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Hannu Korkeala - One of the best experts on this subject based on the ideXlab platform.
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Role of DEAD-box RNA helicase genes in the growth of Yersinia pseudotuberculosis IP32953 under Cold, pH, osmotic, ethanol and oxidative stresses.
PLOS ONE, 2019Co-Authors: Xiaojie Jiang, Riikka Keto-timonen, Mikael Skurnik, Hannu KorkealaAbstract:Yersinia pseudotuberculosis is an important foodborne pathogen threatening modern food safety due to its ability to survive and grow at low temperatures. DEAD-box RNA helicase CsdA has been shown to play an important role in the low-temperature growth of psychrotrophic Y. pseudotuberculosis. A total of five DEAD-box RNA helicase genes (rhlB, csdA, rhlE, dbpA, srmB) have been identified in Y. pseudotuberculosis IP32953. However, their role in various stress conditions used in food production is unclear. We studied the involvement of the DEAD-box RNA helicase-encoding genes in the Cold tolerance of Y. pseudotuberculosis IP32953 using quantitative real-time reverse transcription (RT-qPCR) and mutational analysis. Quantitative RT-PCR revealed that mRNA transcriptional levels of csdA, rhlE, dbpA and srmB were significantly higher after Cold Shock at 3°C compared to non-Shocked culture at 28°C, suggesting the involvement of these four genes in Cold Shock Response at the transcriptional level. The deletion of csdA ceased growth, while the deletion of dbpA or srmB significantly impaired growth at 3°C, suggesting the requirement of these three genes in Y. pseudotuberculosis at low temperatures. Growth of each DEAD-box RNA helicase mutant was also investigated under pH, osmotic, ethanol and oxidative stress conditions. The five helicase-encoding genes did not play major roles in the growth of Y. pseudotuberculosis IP32953 under pH, osmotic, ethanol or oxidative stress.
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Transcriptomic Analysis of (Group I) Clostridium botulinum ATCC 3502 Cold Shock Response
PloS one, 2014Co-Authors: Elias Dahlsten, Miia Lindström, Panu Somervuo, Marita A Isokallio, Hannu KorkealaAbstract:Profound understanding of the mechanisms foodborne pathogenic bacteria utilize in adaptation to the environmental stress they encounter during food processing and storage is of paramount importance in design of control measures. Chill temperature is a central control measure applied in minimally processed foods; however, data on the mechanisms the foodborne pathogen Clostridium botulinum activates upon Cold stress are scarce. Transcriptomic analysis on the C. botulinum ATCC 3502 strain upon temperature downshift from 37°C to 15°C was performed to identify the Cold-responsive gene set of this organism. Significant up- or down-regulation of 16 and 11 genes, respectively, was observed 1 h after the Cold Shock. At 5 h after the temperature downshift, 199 and 210 genes were up- or down-regulated, respectively. Thus, the relatively small gene set affected initially indicated a targeted acute Response to Cold Shock, whereas extensive metabolic remodeling appeared to take place after prolonged exposure to Cold. Genes related to fatty acid biosynthesis, oxidative stress Response, and iron uptake and storage were induced, in addition to mechanisms previously characterized as Cold-tolerance related in bacteria. Furthermore, several uncharacterized DNA-binding transcriptional regulator-encoding genes were induced, suggesting involvement of novel regulatory mechanisms in the Cold Shock Response of C. botulinum. The role of such regulators, CBO0477 and CBO0558A, in Cold tolerance of C. botulinum ATCC 3502 was demonstrated by deteriorated growth of related mutants at 17°C.
