Motility-activating mutations upstream of flhDC reduce acid shock survival of Escherichia coli
Ontology highlight
ABSTRACT:
ORGANISM(S): Escherichia coli BW25113 Escherichia coli str. K-12 substr. MG1655
PROVIDER: GSE260455 | GEO | 2024/04/14
REPOSITORIES: GEO
Similar Datasets
Project description:Substrains in Escherichia coli K-12 MG1655 can possess various swimming motility, which is mostly resulted from different expression levels of flhDC. Here, we studied the swimming motility of two MG1655 substrains, CY562 and CY570. Our results showed that CY562 had no insertion at the promoter region of flhDC and possessed no swimming motility. In contrast, CY570 had an IS-element insertion at the promoter region of flhDC and showed a hyper-motile phenotype. Transcriptomic data suggest that expression of flhDC and the other known flagella genes was much lower in CY562 than that in CY570. Moreover, CY562 possessed higher expression levels for genes involved in stress response, especially acid-stress response, than CY570. Consistently, CY562 showed a higher survival rate under acid stress than CY570. Our data indicate that there are mechanisms conversely regulating motility and stress response in E. coli.
2021-11-15 | GSE165438 | GEO
Project description:Bacterial motility shows a strong evolvable feature depending on the environment. Hyper-motile E. coli could be isolated by evolving non-motile E. coli due to the mutations that enhanced transcriptional expression of the master regulator of the flagellum biosynthesis, FlhDC. These hyper-motile isolates showed reduced growth fitness but with the molecular mechanisms unrevealed. Here we obtained a novel type of hyper-motile isolates by evolving a weakly-motile E. coli K12 strain on the soft agar plates. These isolates carried high accumulated FlhDC proteins and they shared one single point mutation of ClpXV78F. The V78F affected the ATP binding to ClpX via steric repulsive effect and the mutated ClpXP protease lost most of its ability to degraded FlhDC and some other of its known targets. The signal tag of FlhDC for ClpXP recognition was also characterized. Intriguingly, in the hyper-motile strains, the highly enhanced expression of the motility genes was accompanied by the reduced expression of stress resistance genes relating to the reduced fitness of these isolates. Hence, ClpX appeared to be a novel and hot locus during the evolution of bacterial motility and the molecular mechanism of the trade-off between motility and growth was proposed for the first time.
2021-11-15 | GSE165151 | GEO
Project description:Bacterial motility shows a strong evolvable feature depending on the environment. Hyper-motile E. coli could be isolated by evolving non-motile E. coli due to the mutations that enhanced transcriptional expression of the master regulator of the flagellum biosynthesis, FlhDC. These hyper-motile isolates showed reduced growth fitness but with the molecular mechanisms unrevealed. Here we obtained a novel type of hyper-motile isolates by evolving a weakly-motile E. coli K12 strain on the soft agar plates. These isolates carried high accumulated FlhDC proteins and they shared one single point mutation of ClpXV78F. The V78F affected the ATP binding to ClpX via steric repulsive effect and the mutated ClpXP protease lost most of its ability to degraded FlhDC and some other of its known targets. The signal tag of FlhDC for ClpXP recognition was also characterized. Intriguingly, in the hyper-motile strains, the highly enhanced expression of the motility genes was accompanied by the reduced expression of stress resistance genes relating to the reduced fitness of these isolates. Hence, ClpX appeared to be a novel and hot locus during the evolution of bacterial motility and the molecular mechanism of the trade-off between motility and growth was proposed for the first time.
