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Franca-Oliveira G, Monreal Peinado S, Alves de Souza SM, Kalume DE, Ferraz de Souza TL, Hernández-Ledesma B, Martinez-Rodriguez AJ. Proteomic Characterization of a Lunasin-Enriched Soybean Extract Potentially Useful in the Treatment of Helicobacter pylori Infection. Nutrients 2024; 16:2056. [PMID: 38999803 PMCID: PMC11242994 DOI: 10.3390/nu16132056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 06/21/2024] [Accepted: 06/25/2024] [Indexed: 07/14/2024] Open
Abstract
Helicobacter pylori infection affects over 50% of the world's population and leads to chronic inflammation and gastric disorders, being the main pathogen correlated to gastric cancer development. Increasing antibiotic resistance levels are a major global concern and alternative treatments are needed. Soybean peptides and other compounds might be an alternative in the treatment to avoid, eradicate and/or control symptoms of H. pylori infection. This study aimed to characterize a lunasin-enriched soybean extract (LSE) using proteomics tools and to evaluate its antioxidant, anti-inflammatory and antibacterial properties against H. pylori infection. By LC-MS/MS analysis, 124 proteins were identified, with 2S albumin (lunasin and large-chain subunits) being the fourth most abundant protein (8.9%). Lunasin consists of 44 amino acid residues and an intramolecular disulfide bond. LSE at a low dose (0.0625 mg/mL) reduced ROS production in both H. pylori-infected and non-infected AGS gastric cells. This led to a significant reduction of 6.71% in the levels of pro-inflammatory interleukin (IL)-8. LSE also showed antibacterial activity against H. pylori, which can be attributed to other soybean proteins and phenolic compounds. Our findings suggest that LSE might be a promising alternative in the management of H. pylori infection and its associated symptoms.
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Affiliation(s)
- Giselle Franca-Oliveira
- Institute of Food Science Research (CIAL, CSIC-UAM, CEI UAM + CSIC), Nicolás Cabrera 9, 28049 Madrid, Spain
| | - Sara Monreal Peinado
- Institute of Food Science Research (CIAL, CSIC-UAM, CEI UAM + CSIC), Nicolás Cabrera 9, 28049 Madrid, Spain
| | - Stephanny Miranda Alves de Souza
- Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Programa de Pós-Graduação em Nanobiossistemas, Universidade Federal do Rio de Janeiro, Duque de Caxias 25240-005, Brazil
| | - Dario Eluan Kalume
- Laboratório Interdisciplinar de Pesquisas Médicas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro 21041-250, Brazil
| | - Theo Luiz Ferraz de Souza
- Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Programa de Pós-Graduação em Nanobiossistemas, Universidade Federal do Rio de Janeiro, Duque de Caxias 25240-005, Brazil
| | - Blanca Hernández-Ledesma
- Institute of Food Science Research (CIAL, CSIC-UAM, CEI UAM + CSIC), Nicolás Cabrera 9, 28049 Madrid, Spain
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Parisi MG, Ozón B, Vera González SM, García-Pardo J, Obregón WD. Plant Protease Inhibitors as Emerging Antimicrobial Peptide Agents: A Comprehensive Review. Pharmaceutics 2024; 16:582. [PMID: 38794245 PMCID: PMC11125377 DOI: 10.3390/pharmaceutics16050582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Revised: 04/16/2024] [Accepted: 04/18/2024] [Indexed: 05/26/2024] Open
Abstract
Antimicrobial peptides (AMPs) are important mediator molecules of the innate defense mechanisms in a wide range of living organisms, including bacteria, mammals, and plants. Among them, peptide protease inhibitors (PPIs) from plants play a central role in their defense mechanisms by directly attacking pathogens or by modulating the plant's defense response. The growing prevalence of microbial resistance to currently available antibiotics has intensified the interest concerning these molecules as novel antimicrobial agents. In this scenario, PPIs isolated from a variety of plants have shown potential in inhibiting the growth of pathogenic bacteria, protozoans, and fungal strains, either by interfering with essential biochemical or physiological processes or by altering the permeability of biological membranes of invading organisms. Moreover, these molecules are active inhibitors of a range of proteases, including aspartic, serine, and cysteine types, with some showing particular efficacy as trypsin and chymotrypsin inhibitors. In this review, we provide a comprehensive analysis of the potential of plant-derived PPIs as novel antimicrobial molecules, highlighting their broad-spectrum antimicrobial efficacy, specificity, and minimal toxicity. These natural compounds exhibit diverse mechanisms of action and often multifunctionality, positioning them as promising molecular scaffolds for developing new therapeutic antibacterial agents.
