TY - JOUR
T1 - Profiling acylated homoserine lactones in Yersinia ruckeri and influence of exogenous acyl homoserine lactones and known quorum-sensing inhibitors on protease production
AU - Kastbjerg, Vicky Gaedt
AU - Nielsen, Kristian Fog
AU - Dalsgaard, Inger
AU - Rasch, Maria
AU - Bruhn, Jesper Bartholin
AU - Givskov, Michael Christian
AU - Gram, Lone
PY - 2007
Y1 - 2007
N2 - To profile the quorum-sensing (QS) signals in Yersinia ruckeri and to examine the possible regulatory link between QS signals and a typical QS-regulated virulence phenotype, a protease. Methods and Results: Liquid chromatography-high resolution mass spectrometry (HPLC-HRMS) showed that Y. ruckeri produced at least eight different acylated homoserine lactones (AHLs) with N-(3-oxooctanoyl)-l-homoserine lactone (3-oxo-C8-HSL) being the dominant molecule. Also, some uncommon AHL, N-(3-oxoheptanoyl)-l-homoserine lactone (3-oxo-C7-HSL) and N-(3-oxononanoyl)-l-homoserine lactone (3-oxo-C9-HSL), were produced. 3-oxo-C8-HSL was detected in organs from fish infected with Y. ruckeri. Protease production was significantly lower at temperatures above 23 degrees C than below although growth was faster at the higher temperatures. Neither addition of sterile filtered high-density Y. ruckeri culture supernatant nor the addition of pure exogenous AHLs induced protease production. Furthermore, three QS inhibitors (QSIs), sulfur-containing AHL analogues, did not inhibit protease production in Y. ruckeri. Conclusions: Exogenous AHL or sulfur-containing AHL analogues did not influence the protease production indicating that protease production may not be QS regulated in Y. ruckeri. Significance and Impact of the Study: The array of different AHLs produced indicates that the QS system of Y. ruckeri is complex and could involve several regulatory systems. In this case, neither AHLs nor QSI would be likely to directly affect a QS-regulated phenotype.
AB - To profile the quorum-sensing (QS) signals in Yersinia ruckeri and to examine the possible regulatory link between QS signals and a typical QS-regulated virulence phenotype, a protease. Methods and Results: Liquid chromatography-high resolution mass spectrometry (HPLC-HRMS) showed that Y. ruckeri produced at least eight different acylated homoserine lactones (AHLs) with N-(3-oxooctanoyl)-l-homoserine lactone (3-oxo-C8-HSL) being the dominant molecule. Also, some uncommon AHL, N-(3-oxoheptanoyl)-l-homoserine lactone (3-oxo-C7-HSL) and N-(3-oxononanoyl)-l-homoserine lactone (3-oxo-C9-HSL), were produced. 3-oxo-C8-HSL was detected in organs from fish infected with Y. ruckeri. Protease production was significantly lower at temperatures above 23 degrees C than below although growth was faster at the higher temperatures. Neither addition of sterile filtered high-density Y. ruckeri culture supernatant nor the addition of pure exogenous AHLs induced protease production. Furthermore, three QS inhibitors (QSIs), sulfur-containing AHL analogues, did not inhibit protease production in Y. ruckeri. Conclusions: Exogenous AHL or sulfur-containing AHL analogues did not influence the protease production indicating that protease production may not be QS regulated in Y. ruckeri. Significance and Impact of the Study: The array of different AHLs produced indicates that the QS system of Y. ruckeri is complex and could involve several regulatory systems. In this case, neither AHLs nor QSI would be likely to directly affect a QS-regulated phenotype.
U2 - 10.1111/j.1365-2672.03190x
DO - 10.1111/j.1365-2672.03190x
M3 - Journal article
VL - 102
SP - 363
EP - 374
JO - Letters in Applied Microbiology
JF - Letters in Applied Microbiology
SN - 0266-8254
IS - 2
ER -