Kimon-Andreas Karatzas

Email:
k.karatzas@reading.ac.uk
Phone:
+44 (0) 118 378 6678
Job title:
Associate Professor

Responsibilities:

Co-Director of Postgraduate Research Studies.

Office

3-38

Building location

Harry Nursten

Areas of interest

Molecular mechanisms of acid resistance of bacterial foodborne pathogens and gut microorganisms.
Glutamate and aminoacid decarboxylase systems.
Anaerobic microbiology of bacterial foodborne pathogens, gut microorganisms and anaerobic reactors.
Molecular mechanisms of stress resistance against old and novel food processing techniques (high hydrostatic pressure).
Biocide tolerance of bacterial foodborne pathogens.
Study of the effect of stress mechanisms on the general phenotype (virulence, nutrition, etc,) of bacterial foodborne pathogens.
General stress mechanisms of L. monocytogenes, S. enterica, S. aureus.

Academic qualifications

PhD in Nutrition, Food Technology and Biotechnology, Wageningen Agricultural University, The Netherlands, 2002
Bsc Food Science and Technology, Department of Agriculture, School of Geotechnical Sciences, Aristotle University of Thessaloniki, Greece.

Awards and honours

Starting Investigator Research Grant (SIRG) awarded by Science Foundation Ireland (SFI) – 0.5 million Euros – and Marie Curie – EU funding.

Publications

Kitsiou, M. , Purk, L. , Gutierrez-Merino, J. , Karatzas, K. , Klymenko, O. , Velliou, E. (2023) A systematic quantitative determination of the antimicrobial efficacy of grape seed extract against foodborne bacterial pathogens. Foods , 12 (5). ISSN: 2304-8158 | doi: https://dx.doi.org/10.3390/foods12050929
Monteagudo-Mera, A. , Fanti, V. , Rodriguez-Sobstel, C. , Gibson, G. , Wijeyesekera, A. ORCID: 0000-0001-6151-5065 , Karatzas, K. , Chakrabarti, B. ORCID: 0000-0002-6649-7895 (2023) Gamma aminobutyric acid production by commercially available probiotic strains. Journal of Applied Microbiology , 134 (2). ISSN: 1364-5072 | doi: https://dx.doi.org/10.1093/jambio/lxac066

Kourmentza, K. , Gromada, X. , Michael, N. , Degraeve, C. , Vanier, G. , Ravallec, R. , Coutte, F. , Karatzas, K. , Jauregi, P. (2021) Antimicrobial activity of lipopeptide biosurfactants against foodborne pathogen and food spoilage microorganisms and their cytotoxicity. Frontiers in Microbiology , 11 ISSN: 1664-302X | doi: https://dx.doi.org/10.3389/fmicb.2020.561060
Bulut, S. and Karatzas, K. (2021) Inactivation of Escherichia coli K12 in phosphate buffer saline and orange juice by high hydrostatic pressure processing combined with freezing. LWT-Food Science and Technology , 136 (1). ISSN: 0023-6438 | doi: https://dx.doi.org/10.1016/j.lwt.2020.110313
Karatzas, K. , Lemmens - den Toom, N. , Tassou, C. , van Leeuwen, W. , van Belkum, A. (2021) Molecular characterization of piezotolerant and stress resistant mutants of Staphylococcus aureus. Journal of Applied Microbiology , 130 (3). pp. 901-912. ISSN: 1364-5072 | doi: https://dx.doi.org/10.1111/jam.14832

