Research Information System
Fresenius Environmental Bulletin, vol.29, no.12, pp.11677-11684, 2020 (SCI-Expanded)
Yersiniosis infection is frequently seen in
aquatic products and causes great economic losses.
Infection occurs at water temperatures of 15-22 oC.
In this study, the Yersinia ruckeri strain was
developed in the TSA medium and at 1.0 OD density
at 600 nm. Then, 100ul of the same concentration of
suspension was added to the 25 ml TSA and 25 ml
SW medium and incubated for 24 hours at different
temperatures (15, 20, 25, 37). Gram staining,
catalase, oxidase, and motility tests of developing
bacteria were investigated. The API 20E kit was
used according to the manufacturer's instructions to
determine phenotypic characterization and
temperature-related differences. The molecular
identification of the agent at different temperatures
at the same density was carried out in Real-Time
PCR with the primer assay specific for the 16S
rRNA gene. Western blot analysis was performed to
determine the differences in expression at the protein
level at different temperatures.
The results of the study revealed that TSA and
SW media developed in the media and Gramnegative
and catalase oxidase were positive. The
motility was lost at 37 oC. In the results of
phenotypic characterization performed with API
20E, incubation at different temperatures revealed
differences in CIT, VP, and GEL tests on the same
bacteria. Y. ruckeri strains of the same optical
density in the follow-up of the DNA isolation of 16S
rRNA gene region-specific primer assays performed
Real-Time PCR analysis of all of the bacterial DNA
used in the same optic density (OD) because of the
very close to the Ct values were found to be positive
and give sigmoidal curves give positive results. The
results were also confirmed after the analysis
whether the samples reacted with the use of
standards and automatic threshold values. After the
formation of PCR amplicons, melting curve analysis
revealed peaks formed by melting curves and it was
understood that there was no false positivity. Total
protein levels obtained by the Bradford method were
determined as 0.1384 at 15 oC, 0.1777 at 20 oC,
0.1820 at 25 oC, and 0.1857 at 37 oC. It was found
that there was no change in the gene expression
profile of the same bacterium developed in TSA and
SW media. Given the results of the protein
expression obtained from the page ruler prestained
protein ladder, significant changes in the level of
gene expression are observed under different
temperature conditions of the strain. One of the most
striking ones is the gene product seen in the 20 and
25 oC groups at the level of 110 kDa. While this gene
product is not expressed at low and high
temperatures, the optimum level of expression is
significantly increased. Increased gene products due
to temperature increase are seen at approximately 90
kDa, 65 kDa, and 30 kDa. When the temperaturedependent
expression levels decreased, it was found
to be around 40 kDa and 45 kDa.