Anna S. Tolmacheva, Svetlana E. Soboleva, Evgeny A. Ermakov, Pavel S. Dmitrenok, Georgy A. Nevinsky
{"title":"Oxidoreductase Activity of a Stable Multi-protein Complex from the Sea Cucumber Eupentacta fraudatrix","authors":"Anna S. Tolmacheva, Svetlana E. Soboleva, Evgeny A. Ermakov, Pavel S. Dmitrenok, Georgy A. Nevinsky","doi":"10.1007/s10930-026-10332-w","DOIUrl":"10.1007/s10930-026-10332-w","url":null,"abstract":"<div>\u0000 \u0000 <p>Bioactive compounds, such as peptides, proteins, and protein complexes, including those with antioxidant properties, are abundant in marine organisms. However, the antioxidant properties of protein complexes from sea cucumbers are underexplored. In this study, we show for the first time that a stable multi-protein complex (SMPC) from the sea cucumber <i>E. fraudatrix</i> possesses oxidoreductase activities. The SMPC was obtained by sequential gel-filtration on Sepharose 4B and Sephacryl S-1000 sorbent. Using a spectrophotometric method and an in situ activity assay, showed that the SMPC catalyzed hydrogen peroxide decomposition (specific activity 85.1 ± 4.4 mM H<sub>2</sub>O<sub>2</sub>/min/mg) as well as 3,3′-diaminobenzidine (DAB) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) oxidation both in the presence (84.2 ± 3.1 mM/min/mg; 285.1 ± 11.2 mM/min/mg) or absence (61.4 ± 1.8 mM/min/mg; 178.3 ± 5.0 mM/min/mg) of hydrogen peroxide respectively. The data obtained showed that the SMPC from <i>E. fraudatrix</i> possesses oxidoreductase activities and can be involved in reactive oxygen species level regulation. This study highlighted the need for further research on SMPCs and their potential role in marine organisms.</p>\u0000 </div>","PeriodicalId":793,"journal":{"name":"The Protein Journal","volume":"45 4","pages":"511 - 520"},"PeriodicalIF":1.9,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147793672","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}
Yasin Onay, Gülşah Çelik Gül, Figen Kurtuluş, Mine Nazan Kerimak-Öner, Tuna Demirci, Mustafa Oğuzhan Kaya
{"title":"In Vitro Effects of Cerium Vanadate (CeVO4) Derivatives on Paraoxonase (PON1) Enzyme","authors":"Yasin Onay, Gülşah Çelik Gül, Figen Kurtuluş, Mine Nazan Kerimak-Öner, Tuna Demirci, Mustafa Oğuzhan Kaya","doi":"10.1007/s10930-026-10330-y","DOIUrl":"10.1007/s10930-026-10330-y","url":null,"abstract":"<div>\u0000 \u0000 <p>Cerium vanadate (CeVO<sub>4</sub>)–based materials have attracted attention due to their diverse physicochemical and biological properties; however, their interactions with detoxification-related enzymes remain insufficiently characterized. This study evaluated the <i>in vitro</i> effects of alkaline earth metal–doped CeVO<sub>4</sub> derivatives (Be, Mg, Ca, Sr, and Ba) on human serum paraoxonase-1 (PON1) paraoxonase activity. PON1 was purified from human serum by hydrophobic interaction chromatography (Sepharose 4B–L-tyrosine–1-naphthylamine), and enzymatic activity was measured spectrophotometrically using paraoxon as the substrate. Inhibitory effects were assessed across multiple concentrations, and IC<sub>50</sub> values were determined from concentration–response curves. All derivatives exhibited concentration-dependent inhibition of PON1 activity, with IC<sub>50</sub> values ranging from 117 to 213 µM. Mg- and Ba-doped CeVO<sub>4</sub> derivatives demonstrated the strongest inhibition at higher doping ratios, whereas Ca-doped derivatives showed reduced inhibitory potency with increasing substitution levels. These findings indicate that dopant identity and concentration significantly influence the interaction between CeVO<sub>4</sub> derivatives and PON1. The study provides insight into metal oxide–enzyme interactions and highlights the importance of dopant-dependent effects in evaluating the biological and potential toxicological behavior of engineered vanadate-based materials.