1
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Nijland M, Lefebvre SN, Thangaratnarajah C, Slotboom DJ. Bidirectional ATP-driven transport of cobalamin by the mycobacterial ABC transporter BacA. Nat Commun 2024; 15:2626. [PMID: 38521790 PMCID: PMC10960864 DOI: 10.1038/s41467-024-46917-1] [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: 10/13/2023] [Accepted: 03/13/2024] [Indexed: 03/25/2024] Open
Abstract
BacA is a mycobacterial ATP-binding cassette (ABC) transporter involved in the translocation of water-soluble compounds across the lipid bilayer. Whole-cell-based assays have shown that BacA imports cobalamin as well as unrelated hydrophilic compounds such as the antibiotic bleomycin and the antimicrobial peptide Bac7 into the cytoplasm. Surprisingly, there are indications that BacA also mediates the export of different antibacterial compounds, which is difficult to reconcile with the notion that ABC transporters generally operate in a strictly unidirectional manner. Here we resolve this conundrum by developing a fluorescence-based transport assay to monitor the transport of cobalamin across liposomal membranes. We find that BacA transports cobalamin in both the import and export direction. This highly unusual bidirectionality suggests that BacA is mechanistically distinct from other ABC transporters and facilitates ATP-driven diffusion, a function that may be important for the evolvability of specific transporters, and may bring competitive advantages to microbial communities.
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Affiliation(s)
- Mark Nijland
- Faculty of Science and Engineering, Groningen, Biomolecular Sciences and Biotechnology, Membrane Enzymology Group, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - Solène N Lefebvre
- Faculty of Science and Engineering, Groningen, Biomolecular Sciences and Biotechnology, Membrane Enzymology Group, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - Chancievan Thangaratnarajah
- Faculty of Science and Engineering, Groningen, Biomolecular Sciences and Biotechnology, Membrane Enzymology Group, University of Groningen, 9747 AG, Groningen, The Netherlands
- Sosei Heptares, Steinmetz Building, Granta Park, Great Abington, Cambridge, CB21 6DG, UK
| | - Dirk J Slotboom
- Faculty of Science and Engineering, Groningen, Biomolecular Sciences and Biotechnology, Membrane Enzymology Group, University of Groningen, 9747 AG, Groningen, The Netherlands.
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2
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Liles A, Cham N, Opp ML, Tinsley IC, Chepurny OG, Holz GG, Doyle RP. Corrination mitigates peptide aggregation as exemplified for Glucagon. Peptides 2024; 171:171134. [PMID: 38092266 PMCID: PMC10842878 DOI: 10.1016/j.peptides.2023.171134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 12/18/2023]
Abstract
Pharmaceutical development of glucagon for use in acute hypoglycemia has proved challenging, due in large part to poor solubility, poor stability and aggregate formation. Herein, we describe highly soluble, low aggregating, glucagon conjugates generated through use of the commercially available vitamin B12 precursor dicyanocobinamide ('corrination'), which retain full stimulatory action at the human glucagon receptor. The modified glucagon analogs were tested in a chemical stability assay in 50 mM phosphate buffer and the percentage of original concentration retained was determined after two weeks of incubation at 37° C. Aggregate formation assays were also performed after 48 h of agitation at 37°C using a thioflavin (ThT) fluorescence-based assay. All corrinated compounds retained original concentration to a higher degree than glucagon controls and showed markedly decreased aggregation compared to their respective noncorrinated analogues. Based on the statistically significant increase in chemical stability coupled with the notably decreased tendency to form aggregates, analogues 2 and its corrinated conjugate 5 were used for a functional assay study performed after agitation at 37°C for 24-hr after which agonism was measured at the human glucagon receptor using a cAMP FRET assay. Corrinated 5 exhibited a 6.6-fold increased potency relative to glucagon, which was shown to have a 165-fold reduction in potency. The relative potency of 5 was also improved compared to that of 2 with EC50 values of 5.5 nM and 9.6 nM for 5 and 2, respectively. In conclusion, corrination of peptides mitigates aggregation, presenting a compound with prolonged stability and agonism as demonstrated for glucagon.
