{"title":"ECH 1 attenuates atherosclerosis by reducing macrophage infiltration and improving plaque stability through CD36 degradation.","authors":"Caijun Rao, Haojie Qin, Zhipeng Du","doi":"10.1016/j.abb.2024.110217","DOIUrl":"https://doi.org/10.1016/j.abb.2024.110217","url":null,"abstract":"<p><p>Enoyl coenzyme A hydratase 1 (ECH1) is a secreted protein implicated in numerous metabolic disorders, yet its role in the pathogenesis of atherosclerosis remains unclear. In this study, we found higher serum ECH1 levels in coronary artery disease (CAD) patients and apolipoprotein E (ApoE)<sup>-/-</sup> mice on a western diet for 12 weeks. In vivo, aorta and aortic sinus histological staining revealed that intraperitoneal injection of recombinant ECH1 reduced aortic lesions, inflammation, and macrophage infiltration in ApoE<sup>-/-</sup> mice. In vitro, incubating peritoneal macrophages with recombinant ECH1 protein reduced oxidized low-density lipoprotein uptake and increased macrophage migration. Mechanically, we observed that recombinant ECH1 incubation led to a reduction in the protein levels of scavenger receptor cluster of differentiation 36 (CD36) in primary macrophages through the promotion of CD36 protein degradation. Additionally, we found that chloroquine (CQ), a lysosomal inhibitor, mitigated this pro-degradation effect. Taken together, our findings provide unique evidence that ECH1 can attenuate the severity of atherosclerotic plaques, especially improving the stability of plaques, by decreasing macrophage infiltration. ECH1 demonstrates its protective effect by enhancing the lysosome-dependent degradation of CD36, suggesting its potential as a viable target for the prevention and treatment of atherosclerosis.</p>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":" ","pages":"110217"},"PeriodicalIF":3.8,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142646050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dong Han , Yun-Biao Chen , Kai Zhao , Hong-Zhou Li , Xing-Yu Chen , Guo-Zheng Zhu , Chen Tu , Jia-Wen Gao , Jing-Shen Zhuang , Zhi-Yong Wu , Zhao-Ming Zhong
{"title":"Tanshinone IIA alleviates inflammation-induced skeletal muscle atrophy by regulating mitochondrial dysfunction","authors":"Dong Han , Yun-Biao Chen , Kai Zhao , Hong-Zhou Li , Xing-Yu Chen , Guo-Zheng Zhu , Chen Tu , Jia-Wen Gao , Jing-Shen Zhuang , Zhi-Yong Wu , Zhao-Ming Zhong","doi":"10.1016/j.abb.2024.110215","DOIUrl":"10.1016/j.abb.2024.110215","url":null,"abstract":"<div><div>Skeletal muscle atrophy, characterized by loss of muscle mass and function, is often linked to systemic inflammation. Tanshinone IIA (Tan IIA), a major active constituent of <em>Salvia miltiorrhiza</em>, has anti-inflammatory and antioxidant properties. However, the effect of Tan IIA on inflammation-induced skeletal muscle atrophy remains unclear. Here, a mice model of the inflammatory muscle atrophy was established using lipopolysaccharide (LPS). Tan IIA intervention significantly increased muscle mass and strength, improved muscle fiber size, and maintained the integrity of skeletal muscle mitochondrial morphology in LPS-treated mice. Myotubes derived from myosatellite cells (MUSCs) were exposed to LPS in vitro<em>.</em> Tan IIA treatment inhibited LPS-induced muscle protein degradation and increased myotube diameter. Notably, Tan IIA attenuated LPS-induced inflammatory response and hyperactive mitophagy both in vivo and in vitro. In addition, Tan IIA treatment effectively diminished oxidative stress, inhibited the accumulation of mitochondrial reactive oxygen species (mtROS), and attenuated mitochondrial fission in LPS-treated myotubes. Reducing mtROS production helped to inhibit LPS-induced excessive mitophagy and myotubes atrophy. Together, our results reveal that Tan IIA can protect against inflammation-induced skeletal muscle atrophy by regulating mitochondrial dysfunction, presenting innovative potential therapeutics for skeletal muscle atrophy.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"762 ","pages":"Article 110215"},"PeriodicalIF":3.8,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142638205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yanling Xuan, Jingyi Xu, Hongliang Que, Jianyun Zhu
