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Hyun-Jung Sung, Kyung-Hyun Kim, Young-In Maeng, Kwan-Kyu Park
No abstract text is available yet for this article.
February 2016: Pathology
Sanad Alonezi, Jonans Tusiimire, Jennifer Wallace, Mark J Dufton, John A Parkinson, Louise C Young, Carol J Clements, Jin Kyu Park, Jong Woon Jeon, Valerie A Ferro, David G Watson
In the present study, liquid chromatography-mass spectrometry (LC-MS) was employed to characterise the metabolic profiles of two human ovarian cancer cell lines A2780 (cisplatin-sensitive) and A2780CR (cisplatin-resistant) in response to their exposure to melittin, a cytotoxic peptide from bee venom. In addition, the metabolomics data were supported by application of Biolog microarray technology to examine the utilisation of carbon sources by the two cell lines. Data extraction with MZmine 2.14 and database searching were applied to provide metabolite lists...
October 13, 2016: Metabolites
Lucia Becucci, Giovanni Aloisi, Rolando Guidelli
Melittin exhibits an ohmic behavior in a lipid bilayer having a DOPC distal leaflet and interposed between a 2.25nm tetraethyleneoxy chain tethered to a mercury drop and an aqueous solution. This behavior is induced in a pH6.8 buffer solution of 0.8μg/mL melittin by a pretreatment consisting of series of electrochemical impedance spectroscopy measurements at bias potentials varied by 50mV steps over a transmembrane potential range from about +250 to -250mV. This metastable ohmic behavior remains unchanged for hours, even after acidifying the solution to pH3...
October 6, 2016: Bioelectrochemistry
Mija Ahn, Pethaiah Gunasekaran, Ganesan Rajasekaran, Eun Young Kim, Soo-Jae Lee, Geul Bang, Kun Cho, Jae-Kyung Hyun, Hyun-Ju Lee, Young Ho Jeon, Nam-Hyung Kim, Eun Kyoung Ryu, Song Yub Shin, Jeong Kyu Bang
In this study, we report on the first chemical synthesis of ultra-short pyrazole-arginine based antimicrobial peptidomimetics derived from the newly synthesized N-alkyl/aryl pyrazole amino acids. Through the systematic tuning of hydrophobicity, charge, and peptide length, we identified the shortest peptide Py11 with the most potent antimicrobial activity. Py11 displayed greater antimicrobial activity against antibiotic-resistant bacteria, including MRSA, MDRPA, and VREF, which was approximately 2-4 times higher than that of melittin...
September 23, 2016: European Journal of Medicinal Chemistry
Tuanjie Wang, Jian Zhang, Aiju Xiao, Weiqing Liu, Yun Shang, Jindou An
Viral myocarditis (VMC) is characterized as an inflammatory process of the myocardium and can be fatal in infants and children. Melittin is a major polypeptide in honey bee venom that has been traditionally used against inflammation. However, its effect on VMC and the underlying molecular mechanism has not been reported. In this study, BALB/c mice were intraperitoneally injected with CVB3 to build a VMC model and treated with melittin. The results showed that melittin increased the mice's body weight and inhibited CVB3 replication...
September 28, 2016: Biochemical and Biophysical Research Communications
Cui-Cui Liu, Ding-Jun Hao, Qian Zhang, Jing An, Jing-Jing Zhao, Bo Chen, Ling-Ling Zhang, Hao Yang
Bee venom and its main constituent melittin (MEL) have been extensively studied in the treatment of tumors. However, the non-specific cytotoxicity and hemolytic activity have hampered the clinical application. Currently, a number of research groups have reported a series of optimization strategies, including gene therapy, recombinant immunotoxin incorporating MEL or MEL nanoparticles, targeting tumor cells to attenuate the cytotoxicity and improve its antitumor efficiency and therapeutic capabilities, which have shown very promising in overcoming some of these obstacles...
September 27, 2016: Cancer Chemotherapy and Pharmacology
Angela Ching Ling Teoh, Kyoung-Hwa Ryu, Eun Gyo Lee
The concern of the use of melittin in honey bee venom due to its adverse reaction caused by allergens such as phospholipase A2 (PLA₂) and hyaluronidase (HYA) has been an obstacle towards its usage. We developed a novel single-step method for melittin purification and the removal of PLA₂ and HYA. This study explores the influence of pH, buffer compositions, salt concentration and types of cation-exchange chromatography resins on the recovery of melittin and the removal of both HYA and PLA₂. Melittin can be readily purified with a strong cation-exchange resin at pH 6...