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the clo3403 clo3404 two component system of clostridium botulinum e1 beluga is important for Cold Shock Response and growth at low temperatures
Applied and Environmental Microbiology, 2014Co-Authors: Gerald Mascher, Miia Lindström, Yağmur Derman, David G. Kirk, Eveliina Palonen, Hannu KorkealaAbstract:ABSTRACT In order to survive a temperature downshift, bacteria have to sense the changing environment and adjust their metabolism and structure. Two-component signal transduction systems (TCSs) play a central role in sensing and responding to many different environmental stimuli. Although the nonproteolytic (group II) Clostridium botulinum represents a major hazard in chilled foods, the Cold adaption mechanisms of group II C. botulinum organisms are not known. Here, we show that the CLO3403/CLO3404 TCS of C. botulinum E1 Beluga is involved in the Cold Shock Response and growth at 12°C. Cold Shock induced the expression of the genes encoding the histidine kinase (clo3403) and the Response regulator (clo3404) by more than 100-fold after 5 h relative to their expression in a nonShocked culture at the corresponding time point. The involvement of CLO3403/CLO3404 in growth at low temperature was demonstrated by impaired growth of the insertional clo3403 and clo3404 knockout mutants at 12°C compared to the growth of the wild-type culture. Additionally, the inactivation of clo3403 had a negative effect on motility. The growth efficiency at 12°C of the TCS mutants and the motility of the kinase mutants were restored by introducing a plasmid harboring the operon of the CLO3403/CLO3404 TCS. The results suggest that the CLO3403/CLO3404 TCS is important for the Cold tolerance of C. botulinum E1 Beluga.
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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
Applied and Environmental Microbiology, 2012Co-Authors: Miia Lindström, Elias Dahlsten, Henna Söderholm, Katja Selby, Panu Somervuo, John T. Heap, Nigel P. Minton, Hannu KorkealaAbstract:The role of the two-component system (TCS) CBO0366/CBO0365 in the Cold Shock Response and growth of the mesophilic Clostridium botulinum ATCC 3502 at 15°C was demonstrated by induced expression of the TCS genes upon Cold Shock and impaired growth of the TCS mutants at 15°C.
Masayori Inouye - One of the best experts on this subject based on the ideXlab platform.
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Escherichia coli RNase R has dual activities, helicase and RNase
2016Co-Authors: Naoki Awano, Masayori Inouye, Vaishnavi Rajagopal, Mark Arbing, Smita Patel, John Hunt, Sangita PhadtareAbstract:In Escherichia coli, the Cold Shock Response occurs when there is a temperature downshift from 37°C to 15°C, and this Response is characterized by induction of several Cold Shock proteins, including the DEAD-box helicase CsdA, during the acclimation phase. CsdA is involved in a variety of cellular processes. Our previous studies showed that the helicase activity of CsdA is critical for its function in Cold Shock acclimation of cells and that the only proteins that were able to complement its function were another helicase, RhlE, an RNA chaperone, CspA, and a Cold-inducible exoribonuclease, RNase R. Interestingly, other major 3-to-5 process-ing exoribonucleases of E. coli, such as polynucleotide phosphorylase and RNase II, cannot complement the Cold Shock function of CsdA. Here we carried out a domain analysis of RNase R and showed that this protein has two distinct activities, RNase and helicase, which are independent of each other and are due to different domains. Mutant RNase R proteins that lack the RNase activity but exhibit the helicase activity were able to complement the Cold Shock function of CsdA, suggesting that only the helicase activity of RNase R is essential for complementation of the Cold Shock function of CsdA. We also observed that in vivo deletion of the two Cold Shock domains resulted in a loss of the ability of RNase R to complement the Cold Shock function of CsdA. W
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Cold-Shock Response and Adaptation to Near-Freezing Temperature in Cold-Adapted Yeasts
2014Co-Authors: Masayori Inouye, Sangita PhadtareAbstract:Yeasts, such as Saccharomyces cerevisiae, are exposed in their natural habitat to ambient temperatures. They can form colonies at 4 °C and can grow at 10–18 °C. Therefore, the temperature downshift to 10 °C is a moderate Cold stress for yeasts. Thus, there is no dramatic induction of Cold-Shock proteins (CSPs) upon temperature downshift from 30 to 10 °C. On the other hand, the Response observed at near-freezing temperatures is more likely to represent the strong Cold-Shock Response for yeasts. The changes in yeast plasma membrane fluidity are the primary signal triggering the Cold-Shock Response. The Responses of the yeast cell to temperature downshift to 10 °C can be categorized into three phases. The early and mid-phases are characterized by the initial up-regulation of a number of genes that are associated with the transcriptional machinery, which is then followed by an up-regulation of the translational machinery in the mid-phase. The third phase is characterized by the transcriptional activation of typical stress-marker genes, for example, the heat-Shock protein (HSP) genes, and genes that are involved in the cellular processes of metabolism and signal transduction. On the other hand, it has been shown that the Cold-induced accumulation of trehalose, glycerol, and HSPs plays a crucial role in protecting the yeast cells against freeze injury. Each of these three cryoprotectants is discussed in detail, along with the relevance of these studies for biotechnological application of yeasts.