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Affiliation(s)
- Amber Liles
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States
| | - Nancy Cham
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States
| | - Morgan L Opp
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States
| | - Ian C Tinsley
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States
| | - Oleg G Chepurny
- Department of Medicine, State University of New York, Upstate Medical University, Syracuse, NY 13210, United States
| | - George G Holz
- Department of Medicine, State University of New York, Upstate Medical University, Syracuse, NY 13210, United States; Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, NY 13210, United States
| | - Robert P Doyle
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States; Department of Medicine, State University of New York, Upstate Medical University, Syracuse, NY 13210, United States; Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, NY 13210, United States.
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3
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Singh S, Pal S. Synthesis of benzimidazole fused poly-heterocycles via oxidant free Cu-catalyzed dehydrogenative C-N coupling and photophysical studies. Chem Commun (Camb) 2023; 59:13498-13501. [PMID: 37882367 DOI: 10.1039/d3cc03931e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
A unique example of Cu-catalysed synthesis of benzimidazole fused poly-heterocycles via intramolecular C-N coupling reaction has been reported. The method highlights the potential of Cu-catalysed reactions via C-N bond formation in the absence of ligand, oxidant, and additives under inert atmosphere. The mechanistic studies indicate that the reaction is facilitated by the involvement of a benzimidazole N-atom and releases H2 gas, resulting in the synthesis of benzimidazole-fused coupling products in good yield. The versatility of the approach is demonstrated by the synthesis of diverse fused compounds, which exhibit high fluorescence activity and good quantum yield.
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Affiliation(s)
- Sakshi Singh
- School of Basic Sciences (Chemistry), Indian Institute of Technology Bhubaneswar, Argul, Khordha-752050, Odisha, India.
| | - Shantanu Pal
- School of Basic Sciences (Chemistry), Indian Institute of Technology Bhubaneswar, Argul, Khordha-752050, Odisha, India.
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4
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Shichijo K, Kametani Y, Shiota Y, Yoshizawa K, Fujitsuka M, Shimakoshi H. Effect of Macrocycles on the Photochemical and Electrochemical Properties of Cobalt-Dehydrocorrin Complex: Formation and Investigation of Co(I) Species. Inorg Chem 2023; 62:11785-11795. [PMID: 37307067 DOI: 10.1021/acs.inorgchem.3c00882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Co(II)-pyrocobester (P-Co(II)), a dehydrocorrin complex, was semisynthesized from vitamin B12 (cyanocobalamin), and its photochemical and electrochemical properties were investigated and compared to those of the cobester (C-Co(II)), the cobalt-corrin complex. The UV-vis absorptions of P-Co(II) in CH2Cl2, ascribed to the π-π* transition, were red-shifted compared to those of C-Co(II) due to the π-expansion of the macrocycle in the pyrocobester. The reversible redox couple of P-Co(II) was observed at E1/2 = -0.30 V vs Ag/AgCl in CH3CN, which was assigned to the Co(II)/Co(I) redox couple by UV-vis, ESR, and molecular orbital analysis. This redox couple was positively shifted by 0.28 V compared to that of C-Co(II). This is caused by the high electronegativity of the dehydrocorrin macrocycle, which was estimated by DFT calculations for the free-base ligands. The reactivity of the Co(I)-pyrocobester (P-Co(I)) was evaluated by the reaction with methyl iodide in CV and UV-vis to form a photosensitive Co(III)-CH3 complex (P-Co(III)-CH3). The properties of the excited state of P-Co(I), *Co(I), were also investigated by femtosecond transient absorption (TA) spectroscopy. The lifetime of *Co(I) was estimated to be 29 ps from the kinetic trace at 587 nm. The lifetime of *Co(I) became shorter in the presence of Ar-X, such as iodobenzonitrile (1a), bromobenzonitrile (1b), and chlorobenzonitrile (1c), and the rate constants of electron transfer (ET) between the *Co(I) and Ar-X were determined to be 2.9 × 1011 M-1 s-1, 4.9 × 1010 M-1 s-1, and 1.0 × 1010 M-1 s-1 for 1a, 1b, and 1c, respectively.