September 23, 2016: Journal of Microbiology and Biotechnology
Vladimir S Trubetskoy, Jacob B Griffin, Anthony L Nicholas, Eric M Nord, Zhao Xu, Ryan M Peterson, Christine I Wooddell, David B Rozema, Darren H Wakefield, David L Lewis, Steven B Kanner
The RNA interference (RNAi)-based therapeutic ARC-520 for chronic hepatitis B virus (HBV) infection consists of a melittin-derived peptide conjugated to N-acetylgalactosamine for hepatocyte targeting and endosomal escape, and cholesterol-conjugated RNAi triggers, which together result in HBV gene silencing. To characterize the kinetics of RNAi trigger delivery and 5'-phosphorylation of guide strands correlating with gene knockdown, we employed a peptide-nucleic acid (PNA) hybridization assay. A fluorescent sense strand PNA probe binding to RNAi duplex guide strands was coupled with anion exchange high performance liquid chromatography to quantitate guide strands and metabolites...
September 19, 2016: Nucleic Acids Research
Alina Theisen, Bin Yan, Jeffery M Brown, Michael Morris, Bruno Bellina, Perdita E Barran
We demonstrate the capabilities of a laser-coupled ion mobility mass spectrometer for analysis of peptide sequence and structure showing ultraviolet photodissociation (UVPD) spectra of mass and mobility selected ions. A Synapt G2-S mass spectrometer has been modified to allow photointeraction of ions post the mobility cell. For this work, we have employed a single wavelength laser, which irradiates at 266 nm. We present the unique capabilities of this instrument and demonstrate several key features. Irradiation of luteinizing hormone releasing hormone (LHRH), growth hormone releasing hexapeptide (GHRP-6), and TrpCage (sequence NLYIQWLKDGGPSSGRPPPS) yields extensive b- and y-type fragmentation as well as a- and c-type ions...
October 3, 2016: Analytical Chemistry
Hyun-Jin An, Jung-Yeon Kim, Woon-Hae Kim, Sang-Mi Han, Kwan-Kyu Park
Renal fibrosis is the principal pathological process underlying the progression of chronic kidney disease that leads to end-stage renal disease. Melittin is a major component of bee venom, and it has anti-bacterial, anti-viral, and anti-inflammatory properties in various cell types. Thus, this study examined the therapeutic effects of melittin on the progression of renal fibrosis using the unilateral ureteral obstruction (UUO) model. In addition, the effects of melittin on inflammation and fibrosis in renal fibroblast cells were explored using transforming growth factor-β1 (TGF-β1)...
2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Mi-Gyeong Kim, Yuna Shon, Jinyoung Kim, Yu-Kyoung Oh
BACKGROUND: The tumor microenvironment has recently emerged as a new target of anticancer chemotherapy. Selective activation of anticancer chemotherapy in the tumor microenvironment would further reduce the toxicity of anticancer drugs toward normal tissues. Fibroblast activation protein (FAP) is known to be selectively overexpressed on cancer-associated fibroblasts (CAFs) in the tumor microenvironment. Here, we designed an anticancer chemotherapeutic system based on promelittin, a peptide toxin that is selectively converted from an inactive form to the pore-forming melittin upon cleavage by FAP in the tumor microenvironment...
January 2017: Journal of the National Cancer Institute
Leonard T Nguyen, Hans J Vogel
Staphylokinase (Sak) is a plasminogen activator protein that is secreted by many Staphylococcus aureus strains. Sak also offers protection by binding and inhibiting specific antimicrobial peptides (AMPs). Here, we evaluate Sak as a more general interaction partner for AMPs. Studies with melittin, mCRAMP, tritrpticin and bovine lactoferricin indicate that the truncation of the first ten residues of Sak (SakΔN10), which occurs in vivo and uncovers important residues in a bulge region, improves its affinity for AMPs...
2016: Scientific Reports
Xuelei Lai, Montserrat Soler-Lopez, Harry J Wichers, Bauke W Dijkstra
Human tyrosinase (TYR) is a glycoprotein that initiates the first two reactions in the melanin biosynthesis pathway. Mutations in its encoding gene cause Oculocutaneous Albinism type I (OCA1), the most severe form of albinism, which is a group of autosomal recessive disorders characterized by reduced or absent production of melanin in skin, hair and eyes. Despite extensive structural and characterization studies of its homologues in lower eukaryotic organisms, the catalytic mechanism of human TYR and the molecular basis of OCA1 are largely unknown...