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The Cold Shock Response.
EcoSal Plus, 2008Co-Authors: Sangita Phadtare, Masayori InouyeAbstract:This review focuses on the Cold Shock Response of Escherichia coli. Change in temperature is one of the most common stresses that an organism encounters in nature. Temperature downshift affects the cell on various levels: (i) decrease in the membrane fluidity; (ii) stabilization of the secondary structures of RNA and DNA; (iii) slow or inefficient protein folding; (iv) reduced ribosome function, affecting translation of non-Cold Shock proteins; (v) increased negative supercoiling of DNA; and (vi) accumulation of various sugars. Cold Shock proteins and certain sugars play a key role in dealing with the initial detrimental effect of Cold Shock and maintaining the continued growth of the organism at low temperature. CspA is the major Cold Shock protein of E. coli, and its homologues are found to be widespread among bacteria, including psychrophilic, psychrotrophic, mesophilic, and thermophilic bacteria, but are not found in archaea or cyanobacteria. Significant, albeit transient, stabilization of the cspA mRNA immediately following temperature downshift is mainly responsible for its Cold Shock induction. Various approaches were used in studies to detect Cold Shock induction of cspA mRNA. Sugars are shown to confer protection to cells undergoing Cold Shock. The study of the Cold Shock Response has implications in basic and health-related research as well as in commercial applications. The Cold Shock Response is elicited by all types of bacteria and affects these bacteria at various levels, such as cell membrane, transcription, translation, and metabolism.
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rnase activity of polynucleotide phosphorylase is critical at low temperature in escherichia coli and is complemented by rnase ii
Journal of Bacteriology, 2008Co-Authors: Naoki Awano, Masayori Inouye, Sangita PhadtareAbstract:In Escherichia coli, the Cold Shock Response is exerted upon a temperature change from 37°C to 15°C and is characterized by induction of several Cold Shock proteins, including polynucleotide phosphorylase (PNPase), during acclimation phase. In E. coli, PNPase is essential for growth at low temperatures; however, its exact role in this essential function has not been fully elucidated. PNPase is a 3′-to-5′ exoribonuclease and promotes the processive degradation of RNA. Our screening of an E. coli genomic library for an in vivo counterpart of PNPase that can compensate for its absence at low temperature revealed only one protein, another 3′-to-5′ exonuclease, RNase II. Here we show that the RNase PH domains 1 and 2 of PNPase are important for its Cold Shock function, suggesting that the RNase activity of PNPase is critical for its essential function at low temperature. We also show that its polymerization activity is dispensable in its Cold Shock function. Interestingly, the third 3′-to-5′ processing exoribonuclease, RNase R of E. coli, which is Cold inducible, cannot complement the Cold Shock function of PNPase. We further show that this difference is due to the different targets of these enzymes and stabilization of some of the PNPase-sensitive mRNAs, like fis, in the Δpnp cells has consequences, such as accumulation of ribosomal subunits in the Δpnp cells, which may play a role in the Cold sensitivity of this strain.
