Identification of Low Molecular Weight Proteins and Peptides from Schistosoma mekongi Worm, Egg and Infected Mouse Sera

Schistosoma mekongi is found in the lower Mekong river region and causes schistosomiasis. Low sensitivity of diagnosis and development of drug resistance are problems to eliminate this disease. To develop novel therapies and diagnostics for S. mekongi, the basic molecular biology of this pathogen needs to be explored. Bioactive peptides have been reported in several worms and play important roles in biological functions. Limited information is available on the S. mekongi peptidome. Therefore, this study aimed to identify S. mekongi peptides using in silico transcriptome mining and mass spectrometry approaches. Schistosoma peptide components were identified in adult worms, eggs, and infected mouse sera. Thirteen neuropeptide families were identified using in silico predictions from in-house transcriptomic databases of adult S. mekongi worms. Using mass spectrometry approaches, 118 peptides (from 54 precursor proteins) and 194 peptides (from 86 precursor proteins) were identified from adult worms and eggs, respectively. Importantly, eight unique peptides of the S. mekongi ubiquitin thioesterase, trabid, were identified in infected mouse sera 14, 28, and 56 days after infection. This protein may be a potential target for diagnosis of schistosomiasis. The S. mekongi peptide profiles determined in this study could be used for further drug and diagnostic development

Proteomics of Gnathostomiasis: A Way Forward for Diagnosis and Treatment Development

Gnathostoma spinigerum is the most common cause of gnathostomiasis in humans. It has a complex life cycle, which requires two intermediate hosts and a definitive host, and poses a high risk for zoonosis. Definitive prognosis of gnathostomiasis relies mainly on the isolation of advanced-stage larvae (aL3), which is very challenging especially if the aL3 is sequestered in difficult-to-reach organs. There is also a lack of a confirmatory diagnostic test for gnathostomiasis. With the ongoing advancement of proteomics, a potential diagnostic approach is underway using immunoproteomics and immunodiagnostics. In addition to this, the employment of mass spectrometry could further elucidate not only understanding the biology of the parasite but also determining potential targets of prospective drugs and vaccines. This article reports the past, present, and future application of proteomics in the study of gnathostomiasis

Altered proteome of a Burkholderia pseudomallei mutant defective in short-chain dehydrogenase affects cell adhesion, biofilm formation and heat stress tolerance

Burkholderia pseudomallei is a Gram-negative bacillus that causes melioidosis and is recognized as an important public health problem in southeast Asia and northeast Australia. The treatment of B. pseudomallei infection is hampered by resistance to a wide range of antimicrobial agents and no vaccine is currently available. At present, the underlying mechanisms of B. pseudomallei pathogenesis are poorly understood. In our previous study, we reported that a B. pseudomallei short-chain dehydrogenase (SDO; BPSS2242) mutant constructed by deletion mutagenesis showed reduced B. pseudomallei invasion and initial intracellular survival. This indicated that SDO is associated with the pathogenesis of melioidosis. In the present study, the role of B. pseudomallei SDO was further investigated using the SDO deletion mutant by a proteomic approach. The protein profiles of the SDO mutant and wild-type K96243 were investigated through gel-based proteomic analysis. Quantitative intensity analysis of three individual cultures of the B. pseudomallei SDO mutant revealed significant down-regulation of five protein spots compared with the wild-type. Q-TOF MS/MS identified the protein spots as a glutamate/aspartate ABC transporter, prolyl-tRNA synthetase, Hsp70 family protein, quinone oxidoreductase and a putative carboxypeptidase. Functional assays were performed to investigate the role of these differentially expressed proteins in adhesion to host cells, biofilm induction and survival under heat stress conditions. The SDO deletion mutant showed a decreased ability to adhere to host cells. Moreover, biofilm formation and the survival rate of bacteria under heat stress conditions were also reduced in the mutant strain. Our findings provide insight into the role of SDO in the survival and pathogenesis of B. pseudomallei at the molecular level, which may be applied to the prevention and control of B. pseudomallei infection

