Monidipa Konar , Bhavneet Kaur , Uttam Chand Saini , Sanjay K. Bhadada , Sadhna Sharma
{"title":"Synovial fluid glycoproteome profiling in knee osteoarthritis: Molecular insights into type 2 diabetes-associated biomarkers and therapeutic targets","authors":"Monidipa Konar , Bhavneet Kaur , Uttam Chand Saini , Sanjay K. Bhadada , Sadhna Sharma","doi":"10.1016/j.bbapap.2025.141067","DOIUrl":"10.1016/j.bbapap.2025.141067","url":null,"abstract":"<div><div>Type 2 diabetes mellitus (T2DM) and Osteoarthritis (OA) share common risk factors like age, obesity and hypertension. Currently, 52 % of diabetic patients suffer from arthritis. Diabetes facilitates OA by altering lipid metabolism, levels of adipokines & cytokines, accumulation of advanced glycation end products, etc., which affects cartilage & bone health. However, the molecular mechanisms of the association of OA with T2DM remain unexplored. Since diabetes greatly affects the glycosylation status of proteins, the present study focused on identifying glycoproteins that could serve as diagnostic and prognostic markers for identifying osteoarthritis in diabetic individuals by LC-MS/MS. Comparative proteomic analysis revealed 20 significantly altered glycoproteins; among them, thyroxine-binding globulin (THBG), alpha-1-antitrypsin (A1AT), fibrinogen gamma chain (FGG) and angiotensinogen (AGT) were further validated. THBG, A1AT and AGT showed promising potential to identify the comorbid condition in serum and synovial fluid, however, ROC analysis identified THBG as the best candidate glycoprotein marker. Upregulation of THBG in OADM disrupts the bone remodeling cycle, degrades insulin, and promotes the expression of GLUT-1 and MMP-9. Overall, THBG could also serve as a therapeutic target for reducing the progression of osteoarthritis and alleviating pain and bone stiffness associated with the disease.</div></div>","PeriodicalId":8760,"journal":{"name":"Biochimica et biophysica acta. Proteins and proteomics","volume":"1873 4","pages":"Article 141067"},"PeriodicalIF":2.5,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143742091","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":"Efficient production of a novel recombinant fusion protein of EIEC effector IpaD and EGFP: Biophysical characterization and functional studies","authors":"Sudeshna Halder, Namita Jaiswal, Salari Charan Balajee, Nibedita Mahata","doi":"10.1016/j.bbapap.2025.141066","DOIUrl":"10.1016/j.bbapap.2025.141066","url":null,"abstract":"<div><div>The conserved invasion plasmid antigen D (IpaD) protein demonstrates broad protective capabilities against bacillary dysentery caused by Enteroinvasive <em>Escherichia coli</em> (EIEC) and <em>Shigella</em>. However, the instability of the IpaD protein at room temperature limits its therapeutic potential. The stabilization and efficient production of functional recombinant proteins remain critical challenges in therapeutic and vaccine development. This study presents a novel fluorescence fusion strategy for producing a stable IpaD-EGFP recombinant protein using a flexible linker (GGGGS)₃. The fusion technique enhances the expression level (∼53 %), solubility (∼77 %), and stability of the IpaD-EGFP fusion protein. Biophysical characterization studies suggest that the IpaD-EGFP fusion protein is stable at refrigerated temperatures for extended periods and up to 1 month at 25 °C. The IpaD-EGFP protein triggers apoptosis in Raw 267.4 cells through activation of caspases 3/7. The protein also induces antibody response in BALB/c mice indicating its immunogenicity. Together, these findings indicate that IpaD-EGFP generated in this study is a potential approach for the design and production of stable IpaD-based protein therapeutics, breaking the expensive “cold chain” of continuous refrigeration. Fusion approach significantly enhanced the solubility, yield, and stability of IpaD, while enabling efficient purification.</div></div>","PeriodicalId":8760,"journal":{"name":"Biochimica et biophysica acta. Proteins and proteomics","volume":"1873 4","pages":"Article 141066"},"PeriodicalIF":2.5,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630132","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}
Amanda Bartkowiak, Ewa Szczesny-Malysiak, Jakub Dybas