</p>\u0000 </div>","PeriodicalId":793,"journal":{"name":"The Protein Journal","volume":"45 3","pages":"479 - 486"},"PeriodicalIF":1.4,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147793730","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":"Proteins for Polyphenol Encapsulation, Functional Food Production, and Breast Cancer Incidence Reduction: Impact of pH Conditions, BSA Particle Size, and Curcumin Concentration","authors":"Nassim Salem Adrar, Khodir Madani, Sabah Adrar","doi":"10.1007/s10930-026-10331-x","DOIUrl":"10.1007/s10930-026-10331-x","url":null,"abstract":"<div>\u0000 \u0000 <p>Some proteins can be used as carriers for certain polyphenols (such as curcumin) to address the issue of their low bioavailability and to develop novel functional foods. As a result, one of the purposes of this review is to provide a brief overview of polyphenol carrier proteins. Bovine serum albumin (BSA), in particular, has the potential to become an ideal carrier material for curcumin encapsulation. Thus, for the possible use of curcumin-loaded BSA particles to reduce breast cancer incidence, an assessment of the impact of BSA particle size and curcumin concentration at pH 7 on curcumin encapsulation efficiency using BSA represents a valuable contribution to the BSA’s use as a delivery system for curcumin. This forms the main goal of this review. Hydrophobic interactions should play a relevant role in BSA-curcumin binding process such that, the main binding site on the BSA molecules for the curcumin molecules should be located inside a hydrophobic binding pocket of the BSA subdomain IIA near Trp<sub>213</sub>. On the other hand, when account is taken only of the impact of pH conditions on the BSA particle physicochemical characteristics, the largest size of BSA particles should correspond to BSA isoelectric point, and the larger the size of BSA particles, the higher the curcumin encapsulation efficiency. In addition to BSA particle size, curcumin concentration has a strong influence on the efficiency of its encapsulation. However, BSA particle size and curcumin-to-BSA ratio should be optimized for the possible use of curcumin-loaded BSA particles to reduce breast cancer incidence.</p>\u0000 </div>","PeriodicalId":793,"journal":{"name":"The Protein Journal","volume":"45 3","pages":"441 - 460"},"PeriodicalIF":1.4,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147793717","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":"Design, Preparation and Activity Evaluation of Long-Acting Insulin Analogues","authors":"Shuchen Pei, Jihong Luo, Shaoyu Cai, Kang Luo, Tianbing Guan, Shan Guan","doi":"10.1007/s10930-026-10329-5","DOIUrl":"10.1007/s10930-026-10329-5","url":null,"abstract":"<div><p>In this study, three types of fatty acid side chains were selected to conjugate with different insulin analogue precursors, leading to the design and synthesis of 11 novel insulin analogues. We selected three modifiers to modify the precursor of the insulin analogue. Liquid chromatography-mass spectrometry analysis confirmed that the actual molecular weight of the samples was consistent with the theoretical value. After confirming the structural integrity of the samples, their biological activities were evaluated to verify the necessity and functionality of the modifications. A preliminary assessment was made of the biological activities of all compounds on the HEK293/Luc/INSR cell line, successfully identifying candidate analogue <b>5</b>. Further animal experiments were conducted on analogue <b>5</b>. Through analysis of the body weight, blood drug concentration and AUC of diabetic rats, analogue <b>5</b> exhibited good hypoglycemic activity, effectively prolonging the drug action time and having an ideal application prospect.</p></div>","PeriodicalId":793,"journal":{"name":"The Protein Journal","volume":"45 2","pages":"422 - 430"},"PeriodicalIF":1.4,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147730973","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":"Comprehensive Characterization of Polyphenols from Salvia chudaei: HPLC–PDA Profiling, in vitro Biological Activities, and in silico Enzyme Interactions","authors":"Chahrazad Nemer, Roukia Hammoudi, Amal Bendahou, Chawki Bensouici, Duygu misirli, Mahfuz Elmastas, Mahfoud Hadj Mahhamed, Abir Benaissa, Abderrhmane Bouafia, Salah Eddine Laouini","doi":"10.1007/s10930-026-10328-6","DOIUrl":"10.1007/s10930-026-10328-6","url":null,"abstract":"<div><p>Growing interest in medicinal plants has highlighted the need to examine lesser-known species. In this context, the work offers an in-depth analysis of the ethyl acetate extract (EtAc) obtained from the aerial portions of <i>Salvia chudaei</i>, emphasizing its phytochemical composition and biological potential. HPLC–PDA analysis identified eight phenolic