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Jagels A, Adpressa DA, Kaweesa EN, McCauley M, Philmus B, Strother JA, Loesgen S. Metabolomics-Guided Discovery, Isolation, Structure Elucidation, and Bioactivity of Myropeptins C-E from Myrothecium inundatum. JOURNAL OF NATURAL PRODUCTS 2023; 86:1723-1735. [PMID: 37411007 DOI: 10.1021/acs.jnatprod.3c00148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/08/2023]
Abstract
The saprotrophic filamentous fungus Myrothecium inundatum represents a chemically underexplored ascomycete with a high number of putative biosynthetic gene clusters in its genome. Here, we present new linear lipopeptides from nongenetic gene activation experiments using nutrient and salt variations. Metabolomics studies revealed four myropeptins, and structural analyses by NMR, HRMS, Marfey's analysis, and ECD assessment for their helical properties established their absolute configuration. A myropeptin biosynthetic gene cluster in the genome was identified. The myropeptins exhibit general nonspecific toxicity against all cancer cell lines in the NCI-60 panel, larval zebrafish with EC50 concentrations of 5-30 μM, and pathogenic bacteria and fungi (MICs of 4-32 μg/mL against multidrug-resistant S. aureus and C. auris). In vitro hemolysis, cell viability, and ionophore assays indicate that the myropeptins target mitochondrial and cellular membranes, inducing cell depolarization and cell death. The toxic activity is modulated by the length of the lipid side chain, which provides valuable insight into their structure-activity relationships.
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Affiliation(s)
- Annika Jagels
- Department of Chemistry, Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida 32080, United States
| | | | - Elizabeth N Kaweesa
- Department of Chemistry, Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida 32080, United States
| | - Mark McCauley
- Department of Chemistry, Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida 32080, United States
| | - Benjamin Philmus
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, Oregon 97331, United States
| | - James A Strother
- Department of Biology, Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida 32080, United States
| | - Sandra Loesgen
- Department of Chemistry, Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, Florida 32080, United States
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Oba M, Nakajima S, Misao K, Yokoo H, Tanaka M. Effect of helicity and hydrophobicity on cell-penetrating ability of arginine-rich peptides. Bioorg Med Chem 2023; 91:117409. [PMID: 37441862 DOI: 10.1016/j.bmc.2023.117409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/15/2023]
Abstract
Arginine (Arg)-rich peptides are one of the typical cell-penetrating peptides (CPPs), which can deliver membrane-impermeable compounds into intracellular compartments. Guanidino groups in Arg-rich peptides are critical for their high cell-penetrating ability, although it remains unclear whether peptide secondary structures contribute to this ability. In the current study, we designed four Arg-rich peptides containing α,α-disubstituted α-amino acids (dAAs), which prefer to adopt a helical structure. The four dAA-containing peptides adopted slightly different peptide secondary structures, from a random structure to a helical structure, with different hydrophobicities. In these peptides, dipropylglycine-containing peptide exhibited the highest helicity and hydrophobicity, and showed the best cell-penetrating ability. These findings suggested that the helicity and hydrophobicity of Arg-rich peptides contributes to their high cell-penetrating ability.
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Affiliation(s)
- Makoto Oba
- Medical Chemistry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 1-5 Shimogamohangi-cho, Sakyo-ku, Kyoto 606-0823, Japan.
