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In this work, we developed a smart drug delivery system composed of poly (ethylene glycol)-block-poly (ε-caprolactone) (PEG-PCL)-based polymersomes (Ps) loaded with doxorubicin (DOX) and vemurafenib (VEM). To enhance targeted delivery to malignant melanoma cells, these drug-loaded nanovesicles were conjugated to the oxalate transferrin variant (oxalate Tf) and incorporated into three-dimensional chitosan hydrogels. This innovative approach represents the first application of oxalate Tf for the precision delivery of drug-loaded polymersomes within a semi-solid dosage form based on chitosan hydrogels. These resulting semi-solids exhibited a sustained release profile for both encapsulated drugs. To evaluate their potency, we compared the cytotoxicity of native Tf-Ps with oxalate Tf-Ps. Notably, the oxalate Tf-Ps demonstrated a 3-fold decrease in cell viability against melanoma cells compared to normal cells and were 1.6-fold more potent than native Tf-Ps, indicating the greater potency of this nanoformulation. These findings suggest that dual-drug delivery using an oxalate-Tf-targeting ligand significantly enhances the drug delivery efficiency of Tf-conjugated nanovesicles and offers a promising strategy to overcome the challenge of multidrug resistance in melanoma therapy.

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The cornea is a fundamental ocular tissue for the sense of sight. Thanks to it, the refraction of two-thirds of light manages to participate in the visual process and protect against mechanical damage. Because it is transparent, avascular, and innervated, the cornea comprises five main layers: Epithelium, Bowman's layer, stroma, Descemet's membrane, and endothelium. Each layer plays a key role in the functionality and maintenance of ocular tissue, providing unique ultrastructural and biomechanical properties. Bullous Keratopathy (BK) is an endothelial dysfunction that leads to corneal edema, loss of visual acuity, epithelial blisters, and severe pain, among other symptoms. The corneal layers are subject to changes in their biophysical properties promoted by Keratopathy. In this context, the Atomic Force Microscopy (AFM) technique in air was used to investigate the anterior epithelial surface and the posterior endothelial surface, healthy and with BK, using a triangular silicone tip with a nominal spring constant of 0.4 N/m. Six human corneas (n = 6) samples were used for each analyzed group. Roughness data, calculated by third-order polynomial adjustment, adhesion, and Young's modulus, were obtained to serve as a comparison and identification of morphological and biomechanical changes possibly associated with the pathology, such as craters and in the epithelial layer and exposure of a fibrotic layer due to loss of the endothelial cell wall. Endothelial cell membrane area and volume data were calculated, obtaining a relevant comparison between the control and patient. Such results may provide new data on the physical properties of the ocular tissue to understand the physiology of the cornea when it has pathology.

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Multidrug-resistant Cryptococcus neoformans is an encapsulated yeast causing a high mortality rate in immunocompromised patients. Recently, the synthetic peptide Mo-CBP3-PepII emerged as a potent anticryptococcal molecule with an MIC50 at low concentration. Here, the mechanisms of action of Mo-CBP3-PepII were deeply analyzed to provide new information about how it led C. neoformans cells to death. Light and fluorescence microscopies, analysis of enzymatic activities, and proteomic analysis were employed to understand the effect of Mo-CBP3-PepII on C. neoformans cells. Light and fluorescence microscopies revealed Mo-CBP3-PepII induced the accumulation of anion superoxide and hydrogen peroxide in C. neoformans cells, in addition to a reduction in the activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT) in the cells treated with Mo-CBP3-PepII. In the presence of ascorbic acid (AsA), no reactive oxygen species (ROS) were detected, and Mo-CBP3-PepII lost the inhibitory activity against C. neoformans. However, Mo-CBP3-PepII inhibited the activity of lactate dehydrogenase (LDH) ergosterol biosynthesis and induced the decoupling of cytochrome c (Cyt c) from the mitochondrial membrane. Proteomic analysis revealed a reduction in the abundance of proteins related to energetic metabolism, DNA and RNA metabolism, pathogenicity, protein metabolism, cytoskeleton, and cell wall organization and division. Our findings indicated that Mo-CBP3-PepII might have multiple mechanisms of action against C. neoformans cells, mitigating the development of resistance and thus being a potent molecule to be employed in the production of new drugs against C. neoformans infections.

