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EBioMedicine Apr 2024Chemoresistance is a critical factor contributing to poor prognosis in clinical patients with cancer undergoing postoperative adjuvant chemotherapy. The role of gut...
BACKGROUND
Chemoresistance is a critical factor contributing to poor prognosis in clinical patients with cancer undergoing postoperative adjuvant chemotherapy. The role of gut microbiota in mediating resistance to tumour chemotherapy remains to be investigated.
METHODS
Patients with CRC were categorised into clinical benefit responders (CBR) and no clinical benefit responders (NCB) based on chemotherapy efficacy. Differential bacterial analysis using 16S rRNA sequencing revealed Desulfovibrio as a distinct microbe between the two groups. Employing a syngeneic transplantation model, we assessed the effect of Desulfovibrio on chemotherapy by measuring tumour burden, weight, and Ki-67 expression. We further explored the mechanisms underlying the compromised chemotherapeutic efficacy of Desulfovibrio using metabolomics, western blotting, colony formation, and cell apoptosis assays.
FINDINGS
In comparison, Desulfovibrio was more abundant in the NCB group. In vivo experiments revealed that Desulfovibrio colonisation in the gut weakened the efficacy of FOLFOX. Treatment with Desulfovibrio desulfuricans elevates serum S-adenosylmethionine (SAM) levels. Interestingly, SAM reduced the sensitivity of CRC cells to FOLFOX, thereby promoting the growth of CRC tumours. These experiments suggest that SAM promotes the growth and metastasis of CRC by driving the expression of methyltransferase-like 3 (METTL3).
INTERPRETATION
A high abundance of Desulfovibrio in the intestines indicates poor therapeutic outcomes for postoperative neoadjuvant FOLFOX chemotherapy in CRC. Desulfovibrio drives the manifestation of METTL3 in CRC, promoting resistance to FOLFOX chemotherapy by increasing the concentration of SAM.
FUNDING
This study is supported by Wuxi City Social Development Science and Technology Demonstration Project (N20201005).
Topics: Humans; Apoptosis; Colorectal Neoplasms; Desulfovibrio desulfuricans; Fluorouracil; Methyltransferases; RNA, Ribosomal, 16S; Leucovorin; Organoplatinum Compounds; Antineoplastic Combined Chemotherapy Protocols
PubMed: 38484555
DOI: 10.1016/j.ebiom.2024.105041 -
Biophysical Reviews Oct 2023The processes of microbiological destruction of toxic and large-tonnage waste are the most attractive processes for protecting the environment. The review considers the... (Review)
Review
The processes of microbiological destruction of toxic and large-tonnage waste are the most attractive processes for protecting the environment. The review considers the results of studies of microbial decomposition of nitrate esters, including hardly decomposable nitrocellulose. The published data show that specific microorganisms are able to degrade nitrated cellulose compounds under both anaerobic and aerobic conditions. The most promising microorganisms in terms of the efficiency of the nitrocellulose degradation process are bacteria belonging to genera, fungi and , as well as their co-cultivation. Recently, the first information about the enzymes involved in the process of nitrocellulose degradation, possible mechanisms of reactions carried out by these enzymes, and the effect of electron donors and acceptors adding to the process have been obtained. Contamination of industrial wastewater with nitrocellulose leads to treatment necessity by using cost-effective, harmless methods. A combined aerobic-anaerobic system, including both bacteria and fungi, has shown hopeful results.
PubMed: 37974989
DOI: 10.1007/s12551-023-01159-1 -
Environmental Research Nov 2023Uranium pollution in groundwater environment has become an important issue of global concern. In this study, a strain of Desulfovibrio desulfuricans was isolated from...
Uranium pollution in groundwater environment has become an important issue of global concern. In this study, a strain of Desulfovibrio desulfuricans was isolated from the tailings of acid heap leaching, and was shown to be able to remove uranium from water via biosorption, bio-reduction, passive biomineralization under uranium stress, and active metabolically dependent bioaccumulation. This research explored the effects of nutrients, pH, initial uranium and sulfate concentration on the functional groups, uranium valence, and crystal size and morphology of uranium immobilization products. Results showed that tetravalent and hexavalent phosphorus-containing uranium minerals was both formed. In sulfate-containing water where Desulfovibrio desulfuricans A3-21ZLL can grow, the sequestration of uranium by bio-reduction was significantly enhanced compared to that with no sulfate loading or no growth. Ungrown Desulfovibrio desulfuricans A3-21ZLL or dead ones released inorganic phosphate group in response to the stress of uranium, which associated with soluble uranyl ion to form insoluble uranium-containing precipitates. This study revealed the influence of hydrochemical conditions on the mineralogy characteristics and spatial distribution of microbial uranium immobilization products. This study is conducive to the long-term and stable bioremediation of groundwater in decommissioned uranium mining area.
