-
Insects Apr 2024UDP-glycosyltransferases (UGTs) are a diverse superfamily of enzymes. Insects utilize uridine diphosphate-glucose (UDP-glucose) as a glycosyl donor for glycosylation in...
UDP-glycosyltransferases (UGTs) are a diverse superfamily of enzymes. Insects utilize uridine diphosphate-glucose (UDP-glucose) as a glycosyl donor for glycosylation in vivo, involved in the glycosylation of lipophilic endosymbionts and xenobiotics, including phytotoxins. UGTs act as second-stage detoxification metabolizing enzymes, which are essential for the detoxification metabolism of insecticides and benzoxazine compounds. However, the UGT genes responsible for specific glycosylation functions in are unclear at present. In this study, we utilized CRISPR/Cas9 to produce a strain to explore its possible function in governing sensitivity to chemical insecticides or benzoxazinoids. The bioassay results suggested that the strain was significantly more sensitive to chlorantraniliprole, emamectin benzoate, and benzoxazinoids than the wild-type strains. This finding suggests that the overexpression of the gene may be linked to resistance to pesticides (chlorantraniliprole and emamectin benzoate) as well as benzoxazinoids (BXDs).
PubMed: 38786870
DOI: 10.3390/insects15050314 -
Microbiology Spectrum Jul 2024Isoprenoids are a diverse family of compounds that are synthesized from two isomeric compounds, isopentenyl diphosphate and dimethylallyl diphosphate. In most bacteria,...
UNLABELLED
Isoprenoids are a diverse family of compounds that are synthesized from two isomeric compounds, isopentenyl diphosphate and dimethylallyl diphosphate. In most bacteria, isoprenoids are produced from the essential methylerythritol phosphate (MEP) pathway. The terminal enzymes of the MEP pathway IspG and IspH are [4Fe-4S] cluster proteins, and in the substrates of IspG and IspH accumulate in cells in response to O, suggesting possible lability of their [4Fe-4S] clusters. Here, we show using complementation assays in that even under anaerobic conditions, IspG and IspH are not as functional as their counterparts, requiring higher levels of expression to rescue viability. A deficit of the sulfur utilization factor (SUF) Fe-S cluster biogenesis pathway did not explain the reduced function of IspG and IspH since no improvement in viability was observed in expressing the SUF pathway or having increased expression of the SUF pathway. Complementation of single and double mutants with various combinations of and IspG and IspH indicated that optimal growth required the pairing of IspG and IspH from the same species. Furthermore, IspH conferred an O-sensitive growth defect to that could be partially rescued by co-expression of IspG. analysis showed O sensitivity of the [4Fe-4S] cluster of both IspG and IspH. Altogether, our data indicate an important role of the cognate protein IspG in IspH function under both aerobic and anaerobic conditions.
IMPORTANCE
Isoprenoids are one of the largest classes of natural products, exhibiting diversity in structure and function. They also include compounds that are essential for cellular life across the biological world. In bacteria, isoprenoids are derived from two precursors, isopentenyl diphosphate and dimethylallyl diphosphate, synthesized primarily by the methylerythritol phosphate pathway. The aerotolerant has the potential for methylerythritol phosphate pathway engineering by diverting some of the glucose that is typically efficiently converted into ethanol to produce isoprenoid precursors to make bioproducts and biofuels. Our data revealed the surprising finding that IspG and IspH need to be co-optimized to improve flux via the methyl erythritol phosphate pathway in part to evade the oxygen sensitivity of IspH.
Topics: Zymomonas; Erythritol; Escherichia coli; Bacterial Proteins; Escherichia coli Proteins; Iron-Sulfur Proteins; Terpenes; Oxidoreductases
PubMed: 38785428
DOI: 10.1128/spectrum.04256-23 -
RSC Medicinal Chemistry May 2024Most pathogenic bacteria, apicomplexan parasites and plants rely on the methylerythritol phosphate (MEP) pathway to obtain precursors of isoprenoids. 1-Deoxy-d-xylulose...