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The development of bioactivity in bioinert metallic alloys is a field of interest aiming to improve some aspects of these materials for implant applications. New Co63 Cr28 W9-x Tax alloys with different Ta concentrations (x = 0, 2, 4, 6, and 9% w/w) were synthesized in the work reported here. The alloys were characterized by x-ray diffraction, volumetric density, Vickers microhardness, atomic force microscopy, scanning electron microscopy (SEM), and energy-dispersion x-ray spectroscopy (EDS). Bioactivity properties were evaluated by in vitro tests with simulated body fluid (SBF). In vivo assays were performed to assess biocompatibility. The influence of surface thermochemical treatment and Ta insertion on the bioactive properties of the alloys was investigated. The results showed that the alloy structure comprises εCo and αCo phases, with cobalt as a matrix with Cr, W, and Ta as a solid solution. TaCo2 phase is observed in the alloys with 4, 6, and 9% w/w of Ta, and its amount increase as Ta concentration increases. Volumetric density is reduced (from 8.78 ± 0.06 to 8.56 ± 0.09 g/cm3 ) as Ta concentration increases (from 0% to 9% w/w) mainly due to the lower density of the tantalum compared to the tungsten metal. On the other hand, the TaCo2 phase contributes to the increase of Vickers's hardness by ~17.6% for the alloy with 9% Ta (394.7 ± 8.1 HV) compared with Co63 Cr28 W9 (336 ± 5 HV). The topographic analysis showed increased roughness and adhesion due to the nucleation of Ta1.1 O1.05 and Ca2 Ta2 O7 crystals after surface thermochemical treatment. The roughness and adhesion increase from 16.9 ± 0.6 nm and 8.3 ± 1.8 nN (untreated surface) to 255.7 ± 17.7 nm and 24.1 ± 12.6 nN (treated surface), respectively, for the Co63 Cr28 Ta9 alloy. These results suggest that thermochemical treatment provides surface conditions favorable to hydroxyapatite (HA) nucleation. The SEM and EDS data showed the nucleation of spongy structures, consistent with HA, composed mainly of Ca and P, indicating that oxides tantalum promoted a bioactive response on the sample's surface. The biological assay corroborated the alloy's safety and applicability, highlighting its potential in biomedical application since no harmful effects were observed.

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Cryptococcus neoformans is the pathogen responsible for cryptococcal pneumonia and meningitis, mainly affecting patients with suppressed immune systems. We have previously revealed the mechanism of anticryptococcal action of synthetic antimicrobial peptides (SAMPs). In this study, computational and experimental analyses provide new insights into the mechanisms of action of SAMPs. Computational analysis revealed that peptides interacted with the PHO36 membrane receptor of C. neoformans. Additionally, ROS (reactive oxygen species) overproduction, the enzymes of ROS metabolism, interference in the ergosterol biosynthesis pathway, and decoupling of cytochrome c mitochondrial membrane were evaluated. Three of four peptides were able to interact with the PHO36 receptor, altering its function and leading to ROS overproduction. SAMPs-treated C. neoformans cells showed a decrease in scavenger enzyme activity, supporting ROS accumulation. In the presence of ascorbic acid, an antioxidant agent, SAMPs did not induce ROS accumulation in C. neoformans cells. Interestingly, two SAMPs maintained inhibitory activity and membrane pore formation in C. neoformans cells by a ROS-independent mechanism. Yet, the ergosterol biosynthesis and lactate dehydrogenase activity were affected by SAMPs. In addition, we noticed decoupling of Cyt c from the mitochondria, which led to apoptosis events in the cryptococcal cells. The results presented herein suggest multiple mechanisms imposed by SAMPs against C. neoformans interfering in the development of resistance, thus revealing the potential of SAMPs in treating infections caused by C. neoformans.

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Cryptococcus neoformans is a human-pathogenic yeast responsible for pneumonia and meningitis, mainly in patients immunocompromised. Infections caused by C. neoformans are a global health concern. Synthetic antimicrobial peptides (SAMPs) have emerged as alternative molecules to cope with fungal infections, including C. neoformans. Here, eight SAMPs were tested regarding their antifungal potential against C. neoformans and had their mechanisms of action elucidated by fluorescence and scanning electron microscopies. Five SAMPs showed an inhibitory effect (MIC50) on C. neoformans growth at low concentrations. Fluorescence microscope (FM) revealed that SAMPs induced 6-kDa pores in the C. neoformans membrane. Inhibitory assays in the presence of ergosterol revealed that some peptides lost their activity, suggesting interaction with it. Furthermore, FM analysis revealed that SAMPs induced caspase 3/7-mediated apoptosis and DNA degradation in C. neoformans cells. Scanning Electron Microscopy (SEM) analysis revealed that peptides induced many morphological alterations such as cell membrane, wall damage, and loss of internal content on C. neoformans cells. Our results strongly suggest synthetic peptides are potential alternative molecules to control C. neoformans growth and treat the cryptococcal infection.