2021-11-25 | PXD023645 | Pride
Project description:Expression and use of motility genes is a potentially beneficial but costly process in bacteria. Interestingly, many isolate strains of Escherichia coli possess motility genes but have lost the ability to activate them in conditions in which motile cells are advantageous, raising the question of how they respond to these situations. Through transcriptome profiling of strains in the E. coli single-gene knockout Keio collection, we noticed drastic upregulation of motility genes in many of the deletion strains as compared to its typically non-motile parent strain (BW25113). This switch to a motile phenotype is not a direct consequence of the genes deleted, but is instead due to a variety of secondary mutations that increase the synthesis of the major motility regulator, FlhDC. We found that a phenotypic switch to motility at a population level can be induced in non-motile E. coli strains by incubation in non-shaking liquid medium overnight but not in shaking media. Individual isolates after the overnight incubation acquired distinct mutations upstream of the flhDC operon, including different insertion sequence (IS) elements and, to a lesser extent, point mutations. The rapid sweep in the non-shaking population shows that non-motile strains without existing regulatory mechanisms can quickly adapt to a motile lifestyle by quickly acquired genetic changes.
2019-07-11 | GSE129161 | GEO
Project description:The heat shock response is critical for organisms to survive at a high temperature. Heterologous expression of eukaryotic molecular chaperons protects Escherichia coli against heat stress. Here we report that expression of the plant E3 ligase BnTR1 significantly increase the thermotolerance of Escherichia coli. Different from eukaryotic chaperones, BnTR1 post-transcriptionally regulates the heat shock factor σ32 though zinc fingers of the RING domain, which interacts with DnaK resulting in stabilizing σ32 and subsequently up-regulating heat shock proteins. Our findings indicate the expression of BnTR1 confers thermoprotective effects on E. coli cells, and it may provide useful clues to engineer thermophilic bacterial strains.
2016-08-19 | GSE85807 | GEO
Project description:Although protein acetylation is widely observed, it has been associated with few specific regulatory functions making it poorly understood. To interrogate its functionality, we analyzed the acetylome in Escherichia coli knockout mutants of cobB, the only known sirtuin-like deacetylase, and patZ, the best-known protein acetyltransferase. For four growth conditions, more than 2,000 unique acetylated peptides, belonging to 809 proteins, were identified and differentially quantified. Nearly 65% of these proteins are related to metabolism. The global activity of CobB contributes to the deacetylation of a large number of substrates and has a major impact on physiology. Apart from the regulation of acetyl-CoA synthetase, we found that CobB-controlled acetylation of isocitrate lyase contributes to the fine-tuning of the glyoxylate shunt. Acetylation of the transcription factor RcsB prevents DNA binding, activating flagella biosynthesis and motility, and increases acid stress susceptibility. Surprisingly, deletion of patZ increased acetylation in acetate cultures, which suggests that it regulates the levels of acetylating agents. The results presented offer new insights into functional roles of protein acetylation in metabolic fitness and global cell regulation. In this study we aimed to discover how the deregulation of protein acetylation could alter physiology in E. coli. We observed that the deletion of both cobB or patZ genes in E. coli altered gene expression, specially those genes related with motility, chemotaxis and acid stress response. We used three biological replicates in this study and each condition. The control in these experiments was E. coli BW25113
2014-10-07 | E-GEOD-62094 | biostudies-arrayexpress
Project description:E. coli frequently encounters oxidative stress both in its natural environment or in industrial biotechnology. Elucidating the mechanisms behind tolerance to oxidative stress would be beneficial for understanding pathogenesis as well as improving production strain fitness. We make use of adaptive laboratory evolution to develop two strains of E. coli which exhibit 500% increased tolerance to paraquat stress compared to wild type. Evolved strains tolerate oxidative stress by reduction of flux through TCA, dyregulation of iron-uptake genes, and up-regulation of cell motility or iron-sulfur cluster repair genes.
