Journal: Applied and Environmental Microbiology
Article Title: Involvement of Two-Component System CBO0366/CBO0365 in the Cold Shock Response and Growth of Group I (Proteolytic) Clostridium botulinum ATCC 3502 at Low Temperatures
doi: 10.1128/AEM.00555-12
Figure Lengend Snippet: Relative expression levels of cbo0365 and cbo0366 in ATCC 3502 induced at 15°C. (A) ATCC 3502 was grown at 37°C, exposed to a temperature downshift (cold shock [gray curve]) at 15°C at an optical density at 600 nm (OD600) of 1.5, and sampled for qRT-PCR analysis before cold shock (T0) and 1 min, 30 min, 2 h, and 5 h after cold shock. A non-cold-shocked culture (black curve) served as a control. (B) Relative expression levels of cbo0365 (light gray) and cbo0366 (dark gray) in non-cold-shocked cultures calibrated at T0. (C) Relative expression levels of cbo0365 (light gray) and cbo0366 (dark gray) in cold-shocked cultures calibrated at T0. (D) Relative expression levels of cbo0365 (light gray) and cbo0366 (dark gray) in cold-shocked cultures calibrated to non-cold-shocked cultures at the corresponding time points. The normalization reference was 16S rrn. *, P < 0.05 (one-way analysis of variance). Error bars indicate standard deviations of three replicates.
Article Snippet: While constitutive expression and delicately balanced control through a phosphorelay system have been reported for most TCSs under normal growth conditions ( 18 , 19 , 24 , 30 ), induced TCS expression under cold stress conditions has been reported for B. subtilis and the psychrotrophic Y. pseudotuberculosis ( 4 , 31 ). table ft1 table-wrap mode="anchored" t5 caption a7 Strain or plasmid Relevant properties Source a (reference) Bacterial strains C. botulinum ATCC 3502 Wild type ATCC ( 34 ) C. botulinum ATCC 3502 cbo0365 ::intron- erm Insertion deletion in cbo0365 This study C. botulinum ATCC 3502 cbo0366 ::intron- erm Insertion deletion in cbo0366 This study E. coli TOP10 Electrocompetence Invitrogen, Paisley, UK E. coli CA434 Conjugation donor UNOTT ( 33 ) Plasmids pMTL82153 pBP1 g-positive replicon, catP , ColE1 g-negative replicon, tra , fdx promoter UNOTT ( 22 ) pMTL82153- cbo0366 pMTL82153 with cbo0366 under transcriptional control of fdx promoter This study pMTL007 ClosTron plasmid, catP , intron with ermB RAM UNOTT ( 21 ) pMTL007- cbo0365- 48s Derived from pMTL007 by retargeting to cbo0365 This study pMTL007- cbo0366- 267s Derived from pMTL007 by retargeting to cbo0366 This study Open in a separate window a ATCC, American Type Culture Collection; UNOTT, University of Nottingham, United Kingdom.
Techniques: Expressing, Quantitative RT-PCR, Control