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Affiliation(s)
- Keita Shichijo
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Nishi-ku, Motooka, 744, Fukuoka 819-0395, Japan
| | - Yohei Kametani
- Institute for Materials Chemistry and Engineering, Kyushu University, Nishi-ku, Motooka, 744, Fukuoka 819-0395, Japan
| | - Yoshihito Shiota
- Institute for Materials Chemistry and Engineering, Kyushu University, Nishi-ku, Motooka, 744, Fukuoka 819-0395, Japan
| | - Kazunari Yoshizawa
- Institute for Materials Chemistry and Engineering, Kyushu University, Nishi-ku, Motooka, 744, Fukuoka 819-0395, Japan
| | - Mamoru Fujitsuka
- SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Osaka 567-0047, Japan
| | - Hisashi Shimakoshi
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Nishi-ku, Motooka, 744, Fukuoka 819-0395, Japan
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5
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Machalska E, Zajac G, Wierzba AJ, Kapitán J, Andruniów T, Spiegel M, Gryko D, Bouř P, Baranska M. Recognition of the True and False Resonance Raman Optical Activity. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ewa Machalska
- Faculty of Chemistry Jagiellonian University Gronostajowa 2 30-387 Krakow Poland
- Jagiellonian Centre for Experimental Therapeutics (JCET) Jagiellonian University Bobrzynskiego 14 30-348 Krakow Poland
| | - Grzegorz Zajac
- Jagiellonian Centre for Experimental Therapeutics (JCET) Jagiellonian University Bobrzynskiego 14 30-348 Krakow Poland
- Institute of Organic Chemistry and Biochemistry Academy of Sciences Flemingovo náměstí 2 16610 Prague Czech Republic
| | - Aleksandra J. Wierzba
- Institute of Organic Chemistry Polish Academy of Sciences Kasprzaka 44/52 01-224 Warsaw Poland
| | - Josef Kapitán
- Department of Optics Palacký University Olomouc 17. listopadu 12 77146 Olomouc Czech Republic
| | - Tadeusz Andruniów
- Department of Chemistry Wroclaw University of Science and Technology Wyb. Wyspianskiego 27 50-370 Wroclaw Poland
| | - Maciej Spiegel
- Department of Pharmacognosy and Herbal Medicine Wroclaw Medical University Borowska 211A 50-556 Wroclaw Poland
| | - Dorota Gryko
- Institute of Organic Chemistry Polish Academy of Sciences Kasprzaka 44/52 01-224 Warsaw Poland
| | - Petr Bouř
- Institute of Organic Chemistry and Biochemistry Academy of Sciences Flemingovo náměstí 2 16610 Prague Czech Republic
| | - Malgorzata Baranska
- Faculty of Chemistry Jagiellonian University Gronostajowa 2 30-387 Krakow Poland
- Jagiellonian Centre for Experimental Therapeutics (JCET) Jagiellonian University Bobrzynskiego 14 30-348 Krakow Poland
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6
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Machalska E, Zajac G, Wierzba AJ, Kapitán J, Andruniów T, Spiegel M, Gryko D, Bouř P, Baranska M. Recognition of the True and False Resonance Raman Optical Activity. Angew Chem Int Ed Engl 2021; 60:21205-21210. [PMID: 34216087 PMCID: PMC8519086 DOI: 10.1002/anie.202107600] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/01/2021] [Indexed: 12/16/2022]
Abstract
Resonance Raman optical activity (RROA) possesses all aspects of a sensitive tool for molecular detection, but its measurement remains challenging. We demonstrate that reliable recording of RROA of chiral colorful compounds is possible, but only after considering the effect of the electronic circular dichroism (ECD) on the ROA spectra induced by the dissolved chiral compound. We show RROA for a number of model vitamin B12 derivatives that are chemically similar but exhibit distinctively different spectroscopic behavior. The ECD/ROA effect is proportional to the concentration and dependent on the optical pathlength of the light propagating through the sample. It can severely alter relative band intensities and signs in the natural RROA spectra. The spectra analyses are supported by computational modeling based on density functional theory. Neglecting the ECD effect during ROA measurement can lead to misinterpretation of the recorded spectra and erroneous conclusions about the molecular structure.