| | - Shun Nakajima
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Kurumi Misao
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Hidetomo Yokoo
- Medical Chemistry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 1-5 Shimogamohangi-cho, Sakyo-ku, Kyoto 606-0823, Japan
| | - Masakazu Tanaka
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
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3
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A Novel pH-Tunable Secondary Conformation Containing Mixed Micellar System in Anticancer Treatment. Cancers (Basel) 2020; 12:cancers12020503. [PMID: 32098177 PMCID: PMC7072654 DOI: 10.3390/cancers12020503] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 02/17/2020] [Accepted: 02/18/2020] [Indexed: 12/12/2022] Open
Abstract
In this study, for the first time, we precisely assembled the poly-γ-benzyl-l-glutamate and an amphiphilic copolymer d-α-tocopherol polyethylene glycol succinate into a mixed micellar system for the embedment of the anticancer drug doxorubicin. Importantly, the intracellular drug-releasing behaviors could be controlled by changing the secondary structures of poly-γ-benzyl-l-glutamate via the precise regulation of the buffer’s pH value. Under neutral conditions, the micellar architectures were stabilized by both α-helix secondary structures and the microcrystalline structures. Under acidic conditions (pH 4.0), the interior structures transformed into a coil state with a disordered alignment, inducing the release of the loaded drug. A remarkable cytotoxicity of the Dox-loaded mixed micelles was exhibited toward human lung cancer cells in vitro. The internalizing capability into the cancer cells, as well as the intracellular drug-releasing behaviors, were also identified and observed. The secondary structures containing Dox-loaded mixed micelles had an outstanding antitumor efficacy in human lung cancer A549 cells-bearing nude mice, while little toxicities occurred or interfered with the hepatic or renal functions after the treatments. Thus, these pH-tunable α-helix-containing mixed micelles are innovative and promising for controlled intracellular anticancer drug delivery.
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Yoshimura A, Nishimura S, Suzuki T, Hattori A, Dohmae N, Kato T, Kakeya H. Isolation, Structure Elucidation, and Conformational Regulation of Myropeptins, Lipopeptides from the Fungus Myrothecium roridum. Org Lett 2019; 21:7524-7528. [PMID: 31497968 DOI: 10.1021/acs.orglett.9b02801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Myropeptins, novel lipopeptides, were isolated from the culture broth of a fungus Myrothecium roridum F27113. Myropeptin A1 comprises a linear 20 amino acid-peptide chain and a lauric acid capping the N-terminus. Myropeptin A1 formed a helix structure and showed biological activities including antifungal and hemolysis. Myropeptin B, a shorter analogue by two amino acid residues, showed neither helicity nor biological activity. These two amino acids at the C-terminus regulate the molecular function of myropeptin A1.
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Affiliation(s)
- Aya Yoshimura
- Department of System Chemotherapy and Molecular Sciences, Division of Bioinformatics and Chemical Genomics, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto 606-8501 , Japan
| | - Shinichi Nishimura
- Department of System Chemotherapy and Molecular Sciences, Division of Bioinformatics and Chemical Genomics, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto 606-8501 , Japan
| | - Takehiro Suzuki
- Biomolecular Characterization Unit , RIKEN Center for Sustainable Resource Science , 2-1 Hirosawa , Wako , Saitama 351-0198 , Japan
| | - Akira Hattori
- Department of System Chemotherapy and Molecular Sciences, Division of Bioinformatics and Chemical Genomics, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto 606-8501 , Japan
| | - Naoshi Dohmae
- Biomolecular Characterization Unit , RIKEN Center for Sustainable Resource Science , 2-1 Hirosawa , Wako , Saitama 351-0198 , Japan
| | - Taira Kato
- Research & Development Division , MicroBioPharm Japan Co., Ltd. , 156 Nakagawara , Kiyosu-shi , Aichi 452-0915 , Japan
| | - Hideaki Kakeya
- Department of System Chemotherapy and Molecular Sciences, Division of Bioinformatics and Chemical Genomics, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto 606-8501 , Japan
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Abstract
Highly efficient drug-delivery tools for membrane-impermeable compounds, proteins, and nucleic acids in living cells are useful in the fields of chemical biology and drug discovery, and such tools have been widely studied. One strategy in the development of novel drug-delivery tools is to utilize cell-penetrating peptide (CPP) foldamers. CPP foldamers are folded oligopeptides that possess cell membrane permeability. In recent decades, a wide variety of CPP foldamers have been reported by many groups. Herein, CPP foldamers are introduced and discussed from the viewpoints of component monomers (amino acids) and their application as drug-delivery tools.