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Affiliation(s)
- Mónica G. Parisi
- Instituto de Ecología y Desarrollo Sustentable (INEDES, CONICET-UNLu) and Departamento de Ciencias Básicas, Universidad Nacional de Luján, Ruta 5 y Avenida Constitución, Luján B6700, Buenos Aires, Argentina;
| | - Brenda Ozón
- Centro de Investigación de Proteínas Vegetales (CIProVe) and Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115 s/N, La Plata B1900, Buenos Aires, Argentina; (B.O.); (S.M.V.G.)
| | - Sofía M. Vera González
- Centro de Investigación de Proteínas Vegetales (CIProVe) and Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115 s/N, La Plata B1900, Buenos Aires, Argentina; (B.O.); (S.M.V.G.)
| | - Javier García-Pardo
- Institut de Biotecnologia i de Biomedicina (IBB) and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Walter David Obregón
- Centro de Investigación de Proteínas Vegetales (CIProVe) and Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115 s/N, La Plata B1900, Buenos Aires, Argentina; (B.O.); (S.M.V.G.)
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3
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van Niekerk AA, Maluck S, Mag P, Kővágó C, Kerek Á, Jerzsele Á, Steinmetzer T, Pászti-Gere E. Antiviral Drug Candidate Repositioning for Streptococcus suis Infection in Non-Tumorigenic Cell Models. Biomedicines 2024; 12:783. [PMID: 38672139 PMCID: PMC11048155 DOI: 10.3390/biomedicines12040783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/28/2024] [Accepted: 03/29/2024] [Indexed: 04/28/2024] Open
Abstract
The increasing prevalence of antimicrobial resistance against zoonotic bacteria, including Streptococcus (S.) suis, highlights the need for new therapeutical strategies, including the repositioning of drugs. In this study, susceptibilities of bacterial isolates were tested toward ten different 3-amidinophenyalanine (Phe(3-Am)) derivatives via determination of minimum inhibitory concentration (MIC) values. Some of these protease inhibitors, like compounds MI-432, MI-471, and MI-476, showed excellent antibacterial effects against S. suis. Their drug interaction potential was investigated using human liver microsomal cytochrome P450 (CYP450) measurements. In our work, non-tumorigenic IPEC-J2 cells and primary porcine hepatocytes were infected with S. suis, and the putative beneficial impact of these inhibitors was investigated on cell viability (Neutral red assay), on interleukin (IL)-6 levels (ELISA technique), and on redox balance (Amplex red method). The antibacterial inhibitors prevented S. suis-induced cell death (except MI-432) and decreased proinflammatory IL-6 levels. It was also found that MI-432 and MI-476 had antioxidant effects in an intestinal cell model upon S. suis infection. Concentration-dependent suppression of CYP3A4 function was found via application of all three inhibitors. In conclusion, our study suggests that the potential antiviral Phe(3-Am) derivatives with 2',4' dichloro-biphenyl moieties can be considered as effective drug candidates against S. suis infection due to their antibacterial effects.
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Affiliation(s)
- Ashley Anzet van Niekerk
- Department of Pharmacology and Toxicology, University of Veterinary Medicine, István utca 2, H-1078 Budapest, Hungary (Á.J.)
| | - Sara Maluck
- Department of Pharmacology and Toxicology, University of Veterinary Medicine, István utca 2, H-1078 Budapest, Hungary (Á.J.)
| | - Patrik Mag
- Department of Pharmacology and Toxicology, University of Veterinary Medicine, István utca 2, H-1078 Budapest, Hungary (Á.J.)
