Prior exposure to microbial-associated molecular patterns or specific chemical compounds can promote plants into a primed state with stronger defence responses.β-aminobutyric acid(BABA)is an endogenous stress metabol...Prior exposure to microbial-associated molecular patterns or specific chemical compounds can promote plants into a primed state with stronger defence responses.β-aminobutyric acid(BABA)is an endogenous stress metabolite that induces resistance protecting various plants towards diverse stresses.In this study,by integrating BABA-induced changes in selected metabolites with transcriptome and proteome data,we generated a global map of the molecular processes operating in BABA-induced resistance(BABA-IR)in tomato.BABA significantly restricts the growth of the pathogens Oidium neolycopersici and Phytophthora parasitica but not Botrytis cinerea.A cluster analysis of the upregulated processes showed that BABA acts mainly as a stress factor in tomato.The main factor distinguishing BABA-IR from other stress conditions was the extensive induction of signaling and perception machinery playing a key role in effective resistance against pathogens.Interestingly,the signalling processes and immune response activated during BABA-IR in tomato differed from those in Arabidopsis with substantial enrichment of genes associated with jasmonic acid(JA)and ethylene(ET)signalling and no change in Asp levels.Our results revealed key differences between the effect of BABA on tomato and other model plants studied until now.Surprisingly,salicylic acid(SA)is not involved in BABA downstream signalization whereas ET and JA play a crucial role.展开更多
The diverse clinical presentation of Helicobacter pylori (H. pylori) infection results from the interaction between bacterial virulence, host genetics, socio-demographic and environmental factors. This study aimed to ...The diverse clinical presentation of Helicobacter pylori (H. pylori) infection results from the interaction between bacterial virulence, host genetics, socio-demographic and environmental factors. This study aimed to characterize Helicobacter pylori virulence genes and the associated behavioral factors among dyspeptic patients in Burkina Faso. Two hundred and fifty (250) stool samples were collected from patients with dyspepsia seen at health centers in Ouagadougou, Burkina Faso. Bacterial deoxyribonucleic acid (DNA) was extracted using a commercial kit. Virulence genes were detected using conventional multiplex Polymerase Chain Reaction with specific primers. The overall prevalence of Helicobacter pylori of the 250 participants was 91.20%. CagA virulence gene was present among 20.19% of individuals, while babA2 and vacA were detected respectively among 9.65% and 67.54% of the population positive for Helicobacter pylori. Among vacA subtypes, vacAs1 was the most frequent, with 39.04%, followed by vacAi1 (19.74%), vacAi2 (17.54%), and vacAs2 with 10.96%. Regarding vacAm1 and vacAm2, they were less frequent at 6.14% each. “Handwashing three times or less per day” significantly increased the risk of having vacAi2 allele and H. pylori rRNA16s, with p-values of 0.013 and 0.020, respectively. The consumption of non-tap water increases the risk of carrying the cagA virulence gene. Additionally, H. pylori-positive patients living with more than four (4) people in their household had about two times the risk of having the vacAs1 allele. The present study shows the detection of Helicobacter pylori cagA, vacA subtypes, and babA2 by stool a PCR method in Burkina Faso. The strong association between sanitary habits and virulence factors depicts the composite interaction between ecological factors, gastric mucosa, and bacteria. Therefore, the synergic action of these factors should be considered when aiming for bacterial eradication and gastric pathology cure.展开更多
Interactions between BabA and Lewis b (Leb) related antigens are the best characterized adhesin-receptor interactions in Helicobacter pylori (H pylori). Several mechanisms for the regulation of BabA expression are pre...Interactions between BabA and Lewis b (Leb) related antigens are the best characterized adhesin-receptor interactions in Helicobacter pylori (H pylori). Several mechanisms for the regulation of BabA expression are predicted, including at both transcriptional and translational levels. The formation of chimeric proteins (babA /B or babB /A chimeras) seems to play an especially important role in translational regulation. Chimeric BabB/A protein had the potential to bind Leb; however, protein production was subject to phase variation through slipped strand mispairing. The babA gene was cloned initially from strain CCUG17875, which contains a silent babA1 gene and an expressed babA2 gene. The sequence of these two genes differs only by the presence of a 10 bp deletion in the signal peptide sequence of babA1 that eliminates its translational initiation codon. However, the babA1 type deletion was found only in strain CCUG17875. A few studies evaluated BabA status by immunoblot and confirmed that BabA-positive status in Western strains was closely associated with severe clinical outcomes. BabA-positive status also was associated with the presence of other virulence factors (e.g. cagA-positive status and vacA s1 genotype). A small class of strains produced low levels of the BabA protein and lacked Leb binding activity. These were more likely to be associated with increased mucosal inflammation and severe clinical outcomes than BabA-positive strains that exhibited Leb binding activity. The underlying mechanism is unclear, and further studies will be necessary to investigate how the complex BabA-receptor network is functionally coordinated during the interaction of H pylori with the gastric mucosa.展开更多
基金This project was supported by the National Infrastructure France Genomique(Commissariat aux Grands Investissements,ANR-10-INBS-09-03,ANR-10-INBS-09-02).