Kaldis, F. , Cysneiros, D. , Day, J. , Karatzas, K. , Chatzifragkou, A. ORCID: 0000-0002-9255-7871 (2020) Anaerobic digestion of steam-exploded wheat straw and co-digestion strategies for enhanced biogas production. Applied Sciences , 10 (22). ISSN: 2076-3417 | doi: https://dx.doi.org/10.3390/app10228284
Paudyal, R. , O'Byrne, C. , Karatzas, K. (2020) Amino acids other than glutamate affect the expression of the GAD system in Listeria monocytogenes enhancing acid resistance. Food Microbiology , 90 ISSN: 0740-0020 | doi: https://dx.doi.org/10.1016/j.fm.2020.103481
Ekonomou, S. , Bulut, S. , Karatzas, K. , Boziaris, I. (2020) Inactivation of Listeria monocytogenes in raw and hot smoked trout fillets by high hydrostatic pressure processing combined with liquid smoke and freezing. Innovative Food Science & Emerging Technologies , 64 ISSN: 1466-8564 | doi: https://dx.doi.org/10.1016/j.ifset.2020.102427
Abukhabta, S. , Khalil Ghawi, S. , Karatzas, K. , Charalampopoulos, D. ORCID: 0000-0003-1269-8402 , McDougall, G. , Allwood, J. , Verrall, S. , Lavery, S. , Latimer, C. , Pourshahidi, L. , Lawther, R. , O’Connor, G. , Rowland, I. , Gill, C. (2020) Sulforaphane-enriched extracts from glucoraphanin-rich broccoli exert antimicrobial activity against gut pathogens in vitro and innovative cooking methods increase in vivo intestinal delivery of sulforaphane. European Journal of Nutrition ISSN: 1436-6215 | doi: https://dx.doi.org/10.1007/s00394-020-02322-0
Barnes, R. and Karatzas, K. (2020) Investigation into the antimicrobial activity of fumarate against Listeria monocytogenes and its mode of action under acidic conditions. International Journal of Food Microbiology , 324 ISSN: 0168-1605 | doi: https://dx.doi.org/10.1016/j.ijfoodmicro.2020.108614
Julien, L. , Fau, C. , Baron, F. , Bonnassie, S. , Guérin-Dubiard, C. , Nau, F. , Gautier, M. , Karatzas, K. , Jan, S. , Andrews, S. (2020) The three lipocalins of egg-white: only Ex-FABP inhibits siderophore-dependent iron sequestration by Salmonella Enteritidis. Frontiers in Microbiology , 11 ISSN: 1664-302X | doi: https://dx.doi.org/10.3389/fmicb.2020.00913
Boura, M. , Brensone, D. , Karatzas, K. (2020) A novel role for the glutamate decarboxylase system in Listeria monocytogenes; protection against oxidative stress. Food Microbiology , 85 pp 0. ISSN: 0740-0020 | doi: https://dx.doi.org/10.1016/j.fm.2019.103284

Pavli, F. , Gkana, E. , Adebambo, O. , Karatzas, K. , Panagou, E. , Nychas, G. (2019) Ιn Vitro screening of γ-Aminobutyric Acid and Autoinducer-2 signalling in lactic acid bacteria exhibiting probiotic potential isolated from natural black conservolea olives. Foods , 8 (12). pp 0. ISSN: 2304-8158 | doi: https://dx.doi.org/10.3390/foods8120640
Zainal Abidin, M. , Kourmentza, C. , Karatzas, K. , Niranjan, K. (2019) Enzymatic hydrolysis of thermally pre‐treated chitin and antimicrobial activity of N,N'‐diacetylchitobiose. Journal of Chemical Technology and Biotechnology , 94 (8). pp. 2529-2536. ISSN: 1097-4660 | doi: https://dx.doi.org/10.1002/jctb.6043
Kang, S. , Hayashi, Y. , Bruyns-Haylett, M. , Baker, D. , Boura, M. , Wang, H. , Karatzas, K. , Serra, I. , Bithell, A. , Williams, C. , Field, D. , Zheng, Y. (2019) Supplemental vitamin B-12 enhances the neural response to sensory stimulation in the barrel cortex of healthy rats but does not affect spontaneous neural activity. Journal of Nutrition , 149 (5). pp. 730-737. ISSN: 1541-6100 | doi: https://dx.doi.org/10.1093/jn/nxz011
Castelletto, V. , Barnes, R. , Karatzas, K. , Edwards-Gayle, C. , Greco, F. , Hamley, I. ORCID: 0000-0002-4549-0926 , Seitsonen, J. , Ruokolainen, J. (2019) Restructuring of lipid membranes by an arginine-capped peptide bolaamphiphile. Langmuir , 35 (5). pp. 1302-1311. ISSN: 0743-7463 | doi: https://dx.doi.org/10.1021/acs.langmuir.8b01014

