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Journal articles on the topic 'Gramicidin'

Author: Grafiati

Published: 4 June 2021

Last updated: 25 April 2022

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1

Sugár, István, Alexander Bonanno, and Parkson Chong. "Gramicidin Lateral Distribution in Phospholipid Membranes: Fluorescence Phasor Plots and Statistical Mechanical Model." International Journal of Molecular Sciences 19, no. 11 (November 21, 2018): 3690. http://dx.doi.org/10.3390/ijms19113690.

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When using small mole fraction increments to study gramicidins in phospholipid membranes, we found that the phasor dots of intrinsic fluorescence of gramicidin D and gramicidin A in dimyristoyl-sn-glycero-3-phosphocholine (DMPC) unilamellar and multilamellar vesicles exhibit a biphasic change with peptide content at 0.143 gramicidin mole fraction. To understand this phenomenon, we developed a statistical mechanical model of gramicidin/DMPC mixtures. Our model assumes a sludge-like mixture of fluid phase and aggregates of rigid clusters. In the fluid phase, gramicidin monomers are randomly distributed. A rigid cluster is formed by a gramicidin dimer and DMPC molecules that are condensed to the dimer, following particular stoichiometries (critical gramicidin mole fractions, Xcr including 0.143). Rigid clusters form aggregates in which gramicidin dimers are regularly distributed, in some cases, even to superlattices. At Xcr, the size of cluster aggregates and regular distributions reach a local maximum. Before a similar model was developed for cholesterol/DMPC mixtures (Sugar and Chong (2012) J. Am. Chem. Soc. 134, 1164–1171) and here the similarities and differences are discussed between these two models.

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2

Olczak, A., M. L. Główka, M. Szczesio, J. Bojarska, Z. Wawrzak, and W. L. Duax. "The first crystal structure of a gramicidin complex with sodium: high-resolution study of a nonstoichiometric gramicidin D–NaI complex." Acta Crystallographica Section D Biological Crystallography 66, no. 8 (July 9, 2010): 874–80. http://dx.doi.org/10.1107/s0907444910019876.

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The crystal structure of the nonstoichiometric complex of gramicidin D with NaI has been studied using synchrotron radiation at 100 K. The limiting resolution was 1.25 Å and theRfactor was 16% for 19 883 observed reflections. The general architecture of the antiparallel two-stranded gramicidin dimers in the studied crystal was a right-handed antiparallel double-stranded form that closely resembles the structures of other right-handed species published to date. However, there were several surprising observations. In addition to the significantly different composition of linear gramicidins identified in the crystal structure, including the absence of the gramicidin C form, only two cationic sites were found in each of the two independent dimers (channels), which were partially occupied by sodium, compared with the seven sites found in the RbCl complex of gramicidin. The sum of the partial occupancies of Na+was only 1.26 per two dimers and was confirmed by the similar content of iodine ions (1.21 ions distributed over seven sites), which was easily visible from their anomalous signal. Another surprising observation was the significant asymmetry of the distributions and occupancies of cations in the gramicidin dimers, which was in contrast to those observed in the high-resolution structures of the complexes of heavier alkali metals with gramicidin D, especially that of rubidium.

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3

Antoinette Killian, J. "Gramicidin and gramicidin-lipid interactions." Biochimica et Biophysica Acta (BBA) - Reviews on Biomembranes 1113, no. 3-4 (December 1992): 391–425. http://dx.doi.org/10.1016/0304-4157(92)90008-x.

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4

Andersen, O. S., R. E. Koeppe, and B. Roux. "Gramicidin Channels." IEEE Transactions on Nanobioscience 4, no. 1 (March 2005): 10–20. http://dx.doi.org/10.1109/tnb.2004.842470.

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5

Bali, Doreen, Lionel King, and Sungho Kim. "Syntheses of New Gramicidin A Derivatives." Australian Journal of Chemistry 56, no. 4 (2003): 293. http://dx.doi.org/10.1071/ch02142.

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Gramicidin A was covalently coupled with theophylline, thyroxine, digoxigenin, and biotin. New compounds were synthesized when the four molecules were coupled to ethanolamine on the C-terminus of gramicidin. Peptidic linkers were inserted between gramicidin and the bio-molecules.