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Affiliation(s)
- Makoto Oba
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan
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Oba M, Nagano Y, Kato T, Tanaka M. Secondary structures and cell-penetrating abilities of arginine-rich peptide foldamers. Sci Rep 2019; 9:1349. [PMID: 30718681 PMCID: PMC6362038 DOI: 10.1038/s41598-018-38063-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 12/19/2018] [Indexed: 11/09/2022] Open
Abstract
Foldamers, which are folded oligomers with well-defined conformations, have been recently reported to have a good cell-penetrating ability. α,α-Disubstituted α-amino acids are one such promising tool for the design of peptide foldamers. Here, we prepared four types of L-arginine-rich nonapeptides containing L-leucine or α,α-disubstituted α-amino acids, and evaluated their secondary structures and cell-penetrating abilities in order to elucidate a correlation between them. Peptides containing α,α-disubstituted α-amino acids had similar resistance to protease digestion but showed different secondary structures. Intracellular uptake assays revealed that the helicity of peptides was important for their cell-penetrating abilities. These findings suggested that a peptide foldamer with a stable helical structure could be promising for the design of cell-penetrating peptides.
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Affiliation(s)
- Makoto Oba
- Graduate School Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan.
| | - Yu Nagano
- Graduate School Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan
| | - Takuma Kato
- Graduate School Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan
- Osaka University of Pharmaceutical Sciences, 40-20-1 Nasahara, Takatsuki, Osaka, 569-1094, Japan
| | - Masakazu Tanaka
- Graduate School Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan
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Pinheiro DL, Nielsen DU, Amarante GW, Skrydstrup T. Pd-catalyzed carbonylative α-arylation of azlactones: A formal four-component coupling route to α,α-disubstituted amino acids. J Catal 2018. [DOI: 10.1016/j.jcat.2018.04.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Oba M, Kunitake M, Kato T, Ueda A, Tanaka M. Enhanced and Prolonged Cell-Penetrating Abilities of Arginine-Rich Peptides by Introducing Cyclic α,α-Disubstituted α-Amino Acids with Stapling. Bioconjug Chem 2017; 28:1801-1806. [PMID: 28603971 DOI: 10.1021/acs.bioconjchem.7b00190] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Cell-penetrating peptides are receiving increasing attention as drug delivery tools, and the search for peptides with high cell-penetrating ability and negligible cytotoxicity has become a critical research topic. Herein, cyclic α,α-disubstituted α-amino acids were introduced into arginine-rich peptides and an additional staple was provided in the side chain. The peptides designed in the present study showed more enhanced and prolonged cell-penetrating abilities than an arginine nonapeptide due to high resistance to protease and conformationally stable helical structures.
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Affiliation(s)
- Makoto Oba
- Graduate School of Biomedical Sciences, Nagasaki University , 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Masayuki Kunitake
- Graduate School of Biomedical Sciences, Nagasaki University , 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Takuma Kato
- Graduate School of Biomedical Sciences, Nagasaki University , 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Atsushi Ueda
- Graduate School of Biomedical Sciences, Nagasaki University , 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Masakazu Tanaka
- Graduate School of Biomedical Sciences, Nagasaki University , 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
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Antisense Oligonucleotide-based Splice Correction for USH2A-associated Retinal Degeneration Caused by a Frequent Deep-intronic Mutation. MOLECULAR THERAPY. NUCLEIC ACIDS 2016; 5:e381. [PMID: 27802265 DOI: 10.1038/mtna.2016.89] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 09/07/2016] [Indexed: 12/21/2022]
Abstract
Usher syndrome (USH) is the most common cause of combined deaf-blindness in man. The hearing loss can be partly compensated by providing patients with hearing aids or cochlear implants, but the loss of vision is currently untreatable. In general, mutations in the USH2A gene are the most frequent cause of USH explaining up to 50% of all patients worldwide. The first deep-intronic mutation in the USH2A gene (c.7595-2144A>G) was reported in 2012, leading to the insertion of a pseudoexon (PE40) into the mature USH2A transcript. When translated, this PE40-containing transcript is predicted to result in a truncated non-functional USH2A protein. In this study, we explored the potential of antisense oligonucleotides (AONs) to prevent aberrant splicing of USH2A pre-mRNA as a consequence of the c.7595-2144A>G mutation. Engineered 2'-O-methylphosphorothioate AONs targeting the PE40 splice acceptor site and/or exonic splice enhancer regions displayed significant splice correction potential in both patient derived fibroblasts and a minigene splice assay for USH2A c.7595-2144A>G, whereas a non-binding sense oligonucleotide had no effect on splicing. Altogether, AON-based splice correction could be a promising approach for the development of a future treatment for USH2A-associated retinitis pigmentosa caused by the deep-intronic c.7595-2144A>G mutation.