Castelletto, V. , Barnes, R. , Karatzas, K. , Edwards-Gayle, C. , Greco, F. , Hamley, I. , Rambo, R. , Seitsonen, J. , Ruokolainen, J. (2018) Arginine-containing surfactant-like peptides: interaction with lipid membranes and antimicrobial activity. Biomacromolecules , 19 (7). pp. 2782-2794. ISSN: 1525-7797 | doi: https://dx.doi.org/10.1021/acs.biomac.8b00391
Srisukchayakul, P. , Charalampopoulos, D. , Karatzas, K. (2018) Study on the effect of citric acid adaptation toward the subsequent survival of Lactobacillus plantarum NCIMB 8826 in low pH fruit juices during refrigerated storage. Food Research International , 111 pp. 198-204. ISSN: 0963-9969 | doi: https://dx.doi.org/10.1016/j.foodres.2018.05.018
Abdullah, W. , Mackey, B. , Karatzas, K. (2018) High phenotypic variability among representative strains of common Salmonella enterica serovars with possible implications for food safety. Journal of Food Protection , 81 (1). pp. 93-104. ISSN: 0362-028X | doi: https://dx.doi.org/10.4315/0362-028x.jfp-17-190
Paudyal, R. , Barnes, R. , Karatzas, K. (2018) A novel approach in acidic disinfection through inhibition of acid resistance mechanisms; Maleic acid-mediated inhibition of glutamate decarboxylase activity enhances acid sensitivity of Listeria monocytogenes. Food Microbiology , 69 pp. 96-104. ISSN: 0740-0020 | doi: https://dx.doi.org/10.1016/j.fm.2017.07.013

Abdullah, W. , Mackey, B. , Karatzas, K. (2017) Biofilm formation of Salmonella enterica and the central role of RpoS sigma factor in stress resistance. Malaysian Applied Biology , 46 (3). pp. 59-65. ISSN: 0126-8643
Abdullah, W. , Mackey, B. , Karatzas, K. (2017) Determination of the relative effects of temperature, pH and water activity in food systems: a meta-analysis study. Malaysian Applied Biology , 46 (3). pp. 67-70. ISSN: 0126-8643
Morales, M. , Ardö, Y. , Berthier, F. , Karatzas, K. , Bintsis, T. (2017) Blue-veined cheeses. Global Cheesemaking Technology: Cheese Quality and Characteristics. Global Cheesemaking Technology pp. 415-435. ISBN: 9781119046158 | doi: https://dx.doi.org/10.1002/9781119046165.ch11
Hartmann, K. , Licitra, G. , Eugster-Meier, E. , Fröhlich-Wyder, M. , Jakob, E. , Wechsler, D. , Maubois, J. , Karatzas, K. , Bintsis, T. , Alichanidis, E. , Morales, M. , Berthier, F. , Uzunsoy, İ. , Özer, B. , Ardö, Y. (2017) Hard cheeses. Global Cheesemaking Technology: Cheese Quality and Characteristics. Global Cheesemaking Technology pp. 204-246. ISBN: 9781119046158 | doi: https://dx.doi.org/10.1002/9781119046165.ch2
Spiteri, D. , Chot-Plassot, C. , Sclear, J. , Karatzas, K. , Scerri, C. , Valdramidis, V. (2017) Ultrasound processing of liquid system(s) and its antimicrobial mechanism of action. Letters in Applied Microbiology , 65 (4). pp. 313-318. ISSN: 0266-8254 | doi: https://dx.doi.org/10.1111/lam.12776
Castelletto, V. , Kaur, A. , Hamley, I. ORCID: 0000-0002-4549-0926 , Barnes, R. , Karatzas, K. , Hermida-Merino, D. , Swioklo, S. , Connon, C. , Stasiak, J. , Reza, M. , Ruokolainen, J. (2017) Hybrid membrane biomaterials from self-assembly in polysaccharide and peptide amphiphile mixtures: controllable structural and mechanical properties and antimicrobial activity. RSC Advances , 7 (14). pp. 8366-8375. ISSN: 2046-2069 | doi: https://dx.doi.org/10.1039/C6RA27244D