PubMed: 37660876
DOI: 10.1016/j.envres.2023.116950 -
Emerging Infectious Diseases Aug 2023An 84-year-old man in Japan who had undergone endovascular aortic repair 9 years earlier had an infected aneurysm develop. We detected Desulfovibrio desulfuricans MB at...
An 84-year-old man in Japan who had undergone endovascular aortic repair 9 years earlier had an infected aneurysm develop. We detected Desulfovibrio desulfuricans MB at the site. The patient recovered after surgical debridement, artificial vessel replacement, and appropriate antimicrobial therapy. Clinicians should suspect Desulfovibrio spp. infection in similar cases.
Topics: Male; Humans; Aged, 80 and over; Desulfovibrio desulfuricans; Aneurysm; Japan
PubMed: 37486321
DOI: 10.3201/eid2908.230403 -
Gut Microbes 2024Diet is a key player in gut-liver axis. However, the effect of different dietary patterns on gut microbiota and liver functions remains unclear. Here, we used rodent...
Diet is a key player in gut-liver axis. However, the effect of different dietary patterns on gut microbiota and liver functions remains unclear. Here, we used rodent standard chow and purified diet to mimic two common human dietary patterns: grain and plant-based diet and refined-food-based diet, respectively and explored their impacts on gut microbiota and liver. Gut microbiota experienced a great shift with notable increase in , gut bile acid (BA) levels elevated significantly, and liver inflammation was observed in mice fed with the purified diet. Liver inflammation and elevated gut BA levels also occurred in mice fed with the chow diet after receiving ATCC 29,577 (DSV). Restriction of sulfur-containing amino acids (SAAs) prevented liver injury mainly through higher hepatic antioxidant and detoxifying ability and reversed the elevated BA levels due to excess . fermentation of human fecal microbiota with primary BAs demonstrated that DSV enhanced production of secondary BAs. Higher concentration of both primary and secondary BAs were found in the gut of germ-free mice after receiving DSV. In conclusion, Restriction of SAAs in diet may become an effective dietary intervention to prevent liver injury associated with excess in the gut.
Topics: Animals; Gastrointestinal Microbiome; Mice; Liver; Humans; Desulfovibrio; Male; Mice, Inbred C57BL; Bile Acids and Salts; Amino Acids; Diet; Feces; Sulfur; Amino Acids, Sulfur
PubMed: 38935546
DOI: 10.1080/19490976.2024.2370634 -
Journal of Hazardous Materials Oct 2023Sulfate-reducing bacteria (SRB) were effective in stabilizing Sb. However, the influence of electron donors and acceptors during SRB remediation, as well as the...
Sulfate-reducing bacteria (SRB) were effective in stabilizing Sb. However, the influence of electron donors and acceptors during SRB remediation, as well as the ecological principles involved, remained unclear. In this study, Desulfovibrio desulfuricans ATCC 7757 was utilized to stabilize soil Sb within microcosm. Humic acid (HA) or sodium sulfate (NaSO) were employed to enhance SRB capacity. The SRB+HA treatment exhibited the highest Sb stabilization rate, achieving 58.40%. Bacterial community analysis revealed that SRB altered soil bacterial diversity, community composition, and assembly processes, with homogeneous selection as the predominant assembly processes. When HA and NaSO significantly modified the stimulated microbial community succession trajectories, shaped the taxonomic composition and interactions of the bacterial community, they showed converse effect in shaping bacterial community which were both helpful for promoting dissimilatory sulfate reduction. NaSO facilitated SRB-mediated anaerobic reduction and promoted interactions between SRB and bacteria involved in nitrogen and sulfur cycling. The HA stimulated electron generation and storage, and enhanced the interactions between SRB and bacteria possessing heavy metal tolerance or carbohydrate degradation capabilities.
Topics: Antimony; Oxidation-Reduction; Soil; Biological Availability; Desulfovibrio; Bacteria; Sulfates
PubMed: 37567138
DOI: 10.1016/j.jhazmat.2023.132256 -
Revista Brasileira de Parasitologia... 2023In vitro excystation of cysts of microscopically identified Chilomastix mesnili and Retortamonas sp. isolated from Japanese macaques and Retortamonas sp. isolated from...
In vitro excystation of cysts of microscopically identified Chilomastix mesnili and Retortamonas sp. isolated from Japanese macaques and Retortamonas sp. isolated from small Indian mongooses could be induced using an established protocol for Giardia intestinalis and subsequently by culturing with H2S-rich Robinson's medium supplemented with Desulfovibrio desulfuricans. Excystation usually began 2 h after incubation in Robinson's medium. DNA was isolated from excysted flagellates after 4 h of incubation or from cultured excysted flagellates. Phylogenetic analysis based on their 18S rRNA genes revealed that two isolates of C. mesnili from Japanese macaques belonged to the same cluster as a C. mesnili isolate from humans, whereas a mammalian Retortamonas sp. isolate from a small Indian mongoose belonged to the same cluster as that of an amphibian Retortamonas spp. isolate from a 'poison arrow frog' [sequence identity to AF439347 (94.9%)]. These results suggest that the sequence homology of the 18S rRNA gene of the two C. mesnili isolates from Japanese macaques was similar to that of humans, in addition to the morphological similarity, and Retortamonas sp. infection of the amphibian type in the small Indian mongoose highlighted the possibility of the effect of host feeding habitats.