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6

MacLeod, R. J., F. Redican, P. Lembessis, J. R. Hamilton, and M. Field. "Sodium-bicarbonate cotransport in guinea pig ileal crypt cells." American Journal of Physiology-Cell Physiology 270, no. 3 (March 1, 1996): C786—C793. http://dx.doi.org/10.1152/ajpcell.1996.270.3.c786.

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Prior studies show that ileal HCO3- secretion is of crypt origin, possibly involving Na+-HCO3- cotransport. To test for the latter, we isolated crypt cells from guinea pig ileum and determined effects of medium HCO3-, Na+, K+, disulfonic stilbenes, and gramicidin on intracellular pH [pHi;2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein fluorescence], cell volume (electronic sizing), and Na+ efflux from 22Na+ -preloaded cells. Ileal crypt cells alkalinized when placed in sodium gluconate-HCO3- medium containing N-5-methyl-5-isobutyl amiloride (1 microM), bumetanide (10 microM) and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (250 microM which blocks Cl-/HCO3- exchange but not Na+ dependent HCO3- uptake). Depolarization with either gramicidin (50 microM) or 50 mM K+ caused a further 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS)-inhibitable increase in pHi. Gramicidin also caused SITS-inhibitable cell swelling. Both gramicidin effects were Na+ dependent: at 0 mM Na+, gramicidin acidified and did not alter cell volume; at 25 mM, gramicidin also acidified; at 90 and 140 mM, gramicidin alkalinized and induced cell swelling. HCO3- -dependent SITS-inhibitable Na+ efflux from 22Na+ -preloaded cells was also seen. We conclude that ileal crypt cells engage in electrogenic Na+ -HCO3- symport.

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7

Cox, J. A., M. Milos, and M. Comte. "High-affinity formation of a 2:1 complex between gramicidin S and calmodulin." Biochemical Journal 246, no. 2 (September 1, 1987): 495–502. http://dx.doi.org/10.1042/bj2460495.

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Two molecules of gramicidin S, a very rigid cyclic decapeptide rich in beta-sheet structure, can bind in a Ca2+-dependent way to a calmodulin molecule in the presence as well as in the absence of 4 M-urea. The flow-microcalorimetric titration of 25 microM-calmodulin with gramicidin S at 25 degrees C is endothermic for 21.3 kJ.mol-1; the enthalpy change is strictly linear up to a ratio of 2, indicating that the affinity constant for binding of the second gramicidin S is at least 10(7) M-1. In 4 M-urea the peptide quantitatively displaces seminalplasmin from calmodulin, as monitored by tryptophan fluorescence. An iterative data treatment of these competition experiments revealed strong positive co-operativity with K1 less than 5 × 10(5) M-1 and K1.K2 = 2.8 × 10(12) M-2. A competition assay with the use of immobilized melittin enabled us to monitor separately the binding of the second gramicidin S molecule: the K2 value is 1.9 × 10(7) M-1. By complementarity, the K1 value is 1.5 × 10(5) M-1. In the absence of urea the seminalplasmin displacement is incomplete: the data analysis shows optimal fitting with K1 less than 2 × 10(4) M-1 and K1.K2 = 3.2 × 10(11) M-2 and reveals that the mixed complex (calmodulin-seminalplasmin-gramicidin S) is quite stable and is even not fully displaced from calmodulin at high concentrations of gramicidin S. The activation of bovine brain phosphodiesterase by calmodulin is not impaired up to 0.2 microM-gramicidin S. According to our model the ternary complex enzyme-calmodulin-gramicidin is relatively important and displays the same activity as the binary complex enzyme-calmodulin. Gramicidin S also displaces melittin from calmodulin synergistically, as monitored by c.d. Our studies with gramicidin S reveal the importance of multipoint attachments in interactions involving calmodulin and confirm the heterotropic co-operativity in the binding of calmodulin antagonists first demonstrated by Johnson [(1983) Biochem. Biophys. Res. Commun. 112, 787-793].

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8

Drannikov, A. A., I. S. Vatlin, M. Е. Trusova, A. Di Martino, S. V. Krivoshchekov, А. M. Guriev, and M. V. Belousov. "Investigation of Colloidal Structure and Biopharmaceutical Properties of New Antibacterial Composition of Gramicidin S." Drug development & registration 10, no. 4 (November 25, 2021): 129–37. http://dx.doi.org/10.33380/2305-2066-2021-10-4-129-137.