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Several diseases are characterized by changes in the mechanical properties of erythrocytes. Hemolytic anemias are an example of these diseases. Among the hemolytic anemias, Sickle Cell Disease and Thalassemia are the most common, characterized by alterations in the structure of their hemoglobin. Sickle cell disease has a pathological origin in synthesizing abnormal hemoglobin, HbS. In contrast, thalassemia results in extinction or decreased synthesis of α and ß hemoglobin chains. This work presents a detailed study of biophysical and ultrastructural early erythrocytes membrane alterations at the nanoscale using Atomic Force Microscopy (AFM). Cells from individuals with sickle cell anemia and thalassemia mutations were studied. The analysis methodology in the AFM was given by blood smear and exposure of the inner membrane for ghost analysis. A robust statistic was used with 65,536 force curves for each map, ten cells of each type, with three individuals for each sample group. The results showed significant differences in cell rigidity, adhesion, volume, and roughness at early morphological alterations, bringing new perspectives for understanding pathogenesis. The sickle cell trait (HbAS) results stand out. Significant alterations were observed in the membrane properties, bringing new perspectives for the knowledge of this mutation. This work presents ultrastructural and biomechanical signatures of sickle cell anemia and thalassemia genotypes, which may help determine a more accurate biophysical description and clinical prognosis for these diseases.

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The ongoing outbreak of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) started in late 2019 and spread across the world, infecting millions of people, with over 3.3 million deaths worldwide. To fight back the virus, it is necessary to understand how the main structures work, especially those responsible for the virus infectivity pathogenicity. Here, using the most advanced atomic force microscopy techniques, SARS-CoV-2 viral particles were analyzed, with a special focus on their ultrastructure, adsorption conformation, and nanomechanical behavior. The results uncovered the aspects of the organization and the spatial distribution of the proteins on the surface of the viral particles. It also showed the compliant behavior of the membrane and ability to recover from mechanical injuries. At least three layers composing the membrane and their thickness were measured, protecting the virus from external stress. This study provides new insight into the ultrastructure of SARS-CoV-2 particles at the nanoscale, offering new prospects that could be employed for mapping viral surfaces. The understanding of the viruses' capacity to survive mechanical disruptions at any level and their ability to recover from such injuries can shed a light on the structure-function relationship and help us to find targets for drug action, especially for this virus that, to this day, has no course of treatment approved.

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Resistant nematodes are not affected by the most common drugs commercially available. In the search for new anthelmintics, peptides have been investigated. Here, a linear synthetic peptide named RcAlb-PepIII bioinspired from the antimicrobial protein Rc-2S-Alb was designed, synthesized, and tested against barber pole worm Haemonchus contortus. The physicochemical properties of the peptide, the 3D structure model, the egg hatch inhibition, and larval development inhibition of H. contortus were carried out. Additionally, the ultrastructure of the nematode after treatment with the peptide was evaluated by atomic force microscopy. The RcAlb-PepIII inhibited the larval development of H. contortus with an EC50 of 90 µM and did not affect egg hatch. Atomic force microscopy reveals the high affinity of RcAlb-PepIII with the cuticle of H. contortus in the L2 stage. It also shows the deposition of RcAlb-PepIII onto the surface of the cuticle, forming a structure similar to a film that reduces the roughness and mean square roughness (Rq) of it. In conclusion, the bioinspired RcAlb-PepIII has the potential to be used as a new anthelmintic compound to control gastrointestinal nematode parasites.