{"title":"Tracking heme biology with resonance Raman spectroscopy","authors":"Amanda Bartkowiak, Ewa Szczesny-Malysiak, Jakub Dybas","doi":"10.1016/j.bbapap.2025.141065","DOIUrl":"10.1016/j.bbapap.2025.141065","url":null,"abstract":"<div><div>Heme proteins are a large group of biomolecules with heme incorporated as a prosthetic group. Apart from cytochromes present in almost all cell types, many other specific heme proteins are expressed in different kinds of cells, e.g. hemoglobin in the erythrocytes, myoglobin (skeletal and vascular smooth muscle cells), cytoglobin (fibroblasts) and neuroglobin (neurons and retina). Among their wide and diverse biological functions, the most important is their unique ability to bind, store, and transport gaseous molecules, such as oxygen, carbon monoxide, and nitric oxide. Resonance Raman (RR) spectroscopy is an exceptional analytical tool that allows for qualitative and quantitative characterization of heme proteins in biological systems. Due to its high sensitivity, even subtle structural alterations of the heme group can be monitored and tracked during cellular processes. Resonance Raman excitation within the Soret absorption band (390–440 nm) provides rich information on the environment of heme's active site, allowing differentiation of the iron ion oxidation and spin states, and tracking the movement of the porphyrin ring plane in response to the changes in oxygenation status. Herein, we summarize and discuss recent developments in RR applications aimed to link the structure-function relationship of heme proteins within biological systems, connected, e.g., with the formation of hemoglobin (Hb) adducts (nitrosylhemoglobin, cyanhemoglobin, sulfhemoglobin), irreversible Hb alterations deteriorating oxygen binding and differentiation of heme proteins oxidation state within live cells in situ.</div></div>","PeriodicalId":8760,"journal":{"name":"Biochimica et biophysica acta. Proteins and proteomics","volume":"1873 3","pages":"Article 141065"},"PeriodicalIF":2.5,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497595","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}
Sk Alim , Sudheer K. Cheppali , Sonali S. Pawar, Musti J. Swamy
{"title":"DSP-1, the major fibronectin type-II protein of donkey seminal plasma is a small heat-shock protein and exhibits chaperone-like activity against thermal and oxidative stress","authors":"Sk Alim , Sudheer K. Cheppali , Sonali S. Pawar, Musti J. Swamy","doi":"10.1016/j.bbapap.2025.141064","DOIUrl":"10.1016/j.bbapap.2025.141064","url":null,"abstract":"<div><div>Fibronectin type-II (FnII) proteins are major constituents in the seminal plasma of many mammals and play a crucial role in sperm capacitation. Additionally, the seminal FnII proteins from bull and horse exhibit chaperone-like activity (CLA), by acting as small heat shock proteins (<em>shsp</em>s). The present work demonstrates that the major FnII protein of donkey seminal plasma, DSP-1 exhibits CLA with broad specificity and protects various client proteins such as alcohol dehydrogenase, lactate dehydrogenase and enolase against thermal and oxidative stress. Binding of phosphorylcholine (PrC) – the head group moiety of choline phospholipids, which are the physiological ligands of DSP-1 – decreased the CLA whereas binding of 1,2-dioleoyl-<em>sn</em>-glycero-3-phospholcholine (DOPC) increased the CLA. Biophysical studies suggested that these contrasting effects on the CLA by phosphorylcholine and diacyl phosphatidylcholine could be attributed to changes in the surface hydrophobicity of DSP-1 upon binding to these ligands. Interestingly, binding of PrC reduced DSP-1 tetramers to monomers with lower surface hydrophobicity, whereas binding to DOPC liposomes increased its surface hydrophobicity. These results, which demonstrate that DSP-1 exhibits CLA and functions as a molecular chaperone, expand the family of mammalian seminal FnII proteins that function as <em>shsp</em>s.</div></div>","PeriodicalId":8760,"journal":{"name":"Biochimica et biophysica acta. Proteins and proteomics","volume":"1873 3","pages":"Article 141064"},"PeriodicalIF":2.5,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143432278","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}
Pascal Rey , Nicolas Rouhier , Chloé Carassus , Arjan de Groot , Laurence Blanchard