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Introduction. Gramicidin S has been conventionally manufactured as buccal tablets. However, in the past decade, the interest in the development of spray formulations has been growing. Those formulations contain excipients that enhance the solubility of the antibiotic in water solutions. However, the real structure of gramicidin S containing sprays remains unrevealed.Aim. Investigation of colloidal structure and biopharmaceutical properties of new gramicidin S antibacterial composition.Materials and methods. The composition sample was obtained using gramicidin S dihydrochloride, propylene glycol, polysorbate-80, ethanol and purified water. Raman spectroscopy has been performed to determine the composition of the phases. Dynamic light scattering analysis was performed to characterize the composition particles. Release of gramicidin S was performed by dialysis method and the concentration was determined by HPLC. The antimicrobial properties were investigated in accordance with the requirements of the XIV edition of the Russian pharmacopoeia.Results and discussion. Dynamic light scattering analysis results show gramicidin S formulation particles having an average size in solution 5–50 nm and ζ-potential (–1.1: +7.9 mV). Based on the obtained data on the composition properties and formulation parameters it was classified as colloidal solution. The kinetic stability evaluation was performed. We compared the solubility in water and release parameters of the active pharmaceutical ingredient in the native state and in the micelles. The enhancement of the antimicrobial activity of the peptide in the colloidal solution was confirmed and ascribed to the synergic effect gramicidin S – surfactant.Conclusion. We reported the colloidal type of the composition, that aggregate gramicidin S at a concentration of 8 mg/mL. We found that gramicidin S inclusion into the colloidal solution led to significant efficiency increase, which reveals the potential to reduce the drug dose and side effects level.

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9

Carillo, Kathleen D., Chi-Jen Lo, Der-Lii M. Tzou, Yi-Hung Lin, Shang-Ting Fang, Shu-Hsiang Huang, and Yi-Cheng Chen. "The Effect of Calcium and Halide Ions on the Gramicidin A Molecular State and Antimicrobial Activity." International Journal of Molecular Sciences 21, no. 17 (August 27, 2020): 6177. http://dx.doi.org/10.3390/ijms21176177.

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Gramicidin A (gA) forms several convertible conformations in different environments. In this study, we investigated the effect of calcium halides on the molecular state and antimicrobial activity of gramicidin A. The molecular state of gramicidin A is highly affected by the concentration of calcium salt and the type of halide anion. Gramicidin A can exist in two states that can be characterized by circular dichroism (CD), mass, nuclear magnetic resonance (NMR) and fluorescence spectroscopy. In State 1, the main molecular state of gramicidin A is as a dimer, and the addition of calcium salt can convert a mixture of four species into a single species, which is possibly a left-handed parallel double helix. In State 2, the addition of calcium halides drives gramicidin A dissociation and denaturation from a structured dimer into a rapid equilibrium of structured/unstructured monomer. We found that the abilities of dissociation and denaturation were highly dependent on the type of halide anion. The dissociation ability of calcium halides may play a vital role in the antimicrobial activity, as the structured monomeric form had the highest antimicrobial activity. Herein, our study demonstrated that the molecular state was correlated with the antimicrobial activity.

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10

Poxleitner, M., J. Seitz-Beywl, and K. Heinzinger. "Ion Transport through Gramicidin A. Water Structure and Functionality." Zeitschrift für Naturforschung C 48, no. 7-8 (August 1, 1993): 654–65. http://dx.doi.org/10.1515/znc-1993-7-820.

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Dynamics (MD) simulations were performed on a gramicidin A dimer model representing a transmembrane channel. Different from previous simulations the peptide was in contact with bulk water at both ends of the dimer to guarantee a realistic description of the hydration of the biomolecule. The flexible BJH model for water was employed in the simulations and the gramicidin-water, gramicidin-ion and ion-water potentials used are based on molecular orbital calculations. The water structure near the gramicidin was investigated first by a simulation without ions, while for the energy profiles of the ion transport through the channel a potassium or a sodium ion was added. These investigations provide a detailed and conclusive picture on a molecular level of the role of water in the ion transport through a gramicidin A channel and can explain the experimental results on the selectivity between alkali ions, their double or even triple occupancy, the exclusion or permeability of anions depending upon cation concentration and the consequences of differences in the ionic charge. The investigation demonstrate that the water molecules around the gramicidin behave as an integral part of the peptide and the functionality is the result of the whole complex biomolecule-water.