compounds, including five phenolic acids (chlorogenic, ferulic, caffeic, gallic, and chicoric acids) and three flavonoids (naringenin, quercetin, and apigenin-7-O-glucoside). The EtAc exhibited high total phenolic (20.32 ± 1.03 mg GAE/g) and flavonoid (20.40 ± 0.12 mg RE/g) contents, consistent with strong antioxidant activity, as evidenced by a low DPPH IC<sub>50</sub> value (6.4 ± 0.10 µg/mL), comparable to ascorbic acid, and a high total antioxidant capacity measured by the phosphomolybdenum assay (2.42 ± 0.09 mg AAE/g extract).Additionally, the EtAc showed notable insecticidal activity against <i>Parlatoria blanchardi</i> (LD<sub>50</sub> = 0.24 ± 0.003 mg/mL) and moderate inhibitory effects on α-amylase (αA) (IC<sub>50</sub> = 0.92 ± 0.15 mg/mL) and acetylcholinesterase (AChE) (IC<sub>50</sub> = 1.44 ± 0.09 mg/mL),as defined by IC<sub>50</sub> values when compared with standard inhibitors. Molecular docking simulations revealed that chicoric acid, naringenin, and quercetin formed stable complexes within the active sites of αA and AChE, stabilized by hydrogen bonding and hydrophobic interactions. Quercetin showed the strongest affinity toward both enzymes. Collectively, the results demonstrate that <i>S. chudaei</i> is a promising natural source of multifunctional bioactive polyphenols with antioxidant, neuroprotective, antidiabetic, and insecticidal properties, supporting its potential in pharmaceutical and agricultural applications.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":793,"journal":{"name":"The Protein Journal","volume":"45 2","pages":"349 - 372"},"PeriodicalIF":1.4,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147719162","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}
Guilherme Feijó de Sousa, Chrystian Nunes Gonçalves, Danillo de Oliveira Della Senta, Camila Garcia de Souza, Alice Calderipe de Lima, João Carlos Rodrigues, Maureen Legendre, David M. Markovitz, Luciano da Silva Pinto
{"title":"Comparative Analysis of Banana Lectins rBanLec-Like and H84T-BanLec: An In Silico and In Vitro Approach","authors":"Guilherme Feijó de Sousa, Chrystian Nunes Gonçalves, Danillo de Oliveira Della Senta, Camila Garcia de Souza, Alice Calderipe de Lima, João Carlos Rodrigues, Maureen Legendre, David M. Markovitz, Luciano da Silva Pinto","doi":"10.1007/s10930-026-10326-8","DOIUrl":"10.1007/s10930-026-10326-8","url":null,"abstract":"<div>\u0000 \u0000 <p>In this study, we conducted structural and comparative analyses of two recombinant banana lectins, rBanLec-like and H84T-BanLec, using both in silico and in vitro approaches. Sequence alignment showed 91.5% identity between the lectins, with differences in 12 amino acids. Structural modeling and secondary structure analysis indicated a high degree of structural similarity, with a root mean square deviation (RMSD) of 0.382 Å, suggesting that the sequence modifications did not lead to significant structural changes. Molecular docking experiments demonstrated a strong affinity of both lectins for mannose, with rBanLec-like exhibiting a lower binding free energy (− 6.6 kcal/mol) compared to H84T-BanLec (− 4.5 kcal/mol). Molecular dynamics simulations confirmed the stability of both proteins, although rBanLec-like displayed greater conformational flexibility. Expression in <i>Escherichia coli</i> showed successful production of both lectins, but rBanLec-like was detected in both soluble and insoluble fractions, whereas H84T-BanLec was exclusively obtained in the soluble fraction. Both lectins significantly inhibited the growth of colorectal adenocarcinoma cells by 62.6% and 76%, respectively. These findings contribute to the structural and functional understanding of banana lectins, highlighting their potential for biotechnological and therapeutic applications.</p>\u0000 </div>","PeriodicalId":793,"journal":{"name":"The Protein Journal","volume":"45 2","pages":"318 - 331"},"PeriodicalIF":1.4,"publicationDate":"2026-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10930-026-10326-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147489211","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}
I. Sh. Goyibnazarov, S. S. Yarmatov, B. J. Kholturayev, Kh. O. Eshchanov, I. B. Sapaev, Sh. A. Yuldoshov, A. A. Sarymsakov, Kh. S. Toshov