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, University of Veterinary Medicine, István utca 2, H-1078 Budapest, Hungary
| | - Csaba Kővágó
- Department of Pharmacology and Toxicology, University of Veterinary Medicine, István utca 2, H-1078 Budapest, Hungary (Á.J.)
| | - Ádám Kerek
- Department of Pharmacology and Toxicology, University of Veterinary Medicine, István utca 2, H-1078 Budapest, Hungary (Á.J.)
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, University of Veterinary Medicine, István utca 2, H-1078 Budapest, Hungary
| | - Ákos Jerzsele
- Department of Pharmacology and Toxicology, University of Veterinary Medicine, István utca 2, H-1078 Budapest, Hungary (Á.J.)
- National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, University of Veterinary Medicine, István utca 2, H-1078 Budapest, Hungary
| | - Torsten Steinmetzer
- Faculty of Pharmacy, Institute of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, 35032 Marburg, Germany
| | - Erzsébet Pászti-Gere
- Department of Pharmacology and Toxicology, University of Veterinary Medicine, István utca 2, H-1078 Budapest, Hungary (Á.J.)
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4
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Matias LLR, Damasceno KSFDSC, Pereira AS, Passos TS, Morais AHDA. Innovative Biomedical and Technological Strategies for the Control of Bacterial Growth and Infections. Biomedicines 2024; 12:176. [PMID: 38255281 PMCID: PMC10813423 DOI: 10.3390/biomedicines12010176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/05/2024] [Accepted: 01/11/2024] [Indexed: 01/24/2024] Open
Abstract
Antibiotics comprise one of the most successful groups of pharmaceutical products. Still, they have been associated with developing bacterial resistance, which has become one of the most severe problems threatening human health today. This context has prompted the development of new antibiotics or co-treatments using innovative tools to reverse the resistance context, combat infections, and offer promising antibacterial therapy. For the development of new alternatives, strategies, and/or antibiotics for controlling bacterial growth, it is necessary to know the target bacteria, their classification, morphological characteristics, the antibiotics currently used for therapies, and their respective mechanisms of action. In this regard, genomics, through the sequencing of bacterial genomes, has generated information on diverse genetic resources, aiding in the discovery of new molecules or antibiotic compounds. Nanotechnology has been applied to propose new antimicrobials, revitalize existing drug options, and use strategic encapsulating agents with their biochemical characteristics, making them more effective against various bacteria. Advanced knowledge in bacterial sequencing contributes to the construction of databases, resulting in advances in bioinformatics and the development of new antimicrobials. Moreover, it enables in silico antimicrobial susceptibility testing without the need to cultivate the pathogen, reducing costs and time. This review presents new antibiotics and biomedical and technological innovations studied in recent years to develop or improve natural or synthetic antimicrobial agents to reduce bacterial growth, promote well-being, and benefit users.
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Affiliation(s)
- Lídia Leonize Rodrigues Matias
- Biochemistry and Molecular Biology Postgraduate Program, Biosciences Center, Federal University of Rio Grande do Norte, Natal 59078-970, RN, Brazil;
| | | | - Annemberg Salvino Pereira
- Nutrition Course, Center for Health Sciences, Federal University of Rio Grande do Norte, Natal 59078-970, RN, Brazil;
| | - Thaís Souza Passos
- Nutrition Postgraduate Program, Center for Health Sciences, Federal University of Rio Grande do Norte, Natal 59078-970, RN, Brazil; (K.S.F.d.S.C.D.); (T.S.P.)
| | - Ana Heloneida de Araujo Morais
- Biochemistry and Molecular Biology Postgraduate Program, Biosciences Center, Federal University of Rio Grande do Norte, Natal 59078-970, RN, Brazil;
- Nutrition Postgraduate Program, Center for Health Sciences, Federal University of Rio Grande do Norte, Natal 59078-970, RN, Brazil; (K.S.F.d.S.C.D.); (T.S.P.)