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11

LELIEVRE, D., Y. TRUDELLE, F. HEITZ, and G. SPACH. "Synthesis and characterization of retro gramicidin A-dAla-gramicidin A, a 31-residue-long gramicidin analogue." International Journal of Peptide and Protein Research 33, no. 5 (January 12, 2009): 379–85. http://dx.doi.org/10.1111/j.1399-3011.1989.tb00698.x.

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12

Goforth, Robyn L., Aung K. Chi, Denise V. Greathouse, Lyndon L. Providence, Roger E. Koeppe, and Olaf S. Andersen. "Hydrophobic Coupling of Lipid Bilayer Energetics to Channel Function." Journal of General Physiology 121, no. 5 (April 28, 2003): 477–93. http://dx.doi.org/10.1085/jgp.200308797.

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The hydrophobic coupling between membrane-spanning proteins and the lipid bilayer core causes the bilayer thickness to vary locally as proteins and other “defects” are embedded in the bilayer. These bilayer deformations incur an energetic cost that, in principle, could couple membrane proteins to each other, causing them to associate in the plane of the membrane and thereby coupling them functionally. We demonstrate the existence of such bilayer-mediated coupling at the single-molecule level using single-barreled as well as double-barreled gramicidin channels in which two gramicidin subunits are covalently linked by a water-soluble, flexible linker. When a covalently attached pair of gramicidin subunits associates with a second attached pair to form a double-barreled channel, the lifetime of both channels in the assembly increases from hundreds of milliseconds to a hundred seconds—and the conductance of each channel in the side-by-side pair is almost 10% higher than the conductance of the corresponding single-barreled channels. The double-barreled channels are stabilized some 100,000-fold relative to their single-barreled counterparts. This stabilization arises from: first, the local increase in monomer concentration around a single-barreled channel formed by two covalently linked gramicidins, which increases the rate of double-barreled channel formation; and second, from the increased lifetime of the double-barreled channels. The latter result suggests that the two barrels of the construct associate laterally. The underlying cause for this lateral association most likely is the bilayer deformation energy associated with channel formation. More generally, the results suggest that the mechanical properties of the host bilayer may cause the kinetics of membrane protein conformational transitions to depend on the conformational states of the neighboring proteins.

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13

Markham, Jeffrey C., Joseph A. Gowen, Timothy A. Cross, and David D. Busath. "Comparison of gramicidin A and gramicidin M channel conductance dispersities." Biochimica et Biophysica Acta (BBA) - Biomembranes 1513, no. 2 (August 2001): 185–92. http://dx.doi.org/10.1016/s0005-2736(01)00353-4.

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14

Hori, K., and T. Kurotsu. "Characterization of Gramicidin S Synthetase Aggregation Substance: Control of Gramicidin S Synthesis by Its Product, Gramicidin S." Journal of Biochemistry 122, no. 3 (September 1, 1997): 606–15. http://dx.doi.org/10.1093/oxfordjournals.jbchem.a021796.

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15

Kleinkauf, H., and H. Von Döhren. "Applications of peptide synthetases in the synthesis of peptide analogues." Acta Biochimica Polonica 44, no. 4 (December 31, 1997): 839–47. http://dx.doi.org/10.18388/abp.1997_4389.

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Enzymatically formed peptides show positional variations as well as highly conserved amino acids. In the cases of gramicidin S, tyrocidine, linear gramicidins, enniatins, echinocandins and viridogrisein in vivo and in vitro studies indicate substrate selection at the level of amino acid activation as a major control step. Evidence for proof-reading steps beyond activation has been obtained in penicillin and cyclosporin biosynthesis. Activated substrate analogues may promote the formation of side products such as dipeptides and cyclodipeptides. Modifications of intermediates, such as N-methylation, influence the rates of peptide synthesis. These control steps pose limitations for the application of such enzyme systems in the production of peptide libraries. They may originate from a target oriented evolution of these synthetases.

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16

Abe, Y., K. Furukawa, Y. Itoyama, and N. Akaike. "Glycine response in acutely dissociated ventromedial hypothalamic neuron of the rat: new approach with gramicidin perforated patch-clamp technique." Journal of Neurophysiology 72, no. 4 (October 1, 1994): 1530–37. http://dx.doi.org/10.1152/jn.1994.72.4.1530.