2022-07-07 | GSE134256 | GEO
Project description:Bacteria growing as surface-adherent biofilms are better able to withstand chemical and physical stresses than their unattached, planktonic counterparts. Using transcriptional profiling and quantitative PCR, we observed a previously uncharacterized gene, yjfO, to be upregulated during Escherichia coli MG1655 biofilm growth in a chemostat on serine-limited defined medium. A yjfO mutant, developed through targeted insertion mutagenesis, and a yjfO-complemented strain, were obtained for further characterization. While bacterial surface colonization levels (CFU/cm2) were similar in all three strains, the mutant strain exhibited reduced microcolony formation when observed in flow cells, and greatly enhanced flagellar motility on soft (0.3%) agar. Complementation of yjfO restored microcolony formation and flagellar motility to wild type levels. Cell surface hydrophobicity and twitching motility were unaffected by the presence or absence of yjfO. In contrast to the parent strain, biofilms from the mutant strain were less able to resist acid and peroxide stresses. yjfO had no significant effect on E. coli biofilm susceptibility to alkali or heat stress. Planktonic cultures from all three strains showed similar responses to these stresses. Regardless of the presence of yjfO, planktonic E. coli withstood alkali stress better than biofilm populations. Complementation of yjfO restored viability following exposure to peroxide stress, but did not restore acid resistance. Based on its influence on biofilm formation, stress response, and effects on motility, we propose renaming the uncharacterized gene, yjfO, as bsmA (biofilm stress and motility). Transcriptional profiling of duplicate biofilm and planktonic cultures of E. coli MG1655 grown in serine-limited MOPS minimal media.
2010-06-21 | E-GEOD-18362 | biostudies-arrayexpress
Project description:Although protein acetylation is widely observed, it has been associated with few specific regulatory functions making it poorly understood. To interrogate its functionality, we analyzed the acetylome in Escherichia coli knockout mutants of cobB, the only known sirtuin-like deacetylase, and patZ, the best-known protein acetyltransferase. For four growth conditions, more than 2,000 unique acetylated peptides, belonging to 809 proteins, were identified and differentially quantified. Nearly 65% of these proteins are related to metabolism. The global activity of CobB contributes to the deacetylation of a large number of substrates and has a major impact on physiology. Apart from the regulation of acetyl-CoA synthetase, we found that CobB-controlled acetylation of isocitrate lyase contributes to the fine-tuning of the glyoxylate shunt. Acetylation of the transcription factor RcsB prevents DNA binding, activating flagella biosynthesis and motility, and increases acid stress susceptibility. Surprisingly, deletion of patZ increased acetylation in acetate cultures, which suggests that it regulates the levels of acetylating agents. The results presented offer new insights into functional roles of protein acetylation in metabolic fitness and global cell regulation. In this study we aimed to discover how the deregulation of protein acetylation could alter physiology in E. coli. We observed that the deletion of both cobB or patZ genes in E. coli altered gene expression, specially those genes related with motility, chemotaxis and acid stress response.
2014-10-07 | GSE62094 | GEO
Project description:Bacteria growing as surface-adherent biofilms are better able to withstand chemical and physical stresses than their unattached, planktonic counterparts. Using transcriptional profiling and quantitative PCR, we observed a previously uncharacterized gene, yjfO, to be upregulated during Escherichia coli MG1655 biofilm growth in a chemostat on serine-limited defined medium. A yjfO mutant, developed through targeted insertion mutagenesis, and a yjfO-complemented strain, were obtained for further characterization. While bacterial surface colonization levels (CFU/cm2) were similar in all three strains, the mutant strain exhibited reduced microcolony formation when observed in flow cells, and greatly enhanced flagellar motility on soft (0.3%) agar. Complementation of yjfO restored microcolony formation and flagellar motility to wild type levels. Cell surface hydrophobicity and twitching motility were unaffected by the presence or absence of yjfO. In contrast to the parent strain, biofilms from the mutant strain were less able to resist acid and peroxide stresses. yjfO had no significant effect on E. coli biofilm susceptibility to alkali or heat stress. Planktonic cultures from all three strains showed similar responses to these stresses. Regardless of the presence of yjfO, planktonic E. coli withstood alkali stress better than biofilm populations. Complementation of yjfO restored viability following exposure to peroxide stress, but did not restore acid resistance. Based on its influence on biofilm formation, stress response, and effects on motility, we propose renaming the uncharacterized gene, yjfO, as bsmA (biofilm stress and motility).
2009-10-17 | GSE18362 | GEO