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Vemula H, Kitase Y, Ayon NJ, Bonewald L, Gutheil WG. Gaussian and linear deconvolution of LC-MS/MS chromatograms of the eight aminobutyric acid isomers. Anal Biochem 2016; 516:75-85. [PMID: 27771391 DOI: 10.1016/j.ab.2016.10.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 10/18/2016] [Indexed: 10/20/2022]
Abstract
Isomeric molecules present a challenge for analytical resolution and quantification, even with MS-based detection. The eight aminobutyric acid (ABA) isomers are of interest for their various biological activities, particularly γ-aminobutyric acid (GABA) and the d- and l-isomers of β-aminoisobutyric acid (β-AIBA; BAIBA). This study aimed to investigate LC-MS/MS-based resolution of these ABA isomers as their Marfey's (Mar) reagent derivatives. HPLC was able to separate three Mar-ABA isomers l-β-ABA (l-BABA), and l- and d-α-ABA (AABA) completely, with three isomers (GABA, and d/l-BAIBA) in one chromatographic cluster, and two isomers (α-AIBA (AAIBA) and d-BABA) in a second cluster. Partially separated cluster components were deconvoluted using Gaussian peak fitting except for GABA and d-BAIBA. MS/MS detection of Marfey's derivatized ABA isomers provided six MS/MS fragments, with substantially different intensity profiles between structural isomers. This allowed linear deconvolution of ABA isomer peaks. Combining HPLC separation with linear and Gaussian deconvolution allowed resolution of all eight ABA isomers. Application to human serum found a substantial level of l-AABA (13 μM), an intermediate level of l-BAIBA (0.8 μM), and low but detectable levels (<0.2 μM) of GABA, l-BABA, AAIBA, d-BAIBA, and d-AABA. This approach should be useful for LC-MS/MS deconvolution of other challenging groups of isomeric molecules.
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Affiliation(s)
- Harika Vemula
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 2464 Charlotte Street, Kansas City, MO 64108, USA
| | - Yukiko Kitase
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 2464 Charlotte Street, Kansas City, MO 64108, USA
| | - Navid J Ayon
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 2464 Charlotte Street, Kansas City, MO 64108, USA
| | - Lynda Bonewald
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 2464 Charlotte Street, Kansas City, MO 64108, USA
| | - William G Gutheil
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 2464 Charlotte Street, Kansas City, MO 64108, USA.