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Affiliation(s)
- Ewa Machalska
- Faculty of ChemistryJagiellonian UniversityGronostajowa 230-387KrakowPoland
- Jagiellonian Centre for Experimental Therapeutics (JCET)Jagiellonian UniversityBobrzynskiego 1430-348KrakowPoland
| | - Grzegorz Zajac
- Jagiellonian Centre for Experimental Therapeutics (JCET)Jagiellonian UniversityBobrzynskiego 1430-348KrakowPoland
- Institute of Organic Chemistry and BiochemistryAcademy of SciencesFlemingovo náměstí 216610PragueCzech Republic
| | - Aleksandra J. Wierzba
- Institute of Organic ChemistryPolish Academy of SciencesKasprzaka 44/5201-224WarsawPoland
| | - Josef Kapitán
- Department of OpticsPalacký University Olomouc17. listopadu 1277146OlomoucCzech Republic
| | - Tadeusz Andruniów
- Department of ChemistryWroclaw University of Science and TechnologyWyb. Wyspianskiego 2750-370WroclawPoland
| | - Maciej Spiegel
- Department of Pharmacognosy and Herbal MedicineWroclaw Medical UniversityBorowska 211A50-556WroclawPoland
| | - Dorota Gryko
- Institute of Organic ChemistryPolish Academy of SciencesKasprzaka 44/5201-224WarsawPoland
| | - Petr Bouř
- Institute of Organic Chemistry and BiochemistryAcademy of SciencesFlemingovo náměstí 216610PragueCzech Republic
| | - Malgorzata Baranska
- Faculty of ChemistryJagiellonian UniversityGronostajowa 230-387KrakowPoland
- Jagiellonian Centre for Experimental Therapeutics (JCET)Jagiellonian UniversityBobrzynskiego 1430-348KrakowPoland
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7
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Jackowska A, Gryko D. Vitamin B 12 Derivatives Suitably Tailored for the Synthesis of Photolabile Conjugates. Org Lett 2021; 23:4940-4944. [PMID: 33794095 DOI: 10.1021/acs.orglett.1c00839] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Vitamin B12 conjugates are broadly studied in biological sciences. As light offers spatiotemporal control, we decided to develop a method for the preparation of vitamin B12 conjugates that release tethered molecules upon exposure to light. Herein, we report vitamin B12 derivatives possessing a photolabile linker suitable for conjugation with amines, azides, and alkynes. The potential applications of such conjugates are broad and include the delivery of drugs, labels, and imaging agents to their place of action and spatiotemporal release.
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Affiliation(s)
- Agnieszka Jackowska
- Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Dorota Gryko
- Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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8
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Potrząsaj A, Musiejuk M, Chaładaj W, Giedyk M, Gryko D. Cobalt Catalyst Determines Regioselectivity in Ring Opening of Epoxides with Aryl Halides. J Am Chem Soc 2021; 143:9368-9376. [PMID: 34081860 PMCID: PMC8297733 DOI: 10.1021/jacs.1c00659] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Ring-opening of epoxides
furnishing either linear or branched products
belongs to the group of classic transformations in organic synthesis.
However, the regioselective cross-electrophile coupling of aryl epoxides
with aryl halides still represents a key challenge. Herein, we report
that the vitamin B12/Ni dual-catalytic system allows for
the selective synthesis of linear products under blue-light irradiation,
thus complementing methodologies that give access to branched alcohols.
Experimental and theoretical studies corroborate the proposed mechanism
involving alkylcobalamin as an intermediate in this reaction.