Most pathogenic bacteria, apicomplexan parasites and plants rely on the methylerythritol phosphate (MEP) pathway to obtain precursors of isoprenoids. 1-Deoxy-d-xylulose 5-phosphate synthase (DXPS), a thiamine diphosphate (ThDP)-dependent enzyme, catalyses the first and rate-limiting step of the MEP pathway. Due to its absence in humans, DXPS is considered as an attractive target for the development of anti-infectious agents and herbicides. Ketoclomazone is one of the earliest reported inhibitors of DXPS and antibacterial and herbicidal activities have been documented. This study investigated the activity of ketoclomazone on DXPS from various species, as well as the broader ThDP-dependent enzyme family. To gain further insights into the inhibition, we have prepared analogues of ketoclomazone and evaluated their activity in biochemical and computational studies. Our findings support the potential of ketoclomazone as a selective antibacterial agent.
PubMed: 38784473
DOI: 10.1039/d4md00083h -
Frontiers in Medicine 2024Crigler-Najjar syndrome (CNS) is caused by mutations in uridine 5'-diphosphate glucuronyltransferase (UGT1A1) resulting in enzyme deficiency and hyperbilirubinemia. Type...
BACKGROUND
Crigler-Najjar syndrome (CNS) is caused by mutations in uridine 5'-diphosphate glucuronyltransferase (UGT1A1) resulting in enzyme deficiency and hyperbilirubinemia. Type II CNS patients could respond to phenobarbital treatment and survive. This study presents a rare case of type II CNS.
CASE SUMMARY
The proband was a 29-year-old male patient admitted with severe jaundice. A hepatic biopsy showed bullous steatosis of the peri-central veins of the hepatic lobule, sediment of bile pigment, and mild periportal inflammation with normal liver plate structure. The type II CNS was diagnosed by routine genomic sequencing which found that the proband with the Gry71Arg/Tyr486Asp compound heterozygous mutations in the UGT1A1 gene. After treatment with phenobarbital (180 mg/day), his bilirubin levels fluctuated between 100 and 200 μmol/L for 6 months and without severe icterus.
CONCLUSION
Type II CNS could be diagnosed by routine gene sequencing and treated by phenobarbital.
PubMed: 38784231
DOI: 10.3389/fmed.2024.1354514 -
Current Opinion in Cell Biology Jun 2024Phosphoinositide 3-kinases regulate many cellular functions, including migration, growth, proliferation, and cell survival. Early studies equated the inhibition of Class... (Review)
Review
Phosphoinositide 3-kinases regulate many cellular functions, including migration, growth, proliferation, and cell survival. Early studies equated the inhibition of Class I PI3Ks with loss of; phosphatidylinositol 3,4,5-trisphosphate (PIP3), but over time, it was realised that these; treatments also depleted phosphatidylinositol 3,4-bisphosphate (PI(3,4)P2). In recent years, the; use of better tools and an improved understanding of its metabolism have allowed for the; identification of specific roles of PI(3,4)P2. This includes the production of PI(3,4)P2 and the; activation of its effector Akt2 in response to growth factor signalling. In contrast, a lysosomal pool of PI(3,4)P2 is a negative regulator of mTORC1 during growth factor deprivation. A growing body of literature also demonstrates that PI(3,4)P2 controls many dynamic plasmalemmal processes. The significance of PI(3,4)P in cell biology is increasingly evident.
Topics: Humans; Animals; Phosphatidylinositol Phosphates; Signal Transduction; Phosphatidylinositol 3-Kinases; Lysosomes
PubMed: 38776601
DOI: 10.1016/j.ceb.2024.102372 -
PLoS Genetics May 2024The helicase MCM and the ribonucleotide reductase RNR are the complexes that provide the substrates (ssDNA templates and dNTPs, respectively) for DNA replication. Here,...
The helicase MCM and the ribonucleotide reductase RNR are the complexes that provide the substrates (ssDNA templates and dNTPs, respectively) for DNA replication. Here, we demonstrate that MCM interacts physically with RNR and some of its regulators, including the kinase Dun1. These physical interactions encompass small subpopulations of MCM and RNR, are independent of the major subcellular locations of these two complexes, augment in response to DNA damage and, in the case of the Rnr2 and Rnr4 subunits of RNR, depend on Dun1. Partial disruption of the MCM/RNR interactions impairs the release of Rad52 -but not RPA-from the DNA repair centers despite the lesions are repaired, a phenotype that is associated with hypermutagenesis but not with alterations in the levels of dNTPs. These results suggest that a specifically regulated pool of MCM and RNR complexes plays non-canonical roles in genetic stability preventing persistent Rad52 centers and hypermutagenesis.