{"title":"Physico-Chemical Properties of Silk Sericin Extracted by Hydrothermal Treatment","authors":"I. Sh. Goyibnazarov, S. S. Yarmatov, B. J. Kholturayev, Kh. O. Eshchanov, I. B. Sapaev, Sh. A. Yuldoshov, A. A. Sarymsakov, Kh. S. Toshov","doi":"10.1007/s10930-026-10323-x","DOIUrl":"10.1007/s10930-026-10323-x","url":null,"abstract":"<p>In this work, studies were conducted to achieve the complete extraction of sericin from natural silk cocoons at temperatures of 100 °C and 110 °C for durations ranging 2–24 h without the use of chemical reagents. As a result, sericin samples with molecular weight changing 20–240 kDa were obtained. During the thermal and sublimation drying of the isolated sericin samples, changes in their solubility were observed. Structural changes in the thermally dried sericin samples were analyzed using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. XRD analysis revealed diffraction peaks at 18.9° and 20.7°, indicating the presence of crystalline structure, whereas the samples dried by sublimation exhibited a completely amorphous structure. FTIR spectroscopy showed band broadening in the regions of 3000–3500 cm<sup>− 1</sup> and 1500–1600 cm<sup>− 1</sup> in the thermally dried samples, which was attributed to extensive hydrogen-bond formation compared to the samples dried by sublimation. Rheological analysis further demonstrated that the loss modulus exceeded the storage modulus for sericin sample. The results demonstrate that extract sericin under high temperature without chemical reagent enables the efficient isolation of sericin with different molecular weight, while the drying method strongly influences its structural, solubility, and rheological properties.</p>","PeriodicalId":793,"journal":{"name":"The Protein Journal","volume":"45 2","pages":"409 - 421"},"PeriodicalIF":1.4,"publicationDate":"2026-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147373815","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}
Felipe Neri Melo López, Lina Angélica Zermeño Cervantes, María Guadalupe González Alonso, Claudia Vianney Yañez Ñeco, Ruth Noemí Aguila Ramírez, César Salvador Cardona Félix
{"title":"Biochemical Characterization of the Staphylococcal Endolysin MV-L with Enhanced Activity Under Optimized Conditions and Effective Removal of MRSA from Surfaces and Biofilms","authors":"Felipe Neri Melo López, Lina Angélica Zermeño Cervantes, María Guadalupe González Alonso, Claudia Vianney Yañez Ñeco, Ruth Noemí Aguila Ramírez, César Salvador Cardona Félix","doi":"10.1007/s10930-026-10325-9","DOIUrl":"10.1007/s10930-026-10325-9","url":null,"abstract":"<div><p>Methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) remains a major cause of difficult-to-treat infections, largely due to its multidrug resistance and capacity to form persistent biofilms on medical and industrial surfaces. Bacteriophage-derived endolysins have emerged as promising antibacterial agents, but many still require detailed biochemical characterization to support their potential applications. The present study describes the staphylococcal endolysin MV-L expression, purification, and functional analyses, evaluating its ability to control MRSA on surfaces and in biofilms. MV-L was recombinantly produced in <i>Escherichia coli</i>, purified by nickel affinity chromatography; its lytic activity against exponentially growing MRSA was assessed under different physicochemical conditions. Enzyme exhibited optimal activity in slightly alkaline conditions and moderate temperatures; its performance was strongly influenced by ionic strength and divalent cations. Under optimized conditions, MV-L showed markedly increased lytic efficiency and retained activity at low protein concentrations. Beyond planktonic cells, MV-L significantly reduced MRSA loads on glass and stainless steel and disrupted pre-formed biofilms on polystyrene. These findings highlight how buffer composition and ion availability critically modulate MV-L activity and support the concept that tailored endolysins can be integrated as complementary strategies for MRSA control, particularly in scenarios where conventional disinfectants and antibiotics are limited by resistance or poor efficacy against biofilms.