Article
Biochemistry & Molecular Biology
Sirine Jaber, Veronica Nemska, Ivan Iliev, Elena Ivanova, Tsvetelina Foteva, Nelly Georgieva, Ivan Givechev, Emilia Naydenova, Veronika Karadjova, Dancho Danalev
Summary: The synthesized conjugates showed selective index against MCF-7 tumor cells, good antifungal properties, and good hydrolytic stability. Additionally, the compound containing β-Ala exhibited good antimicrobial activity against Escherichia coli and Bacillus subtilis.
Article
Biochemistry & Molecular Biology
Yaxian Lin, Yangyang Jiang, Ziwei Zhao, Yueyang Lu, Xinping Xi, Chengbang Ma, Xiaoling Chen, Mei Zhou, Tianbao Chen, Chris Shaw, Lei Wang
Summary: Temporin-PKE is a novel peptide extracted from the skin secretion of Pelophylax kl. esculentus, which displays strong antimicrobial activity and cytotoxicity. Strategies for modifications include incorporating positively charged residues, D-amino acids, and altering the side chain amino acids. The optimal analogue, Temporin-PKE-3K, exhibits dual efficient functions, strong antimicrobial and anticancer activity.
Article
Chemistry, Organic
Samantha A. Murphy, Caroline Phelan, Sankarasekaran Shanmugaraju, Salvador Blasco, Thorfinnur Gunnlaugsson
Summary: The synthesis of compounds with 3-amino-1,8-naphthalimide Troger's base's (TBNaps) possessing multiple amino acids at the imide terminus is described. The solid-state X-ray crystal structure and supramolecular packing of one derivative are outlined. The molecules display Internal Charge Transfer (ICT) excited state properties and show potential as beta-turn mimics for peptide and polypeptide structures.
TETRAHEDRON LETTERS
(2021)
Article
Infectious Diseases
Maria Veronica Humpola, Roque Spinelli, Melina Erben, Virginia Perdomo, Georgina Guadalupe Tonarelli, Fernando Albericio, Alvaro Sebastian Siano
Summary: In this study, analogs of two antimicrobial peptides, C10:0-A2 and TA4, were designed and synthesized, and non-proteinogenic amino acids were used to improve their therapeutic properties. The physicochemical properties and antimicrobial activity of these analogs were analyzed. The results showed that substitution with D- and N-methyl amino acids could enhance stability against enzymatic degradation and modulate the therapeutic properties of antimicrobial peptides and lipopeptides. The study provides insights into the design and optimization of antimicrobial peptides for improved stability and therapeutic efficacy. TA4(dK), C10:0-A2(6-NMeLys), and C10:0-A2(9-NMeLys) were identified as the most promising molecules for further studies.
Article
Infectious Diseases
Xiaoou Zhao, Mengna Zhang, Inam Muhammad, Qi Cui, Haipeng Zhang, Yu Jia, Qijun Xu, Lingcong Kong, Hongxia Ma
Summary: The designed peptide OM19D, obtained by replacing the amino acid residues at trypsin cleavage sites with d-amino acid residues, not only maintained antibacterial activity but also enhanced stability against trypsin. This strategy is beneficial for improving the protease stability of antibacterial peptides, showing high antibacterial activity even under high concentrations of trypsin treatment.
Article
Biochemistry & Molecular Biology
Yu-Huan Cheah, Chun-Yu Liu, Bak-Sau Yip, Chih-Lung Wu, Kuang-Li Peng, Jya-Wei Cheng
Summary: The study found that the newly developed peptide Nal-P-113 showed the best anticancer activity and induced cancer cells to release potent danger-associated molecular patterns (DAMPs), which could help in developing better antimicrobial peptides for therapeutic applications.
Article
Multidisciplinary Sciences
Kai-Yao Huang, Yi-Jhan Tseng, Hui-Ju Kao, Chia-Hung Chen, Hsiao-Hsiang Yang, Shun-Long Weng
Summary: A two-step machine learning model was developed to effectively identify subtypes of anticancer peptides by examining amino acid composition and physicochemical properties. The model demonstrated high accuracy and specificity in cross-validation and independent testing, indicating its predictive power. The hybrid feature sets considered in the training process contributed to the model's effectiveness in discriminating between ACPs and non-ACPs.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Organic
Jose A. C. Delgado, Jose T. M. Correia, Emanuele F. Pissinati, Marcio W. Paixao
Summary: This technology utilizes alkyl radicals to selectively alkylate dehydroalanine, offering a convenient method for the synthesis of unnatural amino acids and late-stage functionalization of pharmaceuticals.