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5
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de Souza AÁ, Lima AM, Dede Oliveira BezerraSousa D, Nogueira FC, do Sacramento Neto JC, Dias LP, Araújo NMS, Nagano CS, Júnior HVN, da Silva CR, do Amaral Valente Sá LG, de Andrade Neto JB, Barroso FDD, de Moraes MEA, de Oliveira HD. Chia (Salvia hispanica L.) Seeds Contain a Highly Stable Trypsin Inhibitor with Potential for Bacterial Management Alone or in Drug Combination Therapy with Oxacillin. Probiotics Antimicrob Proteins 2023; 15:1221-1233. [PMID: 35995908 DOI: 10.1007/s12602-022-09979-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2022] [Indexed: 11/26/2022]
Abstract
The emergence of antibiotic resistance poses a serious and challenging threat to healthcare systems, making it imperative to discover novel therapeutic options. This work reports the isolation and characterization of a thermostable trypsin inhibitor from chia (Salvia hispanica L.) seeds, with antibacterial activity against Staphylococcus aureus sensitive and resistant to methicillin. The trypsin inhibitor ShTI was purified from chia seeds through crude extract heat treatment, followed by affinity and reversed-phase chromatography. Tricine-SDS-PAGE revealed a single glycoprotein band of ~ 11 kDa under nonreducing conditions, confirmed by mass spectrometry analysis (11.558 kDa). ShTI was remarkably stable under high temperatures (100 °C; 120 min) and a broad pH range (2-10; 30 min). Upon exposure to DTT (0.1 M; 120 min), ShTI antitrypsin activity was partially lost (~ 38%), indicating the participation of disulfide bridges in its structure. ShTI is a competitive inhibitor (Ki = 1.79 × 10-8 M; IC50 = 1.74 × 10-8 M) that forms a 1:1 stoichiometry ratio for the ShTI:trypsin complex. ShTI displayed antibacterial activity alone (MICs range from 15.83 to 19.03 µM) and in combination with oxacillin (FICI range from 0.20 to 0.33) against strains of S. aureus, including methicillin-resistant strains. Overproduction of reactive oxygen species and plasma membrane pore formation are involved in the antibacterial action mode of ShTI. Overall, ShTI represents a novel candidate for use as a therapeutic agent for the bacterial management of S. aureus infections.
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Affiliation(s)
- Adson Ávila de Souza
- Department of Biochemistry and Molecular Biology, Science Center, Federal University of Ceará, Campus do Pici Prof. Prisco Bezerra, Fortaleza, CE, 60440-900, Brazil
| | - Adrianne Maia Lima
- Department of Biochemistry and Molecular Biology, Science Center, Federal University of Ceará, Campus do Pici Prof. Prisco Bezerra, Fortaleza, CE, 60440-900, Brazil
| | - Daniele Dede Oliveira BezerraSousa
- Department of Biochemistry and Molecular Biology, Science Center, Federal University of Ceará, Campus do Pici Prof. Prisco Bezerra, Fortaleza, CE, 60440-900, Brazil
| | - Francisca Cristiane Nogueira
- Department of Biochemistry and Molecular Biology, Science Center, Federal University of Ceará, Campus do Pici Prof. Prisco Bezerra, Fortaleza, CE, 60440-900, Brazil
| | - José Carlos do Sacramento Neto