{"title":"Effects of sulforaphane on prostate cancer stem cells-like properties: In vitro and molecular docking studies.","authors":"Yanling Xuan, Jingyi Xu, Hongliang Que, Jianyun Zhu","doi":"10.1016/j.abb.2024.110216","DOIUrl":"https://doi.org/10.1016/j.abb.2024.110216","url":null,"abstract":"<p><p>The increasing incidence of prostate cancer worldwide has spurred research into novel therapeutics for its treatment and prevention. A critical factor contributing to its incidence and development is the presence of prostate cancer stem cells (PCSCs). Targeting PCSCs has become key in enhancing therapeutic and clinical outcomes of prostate cancer. Sulforaphane (SFN), a compound found in cruciferous vegetables, has shown effective antineoplastic activity in prostate cancer. Yet, its mechanisms of action in PCSCs remains unclear. In the present study, tumorsphere formation assay was used to isolate and enrich PCSCs from PC-3 cells. Our results found that SFN effectively reduced the activity of PCSCs, including the ability of tumorsphere formation, the number of CD133 positive cells, and the expression of PCSCs markers. Moreover, the data showed that SFN inhibited PCSCs through downregulating the activation of Wnt/β-catenin and hedgehog signaling pathways in PCSCs. Furthermore, the verification experiments showed that the activators of Wnt/β-catenin (LiCl) and hedgehog (purmorphamine) attenuated the effects of SFN on PCSCs, including the expression of stem cell markers, cell proliferation and apoptosis. Meanwhile, suppression of β-catenin or Smoothened enhanced the effects of SFN on PCSCs. In addition, molecular docking further indicated that SFN inhibited Wnt/β-catenin and hedgehog pathways by directly targeting β-catenin and Smoothened. Taken together, our results demonstrated that SFN targeted PCSCs through Wnt/β-catenin and hedgehog pathways to inhibit stemness and proliferation and induce apoptosis. Findings from this study could provide new insights into SFN as a dietary supplement or adjunct to chemotherapy.</p>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":" ","pages":"110216"},"PeriodicalIF":3.8,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142643275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jonathan A Semelak, Mariana Gallo, F Luis González Flecha, Solana Di Pino, Thelma A Pertinhez, Ari Zeida, Ivan Gout, Dario A Estrin, Madia Trujillo
{"title":"Mg<sup>2+</sup> binding to Coenzyme A.","authors":"Jonathan A Semelak, Mariana Gallo, F Luis González Flecha, Solana Di Pino, Thelma A Pertinhez, Ari Zeida, Ivan Gout, Dario A Estrin, Madia Trujillo","doi":"10.1016/j.abb.2024.110202","DOIUrl":"https://doi.org/10.1016/j.abb.2024.110202","url":null,"abstract":"<p><p>Magnesium (Mg<sup>2+</sup>), the second most abundant intracellular cation, plays a crucial role in cellular functions. In this study, we investigate the interaction between Mg<sup>2+</sup> and coenzyme A (CoA), a thiol-containing cofactor central to cellular metabolism also involved in protein modifications. Isothermal titration calorimetry revealed a 1:1 binding stoichiometry between Mg<sup>2+</sup> and free CoA under biologically relevant conditions. Association constants of (537 ± 20) M<sup>-1</sup> and (312 ± 7) M<sup>-1</sup> were determined at 25°C and pH 7.2 and 7.8, respectively, suggesting that a significant fraction of CoA is likely bound to Mg<sup>2+</sup> both in the cytosol and in the mitochondrial matrix. Additionally, the process is entropically-driven, and our results support that the origin of the entropy gain is solvent-related. On the other hand, the combination of 1- and 2-dimensional nuclear magnetic resonance spectroscopy with molecular dynamics simulations and unsupervised learning demonstrate a direct coordination between Mg<sup>2+</sup> and the phosphate groups of the 4-phosphopantothenate unit and bound to position 5' of the adenosine ring. Interestingly, the phosphate in position 3' only indirectly contributes to Mg<sup>2+</sup> coordination. Finally, we discuss how the binding of Mg<sup>2+</sup> to CoA perturbates the chemical environment of different CoA atoms, regardless of their apparent proximity to the coordination site, through the modulation of the CoA conformational landscape. This insight holds implications for understanding the impact on both CoA and Mg<sup>2+</sup> functions in physiological and pathological processes.