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Genome-Wide Transcriptional Analysis of the Cold Shock Response in Wild-Type and Cold-Sensitive, Quadruple-csp-Deletion Strains of Escherichia coli
Journal of bacteriology, 2004Co-Authors: Sangita Phadtare, Masayori InouyeAbstract:A DNA microarray-based global transcript profiling of Escherichia coli in Response to Cold Shock showed that in addition to the known Cold Shock-inducible genes, new genes such as the flagellar operon, those encoding proteins involved in sugar transport and metabolism, and remarkably, genes encoding certain heat Shock proteins are induced by Cold Shock. In the light of strong reduction in metabolic activity of the cell after temperature downshift, the induction of sugar metabolism machinery is unexpected. The deletion of four csps (cspA, cspB, cspG, and cspE) affected Cold Shock induction of mostly those genes that are transiently induced in the acclimation phase, emphasizing that CspA homologues are essential in the acclimation phase. Relevance of these findings with respect to the known RNA chaperone function of CspA homologues is discussed.
Sangita Phadtare - One of the best experts on this subject based on the ideXlab platform.
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Escherichia coli RNase R has dual activities, helicase and RNase
2016Co-Authors: Naoki Awano, Masayori Inouye, Vaishnavi Rajagopal, Mark Arbing, Smita Patel, John Hunt, Sangita PhadtareAbstract:In Escherichia coli, the Cold Shock Response occurs when there is a temperature downshift from 37°C to 15°C, and this Response is characterized by induction of several Cold Shock proteins, including the DEAD-box helicase CsdA, during the acclimation phase. CsdA is involved in a variety of cellular processes. Our previous studies showed that the helicase activity of CsdA is critical for its function in Cold Shock acclimation of cells and that the only proteins that were able to complement its function were another helicase, RhlE, an RNA chaperone, CspA, and a Cold-inducible exoribonuclease, RNase R. Interestingly, other major 3-to-5 process-ing exoribonucleases of E. coli, such as polynucleotide phosphorylase and RNase II, cannot complement the Cold Shock function of CsdA. Here we carried out a domain analysis of RNase R and showed that this protein has two distinct activities, RNase and helicase, which are independent of each other and are due to different domains. Mutant RNase R proteins that lack the RNase activity but exhibit the helicase activity were able to complement the Cold Shock function of CsdA, suggesting that only the helicase activity of RNase R is essential for complementation of the Cold Shock function of CsdA. We also observed that in vivo deletion of the two Cold Shock domains resulted in a loss of the ability of RNase R to complement the Cold Shock function of CsdA. W
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Cold-Shock Response and Adaptation to Near-Freezing Temperature in Cold-Adapted Yeasts
2014Co-Authors: Masayori Inouye, Sangita PhadtareAbstract:Yeasts, such as Saccharomyces cerevisiae, are exposed in their natural habitat to ambient temperatures. They can form colonies at 4 °C and can grow at 10–18 °C. Therefore, the temperature downshift to 10 °C is a moderate Cold stress for yeasts. Thus, there is no dramatic induction of Cold-Shock proteins (CSPs) upon temperature downshift from 30 to 10 °C. On the other hand, the Response observed at near-freezing temperatures is more likely to represent the strong Cold-Shock Response for yeasts. The changes in yeast plasma membrane fluidity are the primary signal triggering the Cold-Shock Response. The Responses of the yeast cell to temperature downshift to 10 °C can be categorized into three phases. The early and mid-phases are characterized by the initial up-regulation of a number of genes that are associated with the transcriptional machinery, which is then followed by an up-regulation of the translational machinery in the mid-phase. The third phase is characterized by the transcriptional activation of typical stress-marker genes, for example, the heat-Shock protein (HSP) genes, and genes that are involved in the cellular processes of metabolism and signal transduction. On the other hand, it has been shown that the Cold-induced accumulation of trehalose, glycerol, and HSPs plays a crucial role in protecting the yeast cells against freeze injury. Each of these three cryoprotectants is discussed in detail, along with the relevance of these studies for biotechnological application of yeasts.
