Protein Science最新文献_第2页

Structural basis of secreted acid phosphatase polymerization in the Leishmania parasite. 利什曼原虫分泌酸性磷酸酶聚合的结构基础。

IF 5.2 3区生物学

Protein Science Pub Date : 2026-05-01 DOI: 10.1002/pro.70591

Priyanka Bose, Irit Dahan, Alexander Upcher, Ran Zalk, Iris Grossman-Haham

{"title":"Structural basis of secreted acid phosphatase polymerization in the Leishmania parasite.","authors":"Priyanka Bose, Irit Dahan, Alexander Upcher, Ran Zalk, Iris Grossman-Haham","doi":"10.1002/pro.70591","DOIUrl":"10.1002/pro.70591","url":null,"abstract":"Enzymes that assemble into filaments typically transition between protomeric and polymeric states in response to cellular conditions. In contrast, the secreted acid phosphatase (SAP) of Leishmania, one of the most abundant extracellular glycoproteins produced by the parasite and regarded as a major virulence factor in the neglected tropical disease leishmaniasis, exhibits fundamentally different behavior. Depending on the species, SAP forms either highly stable extracellular filaments or remains exclusively as globular particles, with no evidence of reversible interconversion. This binary assembly pattern is particularly intriguing given that SAP orthologs that differ in their ability to polymerize share a high degree of sequence conservation, leaving the molecular determinants of filament formation unknown. Here, we report the cryo-EM structure of filamentous Leishmania mexicana SAP to a global resolution of 3.0 Å. The structure resolves the multilevel organization of the enzyme, from individual catalytic phosphatase domains and their unique substrate-binding pockets to the formation of homodimeric protomers, the decoration with N-linked glycans, and the supramolecular organization into filaments. At the core of the polymerization interface, we identified a unique β-hairpin motif that has not been observed in any other phosphatase or enzyme filament, which provides exceptional filament stability. By integrating structural data with comparative sequence analysis and machine-learning-based structure predictions, we define the molecular basis for the species-specific assembly behaviors observed across Leishmania SAPs. This work establishes the principles governing SAP filament formation and provides a framework for understanding its evolution, enzymatic function, and potential applications.","PeriodicalId":20761,"journal":{"name":"Protein Science","volume":"35 5","pages":"e70591"},"PeriodicalIF":5.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13096585/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147729825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Structure-guided optimization of SLY1 expression and purification in Escherichia coli. 结构导向优化大肠杆菌中SLY1的表达和纯化。

IF 5.2 3区生物学

Protein Science Pub Date : 2026-05-01 DOI: 10.1002/pro.70592

Souleïmen Jmii, William Bouard, Mathilde Rochas, François Dragon, Laurent Cappadocia

{"title":"Structure-guided optimization of SLY1 expression and purification in Escherichia coli.","authors":"Souleïmen Jmii, William Bouard, Mathilde Rochas, François Dragon, Laurent Cappadocia","doi":"10.1002/pro.70592","DOIUrl":"10.1002/pro.70592","url":null,"abstract":"The SCFSLY1 ubiquitin ligase complex is a key regulator of gibberellin signaling, mediating the degradation of DELLA proteins through targeted ubiquitination. To enable detailed biochemical and structural studies of this complex, efficient recombinant production of SLY1 and its adaptor ASK1 is essential. In this study, we optimized the co-expression and purification of the ASK1-SLY1 complex in Escherichia coli, focusing on molecular determinants that influence solubility, stability, and protein interaction. Hydrophobicity analyses and AlphaFold structural modeling of ASK1 and SLY1 identified prominent hydrophobic surfaces, particularly around helix α7 of SLY1, which are involved in DELLA binding and potentially driving aggregation during purification. Based on these insights, we adopted a co-expression strategy with an MBP tag fused at the N-terminal end of one partner, which significantly enhanced solubility and enabled successful isolation of the intact ASK1-SLY1 complex. Overall, this work presents an optimized protocol for recombinant production of the ASK1-SLY1 complex and provides structural rationale for overcoming key challenges in its expression and purification.","PeriodicalId":20761,"journal":{"name":"Protein Science","volume":"35 5","pages":"e70592"},"PeriodicalIF":5.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13096574/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147729769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The virus lesson: Teaching viral structure and quasi-symmetry in mixed reality. 病毒的教训：在混合现实中教授病毒结构和准对称性。