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Affiliation(s)
- Aleksandra Potrząsaj
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Mateusz Musiejuk
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Wojciech Chaładaj
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Maciej Giedyk
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Dorota Gryko
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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9
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Abstract
The recently delineated structure- and reactivity-based concept of antivitamins B12 has begun to bear fruit by the generation, and study, of a range of such B12 -dummies, either vitamin B12 -derived, or transition metal analogues that also represent potential antivitamins B12 or specific B12 -antimetabolites. As reviewed here, this has opened up new research avenues in organometallic B12 -chemistry and bioinorganic coordination chemistry. Exploratory studies with antivitamins B12 have, furthermore, revealed some of their potential, as pharmacologically interesting compounds, for inducing B12 -deficiency in a range of organisms, from hospital resistant bacteria to laboratory mice. The derived capacity of antivitamins B12 to induce functional B12 -deficiency in mammalian cells and organs also suggest their valuable potential as growth inhibitors of cancerous human and animal cells.
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Affiliation(s)
- Bernhard Kräutler
- Institute of Organic Chemistry and Center for Molecular Biosciences (CMBI)University of Innsbruck6020InnsbruckAustria
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10
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Cu-catalyzed click conjugation of cobalamin to a BODIPY-based fluorophore: A versatile tool to explore the cellular biology of vitamin B 12. J Inorg Biochem 2020; 210:111105. [PMID: 32763615 DOI: 10.1016/j.jinorgbio.2020.111105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 05/06/2020] [Accepted: 05/07/2020] [Indexed: 11/21/2022]
Abstract
The Cu-catalyzed click conjugation of an azide-functionalized vitamin B12 (cobalamin) and an alkyne-labeled 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) led to the formation of a highly stable fluorescent BODIPY-labeled vitamin B12 (λex/λem = 495/508 nm). The formation of what has been identified as an iodine adduct of the conjugate was also observed as a side-product during this reaction and could be removed using HPLC. BODIPY-labeled vitamin B12 was characterized by NMR and HR-ESI-MS. In vitro studies on wild-type human fibroblasts indicated that BODIPY-labeled vitamin B12 could internalize in a manner similar to that of untagged vitamin B12. ATP-binding cassette sub-family D member 4 (ABCD4) is a lysosomal localized transporter required to export vitamin B12 from the lysosomal lumen to the cytosol. Mutations in this transporter result in the accumulation of vitamin B12 in lysosomes. In human fibroblasts harbouring a mutation in ABCD4, BODIPY-labeled vitamin B12 accumulated in the lumen of lysosomes. Our data suggests the potential use of BODIPY-labeled vitamin B12 to investigate the intracellular behavior of the vitamin in the context of disorders related to the abnormal cellular utilization of the vitamin. Moreover, results presented here demonstrate that click chemistry could be exploited for the conjugation of vitamin B12 to various other fluorophores.
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11
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Zhao S, Wang ZP, Wen X, Li S, Wei G, Guo J, He Y. Synthesis of Vitamin B 12-Antibiotic Conjugates with Greatly Improved Activity against Gram-Negative Bacteria. Org Lett 2020; 22:6632-6636. [PMID: 32806210 DOI: 10.1021/acs.orglett.0c02403] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
There is an urgent need to discover new antibiotics and improve the efficacy of known antibiotics against Gram-negative bacteria. "Trojan horse" conjugates are novel and promising antibiotics. Herein we report the design and synthesis of vitamin-B12-ampicillin conjugates, which exhibited more than 500 times improved activity against Escherichia coli compared with ampicillin itself. Our studies demonstrate that the vitamin-B12 uptake pathway could be employed for effective antibiotic delivery and efficacy enhancement.
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Affiliation(s)
- Sheng Zhao
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P.R. China
| | - Zhi-Peng Wang
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Xumei Wen
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P.R. China
| | - Siyu Li
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P.R. China
| | - Guoxing Wei
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P.R. China
| | - Jian Guo
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P.R. China
| | - Yun He
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P.R. China
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