Article
Chemistry, Multidisciplinary
Yiyin Xia, Janet To, Ning-Yu Chan, Side Hu, Heng Tai Liew, Seetharamsing Balamkundu, Xiaohong Zhang, Julien Lescar, Surajit Bhattacharjya, James P. Tam, Chuan-Fa Liu
Summary: This study found that Asn(OH) is an unnatural substrate for PALs, and successfully synthesized a new MMP2 inhibitor cyclic peptide using Asn(OH)-mediated cyclization, with the hydroxamic acid moiety as the key pharmacophore. Several bioactive Asp-containing cyclic peptides were also synthesized using this approach, demonstrating the effectiveness of substrate engineering in expanding the application of PAL ligation in the synthesis of therapeutic cyclic peptides.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Marco Campanile, Rosario Oliva, Pompea Del Vecchio, Roland Winter, Luigi Petraccone
Summary: LL-III, a natural anticancer peptide, has been found to bind to G-quadruplex structures with high affinity, which are known to be important targets in anticancer treatment.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Applied
Alemayehu Gashaw Woldegiorgis, Zhao Han, Xufeng Lin
Summary: An enantioselective synthesis of unnatural pyrazole-based alpha-chiral amino acid derivatives was developed using a chiral spirocyclic phosphoric acid catalyst, with yields ranging from 67-98% and enantioselectivities of 73-99%. The NH2 functionality in the products enables further transformations to a chiral thiourea and a lactam, providing a versatile synthetic route for obtaining tetrasubstituted carbon stereocenters in pyrazole-based alpha-amino acid derivatives.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Laura Sinatra, Lisa Kolano, Maik Icker, Stefan R. Fritzsche, Daniela Volke, Ines Gockel, Rene Thieme, Ralf Hoffmann, Finn K. Hansen
Summary: alpha-aminoxy peptides are a group of peptidomimetics with high proteolytic stability and the ability to fold into specific and predictable secondary structures. This study synthesized a series of hybrid peptides composed of alpha-aminoxy acids and alpha-amino acids with alternating cationic and aromatic, hydrophobic side chains, showing significant impact of peptide chain length and N-terminal cap on their antimicrobial and anticancer properties. Peptide 6e with Fmoc-capping showed the most potent antimicrobial activity against Gram-negative and Gram-positive bacterial strains.
Article
Chemistry, Multidisciplinary
Yujun Li, Jie Yang, Xinxin Geng, Pan Tao, Yanling Shen, Zhishan Su, Ke Zheng
Summary: This article presents a single-step radical approach for the modular synthesis of functionally diverse alpha-tertiary amino acids (ATAAs). The synthesis takes place under mild conditions without the use of metals, photocatalysts, or other additives. The method demonstrates broad functional group tolerance and late-stage applicability, as well as gram-scale synthesis via flow chemistry. Mechanistic studies reveal the key intermediate in the reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Biochemical Research Methods
Piyush Agrawal, Dhruv Bhagat, Manish Mahalwal, Neelam Sharma, Gajendra P. S. Raghava
Summary: The study developed a computational model for predicting and designing anticancer peptides (ACPs), revealing residue composition preference, positional preference, and motif features of ACPs. Machine learning models were utilized and trained on different datasets, with the best models implemented on the webserver AntiCP 2.0 for free access.
BRIEFINGS IN BIOINFORMATICS
(2021)
Article
Biotechnology & Applied Microbiology
Sirine Jaber, Veronica Nemska, Ivan Iliev, Elena Ivanova, Tsvetelina Foteva, Nelly Georgieva, Ivan Givechev, Dimiter Tanev, Emilia Naydenova, Dancho Danalev
Summary: Peptides are a promising alternative to conventional medical drugs due to their natural mechanisms for elimination, resulting in minimal side effects. The synthesis and studies of the antimicrobial peptide (KLAKLAK)(2)-NH2, with a modified amino acid nor-Leu, and the addition of a proven anticancer agent, were reported. Results showed that the hybrid structure 1,8-NphtG-(KNleAKNleAK)(2)-NH2 exhibited enhanced antiproliferative properties and antimicrobial activity, making it a potential medical drug for treating mammary gland type A adenocarcinoma (MCF-7) with antimicrobial properties.