Kourkoutas, Y. , Chorianopoulos, N. , Karatzas, K. , Banat, I. (2016) Bioactive natural products 2016. BioMed Research International , 2016 ISSN: 2314-6141 | doi: https://dx.doi.org/10.1155/2016/9749305
Paudyal, R. and Karatzas, K. (2016) Stress adaptation of Listeria monocytogenes in acidic ready-to-eat products. In: Kotzekidou, P. , (eds.) Food Hygiene and Toxicology in Ready-to-Eat Foods. Academic Press , London. pp. 167-182. ISBN: 9780128019160 | doi: https://dx.doi.org/10.1016/B978-0-12-801916-0.00010-8
Boura, M. , Keating, C. , Royet, K. , Paudyal, R. , O’Donoghue, B. , O'Byrne, C. , Karatzas, K. (2016) Loss of SigB in Listeria monocytogenes strains EGD-e and 10403S leads to hypersensitivity to hydrogen peroxide in stationary phase under aerobic conditions. Applied and Environmental Microbiology , 82 (15). pp. 4584-4591. ISSN: 0099-2240 | doi: https://dx.doi.org/10.1128/AEM.00709-16
Kourkoutas, Y. , Chorianopoulos, N. , Nisiotou, A. , Valdramidis, V. , Karatzas, K. (2016) Editorial. BioMed research international , 2016 pp. 1-2. ISSN: 2314-6133 | doi: https://dx.doi.org/10.1155/2016/9160375

Kourkoutas, Y. , Karatzas, K. , Valdramidis, V. , Chorianopoulos, N. (2015) Bioactive natural products: facts, applications, and challenges. BioMed research international , 2015 ISSN: 2314-6133 | doi: https://dx.doi.org/10.1155/2015/684109

F`eehily, C. , Finnerty, A. , Hill, C. , Casey, P. , Gahan, C. , O’Byrne,, C. , Karatzas, K. (2014) Divergent evolution of the activity and regulation of the glutamate decarboxylase systems in Listeria monocytogenes EGD-e and 10403S : roles in virulence and acid tolerance. PLoS ONE , 9 (11). ISSN: 1932-6203 | doi: https://dx.doi.org/10.1371/journal.pone.0112649

Connolly, J. , Valdramidis, V. , Byrne, E. , Karatzas, K. , Cullen, P. , Keener, K. , Mosnier, J. (2013) Characterization and antimicrobial efficacy against E. coli of a helium/air plasma at atmospheric pressure created in a plastic package. Journal of Physics D: Applied Physics , 46 (3). ISSN: 1361-6463 | doi: https://dx.doi.org/10.1088/0022-3727/46/3/035401
argiri, a. , Zoumpopoulou, g. , Karatzas, K. , Tsakalidou, e. , Nychas, G. , Panagou, E. , Tassou, C. (2013) Selection of potential probiotic lactic acid bacteria from fermented olives by in vitro tests. Food Microbiology , 33 (2). pp. 282-291. ISSN: 0740-0020
Feehily, C. , O'Byrne, C. , Karatzas, K. (2013) Functional γ-aminobutyrate shunt in Listeria monocytogenes: role in acid tolerance and succinate biosynthesis. Applied and Environmental Microbiology , 79 (1). pp. 74-80. ISSN: 0099-2240 | doi: https://dx.doi.org/10.1128/AEM.02184-12

Cysneiros, D. , Banks, C. , Heaven, S. , Karatzas, K. (2012) The effect of pH control and ‘hydraulic flush’ on hydrolysis and Volatile Fatty Acids (VFA) production and profile in anaerobic leach bed reactors digesting a high solids content substrate. Bioresource Technology ISSN: 0960-8524
Feehily, C. and Karatzas, K. (2012) Role of glutamate metabolism in bacterial responses towards acid and other stresses. Journal of Applied Microbiology , 114 (1). pp. 11-24. ISSN: 1364-5072 | doi: https://dx.doi.org/10.1111/j.1365-2672.2012.05434
Madeo, M. , O'Riordan, N. , Fuchs, T. , Utratna, M. , Karatzas, K. , O'Byrne, C. (2012) Thiamine plays a critical role in the acid tolerance of Listeria monocytogenes. FEMS Microbiology Letters , 326 (2). pp. 137-143. ISSN: 0378-1097 | doi: https://dx.doi.org/10.1111/j.1574-6968.2011.02442.x
Dadkhah, H. , Bassami, M. , Hashemi, S. , Shahraz, F. , Hosseini, H. , Karatzas, K. , Khaksar, R. (2012) Evaluation and comparison of SYBR Green I Real-Time PCR and TaqMan Real-Time PCR methods for quantitative assay of Listeria monocytogenes in nutrient broth and milk. African Journal of Microbiology Research , 6 (9). pp. 1908-1917. ISSN: 1996-0808 | doi: https://dx.doi.org/10.5897/AJMR11.889
Cysneiros, D. , Banks, C. , Heaven, S. , Karatzas, K. (2012) The role of phase separation and feed cycle length in leach beds coupled to methanogenic reactors for digestion of a solid substrate (Part 1): Optimisation of reactors’ performance. Bioresource Technology , 103 (1). pp. 56-63. ISSN: 0960-8524 | doi: https://dx.doi.org/10.1016/j.biortech.2011.09.094
Karatzas, K. , Suur, L. , O'Byrne, C. (2012) Characterisation of the intracellular-glutamate decarboxylase system (GAD): analysis of its function, transcription and role in the acid resistance of various strains of Listeria monocytogenes. Applied and Environmental Microbiology , 78 (10). pp. 3571-3579. ISSN: 1098-5336 | doi: https://dx.doi.org/10.1128/AEM.00227-12