IF 5.2 3区生物学

Protein Science Pub Date : 2026-05-01 DOI: 10.1002/pro.70570

Adam Gardner, Fabien Cannac, Quentin Tallon, Arthur Olson, Ludovic Autin

{"title":"The virus lesson: Teaching viral structure and quasi-symmetry in mixed reality.","authors":"Adam Gardner, Fabien Cannac, Quentin Tallon, Arthur Olson, Ludovic Autin","doi":"10.1002/pro.70570","DOIUrl":"10.1002/pro.70570","url":null,"abstract":"Traditional approaches to teaching structural biology struggle to capture the dynamic, three-dimensional nature of biomolecular structures. Viral capsids, which employ quasi-symmetric arrangements, are especially difficult to conceptualize at the human scale. While physical models can illustrate geometry, they are costly, static, and disconnected from the digital domain. Recent advances in mixed reality (MR) offer an opportunity to overcome these limitations by combining immersion, interactivity, and collaboration. We present Virus Lesson, an MR application designed to teach viral quasi-symmetry through shared immersive experiences. Developed in Unity and optimized for standalone MR headsets such as the Meta Quest 3/3S, the platform integrates multiplayer networking to allow students and instructors to co-localize in the same virtual classroom. Activities include interactive exploration of virus size and composition, dissection of capsids to reveal encapsidated RNA, construction of quasi-symmetric shells using Caspar-Klug triangulation theory, and antibody-antigen recognition tasks. Educational design elements such as spatially separated \"learning stations,\" memory palace techniques, and scaffolded problem-solving guide learners through increasingly complex concepts. Pilot demos with participants of all ages showed high engagement, improved comprehension of virus structure, quasi-symmetry, and immunological interactions, and strong appreciation of collaborative learning in MR. The Virus Lesson demonstrates that MR can enhance understanding of challenging structural biology concepts while providing a scalable framework for interactive, human-scale education in biomolecular sciences.","PeriodicalId":20761,"journal":{"name":"Protein Science","volume":"35 5","pages":"e70570"},"PeriodicalIF":5.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13073050/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147676085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multivalent recognition of ferritin by full-length NCOA4 enables robust ferritinophagy. 全长NCOA4对铁蛋白的多价识别使铁蛋白自噬变得强大。

IF 5.2 3区生物学

Protein Science Pub Date : 2026-05-01 DOI: 10.1002/pro.70589

Ayush K Srivastava, Genki Terashi, Rosa Viner, Audrey Kishishita, Arun P Wiita, Anitha Rajendran, Yeonni Zoo, Georgia C Papaefthymiou, Daisuke Kihara, Fadi Bou-Abdallah

{"title":"Multivalent recognition of ferritin by full-length NCOA4 enables robust ferritinophagy.","authors":"Ayush K Srivastava, Genki Terashi, Rosa Viner, Audrey Kishishita, Arun P Wiita, Anitha Rajendran, Yeonni Zoo, Georgia C Papaefthymiou, Daisuke Kihara, Fadi Bou-Abdallah","doi":"10.1002/pro.70589","DOIUrl":"https://doi.org/10.1002/pro.70589","url":null,"abstract":"Ferritinophagy is a central pathway in cellular iron homeostasis, yet the molecular basis by which the selective autophagy receptor NCOA4 recognizes and engages ferritin remains poorly defined, largely due to the long-standing inability of working with a soluble form of the full-length human NCOA4 (NCOA4FL). Here, we present an integrated biochemical and biophysical analysis of NCOA4FL and its interaction with human ferritin, complemented by structure-guided modeling. We show that NCOA4FL is predominantly intrinsically disordered and exists in a dynamic monomer-dimer equilibrium in solution, yet forms a stable, nanomolar-affinity complex with ferritin. Using crosslinking mass spectrometry, together with integrative modeling informed by low-resolution structural context, we demonstrate that NCOA4FL engages ferritin through a multivalent, distributed interface that is not confined to a short motif, in contrast to prior fragment-based models. Multiple interaction hotspots are identified on ferritin helices B and D, while NCOA4FL employs both central and terminal regions to wrap around the ferritin nanocage, enabling avidity-driven recognition. We further show that NCOA4FL coordinates a redox-sensitive [4Fe-4S] cluster, introducing a chemically defined feature that may contribute to its conformational plasticity and regulation. Together, these findings establish NCOA4FL as a flexible, multivalent ferritin receptor and define the recognition logic by which ferritin assemblies are selectively recognized and targeted for lysosomal degradation during ferritinophagy.","PeriodicalId":20761,"journal":{"name":"Protein Science","volume":"35 5","pages":"e70589"},"PeriodicalIF":5.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13114776/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147778975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tetrameric hotdog-fold structure and catalytic mechanism of the SaPaaI thioesterase from Staphylococcus aureus. 金黄色葡萄球菌SaPaaI硫酯酶的四聚体热狗折叠结构及其催化机理。