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The resistance of Haemonchus contortus to synthetic anthelmintics is of increasing concern; and different strategies are being evaluated to improve parasite control. The present study investigated the in vitro effects of combinations of synthetic compounds and monoterpenes. Additionally, the chemical association of the best combinations and their impact on the ultrastructural and biophysical properties of H. contortus eggs was evaluated. We assessed the efficacy of the monoterpenes, carvacrol, thymol, r-carvone, s-carvone, citral, and p-cymene and the anthelmintics, albendazole and levamisole using the egg hatch test (EHT) and the larval migration inhibition test (LMIT), respectively. The minimum effective concentrations of the monoterpenes, according to the EHT (efficacy ranging from 4.4%-11.8%) and LMIT (efficacy ranging from 5.6%-7.4%), were used in combination with different concentrations of synthetic compounds, and the IC50 and synergism rate (SR) were calculated. Fourier-transform infrared spectroscopy (FTIR) was used to analyze the chemical association between the best combinations as revealed by the in vitro tests (albendazole and levamisole with r-carvone or s-carvone). Atomic force microscopy (AFM) was used to assess the ultrastructural and biophysical properties of H. contortus eggs treated with the albendazole and r-carvone combination. Among the monoterpenes, the highest efficacies were exhibited by carvacrol (IC50 = 185.9 µg/mL) and thymol (IC50 = 187.0 µg/mL), according to the EHT, and s-carvone and carvacrol (IC50 = 1526.0 and 1785.3 µg/mL, respectively), according to the LMIT. According to the EHT, albendazole showed a slight statistically significant synergism in combination with r-carvone (SR = 3.8) and s-carvone (SR = 3.0). According to the LMIT, among the monoterpenes, r-carvone (SR = 1.7) and s-carvone (SR = 1.7) showed an increase in efficacy with levamisole; however, this was not statistically significant. The FTIR spectra of albendazole and levamisole, in association with r-carvone and s-carvone, indicated the presence of chemical interactions between the synthetic and natural molecules, contributing to the possible synergistic effects of these associations. Eggs treated with albendazole and r-carvone showed an increase in roughness and a decrease in height, suggesting that the treatment induced damage to the egg surface and an overflow of its internal contents. Overall, the combination of albendazole with r-carvone and s-carvone was efficacious against H. contortus, demonstrating a chemical association between the compounds; the significant changes in the egg ultrastructure justify this efficacy.

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Multi-wall lipid-core nanocapsule (MLNC) functionalized with captopril and nanoencapsulating furosemide within the core was developed as a liquid formulation for oral administration. The nanocapsules had mean particle size below 200 nm, showing unimodal and narrow size distributions with moderate dispersity (laser diffraction and dynamic light scattering). Zeta potential was inverted from -14.3 mV [LNC-Fur(0,5)] to +18.3 mV after chitosan coating. Transmission electron microscopy and atomic force microscopy showed spherical structures corroborating the nanometric diameter of the nanocapsules. Regarding the systolic pressure, on the first day, the formulations showed antihypertensive effect and a longer effect than the respective drug solutions. When both drugs were associated, the anti-hypertensive effect was prolonged. On the fifth day, a time effect reduction was observed for all treatments, except for the nanocapsule formulation containing both drugs [Capt(0.5)-Zn(25)-MLNC-Fur(0.45)]. For diastolic pressure, only Capt(0.5)-Zn(25)-MLNC-Fur(0.45) presented a significant difference (p < 0.05) on the first day. On the fifth day, both Capt(0.5)-MLNC-Fur(0.45) and Capt(0.5)-Zn(25)-MLNC-Fur(0.45) had an effect lasting up to 24 h. The analysis of early kidney damage marker showed a potential protection in renal function by Capt(0.5)-Zn(25)-MLNC-Fur(0.45). In conclusion, the formulation Capt(0.5)-Zn(25)-MLNC-Fur(0.45) proved to be suitable for hypertension treatment envisaging an important innovation.

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BACKGROUND: Adenocarcinoma of colon and rectum are one of the most common cancers worldwide, responsible for over 1,300,000 people diagnosed. Also, they are responsible for metastasis, which leads to death in less than 5 years. METHODS: In this study, we developed, characterized, and pre-clinically tested a new nano-radiopharmaceutical for early and differential detection of adenocarcinoma of colon and rectum. RESULTS AND CONCLUSION: Results demonstrated the specificity of the developed nanosystem and the ability to reach the tumor with very specific targeting. Also, the imaging data support the use of this nano-agent as a nanoimaging-guided-radiopharmaceutical.

