the challenge of their dilute nature in outdoor environments. This study aims to establish a rapid and reliable approach for quantification of bacteria in air samples. To do this...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2018.10.012
更新日期:2018-11-01 00:00:00
abstract::The food industry requires easy, accurate, and cost-effective techniques for microbial identification to ensure safe products and identify microbial contaminations. In this work, FTIR spectroscopy and MALDI-TOF mass spectrometry were assessed for their suitability and applicability for routine microbial diagnostics of...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2014.05.011
更新日期:2014-08-01 00:00:00
abstract::Global public health is threatened by the emergence of potentially dangerous antibiotic drug-resistant strains of Mycobacterium tuberculosis. Point mutations in certain M. tuberculosis genes are associated with the resistance of M. tuberculosis strains to antibiotic drugs. The purpose of this study was to develop a su...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2005.04.026
更新日期:2005-12-01 00:00:00
abstract::The latex agglutination test using single-chain antibody fragments (scFvStx1 and scFvStx2) coupled to latex particles, was compared with the gold standard Vero cell assay for Shiga toxin (Stx) detection, aiming to estimate the diagnosis potential of these scFv fragments in a rapid and straightforward test. The latex c...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2020.105965
更新日期:2020-08-01 00:00:00
abstract::Clostridium difficile is an enteric pathogen that causes approximately 20% to 30% of antibiotic-associated diarrhea. In recent years, there has been a substantial rise in the rate of C. difficile infections as well as the emergence of virulent and antibiotic resistant C. difficile strains. So, there is an urgent need ...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2017.02.008
更新日期:2017-05-01 00:00:00
abstract::A variety of protein expression tags with different biochemical properties has been used to enhance the yield and solubility of recombinant proteins. Ubiquitin, SUMO (small ubiquitin-like modifier) and prokaryotic ubiquitin like MoaD (molybdopterin synthase, small subunit) fusion tags are getting more popular because ...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2015.08.017
更新日期:2015-11-01 00:00:00
abstract::A new, simple approach for the isolation and quantitative analysis of the cell wall (CW) proteins from invasively growing Saccharomyces cerevisiae strains is described in this contribution. The proposed method was proved compatible with agar-invasion assays and was demonstrated to be useful as a screening tool for rap...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2009.09.003
更新日期:2009-12-01 00:00:00
abstract::Neisseria gonorrhoeae (NG) has developed resistance to most antibiotics, making it increasingly difficult to treat. Previous studies have predicted antimicrobial NG susceptibility based on the antimicrobial gene target DNA gyrase subunit A (gyrA) codon serine 91 and the penicillin-binding protein 2 (penA) using Roche ...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2019.105783
更新日期:2020-01-01 00:00:00
abstract::Synthesis and application of reliable nanoscale materials is a progressive domain and the limelight of modern nanotechnology. Conventional physicochemical approaches for the synthesis of metal nanoparticles have become obsolete owing to costly and hazardous materials. There is a need to explore alternative, cost-effec...
journal_title:Journal of microbiological methods
pub_type: 杂志文章,评审
doi:10.1016/j.mimet.2019.02.010
更新日期:2019-04-01 00:00:00
abstract::Staphylococcal Cassette Chromosome mec (SCCmec) element plays a key role in development of resistance by carrying different resistance factors. Therefore, routine and rapid diagnostic approach is considered advantageous for the easy detection of SCCmec elements. So, here we have described the use of three sets of mult...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2019.105733
更新日期:2019-11-01 00:00:00
abstract::A rapid bead assay for detecting pathogenic bacteria with a simple microfluidic chip-based system was developed. Five oligonucleotide probes corresponding to the 16S rRNA of the targeted bacteria were coupled covalently to fluorescent beads. Four species of bacteria (Escherichia coli, Salmonella enterica subsp. enteri...
journal_title:Journal of microbiological methods
pub_type: 杂志文章
doi:10.1016/j.mimet.2006.03.014
更新日期:2006-11-01 00:00:00