Acta crystallographica. Section F, Structural biology communications最新文献

{"title":"Structure of Clostridium leptum carboxyspermidine decarboxylase and comparison to homologs prevalent within the human gut microbiome.","authors":"Savannah J Jones, Dawson J Bell, Jeffrey S McFarlane","doi":"10.1107/S2053230X25000482","DOIUrl":"10.1107/S2053230X25000482","url":null,"abstract":"<p><p>Polyamines are key signalling and substrate molecules that are made by all organisms. The polyamine known as spermidine is typically made by spermidine synthase, but in many bacterial species, including 70% of human gut microbes, carboxyspermidine decarboxylase (CASDC) performs the terminal step in the production of spermidine. An X-ray crystal structure of CASDC from the human gut microbe Clostridium leptum has been solved by molecular replacement at a resolution of 1.41 Å. CASDC is a homodimer, with each monomer composed of two domains: a β/α-barrel pyridoxal 5'-phosphate-binding domain that forms most of the active site and a β-barrel domain that extends the dimeric interface and contributes to the active site of the opposing monomer. We performed a structural comparison of CASDC enzymes for 15 common genera within the human gut flora. This analysis reveals structural differences occurring in the β6/β7 loop that acts as a `flap' covering the active site and in the α9/β12 loop that is connected to the α9 helix which is thought to select substrates by their chain length. This structural analysis extends our understanding of a key enzyme in spermidine biosynthesis in many bacterial species.</p>","PeriodicalId":7029,"journal":{"name":"Acta crystallographica. Section F, Structural biology communications","volume":" ","pages":"66-72"},"PeriodicalIF":1.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11866407/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143063103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":7029,"journal":{"name":"Acta crystallographica. Section F, Structural biology communications","volume":"81 3","pages":"118-122"},"PeriodicalIF":1.1,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crystal structure of dihydroorotate dehydrogenase from Helicobacter pylori with bound flavin mononucleotide","authors":"Ashna A. Agarwal,&nbsp;John D. Georgiades,&nbsp;David M. Dranow,&nbsp;Donald D. Lorimer,&nbsp;Thomas Edwards,&nbsp;Kayleigh F. Barrett,&nbsp;Justin K. Craig,&nbsp;Wesley C. Van Voorhis,&nbsp;Peter J. Myler,&nbsp;Craig L. Smith","doi":"10.1107/S2053230X25000858","DOIUrl":"10.1107/S2053230X25000858","url":null,"abstract":"<p><i>Helicobacter pylori</i> is the primary causative agent of peptic ulcer disease, among other gastrointestinal ailments, and currently affects over half of the global population. Although some treatments exist, growing resistance to these drugs has prompted efforts to develop novel approaches to fighting this pathogen. To generate many of the nucleotides essential to biochemical processes, <i>H. pylori</i> relies exclusively on the <i>de novo</i> biosynthesis of these molecules. Recent drug-discovery efforts have targeted the first committed step of this pathway, catalysed by a class 2 dihydroorotate dehydrogenase (DHODH). However, these initiatives have been limited by the lack of a crystal structure. Here, we detail the crystal structure of <i>H. pylori</i> DHODH (<i>Hp</i>DHODH) at 2.25 Å resolution (PDB entry 6b8s). We performed a large-scale bioinformatics search to find evolutionary homologs. Our results indicate that <i>Hp</i>DHODH shows high conservation of both sequence and structure in its active site. We identified key polar interactions between the <i>Hp</i>DHODH protein and its requisite flavin mononucleotide (FMN) cofactor, identifying amino-acid residues that are critical to its function. Most notably, we found that <i>Hp</i>DHODH maintains several structural features that allow it to associate with the inner membrane and utilize ubiquinone to achieve catalytic turnover. We discovered a hydrophobic channel that runs from the putative membrane interface on the N-terminal microdomain to the core of the protein. We predict that this channel establishes a connection between the ubiquinone pool in the membrane and the FMN in the active site. These findings provide a structural explanation for the competitive inhibition of ubiquinone by pyrazole-based compounds that was determined biochemically in other studies. Understanding this mechanism may facilitate the development of new drugs targeting this enzyme and push the effort to find a resistance-free treatment for <i>H. pylori</i>.</p>","PeriodicalId":7029,"journal":{"name":"Acta crystallographica. Section F, Structural biology communications","volume":"81 3","pages":"108-117"},"PeriodicalIF":1.1,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143439351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":7029,"journal":{"name":"Acta crystallographica. Section F, Structural biology communications","volume":"81 3","pages":"123"},"PeriodicalIF":1.1,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":7029,"journal":{"name":"Acta crystallographica. Section F, Structural biology communications","volume":"81 3","pages":"95-100"},"PeriodicalIF":1.1,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":7029,"journal":{"name":"Acta crystallographica. Section F, Structural biology communications","volume":"81 3","pages":"101-107"},"PeriodicalIF":1.1,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":7029,"journal":{"name":"Acta crystallographica. Section F, Structural biology communications","volume":"81 3","pages":"85-94"},"PeriodicalIF":1.1,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":7029,"journal":{"name":"Acta crystallographica. Section F, Structural biology communications","volume":"81 3","pages":"73-84"},"PeriodicalIF":1.1,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":7029,"journal":{"name":"Acta crystallographica. Section F, Structural biology communications","volume":"81 3","pages":"66-72"},"PeriodicalIF":1.1,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The structure of His15 acetamide-modified hen egg-white lysozyme: a nice surprise from an old friend.","authors":"Jose Malanho da Silva, Jose Lanuza, Francesco Bruno, Vito Calderone, Enrico Ravera","doi":"10.1107/S2053230X2500010X","DOIUrl":"10.1107/S2053230X2500010X","url":null,"abstract":"<p><p>Hen egg-white lysozyme (HEWL) is a small polycationic protein which is highly soluble and stable. This has led to it becoming a `molecular laboratory' where chemical biological operations and structural techniques are tested. To date, HEWL accounts for 1233 PDB entries, roughly 0.5% of the total, making it the best-represented protein in the PDB. With the aim of unambiguously identifying the N atom of the His15 side chain that is most reactive towards iodoacetamide, the structure of chemically modified HEWL was determined by crystallizing it using the `15 minutes lysozyme' protocol. This protocol invariably yields tetragonal crystals of the unmodified protein. To our surprise, we found that the crystals of the modified protein had similar unit-cell parameters but that refinement was only possible when considering an orthorhombic system.</p>","PeriodicalId":7029,"journal":{"name":"Acta crystallographica. Section F, Structural biology communications","volume":" ","pages":"41-46"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11783178/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142968938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}