IF 5.2 3区生物学

Protein Science Pub Date : 2026-05-01 DOI: 10.1002/pro.70583

Yogesh Khandokar, Parul Srivastava, Renate H M Schwab, Ashish Sethi, Naveen Vankadari, Jade K Forwood

{"title":"Tetrameric hotdog-fold structure and catalytic mechanism of the SaPaaI thioesterase from Staphylococcus aureus.","authors":"Yogesh Khandokar, Parul Srivastava, Renate H M Schwab, Ashish Sethi, Naveen Vankadari, Jade K Forwood","doi":"10.1002/pro.70583","DOIUrl":"https://doi.org/10.1002/pro.70583","url":null,"abstract":"Acyl-CoA thioesterases hydrolyse thioester bonds to release free fatty acyl chains and coenzyme A (CoA), thereby regulating lipid metabolism, signaling, and membrane homeostasis. Here, we present the structural and functional characterization of the Paal-like thioesterase SAV0944 (SaPaaI) from Staphylococcus aureus. SaPaaI adopts a class-II hotdog fold comprising six β-strands wrapped around a central α-helix and assembles as a tetrameric dimer-of-dimers, as determined by x-ray crystallography and analytical size-exclusion chromatography. Enzyme assays using a panel of acyl-CoA substrates identify benzoyl-CoA as the preferred substrate. Guided by structural alignment with homologous thioesterases, Gln32 and Glu47 were identified as essential catalytic residues; alanine substitutions at either position abolished activity without perturbing the global fold. The crystal structure revealed asymmetric CoA binding, with only two monomers in the tetramer displaying well-defined ligand density. Comparison of CoA-bound and ligand-free monomers showed that Gln32 undergoes a ~102° conformational rotation that opens the substrate tunnel in the bound state, whereas the corresponding unliganded monomers adopt a closed conformation that sterically occludes the pocket. This mutually exclusive positioning of Gln32 within each dimer provides structural evidence for half-of-the-sites behavior, suggesting that SaPaaI employs a ligand-induced gating mechanism that modulates substrate access. Together, these findings establish SaPaaI as a benzoyl-CoA-selective thioesterase with a noncanonical catalytic configuration and uncover an asymmetric, Gln32-dependent gating mechanism that contributes to substrate specificity in this essential S. aureus enzyme.","PeriodicalId":20761,"journal":{"name":"Protein Science","volume":"35 5","pages":"e70583"},"PeriodicalIF":5.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13114782/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147779130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Detection of gas bubbles and local voids in molecular simulations using burbuja. 布贾分子模拟中气泡和局部空洞的探测。

IF 5.2 3区生物学

Protein Science Pub Date : 2026-05-01 DOI: 10.1002/pro.70562

Abraham Muñiz-Chicharro, Lane W Votapka, Rommie E Amaro

引用次数: 0

copick: An open dataset interface and toolkit for collaborative annotation and analysis of cryo-electron tomography data. copick：一个开放的数据集接口和工具包，用于协同注释和分析低温电子断层扫描数据。

IF 5.2 3区生物学

Protein Science Pub Date : 2026-05-01 DOI: 10.1002/pro.70578

Utz Heinrich Ermel, Jonathan Schwartz, Zhuowen Zhao, Daniel Ji, Ariana Peck, Yue Yu, Mohammadreza Paraan, Bridget Carragher, Achilleas S Frangakis, Kyle I S Harrington