Topics: Humans; Animals; Phylogeny; Retortamonadidae; Herpestidae; Macaca fuscata; Parasites; RNA, Ribosomal, 18S
PubMed: 38055438
DOI: 10.1590/S1984-29612023070 -
Revista Espanola de Quimioterapia :... Dec 2023
Identification of curved Gram-negative rods by MALDI-TOF mass spectrometer in a patient with Fournier ́s gangrene. A bacteremia caused by Desulfovibrio desulfuricans and Escherichia coli.
Topics: Humans; Desulfovibrio desulfuricans; Escherichia coli; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Gangrene; Bacteremia; Gram-Negative Bacteria
PubMed: 37767548
DOI: 10.37201/req/026.2023 -
Biochemistry Sep 2023Nickel-substituted rubredoxin (NiRd) from has previously been shown to act as both a structural and functional mimic of the [NiFe] hydrogenase. However, improvements...
Nickel-substituted rubredoxin (NiRd) from has previously been shown to act as both a structural and functional mimic of the [NiFe] hydrogenase. However, improvements both in turnover frequency and overpotential are needed to rival the native [NiFe] hydrogenase enzymes. Characterization of a library of NiRd mutants with variations in the secondary coordination sphere suggested that protein dynamics played a substantial role in modulating activity. In this work, rubredoxin scaffolds were selected from diverse organisms to study the effects of distal sequence variation on catalytic activity. It was found that though electrochemical catalytic activity was only slightly impacted across the series, the Rd sequence from a psychrophilic organism exhibited substantially higher levels of solution-phase hydrogen production. Additionally, Eyring analyses suggest that catalytic activation properties relate to the growth temperature of the parent organism, implying that the general correlation between the parent organism environment and catalytic activity often seen in naturally occurring enzymes may also be observed in artificial enzymes. Selecting protein scaffolds from hosts that inhabit diverse environments, particularly low-temperature environments, represents an alternative approach for engineering artificial metalloenzymes.
Topics: Hydrogenase; Rubredoxins; Catalysis; Oxidation-Reduction
PubMed: 37579005
DOI: 10.1021/acs.biochem.3c00249 -
Transplantation Jul 2024Despite ongoing improvements to regimens preventing allograft rejection, most cardiac and other organ grafts eventually succumb to chronic vasculopathy, interstitial...
BACKGROUND
Despite ongoing improvements to regimens preventing allograft rejection, most cardiac and other organ grafts eventually succumb to chronic vasculopathy, interstitial fibrosis, or endothelial changes, and eventually graft failure. The events leading to chronic rejection are still poorly understood and the gut microbiota is a known driving force in immune dysfunction. We previously showed that gut microbiota dysbiosis profoundly influences the outcome of vascularized cardiac allografts and subsequently identified biomarker species associated with these differential graft outcomes.
METHODS
In this study, we further detailed the multifaceted immunomodulatory properties of protolerogenic and proinflammatory bacterial species over time, using our clinically relevant model of allogenic heart transplantation.
RESULTS
In addition to tracing longitudinal changes in the recipient gut microbiome over time, we observed that Bifidobacterium pseudolongum induced an early anti-inflammatory phenotype within 7 d, whereas Desulfovibrio desulfuricans resulted in a proinflammatory phenotype, defined by alterations in leukocyte distribution and lymph node (LN) structure. Indeed, in vitro results showed that B pseudolongum and D desulfuricans acted directly on primary innate immune cells. However, by 40 d after treatment, these 2 bacterial strains were associated with mixed effects in their impact on LN architecture and immune cell composition and loss of colonization within gut microbiota, despite protection of allografts from inflammation with B pseudolongum treatment.
CONCLUSIONS
These dynamic effects suggest a critical role for early microbiota-triggered immunologic events such as innate immune cell engagement, T-cell differentiation, and LN architectural changes in the subsequent modulation of protolerant versus proinflammatory immune responses in organ transplant recipients.
Topics: Heart Transplantation; Gastrointestinal Microbiome; Bifidobacterium; Graft Rejection; Animals; Male; Time Factors; Graft Survival; Dysbiosis; Mice, Inbred C57BL; Immunity, Innate; Immunomodulation; Phenotype; Probiotics; Lymph Nodes
PubMed: 38587506
DOI: 10.1097/TP.0000000000004939