Evaluation of high hydrostatic pressure sensitivity of Staphylococcus aureus and Escherichia coli O157 : H7 by differential scanning calorimetry

Date

2003-11-01

Author

Alpas, Hami
BOZOGLU, F
KALETUNC, G

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

54
views

0
downloads

Differential scanning calorimetry (DSC) was used to evaluate the relative high hydrostatic pressure (HHP) resistances of bacterial strains from Staphylococcus aureus and Escherichia coli O157:H7 in vivo. The total apparent enthalpy change and thermal stability were two DSC parameters used to compare bacterial strains of untreated control and pressure-treated bacteria. DSC thermograms indicated that ribosomal denaturation appears to be a major factor in cell death by both thermal and high pressure treatments. However, the analysis of calorimetric data for control samples as well as pressure-treated samples clearly showed that the sensitivities of bacteria to various physical stresses can be different. While S. aureus 765 had a relatively higher resistance to thermal treatment in comparison to S. aureus 485, S. aureus 485 was determined to be more resistant to pressure than S. aureus 765. This information can be utilized in the design of processes specific to targeting certain cellular components by using different physical stresses.

Subject Keywords

Food Science, Microbiology, General Medicine

URI

https://hdl.handle.net/11511/34709

Journal

INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY

DOI

https://doi.org/10.1016/s0168-1605(03)00066-7

Collections

Department of Food Engineering, Article

Suggestions

OpenMETU
Core

Characterization of extracellular beta-lactamases from penicillin G-resistant cells of Streptococcus thermophilus Chirica, LC; Güray, Nülüfer Tülün; Gültekin, Güzin Candan; Bozoglu, F (International Association for Food Protection, 1998-07-01) In this study, biochemical properties of two extracellular beta-lactamases produced by penicillin-resistant Streptococcus thermophilus cells were investigated. Both beta-lactamases showed specificity for penicillins but not for cephaloridins. The p-lactamases exhibited different affinities for penicillin G. The one with the higher molecular weight (F1) had a K(m) value of 3.44 mu M and a V(max), value of 8.33, mu mol/min/mg of protein, whereas the beta-lactamase with the lower molecular weight (FII) had a K...
Interactions of high hydrostatic pressure, pressurization temperature and pH on death and injury of pressure-resistant and pressure-sensitive strains of foodborne pathogens Alpas, Hami; BOZOGLU, F; RAY, B (Elsevier BV, 2000-09-15) The objective of this: study is to determine the interactions between high hydrostatic pressure, pressurization temperature, time and pH during pressurization on death and injury of pressure-resistant and pressure-sensitive strains of four foodborne pathogens: Staphylococcus aureus 485 and 765, Listeria monocytogenes CA and OH2, Escherichia coli O157:H7 933 and 931, Salmonella enteritidis FDA and Salmonella typhimurium E21274. Among these strains S. aureus 485, L. monocytogenes CA, E, coli O157:H7 933 and S...
Immunization of the industrial fermentation starter culture strain of Saccharomyces cerevisiae to a contaminating killer toxin-producing Candida tropicalis Izgu, F; Altinbay, D; Derinel, Y (Elsevier BV, 2004-12-01) K3 killer trait was introduced into the fermentation starter strain of Saccharomyces cerevisiae BSP 1 in order to construct immune industrial strain that produces K3 type killer toxin and was resistant to Candida tropicalis (K+) contamination. Protoplasts of respiration-deficient Rhodegrees strain of S. cerevisiae NCYC 761 (K3) and S. cerevisiae BSP 1 were fused. The resulting respiration-competent hybrid with K3 type killer activity was selected on media containing a non-fermentable carbon source and by a ...
Analysis of a bac operon-silenced strain suggests pleiotropic effects of bacilysin in Bacillus subtilis Ertekin, Ozan; Taskin, Ash Aras; Demir, Mustafa; Karataş, Ayten; Özcengiz, Gülay (Springer Science and Business Media LLC, 2020-04-01) Bacilysin, as the simplest peptide antibiotic made up of only L-alanine and L-anticapsin, is produced and excreted by Bacillus subtilis under the control of quorum sensing. We analyzed bacilysin-nonproducing strain OGU1 which was obtained by bacA-targeted pMutin T3 insertion into the parental strain genome resulting in a genomic organization (bacA '::lacZ::erm::bacABCDEF) to form an IPTG-inducible bac operon. Although IPTG induction provided 3- to 5-fold increment in the transcription of bac operon genes, n...
Inactivation of Escherichia coli and Listeria innocua in kiwifruit and pineapple juices by high hydrostatic pressure Buzrul, Sencer; Alpas, Hami; Largeteau, Alain; Demazeau, Gerard (Elsevier BV, 2008-06-10) Escherichia coli and Listeria innocua in kiwifruit and pineapple juices were exposed to high hydrostatic Pressure (HHP) at 300 MPa for 5 min. Both bacteria showed equal resistance to HHR Using low (0 degrees C) or subzero (- 10 degrees C) temperatures instead of room temperature (20 degrees C) during pressurization did not change the effectiveness of HHP treatment oil both bacteria in Studied juices. Pulse pressure treatment (multiple Pulses for a total holding time of 5 min at 300 MPa) instead of continuou...

Citation Formats

H. Alpas, F. BOZOGLU, and G. KALETUNC, “Evaluation of high hydrostatic pressure sensitivity of Staphylococcus aureus and Escherichia coli O157 : H7 by differential scanning calorimetry,” INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY, pp. 229–237, 2003, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/34709.