Project description:The purple bacterium Rhodopseudomonas palustris is a model organism for dissecting the energy and electron transfer processes that have evolved in phototrophic organisms. This bacterium is of particular interest because, in addition to driving its metabolism via solar energy capture, it is capable of nitrogen and carbon dioxide fixation, producing hydrogen and utilising a wide range of organic compounds. Understanding these processes underpins the potential exploitation of Rhodopseudomonas palustris for synthetic biology, biohydrogen production and bioremediation, for example. Like other purple bacteria, Rhodopseudomonas palustris has 2 light-harvesting (LH) systems: LH1 and LH2. The former has already been extensively characterised by X-ray crystallography and cryo-EM. The aim of this proteomics project is to provide complementary information to support the cryo-EM mapping of LH2 structure.
Project description:Indole is an intercellular and interkingdom signaling molecule, which is widespread in diverse ecological niches. Caenorhabditis elegans is a bacterivorous nematode living in soil and compost environments and a useful model host for the study of host-microbe interactions. While various bacteria and some plants produce a large quantity of extracellular indole, little is known about the effects of indole, its derivatives, and indole-producing bacteria on behaviors in C. elegans and animals. Here, we show that C. elegans senses and moves toward indole and indole-producing bacteria, such as Escherichia coli, Shigella boydii, Providencia stuartii, and Klebsiella oxytoca, while avoids non-indole producing pathogenic bacteria. It was also found that indole-producing bacteria and non-indole-producing bacteria exert divergent effects on egg-laying behavior of C. elegans via indole. In addition, various indole derivatives also modulate chemotaxis, egg-laying behavior, and survival of C. elegans. In contrast, indole at a high concentration to kill C. elegans that has the ability to detoxify indole via oxidation and glucosylation, indicating predator-prey interactions via a double-edged molecule indole. Transcriptional analysis showed that indole markedly up-regulated gene expression of cytochrome P450 family, UDP-glucuronosyltransferase, glutathione S-transferase, which explained well the modification of indole in C. elegans, while down-regulated expression of collagen genes and F-box genes. Our findings suggest that indole and its derivatives are important interkingdom signaling molecules in bacteria-nematode interactions.
Project description:We have previously reported that phosphoenolpyruvate carboxykinase(Pck) overexpression under glycolytic conditions enables Escherichia coli to harbor a high intracellular ATP pool resulting in enhanced recombinant protein synthesis and biohydrogen production. To understand possible reasons of the high ATP haboring cell, we carried out transcriptome and metabolic flux analysis.
Project description:Neonatal hypoxic-ischemic encephalopathy (HIE) refers to nervous system damage caused by perinatal hypoxia, which is the major cause of long-term neuro-developmental disorders in surviving infants. However, the mechanisms still require further investigation. In this study, we found that the butanoate metabolism pathway exhibited significantly decreased and short chain fatty acid (SCFAs)-producing bacteria, especially butyrate-producing bacteria, were significantly decreased in fecal of neonatal hypoxic-ischemic brain damage (HIBD) rats. Surprisingly, Sodium butyrate (SB) treatment could ameliorate pathological damage both in the cerebral cortex and hippocampus and facilitate recovery of SCFAs-producing bacteria related to metabolic pathways in neonatal HIBD rats. Moreover, we found that in samples from SB treatment neonatal HIBD rats cortex with high levels of butyrate acid along with aberrant key crotonyl-CoA-producing enzymes ACADS levels was observed compared HIBD rats. We also demonstrated that a decrease in histone 3-lysine 9-crotonylation (H3K9cr) downregulated expression of the HIE-related neurotrophic genes Bdnf, Gdnf, Cdnf, and Manf in HIBD rats. Furthermore, SB restored H3K9cr binding to HIE-related neurotrophic genes. Collectively, our results indicate that SB contributes to ameliorate pathological of HIBD by altering gut microbiota and brain SCFAs levels subsequently affecting histone crotonylation-mediated neurotrophic-related genes expression. This may be a novel microbiological approach for preventing and treating HIE.
Project description:Interventions: Colibactin positive patients are given biolactis (3 g/day) for 3 months.
Primary outcome(s): Detection of colibactin-producing bacteria 90 days after the start of the intervention.
Study Design: single arm study, open(masking not used), no treatment control/standard of care control, single assignment, basic science