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Jayakody T, Marwari S, Lakshminarayanan R, Tan FCK, Johannes CW, Dymock BW, Poulsen A, Herr DR, Dawe GS. Hydrocarbon stapled B chain analogues of relaxin-3 retain biological activity. Peptides 2016; 84:44-57. [PMID: 27498038 DOI: 10.1016/j.peptides.2016.08.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 07/29/2016] [Accepted: 08/02/2016] [Indexed: 11/30/2022]
Abstract
Relaxin-3 or insulin-like peptide 7 (INSL7) is the most recently discovered relaxin/insulin-like family peptide. Mature relaxin-3 consists of an A chain and a B chain held by disulphide bonds. According to structure activity relationship studies, the relaxin-3 B chain is more important in binding and activating the receptor. RXFP3 (also known as Relaxin-3 receptor 1, GPCR 135, somatostatin- and angiotensin- like peptide receptor or SALPR) was identified as the cognate receptor for relaxin-3 by expression profiles and binding studies. Recent studies imply roles of this system in mediating stress and anxiety, feeding, metabolism and cognition. Stapling of peptides is a technique used to develop peptide drugs for otherwise undruggable targets. The main advantages of stapling include, increased activity due to reduced proteolysis, increased affinity to receptors and increased cell permeability. Stable agonists and antagonists of RXFP3 are crucial for understanding the physiological significance of this system. So far, agonists and antagonists of RXFP3 are peptides. In this study, for the first time, we have introduced stapling of the relaxin-3 B chain at 14th and 18th positions (14s18) and 18th and 22nd position (18s22). These stapled peptides showed greater helicity than the unstapled relaxin-3 B chain in circular dichroism analysis. Both stapled peptides bound RXFP3 and activated RXFP3 as observed in an inhibition of forskolin-induced cAMP assay and a ERK1/2 activation assay, although with different potencies. Therefore, we conclude that stapling of the relaxin3 B chain does not compromise its ability to activate RXFP3 and is a promising method for developing stable peptide agonists and antagonists of RXFP3 to aid relaxin-3/RXFP3 research.
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Affiliation(s)
- Tharindunee Jayakody
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Neurobiology and Ageing Programme, Life Sciences Institute, National University of Singapore, Singapore; Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore, Singapore
| | - Subhi Marwari
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore
| | - Rajamani Lakshminarayanan
- Singapore Eye Research Institute, Singapore; Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore
| | - Francis Chee Kuan Tan
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Charles William Johannes
- Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Brian William Dymock
- Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore
| | - Anders Poulsen
- Department of Medicinal Chemistry, Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Deron Raymond Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Gavin Stewart Dawe
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Neurobiology and Ageing Programme, Life Sciences Institute, National University of Singapore, Singapore; Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore, Singapore.
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12
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Gooding M, Malhotra M, Evans JC, Darcy R, O'Driscoll CM. Oligonucleotide conjugates - Candidates for gene silencing therapeutics. Eur J Pharm Biopharm 2016; 107:321-40. [PMID: 27521696 DOI: 10.1016/j.ejpb.2016.07.024] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 07/24/2016] [Accepted: 07/25/2016] [Indexed: 11/18/2022]
Abstract
The potential therapeutic and diagnostic applications of oligonucleotides (ONs) have attracted great attention in recent years. The capability of ONs to selectively inhibit target genes through antisense and RNA interference mechanisms, without causing un-intended sideeffects has led them to be investigated for various biomedical applications, especially for the treatment of viral diseases and cancer. In recent years, many researchers have focused on enhancing the stability and target specificity of ONs by encapsulating/complexing them with polymers or lipid chains to formulate nanoparticles/nanocomplexes/micelles. Also, chemical modification of nucleic acids has emerged as an alternative to impart stability to ONs against nucleases and other degrading enzymes and proteins found in blood. In addition to chemically modifying the nucleic acids directly, another strategy that has emerged, involves conjugating polymers/peptide/aptamers/antibodies/proteins, preferably to the sense strand (3'end) of siRNAs. Conjugation to the siRNA not only enhances the stability and targeting specificity of the siRNA, but also allows for the development of self-administering siRNA formulations, with a much smaller size than what is usually observed for nanoparticle (∼200nm). This review concentrates mainly on approaches and studies involving ON-conjugates for biomedical applications.
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Affiliation(s)
- Matt Gooding
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
| | - Meenakshi Malhotra
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
| | - James C Evans
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
| | - Raphael Darcy
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
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Yamashita H, Demizu Y, Misawa T, Shoda T, Kurihara M. Synthesis of a bis-cationic α,α-disubstituted amino acid (9-amino-bispidine-9-carboxylic acid) and its effects on the conformational properties of peptides. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.02.076] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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