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escherichia coli Cold Shock gene profiles in Response to over expression deletion of csda rnase r and pnpase and relevance to low temperature rna metabolism
Genes to Cells, 2012Co-Authors: Sangita PhadtareAbstract:Cold Shock Response is elicited by the transfer of exponentially growing cells from their optimum temperature to a significantly lower growth temperature and is characterized by the induction of several Cold Shock proteins. These proteins, which presumably possess a variety of different activities, are critical for survival and continued growth at low temperature. One of the main consequences of Cold Shock is stabilization of the secondary structures in nucleic acids leading to hindrance of RNA degradation. Cold-Shock proteins such as RNA helicase CsdA, and 3’-5’ processing exoribonucleases such as PNPase and RNase R, are presumably involved in facilitating the RNA metabolism at low temperature. As a step towards elucidating the individual contributions of these proteins to low-temperature RNA metabolism, the global transcript profiles of cells lacking CsdA, RNase R, and PNPase proteins as well as cells individually overexpressing these proteins as compared to the wild-type cells were analyzed at 15°C. The analysis revealed distinct sets of genes, which are possible targets of each of these proteins. This analysis will help further our understanding of the low temperature RNA metabolism.
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The Cold Shock Response.
EcoSal Plus, 2008Co-Authors: Sangita Phadtare, Masayori InouyeAbstract:This review focuses on the Cold Shock Response of Escherichia coli. Change in temperature is one of the most common stresses that an organism encounters in nature. Temperature downshift affects the cell on various levels: (i) decrease in the membrane fluidity; (ii) stabilization of the secondary structures of RNA and DNA; (iii) slow or inefficient protein folding; (iv) reduced ribosome function, affecting translation of non-Cold Shock proteins; (v) increased negative supercoiling of DNA; and (vi) accumulation of various sugars. Cold Shock proteins and certain sugars play a key role in dealing with the initial detrimental effect of Cold Shock and maintaining the continued growth of the organism at low temperature. CspA is the major Cold Shock protein of E. coli, and its homologues are found to be widespread among bacteria, including psychrophilic, psychrotrophic, mesophilic, and thermophilic bacteria, but are not found in archaea or cyanobacteria. Significant, albeit transient, stabilization of the cspA mRNA immediately following temperature downshift is mainly responsible for its Cold Shock induction. Various approaches were used in studies to detect Cold Shock induction of cspA mRNA. Sugars are shown to confer protection to cells undergoing Cold Shock. The study of the Cold Shock Response has implications in basic and health-related research as well as in commercial applications. The Cold Shock Response is elicited by all types of bacteria and affects these bacteria at various levels, such as cell membrane, transcription, translation, and metabolism.
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rnase activity of polynucleotide phosphorylase is critical at low temperature in escherichia coli and is complemented by rnase ii
Journal of Bacteriology, 2008Co-Authors: Naoki Awano, Masayori Inouye, Sangita PhadtareAbstract:In Escherichia coli, the Cold Shock Response is exerted upon a temperature change from 37°C to 15°C and is characterized by induction of several Cold Shock proteins, including polynucleotide phosphorylase (PNPase), during acclimation phase. In E. coli, PNPase is essential for growth at low temperatures; however, its exact role in this essential function has not been fully elucidated. PNPase is a 3′-to-5′ exoribonuclease and promotes the processive degradation of RNA. Our screening of an E. coli genomic library for an in vivo counterpart of PNPase that can compensate for its absence at low temperature revealed only one protein, another 3′-to-5′ exonuclease, RNase II. Here we show that the RNase PH domains 1 and 2 of PNPase are important for its Cold Shock function, suggesting that the RNase activity of PNPase is critical for its essential function at low temperature. We also show that its polymerization activity is dispensable in its Cold Shock function. Interestingly, the third 3′-to-5′ processing exoribonuclease, RNase R of E. coli, which is Cold inducible, cannot complement the Cold Shock function of PNPase. We further show that this difference is due to the different targets of these enzymes and stabilization of some of the PNPase-sensitive mRNAs, like fis, in the Δpnp cells has consequences, such as accumulation of ribosomal subunits in the Δpnp cells, which may play a role in the Cold sensitivity of this strain.