{"title":"Participation of a cysteine tetrad in the recycling mechanism of methionine sulfoxide reductase A from radiation-tolerant Deinococcus bacteria","authors":"Pascal Rey , Nicolas Rouhier , Chloé Carassus , Arjan de Groot , Laurence Blanchard","doi":"10.1016/j.bbapap.2025.141063","DOIUrl":"10.1016/j.bbapap.2025.141063","url":null,"abstract":"<div><div>Methionine oxidation leads to the formation of methionine sulfoxide (MetO), which is reduced back to Met by methionine sulfoxide reductases (Msrs). The catalytic mechanism used by A-type Msr (MsrA) for MetO reduction requires a catalytic cysteine (Cys), which is converted to a sulfenic acid. In general, two resolving Cys are required for the regeneration of the catalytic Cys forming two consecutive disulfide bridges, the last one being efficiently reduced by thioredoxin (Trx). Here, we performed the biochemical characterization of MsrA from <em>Deinococcus deserti</em>. It possesses four Cys, two present in the active site motif (18 and 21) and two distal ones (53 and 163). We produced MsrA variants mutated for these cysteines and analyzed their capacity to reduce MetO in the presence of the NADPH-Trx reductase/Trx system, their ability to form heterodimers with Trxs, and their redox status after incubation with MetO. We show that all four Cys are involved in the regeneration process of enzyme activity by Trx. After MetO reduction by Cys18, a first disulfide bridge is formed with Cys21. A second disulfide involving Cys21 with either Cys53 or Cys163 is reduced by Trx, and a third Cys53-Cys163 disulfide can be formed and also reduced by Trx. These findings highlighting for the first time the involvement of a Cys tetrad in the catalytic and regeneration mechanisms for a MsrA are placed in a structural context by performing 3D modelling and discussed in relation to the known recycling mechanisms involving a Cys triad.</div></div>","PeriodicalId":8760,"journal":{"name":"Biochimica et biophysica acta. Proteins and proteomics","volume":"1873 3","pages":"Article 141063"},"PeriodicalIF":2.5,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143389955","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}
Mikhail Matveyenka , Abid Ali , Charles L. Mitchell , Mikhail Sholukh , Dmitry Kurouski
{"title":"Elucidation of cytotoxicity of α-Synuclein fibrils on immune cells","authors":"Mikhail Matveyenka , Abid Ali , Charles L. Mitchell , Mikhail Sholukh , Dmitry Kurouski","doi":"10.1016/j.bbapap.2024.141061","DOIUrl":"10.1016/j.bbapap.2024.141061","url":null,"abstract":"<div><div>Progressive aggregation of α-synuclein (α-Syn), a small cytosolic protein involved in cell vesicle trafficking, in the midbrain, hypothalamus, and thalamus is linked to Parkinson's disease (PD). Amyloid oligomers and fibrils formed as a result of such aggregation are highly toxic to neurons. However, it remains unclear whether amyloid-induced toxicity of neurons is the primary mechanism of the progressive neurodegeneration observed upon PD. In the current study, we investigated cytotoxicity exerted by α-Syn fibrils formed in the lipid-free environment, as well as in the presence of two phospholipids, on macrophages, dendritic cells, and microglia. We found that α-Syn fibrils are far more toxic to dendritic cells and microglia compared to neurons. We also observe low toxicity levels of such amyloids to macrophages. Real-time polymerase chain reaction (RT-PCR) results suggest that toxicity of amyloids aggregates is linked to the levels of autophagy in cells. These results suggest that a strong impairment of the immune system in the brain may be the first stop of neurodegenerative processes that are taking place upon the onset of PD.</div></div>","PeriodicalId":8760,"journal":{"name":"Biochimica et biophysica acta. Proteins and proteomics","volume":"1873 2","pages":"Article 141061"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142852091","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}
Lorieth A. Guevara Cuasapud , Pablo J. González , Félix M. Ferroni , Andrea B. Duré , Sergio D. Dalosto , Maria G. Rivas , Carlos D. Brondino
{"title":"Replacement of the essential catalytic aspartate with serine leads to an active form of copper-containing nitrite reductase from the denitrifier Sinorhizobium meliloti 2011","authors":"Lorieth A. Guevara Cuasapud , Pablo J. González , Félix M. Ferroni , Andrea B. Duré , Sergio D. Dalosto , Maria G. Rivas , Carlos D. Brondino","doi":"10.1016/j.bbapap.2024.141062","DOIUrl":"10.1016/j.bbapap.2024.141062","url":null,"abstract":"<div><div>We report the molecular, biochemical and spectroscopic characterization and computational calculations of a variant of the copper-containing nitrite reductase from the rhizobial microorganism <em>S. meliloti</em> (<em>Sm</em>NirK), in which the catalytic aspartate