Topics: Saccharomyces cerevisiae Proteins; DNA Replication; Saccharomyces cerevisiae; DNA Damage; Cell Cycle Proteins; Rad52 DNA Repair and Recombination Protein; Genomic Instability; Ribonucleotide Reductases; DNA Repair; Protein Serine-Threonine Kinases; DNA Helicases; Minichromosome Maintenance Proteins; Replication Protein A; Ribonucleoside Diphosphate Reductase
PubMed: 38776358
DOI: 10.1371/journal.pgen.1011148 -
Scientific Reports May 2024No biomarker has yet been identified that allows accurate diagnosis and prognosis of oral cancers. In this study, we investigated the presence of key metabolites in oral...
No biomarker has yet been identified that allows accurate diagnosis and prognosis of oral cancers. In this study, we investigated the presence of key metabolites in oral cancer using proton nuclear magnetic resonance (NMR) spectroscopy to identify metabolic biomarkers of gingivobuccal oral squamous cell carcinoma (GB-OSCC). NMR spectroscopy revealed that uracil was expressed in 83.09% of tumor tissues and pyrimidine metabolism was active in GB-OSCC; these results correlated well with immunohistochemistry (IHC) and RNA sequencing data. Based on further gene and protein analyses, we proposed a pathway for the production of uracil in GB-OSCC tissues. Uridinetriphosphate (UTP) is hydrolyzed to uridine diphosphate (UDP) by CD39 in the tumor microenvironment (TME). We hypothesized that UDP enters the cell with the help of the UDP-specific P2Y6 receptor for further processing by ENTPD4/5 to produce uracil. As the ATP reserves diminish, the weakened immune cells in the TME utilize pyrimidine metabolism as fuel for antitumor activity, and the same mechanism is hijacked by the tumor cells to promote their survival. Correspondingly, the differential expression of ENTPD4 and ENTPD5 in immune and tumor cells, respectively, indicatedtheir involvement in disease progression. Furthermore, higher uracil levels were detected in patients with lymph node metastasis, indicating that metastatic potential is increased in the presence of uracil. The presence of uracil and/or expression patterns of intermediate molecules in purine and pyrimidine pathways, such asCD39, CD73, and P2Y6 receptors together with ENTPD4 and ENTPD5, hold promise as biomarker(s) for oral cancer diagnosis and prognosis.
Topics: Humans; Mouth Neoplasms; Uracil; Biomarkers, Tumor; Pyrimidines; Female; Carcinoma, Squamous Cell; Male; Middle Aged; Tumor Microenvironment; Aged; Apyrase
PubMed: 38773214
DOI: 10.1038/s41598-024-62434-z -
Chinese Clinical Oncology May 2024Pancreatic cancer is an aggressive malignancy with high mortality. At the time of diagnosis, majority of patients (80-90%) present with either locally advanced...
BACKGROUND AND OBJECTIVE
Pancreatic cancer is an aggressive malignancy with high mortality. At the time of diagnosis, majority of patients (80-90%) present with either locally advanced unresectable disease or metastatic disease. Even after curative resection, the recurrence rate remains quite high. This article aimed at reviewing the updated management of pancreatic cancer.
METHODS
We identified literature by searching Medline and PubMed from January 2010 to June 2023 using the keywords.
KEY CONTENT AND FINDINGS
A multidisciplinary approach is essential to optimize the outcomes for both curable and advanced diseases. Management of pancreatic cancer divided into resectable, borderline resectable, locally advanced, and metastatic diseases. Surgery and adjuvant chemotherapy is a standard treatment approach for resectable pancreatic cancer. The recommended adjuvant chemotherapy regimen for patients with good functional status is modified FOLFIRINOX (5-fluorouracil, folinic acid, irinotecan, and oxaliplatin). The recommended adjuvant chemotherapy regimen for patients with suboptimal functional status is gemcitabine plus capecitabine or monotherapy gemcitabine. The optimal treatment strategy for borderline resectable pancreatic cancer is still uncertain. Traditionally, upfront surgery is the choice of treatment. There is increasing evidence showing benefits of neoadjuvant therapy in borderline resectable pancreatic cancer. However, the optimal neoadjuvant treatment regimen was not certain yet. Advancement of chemotherapy has a positive impact for the survival of advanced disease. For patients with good functional status, the recommended first-line systemic chemotherapy for unresectable locally advanced disease or metastatic disease is combination chemotherapy regimens such as FOLFIRINOX, gemcitabine plus nabpaclitaxel. For patients with suboptimal functional status, the recommended first-line systemic chemotherapy for unresectable locally advanced disease or metastatic disease is gemcitabine plus capecitabine or monotherapy gemcitabine. Recently, more researches showed promising results in the use of nanoliposomal irinotecan, targeted agents such as a poly [adenosine diphosphate (ADB)-ribose] polymerase inhibitor, tyrosine receptor kinase (TRK) inhibitors, and immune checkpoint-inhibitors.