</p>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":" ","pages":"110202"},"PeriodicalIF":3.8,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142613546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Bacterial expression, purification, and characterization of human cytochrome P450 3A4 without N-terminal modifications","authors":"Yudong Sun, Yoichi Osawa, Haoming Zhang","doi":"10.1016/j.abb.2024.110208","DOIUrl":"10.1016/j.abb.2024.110208","url":null,"abstract":"<div><div>In this communication we reported a bacterial system that over-expressed full-length wild-type (WT) human CYP3A4 in <em>Escherichia coli</em> (<em>E. coli</em>) at a level of 495 nmol/L culture. This level of expression was achieved by cloning the cDNA sequence of CYP3A4 WT to a pLW01-P450 vector and co-expressing it with chaperones GroEL/ES in bacterial C41(DE3) cells. Aided with a C-terminal His<sub>5</sub>-tag, the expressed CYP3A4 WT was purified to homogeneity with a specific content of 14.3 ± 2.0 nmole P450/mg protein using a single Ni-Penta agarose column. Like the N-terminal modified form (CYP3A4-NF14), CYP3A4 WT binds substrate testosterone with a typical sigmoidal feature at slightly higher affinity. Functional characterization revealed that CYP3A4 WT exhibited lower testosterone 6β-hydroxylase activities than CYP3A4-NF14 in reconstituted phospholipid systems. In addition, it was found that the 6β-hydroxylase activity of CYP3A4 WT was less dependent on excess cytochrome P450 oxidoreductase (POR), compared with CYP3A4-NF14. These results suggest that the N-terminal membrane anchor of CYP3A4 WT enhances its interactions with POR and marginally increases testosterone binding.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"762 ","pages":"Article 110208"},"PeriodicalIF":3.8,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142613642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrea Moreno , Isabel Quereda-Moraleda , Celia Lozano-Vallhonrat , María Buñuel-Escudero , Sabine Botha , Christopher Kupitz , Stella Lisova , Ray Sierra , Valerio Mariani , Pamela Schleissner , Leland B. Gee , Katerina Dörner , Christina Schmidt , Huijong Han , Marco Kloos , Peter Smyth , Joana Valerio , Joachim Schulz , Raphael de Wijn , Diogo V.M. Melo , Milagros Medina
{"title":"New insights into the function and molecular mechanisms of Ferredoxin-NADP+ reductase from Brucella ovis","authors":"Andrea Moreno , Isabel Quereda-Moraleda , Celia Lozano-Vallhonrat , María Buñuel-Escudero , Sabine Botha , Christopher Kupitz , Stella Lisova , Ray Sierra , Valerio Mariani , Pamela Schleissner , Leland B. Gee , Katerina Dörner , Christina Schmidt , Huijong Han , Marco Kloos , Peter Smyth , Joana Valerio , Joachim Schulz , Raphael de Wijn , Diogo V.M. Melo , Milagros Medina","doi":"10.1016/j.abb.2024.110204","DOIUrl":"10.1016/j.abb.2024.110204","url":null,"abstract":"<div><div>Bacterial ferredoxin(flavodoxin)-NADP<sup>+</sup> reductases (FPR) primarily catalyze the transfer of reducing equivalents from NADPH to ferredoxin (or flavodoxin) to provide low potential reducing equivalents for the oxidoreductive metabolism. In addition, they can be implicated in regulating reactive oxygen species levels. Here we assess the functionality of FPR from <em>B. ovis</em> to understand its potential roles in the bacteria physiology. We prove that this FPR is active with the endogenous [2Fe–2S] Fdx ferredoxin, exhibiting a <em>K</em><sub>M</sub><sup>Fdx</sup> in the low micromolar range. At the molecular level, this study provides with the first structures of an FPR at room temperature obtained by serial femtosecond crystallography, envisaging increase in flexibility at both the adenine nucleotide moiety of FAD and the C-terminal tail. The produced microcrystals are in addition suitable for future mix-and-inject time-resolved studies with the NADP<sup>+</sup>/H coenzyme either at synchrotrons or XFELs. Furthermore, the study also predicts the ability of FPR to simultaneously interact with Fdx and NADP<sup>+</sup>/H.