residue (Asp<sub>CAT</sub>) has been replaced with serine (Ser<sub>CAT</sub>, D134S) by site-directed mutagenesis. Like the wild-type enzyme, D134S is a homotrimer with the typical catalytic pocket of two-domain NirK containing two copper centers, one of type 1 (T1) and another of type 2 (T2). The T1 electron transfer center is similar to that of the wild-type enzyme but the electronic and covalent properties of T2 active site are altered by the mutation. As for the wild-type enzyme, the enzymatic activity of D134S is pH-dependent, i.e. it is higher at lower pH values, but the <em>k</em><sub>cat</sub> is an order of magnitude lower. EPR studies showed a decrease in <em>g</em><sub>‖</sub> and an increase in <em>A</em><sub>‖</sub> of D134S relative to wild-type enzyme. This indicates changes in the electronic and covalent properties of T2 upon mutation, which affects the reduction potential of T2 and the T1-T2 reduction potential gap. Taken together, this evidence points to the importance of the ligands of the second coordination sphere of T2 in controlling critical parameters in catalysis. The possibility that Asp<sub>CAT</sub>/Ser<sub>CAT</sub> is the switch that triggers T1 → T2 electron transfer upon T2 nitrite binding and the importance of His<sub>CAT</sub> for the pH-dependent catalytic activity of NirK are discussed.</div></div>","PeriodicalId":8760,"journal":{"name":"Biochimica et biophysica acta. Proteins and proteomics","volume":"1873 2","pages":"Article 141062"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142913782","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}
Puji Rahayu , Doni Dermawan , Florensia Nailufar , Erna Sulistyaningrum , Raymond R. Tjandrawinata
{"title":"Unlocking the wound-healing potential: An integrative in silico proteomics and in vivo analysis of Tacorin, a bioactive protein fraction from Ananas comosus (L.) Merr. Stem","authors":"Puji Rahayu , Doni Dermawan , Florensia Nailufar , Erna Sulistyaningrum , Raymond R. Tjandrawinata","doi":"10.1016/j.bbapap.2024.141060","DOIUrl":"10.1016/j.bbapap.2024.141060","url":null,"abstract":"<div><div>Tacorin, a bioactive protein fraction derived from pineapple stem (<em>Ananas comosus</em>), has emerged as a promising therapeutic agent for wound healing. This study employs an integrated approach, combining <em>in silico</em> proteomics and <em>in vivo</em> investigations, to unravel the molecular mechanisms underlying Tacorin's wound healing properties. In the domain of <em>in silico</em> proteomics, the composition of Tacorin is elucidated through LC/MS-MS protein sequencing, revealing ananain (23.77 kDa) and Jacalin-like lectin (14.99 kDa) as its predominant constituents. Molecular protein-protein docking simulations unveil favorable interactions between Tacorin's components and key regulators of wound healing, including TGF-β, TNF-α, and MMP-2. The calculated free binding energies indicate strong binding affinities between Tacorin proteins and their target receptors. Specifically, ananain demonstrates a binding affinity of −12.2 kcal/mol with TGF-β, suggesting its potential as a potent activator of TGF-β-mediated signaling, while Jacalin-like lectin exhibits the most favorable binding affinity of −8.7 kcal/mol with TNF-α. Subsequent 100 ns molecular dynamics (MD) simulations provide insights into the dynamic behavior and stability of Tacorin-receptor complexes, shedding light on the molecular determinants of Tacorin's therapeutic effects. Complementing the <em>in silico</em> analyses, <em>in vivo</em> studies evaluate Tacorin's efficacy in wound healing using skin and uterine incision models. Tacorin treatment accelerates wound closure and promotes tissue repair in both models, as evidenced by macroscopic observations and histological assessments. Overall, this study provides compelling evidence of Tacorin's therapeutic potential in wound healing and underscores the importance of elucidating its molecular mechanisms for further development and clinical translation.</div></div>","PeriodicalId":8760,"journal":{"name":"Biochimica et biophysica acta. Proteins and proteomics","volume":"1873 1","pages":"Article 141060"},"PeriodicalIF":2.5,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748237","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}
Chukwuemeka S. Adindu , Katie Tombrello , Luke A. Martz , Tonya N. Zeczycki , Holly R. Ellis