Petri Auvinen - One of the best experts on this subject based on the ideXlab platform.
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transcriptomic time series analysis of Cold and heat Shock Response in psychrotrophic lactic acid bacteria
BMC Genomics, 2021Co-Authors: Ilhan Cem Duru, Anne Ylinen, Sergei Belanov, Alan Avila Pulido, Lars Paulin, Petri AuvinenAbstract:Background Psychrotrophic lactic acid bacteria (LAB) species are the dominant species in the microbiota of Cold-stored modified-atmosphere-packaged food products and are the main cause of food spoilage. Despite the importance of psychrotrophic LAB, their Response to Cold or heat has not been studied. Here, we studied the transcriptome-level Cold- and heat-Shock Response of spoilage lactic acid bacteria with time-series RNA-seq for Le. gelidum, Lc. piscium, and P. oligofermentans at 0 °C, 4 °C, 14 °C, 25 °C, and 28 °C. Results We observed that the Cold-Shock protein A (cspA) gene was the main Cold-Shock protein gene in all three species. Our results indicated that DEAD-box RNA helicase genes (cshA, cshB) also play a critical role in Cold-Shock Response in psychrotrophic LAB. In addition, several RNase genes were involved in Cold-Shock Response in Lc. piscium and P. oligofermentans. Moreover, gene network inference analysis provided candidate genes involved in Cold-Shock Response. Ribosomal proteins, tRNA modification, rRNA modification, and ABC and efflux MFS transporter genes clustered with Cold-Shock Response genes in all three species, indicating that these genes could be part of the Cold-Shock Response machinery. Heat-Shock treatment caused upregulation of Clp protease and chaperone genes in all three species. We identified transcription binding site motifs for heat-Shock Response genes in Le. gelidum and Lc. piscium. Finally, we showed that food spoilage-related genes were upregulated at Cold temperatures. Conclusions The results of this study provide new insights on the Cold- and heat-Shock Response of psychrotrophic LAB. In addition, candidate genes involved in Cold- and heat-Shock Response predicted using gene network inference analysis could be used as targets for future studies.
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transcriptomic time series analysis of Cold and heat Shock Response in psychrotrophic lactic acid bacteria
BMC Genomics, 2021Co-Authors: Ilhan Cem Duru, Anne Ylinen, Sergei Belanov, Alan Avila Pulido, Lars Paulin, Petri AuvinenAbstract:Psychrotrophic lactic acid bacteria (LAB) species are the dominant species in the microbiota of Cold-stored modified-atmosphere-packaged food products and are the main cause of food spoilage. Despite the importance of psychrotrophic LAB, their Response to Cold or heat has not been studied. Here, we studied the transcriptome-level Cold- and heat-Shock Response of spoilage lactic acid bacteria with time-series RNA-seq for Le. gelidum, Lc. piscium, and P. oligofermentans at 0 °C, 4 °C, 14 °C, 25 °C, and 28 °C. We observed that the Cold-Shock protein A (cspA) gene was the main Cold-Shock protein gene in all three species. Our results indicated that DEAD-box RNA helicase genes (cshA, cshB) also play a critical role in Cold-Shock Response in psychrotrophic LAB. In addition, several RNase genes were involved in Cold-Shock Response in Lc. piscium and P. oligofermentans. Moreover, gene network inference analysis provided candidate genes involved in Cold-Shock Response. Ribosomal proteins, tRNA modification, rRNA modification, and ABC and efflux MFS transporter genes clustered with Cold-Shock Response genes in all three species, indicating that these genes could be part of the Cold-Shock Response machinery. Heat-Shock treatment caused upregulation of Clp protease and chaperone genes in all three species. We identified transcription binding site motifs for heat-Shock Response genes in Le. gelidum and Lc. piscium. Finally, we showed that food spoilage-related genes were upregulated at Cold temperatures. The results of this study provide new insights on the Cold- and heat-Shock Response of psychrotrophic LAB. In addition, candidate genes involved in Cold- and heat-Shock Response predicted using gene network inference analysis could be used as targets for future studies.