BIOTECHNOLOGY & BIOTECHNOLOGICAL EQUIPMENT
(2023)
Article
Oncology
Anelia Ts Mavrova, Stefan Dimov, Denitsa Yancheva, Miroslav Rangelov, Diana Wesselinova, Emilia Naydenova
Summary: The aim of this study was to develop and explore a new series of cytotoxic agents based on the conjugation between the thieno[2,3-d]pyrimidine moiety and a second pharmacophore at the C2 or N3 position. The results showed that some of the thieno[2,3-d]pyrimidine derivatives exhibited improved EGFR inhibitory activity. Additionally, the benzimidazole derivatives showed anticancer activity. In vitro tests demonstrated that these thieno[2,3-d]pyrimidines exhibited cytotoxicity against cancer cells at nanomolar concentrations and low toxicity against normal cells.
ANTI-CANCER AGENTS IN MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Pragti, Bidyut Kumar Kundu, Shrish Nath Upadhyay, Nilima Sinha, Rakesh Ganguly, Ivo Grabchev, Srimanta Pakhira, Suman Mukhopadhyay
Summary: In this study, four organometallic Ru(II)-arene complexes were designed and synthesized, and it was found that they possess anticancer, antimetastatic, and two-photon cell imaging abilities. These complexes also demonstrate good catalytic activity in the transfer hydrogenation reaction and strong interactions with biological molecules and DNA. Furthermore, the complexes show capabilities to inhibit cell migration and generate intracellular reactive oxygen species in breast cancer cells.
DALTON TRANSACTIONS
(2022)
Article
Biochemistry & Molecular Biology
Lyubomir T. Vezenkov, Dancho L. Danalev, Iwan Iwanov, Valentin Lozanov, Atanas Atanasov, Rumyana Todorova, Nikolay Vassilev, Veronika Karadjova
Summary: Alzheimer's disease is a neurodegenerative disorder that negatively affects millions of people worldwide. The treatment for this disease remains difficult and incomplete. In this study, new derivatives of galanthamine were designed and synthesized, and their beta-secretase inhibitory activity and anti-aggregating effect were investigated. The results showed that five of the new compounds exhibited high beta-secretase inhibitory activity, and four compounds were able to effectively inhibit platelet aggregation.
Article
Biochemistry & Molecular Biology
Dancho Danalev, Ivan Iliev, Dessislava Borisova, Tatyana Dzimbova, Tamara Pajpanova, Zdravka Zaharieva, Veronika Karadjova, Tsvetelina Foteva, Emilia Naydenova
Summary: This study reports the synthesis, biological evaluation, mathematical docking calculations, and hydrolytic stability of new bioconjugates, aiming to find new drugs for cancer treatment. The results indicate that one of the compounds shows good selectivity and stability, making it the best candidate for practical application.
PROTEIN AND PEPTIDE LETTERS
(2022)
Article
Multidisciplinary Sciences
Victoria Vitkova, Angelina Stoyanova-Ivanova, Sirine Jaber, Emilia Naydenova, Dancho Danalev
Summary: This study investigates the interaction between antimicrobial peptide KLAKLAK-NH2 and membranes, finding that bilayer stacking formation occurs under specific conditions. Additionally, peripheral peptide orientation on lipid bilayers may be a prerequisite for channel formation. Evaluating the peptide partition coefficient could assist in further refining the pharmacokinetic properties of antimicrobial peptides.
COMPTES RENDUS DE L ACADEMIE BULGARE DES SCIENCES
(2022)
Article
Biotechnology & Applied Microbiology
Sirine Jaber, Veronica Nemska, Ivan Iliev, Elena Ivanova, Tsvetelina Foteva, Nelly Georgieva, Ivan Givechev, Dimiter Tanev, Emilia Naydenova, Dancho Danalev
Summary: Peptides are a promising alternative to conventional medical drugs due to their natural mechanisms for elimination, resulting in minimal side effects. The synthesis and studies of the antimicrobial peptide (KLAKLAK)(2)-NH2, with a modified amino acid nor-Leu, and the addition of a proven anticancer agent, were reported. Results showed that the hybrid structure 1,8-NphtG-(KNleAKNleAK)(2)-NH2 exhibited enhanced antiproliferative properties and antimicrobial activity, making it a potential medical drug for treating mammary gland type A adenocarcinoma (MCF-7) with antimicrobial properties.
BIOTECHNOLOGY & BIOTECHNOLOGICAL EQUIPMENT
(2023)
Article
Chemistry, Analytical
Awad I. Said, Desislava Staneva, Silvia Angelova, Ivo Grabchev
Summary: A novel diamino triazine based 1,8-naphthalimide (NI-DAT) was synthesized and its photophysical properties were investigated. The fluorescence emission of NI-DAT was greatly affected by solvent polarity and quenched at higher pH due to photo-induced electron transfer. The chemosensor showed good selectivity and sensitivity towards Hg2+ in the presence of other cations and anions. Job's plot revealed a stoichiometric ratio of 2:1 for NI-DAT/Hg2+ complex.