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1. We investigated the glycine-induced response in ventromedial hypothalamic (VMH) neurons freshly dissociated from 8- to 12-day-old rats using the nystatin and gramicidin perforated patch recording modes. The nystatin-formed pores in the plasma membrane are permeable for both monovalent cations and anions, whereas those formed by gramicidin are permeable only to monovalent cations. Therefore, when the patch-pipette contains 150 mM Cl- and gramicidin, the physiological intracellular Cl- concentration ([Cl-]i) is undisturbed in the cell-attached condition of the pipette. 2. At holding potentials of -40 to -60 mV, glycine induced inward currents and outward currents in the nystatin and gramicidin perforated patch recording modes, respectively. The values of the half-maximum effective concentration (EC50) and the Hill coefficient in the concentration-response relationships of the glycine responses were 2.9 x 10(-5) M, 1.1, and 4.2 x 10(-5) M, 1.4, respectively. These values were quite similar in both recording modes. 3. The reversal potentials of the glycine responses (EGly) were -1.5 mV in the nystatin perforated patch recording and -75.0 to -24.8 mV in the gramicidin perforated patch recording. 4. Strychnine (3 x 10(-8) M) inhibited the glycine-induced outward currents in a competitive manner and the half-inhibition concentration (IC50) of strychnine on the 10(-4) M glycine-induced response was 1.9 x 10(-8) M. 5. The physiological [Cl-]i in the VMH neurons calculated from the EGly obtained by the gramicidin perforated patch mode ranged from 6.0 to 43.8 mM (n = 28).

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17

Koeppe, Roger E., Jean A. Paczkowski, and William L. Whaley. "Gramicidin K, a new linear channel-forming gramicidin from Bacillus brevis." Biochemistry 24, no. 12 (June 4, 1985): 2822–26. http://dx.doi.org/10.1021/bi00333a002.

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18

Wallace, B. A. "Structure of gramicidin A." Biophysical Journal 49, no. 1 (January 1986): 295–306. http://dx.doi.org/10.1016/s0006-3495(86)83642-6.

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19

Koeppe, R. E., M. J. Taylor, and O. S. Andersen. "Models for gramicidin channels." Biophysical Journal 61, no. 3 (March 1992): 831. http://dx.doi.org/10.1016/s0006-3495(92)81889-1.

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20

Wallace, B. A. "Gramicidin Channels and Pores." Annual Review of Biophysics and Biophysical Chemistry 19, no. 1 (June 1990): 127–57. http://dx.doi.org/10.1146/annurev.bb.19.060190.001015.

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21

Koeppe, R. E., and O. S. Anderson. "Engineering the Gramicidin Channel." Annual Review of Biophysics and Biomolecular Structure 25, no. 1 (June 1996): 231–58. http://dx.doi.org/10.1146/annurev.bb.25.060196.001311.

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22

Wallace, B. A. "Crystals of gramicidin A." Acta Crystallographica Section A Foundations of Crystallography 43, a1 (August 12, 1987): C39. http://dx.doi.org/10.1107/s0108767387084423.

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23

Stankovic, Charles J., Jose M. Delfino, and Stuart L. Schreiber. "Purification of gramicidin A." Analytical Biochemistry 184, no. 1 (January 1990): 100–103. http://dx.doi.org/10.1016/0003-2697(90)90019-6.

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24

Etchebest, Catherine, and Alberte Pullman. "The gramicidin A channel." FEBS Letters 204, no. 2 (August 18, 1986): 261–65. http://dx.doi.org/10.1016/0014-5793(86)80824-9.

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25

Orwa, J. A., C. Govaerts, E. Roets, A. Van Schepdael, and J. Hoogmartens. "Liquid chromatography of gramicidin." Chromatographia 53, no. 1-2 (January 2001): 17–21. http://dx.doi.org/10.1007/bf02492421.

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26

Naveen V M K and Veeraswami B. "Highly accurate and New approach for quantiϐication of Gramicidin in medication by RP-HPLC." International Journal of Research in Pharmaceutical Sciences 11, SPL4 (December 21, 2020): 3053–58. http://dx.doi.org/10.26452/ijrps.v11ispl4.4605.