文摘Prior exposure to microbial-associated molecular patterns or specific chemical compounds can promote plants into a primed state with stronger defence responses.β-aminobutyric acid(BABA)is an endogenous stress metabolite that induces resistance protecting various plants towards diverse stresses.In this study,by integrating BABA-induced changes in selected metabolites with transcriptome and proteome data,we generated a global map of the molecular processes operating in BABA-induced resistance(BABA-IR)in tomato.BABA significantly restricts the growth of the pathogens Oidium neolycopersici and Phytophthora parasitica but not Botrytis cinerea.A cluster analysis of the upregulated processes showed that BABA acts mainly as a stress factor in tomato.The main factor distinguishing BABA-IR from other stress conditions was the extensive induction of signaling and perception machinery playing a key role in effective resistance against pathogens.Interestingly,the signalling processes and immune response activated during BABA-IR in tomato differed from those in Arabidopsis with substantial enrichment of genes associated with jasmonic acid(JA)and ethylene(ET)signalling and no change in Asp levels.Our results revealed key differences between the effect of BABA on tomato and other model plants studied until now.Surprisingly,salicylic acid(SA)is not involved in BABA downstream signalization whereas ET and JA play a crucial role.
文摘The diverse clinical presentation of Helicobacter pylori (H. pylori) infection results from the interaction between bacterial virulence, host genetics, socio-demographic and environmental factors. This study aimed to characterize Helicobacter pylori virulence genes and the associated behavioral factors among dyspeptic patients in Burkina Faso. Two hundred and fifty (250) stool samples were collected from patients with dyspepsia seen at health centers in Ouagadougou, Burkina Faso. Bacterial deoxyribonucleic acid (DNA) was extracted using a commercial kit. Virulence genes were detected using conventional multiplex Polymerase Chain Reaction with specific primers. The overall prevalence of Helicobacter pylori of the 250 participants was 91.20%. CagA virulence gene was present among 20.19% of individuals, while babA2 and vacA were detected respectively among 9.65% and 67.54% of the population positive for Helicobacter pylori. Among vacA subtypes, vacAs1 was the most frequent, with 39.04%, followed by vacAi1 (19.74%), vacAi2 (17.54%), and vacAs2 with 10.96%. Regarding vacAm1 and vacAm2, they were less frequent at 6.14% each. “Handwashing three times or less per day” significantly increased the risk of having vacAi2 allele and H. pylori rRNA16s, with p-values of 0.013 and 0.020, respectively. The consumption of non-tap water increases the risk of carrying the cagA virulence gene. Additionally, H. pylori-positive patients living with more than four (4) people in their household had about two times the risk of having the vacAs1 allele. The present study shows the detection of Helicobacter pylori cagA, vacA subtypes, and babA2 by stool a PCR method in Burkina Faso. The strong association between sanitary habits and virulence factors depicts the composite interaction between ecological factors, gastric mucosa, and bacteria. Therefore, the synergic action of these factors should be considered when aiming for bacterial eradication and gastric pathology cure.
基金(in part) National Institutes of Health Grants, R01 DK62813
文摘Interactions between BabA and Lewis b (Leb) related antigens are the best characterized adhesin-receptor interactions in Helicobacter pylori (H pylori). Several mechanisms for the regulation of BabA expression are predicted, including at both transcriptional and translational levels. The formation of chimeric proteins (babA /B or babB /A chimeras) seems to play an especially important role in translational regulation. Chimeric BabB/A protein had the potential to bind Leb; however, protein production was subject to phase variation through slipped strand mispairing. The babA gene was cloned initially from strain CCUG17875, which contains a silent babA1 gene and an expressed babA2 gene. The sequence of these two genes differs only by the presence of a 10 bp deletion in the signal peptide sequence of babA1 that eliminates its translational initiation codon. However, the babA1 type deletion was found only in strain CCUG17875. A few studies evaluated BabA status by immunoblot and confirmed that BabA-positive status in Western strains was closely associated with severe clinical outcomes. BabA-positive status also was associated with the presence of other virulence factors (e.g. cagA-positive status and vacA s1 genotype). A small class of strains produced low levels of the BabA protein and lacked Leb binding activity. These were more likely to be associated with increased mucosal inflammation and severe clinical outcomes than BabA-positive strains that exhibited Leb binding activity. The underlying mechanism is unclear, and further studies will be necessary to investigate how the complex BabA-receptor network is functionally coordinated during the interaction of H pylori with the gastric mucosa.