Effect of Praziquantel on Schistosoma mekongi Proteome and Phosphoproteome

Schistosoma mekongi causes schistosomiasis in southeast Asia, against which praziquantel (PZQ) is the only treatment option. PZQ resistance has been reported, thus increasing the requirement to understand mechanism of PZQ. Herein, this study aimed to assess differences in proteome and phosphoproteome of S. mekongi after PZQ treatment for elucidating its action. Furthermore, key kinases related to PZQ effects were predicted to identify alternative targets for novel drug development. Proteomes of S. mekongi were profiled after PZQ treatment at half maximal inhibitory concentration and compared with untreated worms. A total of 144 proteins were differentially expressed after treatment. In parallel, immunohistochemistry indicated a reduction of phosphorylation, with 43 phosphoproteins showing reduced phosphorylation, as identified by phosphoproteomic approach. Pathway analysis of mass spectrometric data showed that calcium homeostasis, worm antigen, and oxidative stress pathways were influenced by PZQ treatment. Interestingly, two novel mechanisms related to protein folding and proteolysis through endoplasmic reticulum-associated degradation pathways were indicated as a parasiticidal mechanism of PZQ. According to kinase–substrate predictions with bioinformatic tools, Src kinase was highlighted as the major kinase related to the alteration of phosphorylation by PZQ. Interfering with these pathways or applying Src kinase inhibitors could be alternative approaches for further antischistosomal drug development

Sericin coated thin polymeric films reduce keratinocyte proliferation via the mTOR pathway and epidermal inflammation through IL17 signaling in psoriasis rat model

Abstract Therapeutic treatment forms can play significant roles in resolving psoriatic plaques or promoting wound repair in psoriatic skin. Considering the biocompatibility, mechanical strength, flexibility, and adhesive properties of silk fibroin sheets/films, it is useful to combine them with anti-psoriatic agents and healing stimulants, notably silk sericin. Here, we evaluate the curative properties of sericin-coated thin polymeric films (ScF) fabricated from silk fibroin, using an imiquimod-induced psoriasis rat model. The film biocompatibility and psoriatic wound improvement capacity was assessed. A proteomics study was performed to understand the disease resolving mechanisms. Skin-implantation study exhibited the non-irritation property of ScF films, which alleviate eczema histopathology. Immunohistochemical and gene expression revealed the depletion of β-defensin, caspase-3 and -9, TNF-α, CCL-20, IL-1β, IL-17, TGF-β, and Wnt expressions and S100a14 mRNA level. The proteomics study suggested that ScF diminish keratinocyte proliferation via the mTOR pathway by downregulating mTOR protein, corresponding to the modulation of TNF-α, Wnt, and IL-1β levels, leading to the enhancement of anti-inflammatory environment by IL-17 downregulation. Hematology data demonstrated the safety of using these biomaterials, which provide a potential therapeutic-option for psoriasis treatment due to desirable effects, especially anti-proliferation and anti-inflammation, functioning via the mTOR pathway and control of IL-17 signaling

Proteomic Analysis and Molecular Dynamics Simulation of Riboflavin-Coated Superparamagnetic Iron Oxide Nanoparticles Reveal Human Serum-Derived Protein Coronas: Implications as Magnetic Resonance Imaging Contrast Agents

Superparamagnetic iron oxide nanoparticles (SPIONs) have been increasingly used as nanomedicine platforms due to their exceptional magnetic properties, which emerged from their nanoscopic sizes. Recently, SPIONs with a riboflavin (Rf)-citrate ligand were developed and showed increased internalization in breast cancer cells, with exceptional properties as T2 contrast agents for magnetic resonance imaging (MRI). The interactions of the Rf-coated SPIONs with proteins from fetal bovine serum (FBS) were previously characterized to understand how the nanoparticles will interact with biomolecules. To closer mimic the human biological environments, human serum (HS) has been suggested as a better model. Therefore, in this work, protein coronas of bare, citrate-coated, and Rf-coated SPIONs formed with HS were studied by proteomic analysis to identify and quantify the nanoparticle-protein interaction. The results were compared with the FBS-derived coronas to understand the differences in the protein corona formation from different serum origins. Furthermore, the interactions of the SPIONs with riboflavin carrier protein (RCP), which is a target protein for the Rf-SPIONs, were also studied. The overall physical properties of the corona proteins were similar between the FBS and HS groups, but some specific homologous proteins interacted differently. The RCP was found to bind more to the citrate-coated SPIONs than the Rf-coated one. The outcome could be explained by molecular dynamics simulation, where the orientation of the Rf ligand did not favor the binding with RCP. The simulation results also showed the influence of surface hydrophilicity of the SPIONs on the RCP interaction. The combined data from proteomic and simulation analyses suggested a way to improve the Rf ligand to enhance the interaction with RCP and reduce the interactions with the serum proteins, which could enhance the specific cellular interactions and improve the Rf-SPIONs as MRI contrast agents for breast cancer.This project was funded by the National Research Council of Thailand (NRCT) with Mahidol University: N42A650357. This research project was supported by Mahidol University (MU’s Strategic Research Fund): 2023. Partial support was also provided by the CIF and CNI grant, Faculty of Science, Mahidol University. W.M. was supported by the Science Achievement Scholarship of Thailand. The authors thank Prof. Dr. Chutima Kuhakarn for the support of the facilities for the synthesis of the Rf-citrate ligand.With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).Peer reviewe