- Department of Biochemistry and Molecular Biology, Science Center, Federal University of Ceará, Campus do Pici Prof. Prisco Bezerra, Fortaleza, CE, 60440-900, Brazil
| | - Lucas Pinheiro Dias
- Department of Biochemistry and Molecular Biology, Science Center, Federal University of Ceará, Campus do Pici Prof. Prisco Bezerra, Fortaleza, CE, 60440-900, Brazil
| | - Nadine Monteiro Salgueiro Araújo
- Department of Biochemistry and Molecular Biology, Science Center, Federal University of Ceará, Campus do Pici Prof. Prisco Bezerra, Fortaleza, CE, 60440-900, Brazil
| | - Celso Shiniti Nagano
- Department of Fisher Engineering, Center of Agricultural Sciences, Federal University of Ceará, Campus do Pici Prof. Prisco Bezerra, Fortaleza, CE, 60455-970, Brazil
| | - Hélio Vitoriano Nobre Júnior
- Drug Research and Development Center, Federal University of Ceará, Campus do Porangabussu, Fortaleza, CE, 60430-270, Brazil
| | - Cecília Rocha da Silva
- Drug Research and Development Center, Federal University of Ceará, Campus do Porangabussu, Fortaleza, CE, 60430-270, Brazil
| | | | - João Batista de Andrade Neto
- Drug Research and Development Center, Federal University of Ceará, Campus do Porangabussu, Fortaleza, CE, 60430-270, Brazil
| | - Fátima Daiana Dias Barroso
- Drug Research and Development Center, Federal University of Ceará, Campus do Porangabussu, Fortaleza, CE, 60430-270, Brazil
| | | | - Hermógenes David de Oliveira
- Department of Biochemistry and Molecular Biology, Science Center, Federal University of Ceará, Campus do Pici Prof. Prisco Bezerra, Fortaleza, CE, 60440-900, Brazil.
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6
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Oliveira GSD, Nascimento AMDS, Luz ABS, Aguiar AJFC, Lima MSR, Matias LLR, Amado IR, Passos TS, Damasceno KSFDSC, Monteiro NDKV, Moreira SMG, Pastrana L, Morais AHDA. Prospecting in silico antibacterial activity of a peptide from trypsin inhibitor isolated from tamarind seed. J Enzyme Inhib Med Chem 2023; 38:67-83. [PMID: 36305291 PMCID: PMC9621272 DOI: 10.1080/14756366.2022.2134997] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Bacterial infections have become a global concern, stimulating the growing demand for natural and biologically safe therapeutic agents with antibacterial action. This study was evaluated the genotoxicity of the trypsin inhibitor isolated from tamarind seeds (TTI) and the antibacterial effect of TTI theoric model, number 56, and conformation number 287 (TTIp 56/287) and derived peptides in silico. TTI (0.3 and 0.6 mg.mL−1) did not cause genotoxicity in cells (p > 0.05). In silico, a greater interaction of TTIp 56/287 with the Gram-positive membrane (GP) was observed, with an interaction potential energy (IPE) of −1094.97 kcal.mol−1. In the TTIp 56/287-GP interaction, the Arginine, Threonine (Thr), and Lysine residues presented lower IPE. In molecular dynamics (MD), Peptidotrychyme59 (TVSQTPIDIPIGLPVR) showed an IPE of −518.08 kcal.mol−1 with the membrane of GP bacteria, and the Thr and Arginine residues showed the greater IPE. The results highlight new perspectives on TTI and its derived peptides antibacterial activity.