Miia Lindström - One of the best experts on this subject based on the ideXlab platform.
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Transcriptomic Analysis of (Group I) Clostridium botulinum ATCC 3502 Cold Shock Response
PloS one, 2014Co-Authors: Elias Dahlsten, Miia Lindström, Panu Somervuo, Marita A Isokallio, Hannu KorkealaAbstract:Profound understanding of the mechanisms foodborne pathogenic bacteria utilize in adaptation to the environmental stress they encounter during food processing and storage is of paramount importance in design of control measures. Chill temperature is a central control measure applied in minimally processed foods; however, data on the mechanisms the foodborne pathogen Clostridium botulinum activates upon Cold stress are scarce. Transcriptomic analysis on the C. botulinum ATCC 3502 strain upon temperature downshift from 37°C to 15°C was performed to identify the Cold-responsive gene set of this organism. Significant up- or down-regulation of 16 and 11 genes, respectively, was observed 1 h after the Cold Shock. At 5 h after the temperature downshift, 199 and 210 genes were up- or down-regulated, respectively. Thus, the relatively small gene set affected initially indicated a targeted acute Response to Cold Shock, whereas extensive metabolic remodeling appeared to take place after prolonged exposure to Cold. Genes related to fatty acid biosynthesis, oxidative stress Response, and iron uptake and storage were induced, in addition to mechanisms previously characterized as Cold-tolerance related in bacteria. Furthermore, several uncharacterized DNA-binding transcriptional regulator-encoding genes were induced, suggesting involvement of novel regulatory mechanisms in the Cold Shock Response of C. botulinum. The role of such regulators, CBO0477 and CBO0558A, in Cold tolerance of C. botulinum ATCC 3502 was demonstrated by deteriorated growth of related mutants at 17°C.
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the clo3403 clo3404 two component system of clostridium botulinum e1 beluga is important for Cold Shock Response and growth at low temperatures
Applied and Environmental Microbiology, 2014Co-Authors: Gerald Mascher, Miia Lindström, Yağmur Derman, David G. Kirk, Eveliina Palonen, Hannu KorkealaAbstract:ABSTRACT In order to survive a temperature downshift, bacteria have to sense the changing environment and adjust their metabolism and structure. Two-component signal transduction systems (TCSs) play a central role in sensing and responding to many different environmental stimuli. Although the nonproteolytic (group II) Clostridium botulinum represents a major hazard in chilled foods, the Cold adaption mechanisms of group II C. botulinum organisms are not known. Here, we show that the CLO3403/CLO3404 TCS of C. botulinum E1 Beluga is involved in the Cold Shock Response and growth at 12°C. Cold Shock induced the expression of the genes encoding the histidine kinase (clo3403) and the Response regulator (clo3404) by more than 100-fold after 5 h relative to their expression in a nonShocked culture at the corresponding time point. The involvement of CLO3403/CLO3404 in growth at low temperature was demonstrated by impaired growth of the insertional clo3403 and clo3404 knockout mutants at 12°C compared to the growth of the wild-type culture. Additionally, the inactivation of clo3403 had a negative effect on motility. The growth efficiency at 12°C of the TCS mutants and the motility of the kinase mutants were restored by introducing a plasmid harboring the operon of the CLO3403/CLO3404 TCS. The results suggest that the CLO3403/CLO3404 TCS is important for the Cold tolerance of C. botulinum E1 Beluga.
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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
Applied and Environmental Microbiology, 2012Co-Authors: Miia Lindström, Elias Dahlsten, Henna Söderholm, Katja Selby, Panu Somervuo, John T. Heap, Nigel P. Minton, Hannu KorkealaAbstract:The role of the two-component system (TCS) CBO0366/CBO0365 in the Cold Shock Response and growth of the mesophilic Clostridium botulinum ATCC 3502 at 15°C was demonstrated by induced expression of the TCS genes upon Cold Shock and impaired growth of the TCS mutants at 15°C.