CONCLUSIONS
Pancreatic cancer is a challenging disease for management. Radical surgery itself is not enough for prolong survival. The improvement of chemotherapy, target agents and immunotherapy with multidisciplinary approach will be the only solution for improvement of survival outcome and quality of life for patients with pancreatic cancer.
PubMed: 38769794
DOI: 10.21037/cco-23-94 -
Nature Communications May 2024The mitoribosome translates mitochondrial mRNAs and regulates energy conversion that is a signature of aerobic life forms. We present a 2.2 Å resolution structure of...
The mitoribosome translates mitochondrial mRNAs and regulates energy conversion that is a signature of aerobic life forms. We present a 2.2 Å resolution structure of human mitoribosome together with validated mitoribosomal RNA (rRNA) modifications, including aminoacylated CP-tRNA. The structure shows how mitoribosomal proteins stabilise binding of mRNA and tRNA helping to align it in the decoding center, whereas the GDP-bound mS29 stabilizes intersubunit communication. Comparison between different states, with respect to tRNA position, allowed us to characterize a non-canonical L1 stalk, and molecular dynamics simulations revealed how it facilitates tRNA transitions in a way that does not require interactions with rRNA. We also report functionally important polyamines that are depleted when cells are subjected to an antibiotic treatment. The structural, biochemical, and computational data illuminate the principal functional components of the translation mechanism in mitochondria and provide a description of the structure and function of the human mitoribosome.
Topics: Humans; RNA, Transfer; Mitochondrial Ribosomes; Ligands; Molecular Dynamics Simulation; RNA, Messenger; Mitochondria; RNA, Ribosomal; Ribosomal Proteins; Guanosine Diphosphate; Polyamines; Protein Binding
PubMed: 38769321
DOI: 10.1038/s41467-024-48163-x -
International Journal of Antimicrobial... May 2024Despite its effectiveness, combination antiretroviral treatment (cART) has a limited effect on HIV DNA reservoir, which establishes early during primary HIV infection...
Despite its effectiveness, combination antiretroviral treatment (cART) has a limited effect on HIV DNA reservoir, which establishes early during primary HIV infection (PHI) and is maintained by latency, homeostatic T-cells proliferation, and residual replication. This limited effect can be associated with low drug exposure in lymphoid tissues and/or suboptimal adherence to antiretroviral drugs (ARVs). The aim of this study was to assess ARV concentrations in plasma, peripheral blood mononuclear cells (PBMCs) and lymph nodes (LNs), and their association to HIV RNA and HIV DNA decay during PHI. Participants were randomised to receive standard doses of darunavir/cobicistat (Arm I), dolutegravir (Arm II) or both (Arm III), with a backbone of tenofovir alafenamide and emtricitabine. Total HIV DNA was measured using digital-droplet PCR in PBMCs at baseline, 12 and 48 weeks. Drug concentrations in plasma and PBMCs were determined at 2, 12 and 48 weeks (LNs at 12 weeks) by UHPLC-MS/MS. Seventy-two participants were enrolled, mostly male (n=68), with a median age of 34 years and variable Fiebig stages (V-VI 57.7%, I-II 23.9%, and III-IV 18.3%). Twenty-six patients were assigned to Arm I, 27 to Arm II and 19 to Arm III. After 48 weeks, most patients had undetectable viremia, with minor differences in HIV RNA decay between arms. Patients with Fiebig I-II showed faster HIV RNA and HIV DNA decay. Intracellular tissue penetration was high for nucleoside analogues and low-moderate for darunavir and dolutegravir. Only tenofovir diphosphate concentrations in PBMCs showed correlation with HIV DNA decay. Overall, these results indicate that the timing of treatment initiation and intracellular tenofovir penetration are primary and secondary factors, respectively, affecting HIV reservoir.
PubMed: 38768738
DOI: 10.1016/j.ijantimicag.2024.107200