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A significant Reverse Phase-High performance Liquid Chromatography technique was developed for a more accurate, unique and quick economical method was developed for the analysis of Gramicidin in medication dosage forms. The separation of this drug Gramicidin was done by using the X-Bridge phenyl column as a stationary phase, and a mixture of acetonitrile + buffer in 50:50 v/v ratio was used as a movable phase. The buffer used in this method was Octane sulphonic acid of pH-2.5 adjusted with OPA. The maximum absorbance of eluents was observed at 235 nm. A specific flow rate (1 ml/minute) was maintained throughout the runtime of 8 min. The selected drug is eluted at 2.49 minutes. The selected drug obeys Beer Lambert's law in the concentration range of 0.5-7.5 µg/ml of Gramicidin. The percentage of recovery was found to be within the acceptable limit. The selected approach was corroborated with ICH standard ground rules, and the results of parameters like method precision, accuracy, ruggedness, robustness, and degradation studies were found to be within the allowable limit. Thus, the present method was successfully applied for the simultaneous analysis of Gramicidin in routine industrial work.

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Brasseru, R., J. A. Killian, B. De Kruijff, and J. M. Ruysschaert. "Conformational analysis of gramicidin-gramicidin interactions at the air/water interface suggests that gramicidin aggregates into tube-like structures similar as found in the gramicidin-induced hexagonal HII phase." Biochimica et Biophysica Acta (BBA) - Biomembranes 903, no. 1 (September 1987): 11–17. http://dx.doi.org/10.1016/0005-2736(87)90150-7.

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Zhang, Lijuan, Pawandeep Dhillon, Hong Yan, Susan Farmer, and Robert E. W. Hancock. "Interactions of Bacterial Cationic Peptide Antibiotics with Outer and Cytoplasmic Membranes ofPseudomonas aeruginosa." Antimicrobial Agents and Chemotherapy 44, no. 12 (December 1, 2000): 3317–21. http://dx.doi.org/10.1128/aac.44.12.3317-3321.2000.

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ABSTRACT Polymyxins B and E1 and gramicidin S are bacterium-derived cationic antimicrobial peptides. The polymyxins were more potent than gramicidin S against Pseudomonas aeruginosa, with MICs of 0.125 to 0.25 and 8 μg/ml, respectively. These peptides differed in their affinities for binding to lipopolysaccharide, but all were able to permeabilize the outer membrane of wild-type P. aeruginosaPAO1 strain H103, suggesting differences in their mechanisms of self-promoted uptake. Gramicidin S caused rapid depolarization of the bacterial cytoplasmic membrane at concentrations at which no killing was observed within 30 min, whereas, conversely, the concentrations of the polymyxins that resulted in rapid killing resulted in minimal depolarization. These data indicate that the depolarization of the cytoplasmic membrane by these peptides did not correlate with bacterial cell lethality.

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Durkin, J. T., L. L. Providence, R. E. Koeppe, and O. S. Andersen. "Formation of non-beta 6.3-helical gramicidin channels between sequence-substituted gramicidin analogues." Biophysical Journal 62, no. 1 (April 1992): 145–59. http://dx.doi.org/10.1016/s0006-3495(92)81801-5.

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Carnini, Anna, Trinh T. Nguyen, and David T. Cramb. "Fluorescence quenching of gramicidin D in model membranes by halothane." Canadian Journal of Chemistry 85, no. 7-8 (July 1, 2007): 513–19. http://dx.doi.org/10.1139/v07-064.

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Inhaled anesthetics were introduced in surgery over a century ago. To this day, the molecular mechanism of anesthetic action remains largely unknown. However, ion-channels of neuronal membranes are believed to be the most- likely molecular targets of inhaled anesthetics. In the study presented here, we investigated the interaction of a simplified ion-channel system, gramicidin, with halothane, a small haloalkane inhaled anesthetic in various environments. Fluorescence-quenching experiments of gramicidin D in dioleoylphosphatidylcholine (DOPC) large unilamellar vesicles (LUVS) have shown that halothane can directly interact with the ion channel (KSV = 66 M–1). Halothane quenched the fluorescence from tryptophan residues located at the lipid bilayer – aqueous interfaces as well as those tryptophans located deeper in the bilayer. Quenching data from gramicidin D in sodium dodecyl sulfide (SDS) micelles revealed that the tryptophan residues located at the micelle–solvent interface were preferentially quenched by halothane (KSV = 22 M–1). In 1-octanol, fluorescence quenching was observed, but with a lower KSV value (KSV = 6 M–1) than in DOPC LUVS and SDS micelles. Taken together, these results indicate that halothane interactions with gramicidin, mediated by a lipid bilayer, are the strongest, and that the mechanism of anesthetic action may also be lipid-mediated.