O'Byrne, C. , Feehily, C. , Ham, R. , Karatzas, K. (2011) A modified rapid enzymatic microtiter plate assay for the quantification of intracellular γ-aminobutyric acid and succinate semialdehyde in bacterial cells. Journal of Microbiological Methods , 84 (1). pp. 137-139. ISSN: 0167-7012 | doi: https://dx.doi.org/10.1016/j.mimet.2010.10.017
Patil, S. , Valdramidis, V. , Karatzas, K. , Cullen, P. , Bourke, P. (2011) Assessing the microbial oxidative stress mechanism of ozone treatment through the responses of Escherichia coli mutants. Journal of Applied Microbiology , 111 (1). pp. 136-144. ISSN: 1364-5072 | doi: https://dx.doi.org/10.1111/j.1365-2672.2011.05021.x
Cysneiros, D. , Banks, C. , Heaven, S. , Karatzas, K. (2011) The role of phase separation and feed cycle length in leach beds coupled to methanogenic reactors for digestion of a solid substrate (Part 2): Hydrolysis, acidification and methanogenesis in a two-phase system. Bioresource Technology , 102 (16). pp. 7393-7400. ISSN: 0960-8524 | doi: https://dx.doi.org/10.1016/j.biortech.2011.05.042

Karatzas, K. , Breannan, O. , Heavin, S. , Morrisey, J. , O'Byrne, C. (2010) Intracellular accumulation of high levels of gamma-aminobutyrate by Listeria monocytogenes 10403S in response to low pH: uncoupling of gamma-aminobutyrate synthesis from efflux in a chemically defined medium. Applied and Environmental Microbiology , 76 (11). pp. 3529-3537. ISSN: 0099-2240 | doi: https://dx.doi.org/10.1128/AEM.03063-09

Karatzas, K. and O’Byrne, C. (2008) The role of sigma B (sB) in the stress adaptations of listeria monocytogenes: overlaps between stress adaptation and virulence. In: Laskin , A. , Gadd , G. , Sariaslani , S. , (eds.) Advances in Applied Microbiology . , 65. Academic Press, Elsevier pp. 116-141. ISBN: 9780123744296
Karatzas, K. , Hocking, P. , Jørgensen, F. , Mattick, K. , Leach, S. , Humphrey, T. (2008) Effects of repeated cycles of acid challenge and growth on the phenotype and virulence of Salmonella enterica. Journal of Applied Microbiology , 105 (5). pp. 1640-1648. ISSN: 1364-5072 | doi: https://dx.doi.org/10.1111/j.1365-2672.2008.03909.x
Abram, F. , Su, W. , Wiedmann, M. , Boor, K. , Coote, P. , Botting, C. , Karatzas, K. , O'Byrne, C. (2008) Proteomic analyses of a Listeria monocytogenes mutant lacking σB identify new components of the σB regulon and highlight a role for σB in the utilization of glycerol. Applied and Environmental Microbiology , 74 (3). pp. 594-604. ISSN: 0099-2240 | doi: https://dx.doi.org/10.1128/AEM.01921-07
Abram, F. , Starr, E. , Karatzas, K. , Wasowska-Matlawska, K. , Boyd, A. , Wiedmann, M. , Boor, K. , Connally, D. , O'Bryne, C. (2008) Identification of components of the Sigma B Regulon in Listeria monocytogenes that contribute to acid and salt tolerance. Applied and Environmental Microbiology , 74 (22). pp. 6848-6858. ISSN: 0099-2240 | doi: https://dx.doi.org/10.1128/AEM.00442-08
Karatzas, K. , Randall, L. , Webber, M. , Piddock, L. , Humphrey, T. , Woodward, M. , Coldham, N. (2008) Phenotypic and proteomic characterization of multiply antibiotic-resistant variants of Salmonella entetica serovar typhimurium selected following exposure to disinfectants. Applied and Environmental Microbiology , 74 (5). pp. 1508-1516. ISSN: 0099-2240 | doi: https://dx.doi.org/10.1128/aem.01931-07
Randall, L. , Bagnall, M. , Karatzas, K. , Coldham, N. , Piddock, L. , Woodward, M. (2008) Fitness and dissemination of disinfectant-selected multiple-antibiotic-resistant (MAR) strains of Salmonella enterica serovar Typhimurium in chickens. Journal of Antimicrobial Chemotherapy , 61 (1). pp. 156-162. ISSN: 0305-7453 | doi: https://dx.doi.org/10.1093/jac/dkm415