{"title":"copick: An open dataset interface and toolkit for collaborative annotation and analysis of cryo-electron tomography data.","authors":"Utz Heinrich Ermel, Jonathan Schwartz, Zhuowen Zhao, Daniel Ji, Ariana Peck, Yue Yu, Mohammadreza Paraan, Bridget Carragher, Achilleas S Frangakis, Kyle I S Harrington","doi":"10.1002/pro.70578","DOIUrl":"10.1002/pro.70578","url":null,"abstract":"Cryo-electron tomography (cryoET) enables visualization of macromolecular complexes within intact cellular environments. Continued improvements in instrumentation, sample preparation, and data-processing pipelines have increased both the scale and the complexity of cryoET datasets, making manual analysis challenging. To support scalable, collaborative annotation, we developed copick, an open-source dataset application programming interface (API) and accompanying tool suite for cryoET analysis. Copick provides standardized access to tomograms, segmentations, point annotations, meshes, and feature maps across local storage, high-performance computing systems, cloud platforms, and public repositories. Plugins for napari and ChimeraX enable human-in-the-loop workflows for particle picking, segmentation, inspection of machine-learning outputs, and project-level collaboration. A multi-resolution Open Microscopy Environment (OME)-Zarr architecture supports responsive visualization and cross-platform access. Copick additionally provides a Model Context Protocol interface enabling automated generation of annotation-curation pipelines using natural-language instructions. Together, these tools support reproducible, scalable, and collaborative cryoET analysis.","PeriodicalId":20761,"journal":{"name":"Protein Science","volume":"35 5","pages":"e70578"},"PeriodicalIF":5.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13090584/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147717744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

T3SS effector and regulator discovery by predicting interacting partners of T3SS chaperones in Pseudomonas aeruginosa. 通过预测铜绿假单胞菌中T3SS伴侣的相互作用伙伴发现T3SS效应因子和调节因子。

IF 5.2 3区生物学

Protein Science Pub Date : 2026-05-01 DOI: 10.1002/pro.70551

Jing Zhang

{"title":"T3SS effector and regulator discovery by predicting interacting partners of T3SS chaperones in Pseudomonas aeruginosa.","authors":"Jing Zhang","doi":"10.1002/pro.70551","DOIUrl":"10.1002/pro.70551","url":null,"abstract":"Pseudomonas aeruginosa is a prominent opportunistic pathogen whose virulence is closely linked to its Type III Secretion System (T3SS), a specialized apparatus that injects effector proteins into host cells. T3SS chaperones are essential for stabilizing, delivering, and regulating T3SS expression. Multiple T3SS effectors and regulators have been identified and characterized in the P. aeruginosa reference strains such as PAO1 and PA14. However, the full repertoire of T3SS chaperones and their interacting partners in the pan-genomes of thousands of P. aeruginosa isolates remains to be explored. Here, I systematically screened over 15,000 high-quality P. aeruginosa genomes to identify T3SS chaperones using structure-assisted homology searches. Subsequently, I applied AlphaFold2 and AlphaFold3 to predict protein-protein interactions between chaperones and other proteins in the pan-proteome. A benchmark analysis suggests that our approach can effectively distinguish true interacting partners of T3SS chaperones on a proteome-wide scale. Our analysis identified several high-confidence candidate T3SS effectors and regulators, including putative lipoproteins, calcium-binding proteins, and transcriptional regulators, that are potentially involved in host adaptation, T3SS regulation, and virulence modulation. I also found T3SS chaperone homologs that may serve as non-cognate antitoxins or virulence regulators. These findings demonstrate the power of combining genomics with deep learning-based structure and interaction prediction to uncover hidden components of bacterial virulence pathways and provide new targets for antimicrobial development.","PeriodicalId":20761,"journal":{"name":"Protein Science","volume":"35 5","pages":"e70551"},"PeriodicalIF":5.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13092808/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147723587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Single-molecule force spectroscopy discovers a dual-binding mode in the hCG-mediated activation of LHCGR. 单分子力谱发现hcg介导的LHCGR激活存在双结合模式。

IF 5.2 3区生物学

Protein Science Pub Date : 2026-05-01 DOI: 10.1002/pro.70584

Qian Han, Yilong He, Ziyang Yao, Xuan Peng, Yutong Wang, Ziwei Huang, Shuaijian Dai, Niandong Jiao, Jian Qiu, Lizhi Leng, Zhuxin Dong