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Hospital-acquired infections caused by antibiotic-resistant bacteria threaten the lives of many citizens all over the world. Discovery of new agents to hinder bacterial development would have a significant impact on the treatment of infections. Here, the purification and characterization of Rc-2S-Alb, a protein that belongs to the 2S albumin family, from Ricinus communis seed cake, are reported. Rc-2S-Alb was purified after protein extraction with Tris-HCl buffer, pH 7.5, fractionation by ammonium sulfate (50-75%), and chromatography on Phenyl-Sepharose and DEAE-Sepharose. Rc-2S-Alb, a 75 kDa peptide, displays trypsin inhibitory activity and has high in vitro antibacterial activity against Bacillus subtilis, Klebsiella pneumonia, and Pseudomonas aeruginosa, which are important human pathogenic bacteria. Atomic force microscopy studies indicated that Rc-2S-Alb disrupts the bacterial membrane with loss of the cytoplasm content and ultimately bacterial death. Therefore, Rc-2S-Alb is a powerful candidate for the development of an alternative drug that may help reduce hospital-acquired infections.

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MAIN CONCLUSION: The latex from Thevetia peruviana is rich in plant defense proteins, including a 120 kDa cysteine peptidase with structural characteristics similar to germin-like proteins. More than 20,000 plant species produce latex, including Apocynaceae, Sapotaceae, Papaveraceae and Euphorbiaceae. To better understand the physiological role played by latex fluids, a proteomic analysis of Thevetia peruviana (Pers.) Schum latex was performed using two-dimensional gel electrophoresis and mass spectrometry. A total of 33 proteins (86 %) were identified, including storage proteins, a peptidase inhibitor, cysteine peptidases, peroxidases and osmotins. An unusual cysteine peptidase, termed peruvianin-I, was purified from the latex by a single chromatographic step involving gel filtration. The enzyme (glycoprotein) was inhibited by E-64 and iodoacetamide and exhibited high specific activity towards azocasein (K m 17.6 µM), with an optimal pH and temperature of 5.0-6.0 and 25-37 °C, respectively. Gel filtration chromatography, two-dimensional gel electrophoresis, and mass spectrometry revealed that peruvianin-I possesses 120 kDa, pI 4.0, and six subunits (20 kDa). A unique N-terminal amino acid sequence was obtained to oligomer and monomers of peruvianin-I (1ADPGPLQDFCLADLNSPLFINGYPCRNPALAISDDF36). High-resolution images from atomic force microscopy showed the homohexameric structure of peruvianin-I may be organized as a trimer of dimers that form a central channel similar to germin-like proteins. Peruvianin-I exhibited no oxalate oxidase and superoxide dismutase activity or antifungal effects. Peruvianin-I represents the first germin-like protein (GLP) with cysteine peptidase activity, an activity unknown in the GLP family so far.

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IMPORTANCE: There is an increasing need to prolong trabeculectomy success rates with minimally invasive procedures. OBJECTIVE: To investigate the safety and efficacy of Nd:YAG laser goniopuncture (LGP) in lowering intraocular pressure (IOP) in eyes having late bleb failure following trabeculectomy with mitomycin C administration. DESIGN, SETTING, AND PARTICIPANTS: Prospective, noncomparative, interventional cohort at a referral glaucoma practice, including 19 eyes of 19 patients with uncontrolled glaucoma after failed trabeculectomy. INTERVENTIONS: All eyes had ischemic nonfunctioning blebs with patent internal ostia and underwent Nd:YAG LGP, followed by a 5-fluorouracil injection. MAIN OUTCOMES AND MEASURES: The IOP and the number of antiglaucoma medications before and after the procedure, as well as presurgical and postsurgical appearance of the blebs, using the Indiana Bleb Appearance Grading Scale classification. RESULTS: The mean (SD) time of LGP after trabeculectomy was 35.7 (32.3) months, and the mean (SD) follow-up period after LGP was 6.0 (1.1) months (range, 4.4-8.4 months). The mean (SD) IOP had decreased from 20.9 (4.5) mm Hg (range, 15.5-29.0 mm Hg) to 11.9 (4.1) mm Hg (range, 5.0-21.0 mm Hg) (P < .001). The only complications observed after LGP were 2 cases of hypotony, which resolved spontaneously. Compared with baseline Indiana Bleb Appearance Grading Scale classifications, 2 eyes showed an increase in bleb height and 10 eyes showed an increase in bleb extension. None of the eyes had a positive Seidel test result. The mean (SD) number of hypotensive agents per eye had decreased from 0.7 (1.1) to 0.3 (0.7) after the procedure. At the last follow-up visit, 15 eyes (79%) had achieved an IOP of 15 mm Hg or less, with a minimum IOP reduction of 20% from baseline without medication use. CONCLUSIONS AND RELEVANCE: The Nd:YAG LGP is a safe and effective procedure for lowering IOP in eyes with ischemic nonfunctioning blebs and patent trabeculectomy ostia. This is a promising solution to rescue failed trabeculectomies and can potentially prolong trabeculectomy success rates.