Karatzas, K. , Zervos, A. , Tassou, C. , Mallidis, C. , Humphrey, T. (2007) Piezotolerant small-colony variants with increased thermotolerance, antibiotic susceptibility, and low invasiveness in a clonal Staphylococcus aureus population. Applied and Environmental Microbiology , 73 (6). pp. 1873-1881. ISSN: 0099-2240 | doi: https://dx.doi.org/10.1128/AEM.01801-06

Karatzas, K. , Valdramidis, V. , Wells-Bennik, M. (2005) Contingency locus in ctsR of Listeria monocytogenes Scott A: a strategy for occurrence of abundant piezotolerant isolates within clonal populations. Applied and Environmental Microbiology , 71 (12). pp. 8390-8396. ISSN: 0099-2240 | doi: https://dx.doi.org/10.1128/AEM.71.12.8390-8396.2005

Karatzas, K. , Wouters, J. , Gahan, C. , Hill, C. , Tjakko, A. , Bennik, M. (2003) The CtsR regulator of Listeria monocytogenes contains a variant glycine repeat region that affects piezotolerance, stress resistance, motility and virulence. Molecular Microbiology , 49 (5). pp. 1227-1238. ISSN: 0950-382X | doi: https://dx.doi.org/10.1046/j.1365-2958.2003.03636.x

Karatzas, K. and Bennik, M. (2002) Characterization of a Listeria monocytogenes Scott A isolate with high tolerance towards high hydrostatic pressure. Applied and Environmental Microbiology , 68 (7). pp. 3183-3189. ISSN: 0099-2240 | doi: https://dx.doi.org/10.1128/AEM.68.7.3183–3189.2002
Wemekamp-Kamphuis, H. , Karatzas, A. , Wouters, J. , Abee, T. (2002) Enhanced levels of cold shock proteins in Listeria monocytogenes LO28 upon exposure to low temperature and high hydrostatic pressure. Applied and Environmental Microbiology , 68 (2). pp. 456-463. ISSN: 0099-2240 | doi: https://dx.doi.org/10.1128/AEM.68.2.456-463.2002

Karatzas, A. , Kets, E. , Smid, E. , Bennik, M. (2001) The combined action of carvacrol and high hydrostatic pressure on Listeria monocytogenes Scott A. Journal of Applied Microbiology , 90 (3). pp. 463-469. ISSN: 1365-2672 | doi: https://dx.doi.org/10.1046/j.1365-2672.2001.01266.x

Karatzas, K. , Bennik, M. , Smid, E. , Kets, E. (2000) Combined action of S-carvone and mild heat treatment on Listeria monocytogenes Scott A. Journal of Applied Microbiology , 89 (2). pp. 296-301. ISSN: 1364-5072 | doi: https://dx.doi.org/10.1046/j.1365-2672.2000.01110.x

Kimon-Andreas Karatzas

Office

Building location

Areas of interest

Academic qualifications

Awards and honours

Publications

2023

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2008

2007

2005

2003

2002

2001

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