Mass spectrometry-based identification and whole-genome characterisation of the first pteropine orthoreovirus isolated from monkey faeces in Thailand

Abstract Background The pteropine orthoreovirus (PRV) was isolated from monkey (Macaca fascicularis) faecal samples collected from human-inhabited areas in Lopburi Province, Thailand. These samples were initially obtained to survey for the presence of hepatitis E virus (HEV). Results Two virus isolates were retrieved by virus culture of 55 monkey faecal samples. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was successfully used to identify the viruses as the segmented dsRNA orthoreovirus. Phylogenetic analysis of the Lopburi orthoreovirus whole-genomes revealed relationships with the well-characterised PRVs Pulau (segment L1), Cangyuan (segments L2, M3 and S3), Melaka (segments L3 and M2), Kampar (segments M1 and S2) and Sikamat (segments S1 and S4) of Southeast Asia and China with nucleotide sequence identities of 93.5–98.9%. RT-PCR showed that PRV was detected in 10.9% (6/55) and HEV was detected in 25.5% (14/55) of the monkey faecal samples. Conclusions PRV was isolated from monkey faeces for the first time in Thailand via viral culture and LC-MS/MS. The genetic diversity of the virus genome segments suggested a re-assortment within the PRV species group. The overall findings emphasise that monkey faeces can be sources of zoonotic viruses, including PRV and HEV, and suggest the need for active virus surveillance in areas of human and monkey co-habitation to prevent and control emerging zoonotic diseases in the future

Evaluation of Immunodiagnostic Performances of <i>Neospora caninum</i> Peroxiredoxin 2 (NcPrx2), Microneme 4 (NcMIC4), and Surface Antigen 1 (NcSAG1) Recombinant Proteins for Bovine Neosporosis

Bovine neosporosis is among the main causes of abortion in cattle worldwide, causing serious economic losses in the beef and dairy industries. A highly sensitive and specific diagnostic method for the assessment of the epidemiology of the disease, as well as it surveillance and management, is imperative, due to the absence of an effective treatment or vaccine against neosporosis. In the present study, the immunodiagnostic performance of Neospora caninum peroxiredoxin 2 (NcPrx2), microneme 4 (NcMIC4), and surface antigen 1 (NcSAG1) to detect IgG antibodies against N. caninum in cattle were evaluated and compared with that of the indirect fluorescent antibody test (IFAT). The results revealed that NcSAG1 had the highest sensitivity and specificity, with values of 88.4% and 80.7%, respectively, followed by NcPrx2, with a high sensitivity of 87.0% but a low specificity of 67.0%, whereas NcMIC4 showed sensitivity and specificity of 84.1% and 78.9%, respectively, when compared with IFAT. A high degree of agreement was observed for NcSAG1 (k = 0.713) recombinant protein, showing the highest diagnostic capability, followed by NcMIC4 (k = 0.64) and NcPrx2 (k = 0.558). The present study demonstrates that NcSAG1 is helpful as an antigen marker and also demonstrates the potential immunodiagnostic capabilities of NcPrx2 and NcMIC4, which could serve as alternative diagnostic markers for detecting N. caninum infection in cattle. These markers may find utility in future treatment management, surveillance, and risk assessment of neosporosis in livestock or other animal host species. Further research should be directed toward understanding the in vivo immune response differences resulting from immunization with both recombinant proteins