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BACKGROUND: The water-drinking test has been used as a stress test to evaluate the drainage system of the eye. However, in order to be clinically applicable,a test must provide reproducible results with consistent measurements. This study was performed to verify the reproducibility of intraocular pressure peaks and fluctuation detected during the water-drinking test in patients with ocular hypertension and open-angle glaucoma. DESIGN: A prospective analysis of patients in a tertiary care unit for glaucoma treatment. PARTICIPANTS: Twenty-four ocular hypertension and 64 open-angle glaucoma patients not under treatment. METHODS: The water-drinking test was performed in 2 consecutive days by the same examiners in patients not under treatment. Reproducibility was assessed using the intraclass correlation coefficient. MAIN OUTCOME MEASURES: Peak and fluctuation of intraocular pressure obtained with the water-drinking test were analysed for reproducibility. RESULTS: Eighty-eight eyes from 24 ocular hypertension and 64 open-angle glaucoma patients not under treatment were evaluated. Test and retest intraocular pressure peak values were 28.38 ± 4.64 and 28.38 ± 4.56 mmHg, respectively (P = 1.00). Test and retest intraocular pressure fluctuation values were 5.75 ± 3.9 and 4.99 ± 2.7 mmHg, respectively (P = 0.06). Based on intraclass coefficient, reproducibility was excellent for peak intraocular pressure (intraclass correlation coefficient = 0.79) and fair for intraocular pressure fluctuation (intraclass correlation coefficient = 0.37). CONCLUSION: Intraocular pressure peaks detected during the water-drinking test presented excellent reproducibility, whereas the reproducibility of fluctuation was considered fair.

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BACKGROUND: Peroxiredoxins have diverse functions in cellular defense-signaling pathways. 2-Cys-peroxiredoxins (2-Cys-Prx) reduce H2O2 and alkyl-hydroperoxide. This study describes the purification and characterization of a genuine 2-Cys-Prx from Vigna unguiculata (Vu-2-Cys-Prx). METHODS: Vu-2-Cys-Prx was purified from leaves by ammonium sulfate fractionation, chitin affinity and ion exchange chromatography. RESULTS: Vu-2-Cys-Prx reduces H2O2 using NADPH and DTT. Vu-2-Cys-Prx is a 44 kDa (SDS-PAGE)/46 kDa (exclusion chromatography) protein that appears as a 22 kDa molecule under reducing conditions, indicating that it is a homodimer linked intermolecularly by disulfide bonds and has a pI range of 4.56­4.72; its NH2-terminal sequence was similar to 2-Cys-Prx from Phaseolus vulgaris (96%) and Populus tricocarpa (96%). Analysis by ESI-Q-TOF MS/MS showed a molecular mass/pI of 28.622 kDa/5.18. Vu-2-Cys-Prx has 8% α-helix, 39% ß-sheet, 22% of turns and 31% of unordered forms. Vu-2-Cys-Prx was heat stable, has optimal activity at pH 7.0, and prevented plasmid DNA degradation. Atomic force microscopy shows that Vu-2-Cys-Prx oligomerized in decamers which might be associated with its molecular chaperone activity that prevented denaturation of insulin and citrate synthase. Its cDNA analysis showed that the redox-active Cys52 residue and the amino acids Pro45, Thr49 and Arg128 are conserved as in other 2-Cys-Prx. GENERAL SIGNIFICANCE: The biochemical and molecular features of Vu-2-Cys-Prx are similar to other members of 2-Cys-Prx family. To date, only one publication reported on the purification of native 2-Cys-Prx from leaves and the subsequent analysis by N-terminal Edman sequencing, which is crucial for construction of stromal recombinant 2-Cys-Prx proteins.

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