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Affiliation(s)
- Gerciane Silva de Oliveira
- Postgraduate Program in Nutrition, Health Sciences Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | | | - Anna Beatriz Santana Luz
- Postgraduate Program in Biochemistry and Molecular Biology, Center for Biosciences, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Ana Júlia Felipe Camelo Aguiar
- Postgraduate Program in Biochemistry and Molecular Biology, Center for Biosciences, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Mayara Santa Rosa Lima
- Postgraduate Program in Biochemistry and Molecular Biology, Center for Biosciences, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Lídia Leonize Rodrigues Matias
- Postgraduate Program in Biochemistry and Molecular Biology, Center for Biosciences, Federal University of Rio Grande do Norte, Natal, Brazil
| | | | - Thais Souza Passos
- Postgraduate Program in Nutrition, Health Sciences Center, Federal University of Rio Grande do Norte, Natal, Brazil
- Nutrition Department, University Center of Rio Grande do Norte, Natal, Brazil
| | | | | | - Susana Margarida Gomes Moreira
- Postgraduate Program in Biochemistry and Molecular Biology, Center for Biosciences, Federal University of Rio Grande do Norte, Natal, Brazil
- The Doctoral Program of Northeast Network in Biotechnology (RENORBIO), Natal, Brazil
| | - Lorenzo Pastrana
- International Iberian Nanotechnology Laboratory, Braga, Portugal
| | - Ana Heloneida de Araújo Morais
- Postgraduate Program in Nutrition, Health Sciences Center, Federal University of Rio Grande do Norte, Natal, Brazil
- Postgraduate Program in Biochemistry and Molecular Biology, Center for Biosciences, Federal University of Rio Grande do Norte, Natal, Brazil
- Nutrition Department, University Center of Rio Grande do Norte, Natal, Brazil
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Retout M, Jin Z, Tsujimoto J, Mantri Y, Borum R, Creyer MN, Yim W, He T, Chang YC, Jokerst JV. Di-Arginine Additives for Dissociation of Gold Nanoparticle Aggregates: A Matrix-Insensitive Approach with Applications in Protease Detection. ACS APPLIED MATERIALS & INTERFACES 2022; 14:52553-52565. [PMID: 36346346 PMCID: PMC10464667 DOI: 10.1021/acsami.2c17531] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
We report the reversible aggregation of gold nanoparticles (AuNPs) assemblies via a di-arginine peptide additive and thiolated PEGs (HS-PEGs). The AuNPs were first aggregated by attractive forces between the citrate-capped surface and the arginine side chains. We found that the HS-PEG thiol group has a higher affinity for the AuNP surface, thus leading to redispersion and colloidal stability. In turn, there was a robust and obvious color change due to on/off plasmonic coupling. The assemblies' dissociation was directly related to the HS-PEG structural properties such as their size or charge. As an example, HS-PEGs with a molecular weight below 1 kDa could dissociate 100% of the assemblies and restore the exact optical properties of the initial AuNP suspension (prior to the assembly). Surprisingly, the dissociation capacity of HS-PEGs was not affected by the composition of the operating medium and could be performed in complex matrices such as plasma, saliva, bile, urine, cell lysates, or even seawater. The high affinity of thiols for the gold surface encompasses by far the one of endogenous molecules and is thus favored. Moreover, starting with AuNPs already aggregated ensured the absence of a background signal as the dissociation of the assemblies was far from spontaneous. Remarkably, it was possible to dry the AuNP assemblies and solubilize them back with HS-PEGs, improving the colorimetric signal generation. We used this system for protease sensing in biological fluids. Trypsin was chosen as the model enzyme, and highly positively charged peptides were conjugated to HS-PEG molecules as cleavage substrates. The increase of positive charge of the HS-PEG-peptide conjugate quenched the dissociation capacity of the HS-PEG molecules, which could only be restored by the proteolytic cleavage. Picomolar limit of detection was obtained as well as the detection in saliva or urine.
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Affiliation(s)
- Maurice Retout
- Department of NanoEngineering, University of California, San Diego, La Jolla, California92093, United States
| | - Zhicheng Jin
- Department of NanoEngineering, University of California, San Diego, La Jolla, California92093, United States
| | - Jason Tsujimoto
- Department of Bioengineering, University of California, San Diego, La Jolla, California92093, United States
| | - Yash Mantri
- Department of Bioengineering, University of California, San Diego, La Jolla, California92093, United States
| | - Raina Borum
- Department of NanoEngineering, University of California, San Diego, La Jolla, California92093, United States
| | - Matthew N Creyer
- Department of NanoEngineering, University of California, San Diego, La Jolla, California92093, United States
| | - Wonjun Yim
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, California92093, United States
| | - Tengyu He
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, California92093, United States
| | - Yu-Ci Chang
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, California92093, United States
| | - Jesse V Jokerst
- Department of NanoEngineering, University of California, San Diego, La Jolla, California92093, United States
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, California92093, United States
- Department of Radiology, University of California, San Diego, La Jolla, California92093, United States
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