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"762 ","pages":"Article 110204"},"PeriodicalIF":3.8,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142613641","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}
{"title":"High intensity interval training as a therapy: Mitophagy restoration in breast cancer","authors":"Kayvan Khoramipour , Afsaneh Soltany , Pouria Khosravi , Maryam Hossein Rezaei , Elham Madadizadeh , Celia García-Chico , Sergio Maroto-Izquierdo , Karen Khoramipour","doi":"10.1016/j.abb.2024.110213","DOIUrl":"10.1016/j.abb.2024.110213","url":null,"abstract":"<div><div>Recent studies have highlighted the role of mitophagy in tumorigenesis. This study aimed to investigate the effects of high-intensity interval training (HIIT) on mitophagy in tumor tissues of mice with breast cancer. Twenty-eight female BALB/c mice were randomly assigned to four groups: Healthy Control (CO), Cancer (CA), Exercise (EX), and Cancer + Exercise (CA + EX). Mammary tumors were induced in the CA and CA + EX groups via 4T1 cell injections. Upon confirmation of tumor formation, the EX and CA + EX groups underwent 8 weeks (40 sessions) of HIIT, comprising 4–10 intervals of running at 80–100 % of maximum speed. The expression levels of mitophagy-related proteins, including parkin, PTEN-induced putative kinase 1 (PINK1), NIP3-like protein X (NIX), BCL2 interacting protein-3 (BINP3), microtubule-associated protein light chain 3-I (LC3-I), microtubule-associated protein light chain 3-II (LC3-II), AMP-activated protein kinase (AMPK), Unc-51 like autophagy activating kinase-1 (ULK1), and sirtuin-1 (SIRT1), were measured in breast and tumor tissues. Tumor volume relative to body weight was assessed weekly during the eight-week HIIT intervention. Protein expression of parkin, PINK1, NIX, BINP3, LC3-II, LC3-I, AMPK, ULK1, and SIRT1 was reduced in the breast tissue of the CA group, while HIIT restored expression levels across all measured variables (P < 0.01). Additionally, tumor volume relative to body weight was significantly lower in the CA + EX group compared to the CA group from weeks 3–8 (P < 0.01). These findings suggest that breast cancer suppresses mitophagy, yet HIIT effectively reverses this suppression, potentially reducing tumor burden. HIIT may thus represent a promising therapeutic strategy for managing breast cancer.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"762 ","pages":"Article 110213"},"PeriodicalIF":3.8,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142613643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Corrigendum to \"Aldose reductase with quinolone antibiotics interaction: In vitro and in silico approach of its relationship with diabetic complications\" [Arch. Biochem. Biophys. 761 (2024) 110161].","authors":"Cüneyt Türkeş","doi":"10.1016/j.abb.2024.110211","DOIUrl":"https://doi.org/10.1016/j.abb.2024.110211","url":null,"abstract":"","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":" ","pages":"110211"},"PeriodicalIF":3.8,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142613542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiuxiu Ma , Fangling Xu , Koukou Yu , Fan Wang , Quan Li , Weifeng Liang , Bing Liu , Bo Zhang , Jiapeng Zhu , Jiao Li