Article
Chemistry, Physical
Albena Bachvarova-Nedelcheva, Reni Iordanova, Anton Naydenov, Angelina Stoyanova, Nelly Georgieva, Veronica Nemska, Tsvetelina Foteva
Summary: TiO2/TeO2 powders were synthesized via sol-gel method using telluric acid (H6TeO6) and titanium butoxide as precursors. The as-prepared gel was heated in the temperature range of 200-700 degrees C and characterized by XRD, IR, UV-Vis analysis, and SEM. Depending on the heating temperature, the final products were identified as mixtures containing TiO2 (anatase), alpha-TeO2 (paratellurite), and TiTe3O8. The gels exhibited thermal stability and transformation from organic-inorganic amorphous phase to inorganic phase at higher temperatures. The photodegradation efficiency of the TiO2/TeO2 samples towards Malachite green dye and its antimicrobial activity against E. coli K12 were evaluated. Furthermore, the material showed promising potential as an active phase in environmental catalysts through catalytic oxidation reactions.
Article
Chemistry, Inorganic & Nuclear
Ivo Grabchev, Silvia Angelova, Desislava Staneva
Summary: Two new 1,8-naphthalimides with different substituents at the C-4 position have been synthesized and characterized. Their photophysical properties were investigated in organic solvents of different polarities, and their ability to detect metal ions in DMF solution was studied. The nature of the C-4 substituents affected the optical and metal ion sensing properties of the compounds. Theoretical calculations using DFT and TDDFT methods were also performed to analyze their geometric and electronic structures.
Article
Chemistry, Analytical
Awad I. I. Said, Desislava Staneva, Ivo Grabchev
Summary: A new water-soluble poly(propylene imine) dendrimer (PPI) modified with 4-sulfo-1,8-naphthalimide units (SNID) and its related structure monomer analog (SNIM) were synthesized. The fluorescence emission of the aqueous solution of SNIM or SNID was affected by various organic solvents, with detection limits below 0.05% (v/v). SNID demonstrated the ability to mimic XNOR and INHIBIT logic gates based on molecular size, using water and ethanol as inputs and AIE/excimer emissions as outputs.
Article
Pharmacology & Pharmacy
Dancho Danalev, Ivan Iliev, Stefan Dobrev, Silvia Angelova, Stoiko Petrin, Tatyana Dzimbova, Elena Ivanova, Dessislava Borisova, Emilia Naydenova
Summary: By synthesizing and testing a series of analogs, researchers found that compound D-Phe-Phe-Phe-D-Trp-Lys-Thr-Tyr(7)-Thr-NH2 (DD8), with one phenylalanine residue replaced by tyrosine in D-Phe-Phe-Phe-D-Trp-Lys-Thr-Phe-Thr-NH2 (BIM-23052), exhibited the best inhibitory effect on cancer cell proliferation and the highest lipophilicity.
Article
Engineering, Biomedical
Stela Georgieva, Petar Todorov, Desislava Staneva, Petar Grozdanov, Ivanka Nikolova, Ivo Grabchev
Summary: This study quantified the effect of peptide ligand on the complexing properties of Cu(II) ion and investigated the formation of copper complexes with hemorphin peptide motifs in alkalic water solutions. Analytical techniques including voltammetry, UV-Vis, fluorimetry, IR spectroscopy, and EPR were used to characterize the resulting complexes. The possible synergistic action of copper ions in antivirus protection processes of cotton fibers was also examined. The obtained results can facilitate future biological studies on structure-activity relationships.
JOURNAL OF FUNCTIONAL BIOMATERIALS
(2023)
Article
Chemistry, Inorganic & Nuclear
Pragti, Sreshtha Nayek, Satyam Singh, Avinash Sonawane, Ivo Grabchev, Rakesh Ganguly, Suman Mukhopadhyay
Summary: In this study, three Ru(II) arene complexes with a bidentate benzimidazole-based ligand were synthesized and their antitumor activity was studied by varying the co-ligand X. The synthesized compounds showed good interactions with serum albumin proteins, had good drug stability and lipophilic character. They were found to bind with DNA and could induce apoptosis in cancer cells, as well as upregulate cleaved caspase-3 expression and downregulate BCLXL expression. These findings provide a new direction for the investigation of antitumor ruthenium-based metallodrugs using benzimidazole-based ligands.
DALTON TRANSACTIONS
(2023)