{"title":"A distinct co-expressed sulfurtransferase extends the physiological role of mercaptopropionate dioxygenase in Pseudomonas aeruginosa PAO1","authors":"Chukwuemeka S. Adindu , Katie Tombrello , Luke A. Martz , Tonya N. Zeczycki , Holly R. Ellis","doi":"10.1016/j.bbapap.2024.141059","DOIUrl":"10.1016/j.bbapap.2024.141059","url":null,"abstract":"<div><div>Oxidation and assimilation of persulfides in bacteria is often catalyzed by a persulfide dioxygenase and sulfurtransferase in consecutive reactions. Enzymes responsible for the oxidation of persulfides have not been clearly defined in <em>Pseudomonas aeruginosa</em> PAO1. The characterized mercaptopropionate dioxygenase (MDO) in <em>P. aeruginosa</em> PAO1 has been proposed to catalyze the oxidation of 3-mercaptopropionate. However, the physiological role of MDO is uncertain given the expression of a sulfurtransferase (ST) enzyme on the same operon as the thiol dioxygenase. The <em>st</em> gene had a co-occurrence frequency with <em>mdo</em> of 0.94 demonstrating the co-expression and physiological link of the two genes. There are four tandem rhodanese domains in the ST enzyme with two of the domains containing potential catalytic Cys residues (Cys191 and Cys435) capable of forming a persulfide. Only Cys435 was accessible in thiol quantification assays, and results from H/D-X MS analyses further established the accessibility of the domain containing Cys435. Both thiosulfate and mercaptopyruvate served as sulfur donors to the ST enzyme, with Cys435 forming the persulfide intermediate. Kinetic investigations of MDO suggested the enzyme had a broader substrate specificity than previously identified, oxidizing both mercaptopropionate and mercaptopyruvate thiol and persulfide substrates. The results obtained from these investigations provide insight into the overall mechanism and physiological role of the <em>mdo</em> operon in sulfide oxidation and assimilation.</div></div>","PeriodicalId":8760,"journal":{"name":"Biochimica et biophysica acta. Proteins and proteomics","volume":"1873 1","pages":"Article 141059"},"PeriodicalIF":2.5,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142543387","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}
Mengxue Wang , Xinyi Sun , Shijiang Peng , Feifan Wang , Kangli Zhao , Dang Wang
{"title":"Deciphering the cleavage sites of 3C-like protease in Gammacoronaviruses and Deltacoronaviruses","authors":"Mengxue Wang , Xinyi Sun , Shijiang Peng , Feifan Wang , Kangli Zhao , Dang Wang","doi":"10.1016/j.bbapap.2024.141057","DOIUrl":"10.1016/j.bbapap.2024.141057","url":null,"abstract":"<div><div>Coronaviruses replicate by using the 3C-like protease (3CL<sup>pro</sup>) to cleave polyprotein precursors and host proteins. However, current tools for identifying 3CL<sup>pro</sup> cleavage sites are limited, particularly in <em>Gammacoronaviruses</em> (GammaCoV) and <em>Deltacoronaviruses</em> (DeltaCoV). This study aims to fill this gap by identifying 3CL<sup>pro</sup> cleavage sites in these viruses to provide deeper insights into their pathogenic mechanisms. By integrating sequence alignments and structural model comparisons, we developed a position-specific scoring matrix (PSSM) based on self-cleavage motifs, revealing specific preferences for each residue. Utilizing AlphaFold2's predicted alignment error (PAE) and predicted local distance difference test (pLDDT), we found that most cleavage sequences are located in regions with high PAE and low pLDDT values. KEGG pathway analysis showed that potential host protein cleavage targets are mainly concentrated in pathways related to nucleo-cytoplasmic transport and endocytosis. Through <em>in vitro</em> cleavage experiments and mutational analysis, we identified and validated three high-scoring proteins—nucleoporin 58 (NUP58), cell division cycle 73 (CDC73), and signal transducing adaptor molecule 2 (STAM2). These findings suggest that 3CL<sup>pro</sup> not only plays a vital role in viral replication but may also influence host cell functions by cleaving host proteins. This study provides an effective tool for identifying 3CL<sup>pro</sup> cleavage sites, revealing the pathogenic mechanisms of coronaviruses, and offering new insights for developing potential therapeutic targets.</div></div>","PeriodicalId":8760,"journal":{"name":"Biochimica et biophysica acta. Proteins and proteomics","volume":"1873 1","pages":"Article 141057"},"PeriodicalIF":2.5,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142493886","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}