{"title":"Single-molecule force spectroscopy discovers a dual-binding mode in the hCG-mediated activation of LHCGR.","authors":"Qian Han, Yilong He, Ziyang Yao, Xuan Peng, Yutong Wang, Ziwei Huang, Shuaijian Dai, Niandong Jiao, Jian Qiu, Lizhi Leng, Zhuxin Dong","doi":"10.1002/pro.70584","DOIUrl":"10.1002/pro.70584","url":null,"abstract":"Human Chorionic Gonadotropin (hCG) mediates the activation of luteinizing hormone/choriogonadotropin receptor (LHCGR) by binding to it, which is critical for human reproduction. However, specific dynamics of such interaction remain ambiguous. Herein, we utilized single-molecule force spectroscopy (SMFS) to carry out quantitative analysis during the binding between hCG and separate LHCGR domains. Two distinct binding mechanisms were detected within the LHCGR extracellular domain (ECD), associated with the hinge loop and leucine-rich repeats (LRRs), respectively. Compared to the hinge loop, the LRRs-hCG interaction exhibited a bimodal energy landscape with an exceptionally stable outer barrier (binding lifetime τ 18.4 vs. 0.67 s). Furthermore, the same dual-binding mode was observed from full-length LHCGR on membranes of living cells, confirming the physiological relevance of these distinct binding mechanisms. To explore beyond the experimental measurements, we performed molecular dynamics simulations. The computational outcomes revealed a sequential, three-step hCG/LHCGR dissociation process during which electrostatic forces could facilitate hCG/hinge loop interactions multiple times. Consequently, the anchorage-dependent activation of LHCGR mediated by hCG was specified. Overall, our SMFS-based strategy deciphers the dynamic recognition code of hCG/LHCGR interaction and provides a new clue for developing therapeutic strategies targeting glycoprotein hormone receptors.","PeriodicalId":20761,"journal":{"name":"Protein Science","volume":"35 5","pages":"e70584"},"PeriodicalIF":5.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13096575/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147729772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Substrate selectivity of human histidine methyltransferase METTL9. 人组氨酸甲基转移酶METTL9的底物选择性。

IF 5.2 3区生物学

Protein Science Pub Date : 2026-05-01 DOI: 10.1002/pro.70590

Sadaf Ahmad, Laust Moesgaard, Christian W Tornøe, Paulina Emmel, Klaudia Slusarczyk, Jakub Drozak, Jacob Kongsted, Jasmin Mecinović

{"title":"Substrate selectivity of human histidine methyltransferase METTL9.","authors":"Sadaf Ahmad, Laust Moesgaard, Christian W Tornøe, Paulina Emmel, Klaudia Slusarczyk, Jakub Drozak, Jacob Kongsted, Jasmin Mecinović","doi":"10.1002/pro.70590","DOIUrl":"10.1002/pro.70590","url":null,"abstract":"Methylation of histidine residues in zinc transporters by histidine methyltransferase METTL9 plays an important role in modulating their metal-binding properties. Here, we report synthetic, enzymatic, and computational studies on human METTL9-catalyzed Nπ-methylation of His375 in zinc transporter SLC39A5-derived peptides in which the histidine substrate and its neighboring residues are substituted by chemically and structurally diverse proteinogenic and nonproteinogenic amino acids. Our work reveals that the xHxH motif (residues 372-375) is essential for efficient Nπ-histidine methyltransferase METTL9 catalysis. We demonstrate that human METTL9 has an exceptionally narrow substrate scope towards His375 and does not catalyze methylation of simple histidine mimics in the SLC39A5 peptide. Moreover, METTL9 recognizes only 2-pyridylalanine, 3-(4-thiazolyl)alanine and backbone N-methylated histidine residues at position 373 in addition to the natural His373 residue. METTL9 has also a capacity to recognize a few simplest mimics of Ser374 and Gly372 residues in the SLC39A5 sequence. Molecular dynamics simulations support the experimental findings and deliver a comprehensive structural basis on the significance of the xHxH motif for stable METTL9-SLC39A5 complex formation and efficient METTL9 catalysis. Overall, this study provides evidence for different substrate selectivities of human histidine methyltransferase METTL9, the knowledge important from basic molecular and biomedical perspectives.","PeriodicalId":20761,"journal":{"name":"Protein Science","volume":"35 5","pages":"e70590"},"PeriodicalIF":5.2,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13125359/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147779028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0