</p></div>","PeriodicalId":793,"journal":{"name":"The Protein Journal","volume":"45 2","pages":"373 - 383"},"PeriodicalIF":1.4,"publicationDate":"2026-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147373809","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":"Effects of Arginine on Hierarchical Protein Aggregation","authors":"Suguru Nishinami, Yoshiki Kihara, Teruo Akuta, Kentaro Shiraki, Tsutomu Arakawa","doi":"10.1007/s10930-026-10324-w","DOIUrl":"10.1007/s10930-026-10324-w","url":null,"abstract":"<div><p>Arginine is widely used in protein formulations to suppress protein aggregation and prolong the lifetime of the native, functional state which undergoes different stresses during storage, shipping and handling. However, arginine’s differential effects on protein aggregation pathways remain unclear. Here, we investigated the effects of arginine on heat- and acid-induced aggregation of immunoglobulin G and heat-induced aggregation of several model proteins. Arginine suppressed the formation of insoluble aggregates but had limited impact on monomer recovery, particularly on immunoglobulin G. Instead, arginine promoted the formation of soluble aggregates, suggesting a possibility that unfolded proteins possess heterogeneous surface properties, leading to formation of soluble and insoluble aggregates that are modulated by arginine. To explain these kinetic behaviors, we propose a hierarchical aggregation model, in which arginine preferentially modulates weaker intermolecular interactions to inhibit the growth of the soluble aggregates into large insoluble aggregates. Moreover, soluble aggregates were observed in a range of proteins with varying isoelectric points and molecular weights. These results highlight a previously unrecognized aspect of soluble protein aggregation. Understanding the pathway and mechanism of soluble aggregate formation may shed light into physiologically-relevant soluble assemblies, e.g., Alzheimer’s disease-associated oligomers and microtubule-derived double rings in contrast to the soluble amorphous aggregates under current study.</p></div>","PeriodicalId":793,"journal":{"name":"The Protein Journal","volume":"45 2","pages":"229 - 244"},"PeriodicalIF":1.4,"publicationDate":"2026-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146260570","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":"Structure-Based Drug Design Targeting the Substrate-Binding Pocket of MexB","authors":"Praveena Nanjan","doi":"10.1007/s10930-026-10321-z","DOIUrl":"10.1007/s10930-026-10321-z","url":null,"abstract":"<div><p>The multidrug-resistant (MDR) phenotype of <i>Pseudomonas aeruginosa</i> poses a significant clinical challenge and frequently causes severe and potentially lethal infections. The activity of efflux proteins, which are membrane transporters that use the electrochemical gradient across the bacterial membrane to extrude antimicrobials and reduce their intracellular concentrations, is a significant factor in this resistance. One of the most well-known mechanisms of multidrug resistance in <i>Pseudomonas aeruginosa</i> is the Resistance–Nodulation-Division (RND) efflux pump system. MexB, the inner membrane transporter, is essential for substrate recognition and drug binding in the well-characterised MexAB–OprM complex. A variety of antibiotics, such as Macrolides, Fluoroquinolones, Tetracyclines, Sulfonamides, β-Lactams, Trimethoprim, Novobiocin, and Chloramphenicol, are resistant to this pump. The overexpression of this tripartite efflux system, which consists of the outer membrane channel OprM, the membrane fusion protein MexA, and the inner membrane transporter MexB, is regulated by genes including <i>mexR</i>,<i> nalC</i>, and <i>nalD</i>. MexB involvement in drug resistance makes it a prime target for the development of efflux pump inhibitors (EPIs). Antibiotics and EPIs together have the potential to restore antibacterial activity by enhancing intracellular drug retention. However, restricted access to complex structural and computational tools required for logical drug design has hindered the development of EPI. This study examines novel EPIs that target <i>P. aeruginosa</i> RND-type efflux systems and discusses recent structural discoveries regarding the MexB transporter.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":793,"journal":{"name":"The Protein Journal","volume":"45 1","pages":"100 - 114"},"PeriodicalIF":1.4,"publicationDate":"2026-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146222694","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}