XXII. BIOCHEMICKÝ ZJAZD - Jesseniova lekárska fakulta

Posters
23.
STUDY OF THERMOTOLEraNCE ISLAND IN CronoBACTer SPP
Jana Gajdošová 1 , Natália Kamodyová 1 , Kristína Benedikovičová 1 , Hana Drahovská 1 ,
Eva Kaclíková 2 and Ján Turňa 1
1
Department of Molecular Biology, Faculty of Natural Sciences, Comenius University,
Mlynská dolina 1, 842 15 Bratislava, Slovensko
2
Food Research Institute, Priemyselná 4, Bratislava
Cronobacter spp. is an opportunistic pathogen associated with sporadic cases of infections
in infants. Dried infant milk formula has been identified as a potential source of the
microorganism and the mode of transmission. The spread of Cronobacter in dried foods
is promoted by its higher resistance than other Enterobacteriaceae to environmental
stresses, including heating, drying or osmotic stress.
The aim of our work was to characterize DNA region, which is present in some Cronobacter
strains and which contributes to their elevated survival at 58°C. The thermotolerance
island was sequenced in C. sakazakii LMG 5740, the length of the region was 19 kbp
and 22 orfs with the size 141 – 2850 bp were detected. The greatest part of the region
contained a cluster of conservative genes, most of them have significant homologies with
bacterial proteins involved in some type of stress response, including heat, oxidation
and acid stress. Similar organization of the region was observed in all thermotolerant
strains. By rt-PCR approach we detected high expression throughout all thermotolerance
gene cluster in both stationary and exponentially grown bacteria. Part of the thermotolerance
genomic island covering orfD-G was cloned to pUC21 under lac promoter and
transformed to E. coli host strain. Recombinant strain showed 80% increased D 58
value
comparing with control strain containing the vector only.
140 XXII. Biochemistry Congress, Martin