2016: PloS One
Durgesh K Rai, Shuo Qian, William T Heller
Membrane-active peptides (MAPs), which interact directly with the lipid bilayer of a cell and include toxins and host defense peptides, display lipid composition-dependent activity. Phosphatidylserine (PS) lipids are anionic lipids that are found throughout the cellular membranes of most eukaryotic organisms where they serve as both a functional component and as a precursor to phosphatidylethanolamine lipids. The inner leaflet of the plasma membrane contains more PS than the outer one, and the asymmetry is actively maintained...
August 13, 2016: Biochimica et Biophysica Acta
Xueting Li, Di Zhao, Xiaodi Shi, Gao Qiu, Xihua Lu
Monodisperse temperature/pH sensitive poly(N,N-diethylacrylamide/acrylic acid) (P(DEA/AAc)) nanogels with high contents of AAc up to 40 wt% have been prepared. In this study, it was unexpectedly found that the polydispersity of the nanogels with 40 wt% AAc strongly depended on the initiator concentration. Monodisperse P(DEA/AA) nanogels were synthesized only at a very low concentration of initiator. The phase transition behavior of the nanogels in water can be tuned by pH and temperature. Due to low polydispersity, the nanogels self-assembled into colloidal crystals at different temperatures below the volume phase transition temperature (VPTT)...
September 21, 2016: Soft Matter
Hiroaki Ishida, Leonard T Nguyen, Ramamourthy Gopal, Tomoyasu Aizawa, Hans J Vogel
In recent years, the increasing number of antibiotic-resistant bacteria has become a serious health concern. Antimicrobial peptides (AMPs) are an important component of the innate immune system of most organisms. A better understanding of their structures and mechanisms of action would lead to the design of more potent and safer AMPs as alternatives for current antibiotics. For detailed investigations, effective recombinant production which allows the facile modification of the amino acid sequence, the introduction of unnatural amino acids, and labeling with stable isotopes for nuclear magnetic resonance (NMR) studies is desired...
September 7, 2016: Journal of the American Chemical Society
André F Ferreira, Akhilesh Rai, Lino Ferreira, Pedro N Simões
The immobilization of gold nanoparticles (AuNPs) with antimicrobial peptides (AMPs) is a new and promising way to enhance both the activity and targeting capabilities of AMPs. However, a full understanding of the adsorption process underlying these materials is still lacking. Cecropin-melittin is a peptide with a broad antimicrobial activity while displaying low hemolytic properties, whose conjugation with AuNPs has not been studied before. In this context, we report the investigation of the adsorption process of the cecropin-melittin peptide, with (CM-SH) and without (CM) cysteine at its C-terminus, onto a gold surface based on all-atom MD simulations...
July 28, 2016: European Biophysics Journal: EBJ
Xiujuan Ye, Suzhen Guan, Jiwen Liu, Charlene C W Ng, Gabriel H H Chan, Stephen C W Sze, Kalin Y Zhang, Ryno Naude, Krzysztof Rolka, Jack Ho Wong, Tzi Bun Ng
The variety of proteins and peptides isolated from honey bee venom and wasp venom includes melittin, adiapin, apamine, bradykinin, cardiopep, mast cell degranulating peptide, mastoparan, phospholipase A2 and secapin. Some of the activities they demonstrate may find therapeutic applications.
2016: Protein and Peptide Letters
Benjamín Caruso, Ernesto E Ambroggio, Natalia Wilke, Gerardo Daniel Fidelio
We determined the rheological properties of β-amyloid Langmuir films at the air/water interface, a peptide whose interfacial structure is extended β-sheet, and compared them with those of films composed of Melittin (Mel), which adopts an α-helical conformation at neutral pH. To determine the dilatational and shear moduli we evaluated the response of pure peptide monolayers to an oscillatory anisotropic compressive work. Additionally, a micro-rheological characterization was performed by tracking the diffusion of micrometer sized latex beads onto the interface...
October 1, 2016: Colloids and Surfaces. B, Biointerfaces
Matthew G Burton, Qi M Huang, Mohammed A Hossain, John D Wade, Enzo A Palombo, Michelle L Gee, Andrew H A Clayton
Antimicrobial peptides are promising therapeutic alternatives to counter growing antimicrobial resistance. Their precise mechanism of action remains elusive, however, particularly with respect to live bacterial cells. We investigated the interaction of a fluorescent melittin analogue with single giant unilamellar vesicles, giant multilamellar vesicles, and bilamellar Gram-negative Escherichia coli (E. coli) bacteria. Time-lapse fluorescence lifetime imaging microscopy was employed to determine the population distribution of the fluorescent melittin analogue between pore state and membrane surface state, and simultaneously measure the leakage of entrapped fluorescent species from the vesicle (or bacterium) interior...
June 28, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
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