{"title":"Purification and catalysis of choline dehydrogenase from Escherichia coli","authors":"Xiuxiu Ma , Fangling Xu , Koukou Yu , Fan Wang , Quan Li , Weifeng Liang , Bing Liu , Bo Zhang , Jiapeng Zhu , Jiao Li","doi":"10.1016/j.abb.2024.110212","DOIUrl":"10.1016/j.abb.2024.110212","url":null,"abstract":"<div><div>Choline dehydrogenase (CHDH) is a membrane-bound enzyme belonging to the glucose-methanol-choline (GMC) oxidoreductase superfamily, which is characterized by a crucial FAD-binding domain essential for catalytic function. CHDH catalyzes the oxidation of choline to betaine aldehyde, which is further oxidized to betaine, a vital osmoprotectant and methyl donor for cellular physiology and metabolism. However, the detailed catalytic mechanism of CHDH still remains poorly understood. In our investigation, we gained purity <em>E. coli</em> CHDH samples in DDM (n-dodecyl-β-D-maltoside) and SMA (styrene maleic acid) copolymer respectively and examined their structural composition and catalytic activity separately. Our findings demonstrated the effectiveness of SMA, commonly employed for extracting transmembrane proteins and can preserve the natural bio-membrane environment surrounding the enzyme, in extracting peripheral membrane proteins like CHDH here, which lacks transmembrane helices. CHDH exhibited a trimeric conformation in SMA, whereas it existed as monomers in DDM, as determined by our negative staining analysis. Our experiments also revealed that highly pure <em>E. coli</em> CHDH could only oxidize choline to betaine aldehyde but failed to further oxidize betaine aldehyde to betaine as determined by the biochemical and enzymatic reaction kinetic assays. In addition, the enzyme in SMA displayed greater catalytic activity compared to that in DDM. Furthermore, we confirmed the crucial role of His473, which is hypothesized to be a critical site for substrate binding from our structural comparative analysis between CHDH and its highly homologous choline oxidase, in the catalytic activity of the enzyme through gene mutation. Our work also sheds light on CHDH's contribution to cellular osmotic tolerance through gene knockout. This research enhances our better understanding of CHDH within cellular biochemistry and metabolic pathways.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"762 ","pages":"Article 110212"},"PeriodicalIF":3.8,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142602866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Luis Guevara , Melissa Gouge , Amanda Ohler , S. Gage Hill , Soham Patel , Adam R. Offenbacher
{"title":"Effect of solvent viscosity on the activation barrier of hydrogen tunneling in the lipoxygenase reaction","authors":"Luis Guevara , Melissa Gouge , Amanda Ohler , S. Gage Hill , Soham Patel , Adam R. Offenbacher","doi":"10.1016/j.abb.2023.109740","DOIUrl":"10.1016/j.abb.2023.109740","url":null,"abstract":"<div><p><span><span>Hydrogen tunneling in enzyme reactions<span> has played an important role in linking protein thermal motions to the chemical steps of catalysis. Lipoxygenases<span> (LOXs) have served as model systems for such reactions, showcasing deep hydrogen tunneling mechanisms associated with enzymatic C–H bond cleavage from polyunsaturated fatty acids. Here, we examined the effect of solvent viscosity on the protein thermal motions associated with LOX catalysis using trehalose and glucose as viscogens. Kinetic analysis of the reaction of the paradigm plant orthologue, soybean lipoxygenase (SLO), with </span></span></span>linoleic acid revealed no effect on the first-order rate constants, </span><em>k</em><sub>cat</sub>, or activation energy, <em>E</em><sub>a</sub>. Further studies of SLO active site mutants displaying varying <em>E</em><sub>a</sub>s, which have been used to probe catalytically relevant motions, likewise provided no evidence for viscogen-dependent motions. Kinetic analyses were extended to a representative fungal LOX from <em>M. oryzae, Mo</em>LOX, and a human LOX, 15-LOX-2. While <em>Mo</em>LOX behaved similarly to SLO, we show that viscogens inhibit 15-LOX-2 activity. The latter implicates viscogen sensitive, conformational motions in animal LOX reactions. The data provide insight into the role of water hydration layers in facilitating hydrogen (quantum) tunneling in LOX.</p></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"747 ","pages":"Article 109740"},"PeriodicalIF":3.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10293482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}