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Fyles, Thomas M., Tony D. James, and Katharine C. Kaye. "Biomimetic ion transport: on the mechanism of ion transport by an artificial ion channel mimic." Canadian Journal of Chemistry 68, no. 6 (June 1, 1990): 976–78. http://dx.doi.org/10.1139/v90-153.

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The influx of cations into vesicles mediated by a synthetic transporter is coupled to proton efflux and may be quantified by a pH-stat technique. The dependence of the transport upon cation type and concentration, upon transporter concentration, and upon temperature has been examined. The synthetic transporter is closely similar to the natural channel forming compound gramicidin, and significantly different from the carrier valinomycin, with respect to the variables examined. Keywords: ion transport, vesicle membrane, channel, gramicidin, transport mechanism.

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32

Shireen, Tahsina, Madhuri Singh, Tiyasa Das, and Kasturi Mukhopadhyay. "Differential Adaptive Responses of Staphylococcus aureus toIn VitroSelection with Different Antimicrobial Peptides." Antimicrobial Agents and Chemotherapy 57, no. 10 (July 15, 2013): 5134–37. http://dx.doi.org/10.1128/aac.00780-13.

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ABSTRACTWe subjectedStaphylococcus aureusATCC 29213 to serial passage in the presence of subinhibitory concentrations of magainin 2 and gramicidin D for several hundred generations. We obtainedS. aureusstrains with induced resistance to magainin 2 (strain 55MG) and gramicidin D (strain 55GR) that showed different phenotypic changes in membrane properties. Both exhibited a change in membrane phospholipid content and an increase in membrane rigidity, while an alteration in net charge compared to that of the control occurred only in the case of 55MG.

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33

Goulian, M., O. N. Mesquita, D. K. Fygenson, C. Nielsen, O. S. Andersen, and A. Libchaber. "Gramicidin Channel Kinetics under Tension." Biophysical Journal 74, no. 1 (January 1998): 328–37. http://dx.doi.org/10.1016/s0006-3495(98)77790-2.

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34

Busath, D., and G. Szabo. "Permeation characteristics of gramicidin conformers." Biophysical Journal 53, no. 5 (May 1988): 697–707. http://dx.doi.org/10.1016/s0006-3495(88)83151-5.

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35

Malik, Abaid, Rosi Bissinger, Guoxing Liu, Guilai Liu, and Florian Lang. "Enhanced Eryptosis Following Gramicidin Exposure." Toxins 7, no. 5 (April 23, 2015): 1396–410. http://dx.doi.org/10.3390/toxins7051396.

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36

AKAIKE, Norio. "Gramicidin perforated patch recording technique." Folia Pharmacologica Japonica 113, no. 6 (1999): 339–47. http://dx.doi.org/10.1254/fpj.113.339.

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37

Arai, Toru, Takashi Imachi, Tamaki Kato, H. Iyehara Ogawa, Tsutomu Fujimoto, and Norikazu Nishino. "Synthesis of [Hexafluorovalyl1,1′]gramicidin S." Bulletin of the Chemical Society of Japan 69, no. 5 (May 1996): 1383–89. http://dx.doi.org/10.1246/bcsj.69.1383.

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38

Abo-Riziq, Ali, Bridgit O. Crews, Michael P. Callahan, Louis Grace, and Mattanjah S. de Vries. "Spectroscopy of Isolated Gramicidin Peptides." Angewandte Chemie International Edition 45, no. 31 (August 4, 2006): 5166–69. http://dx.doi.org/10.1002/anie.200601516.

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39

Abo-Riziq, Ali, Bridgit O. Crews, Michael P. Callahan, Louis Grace, and Mattanjah S. de Vries. "Spectroscopy of Isolated Gramicidin Peptides." Angewandte Chemie 118, no. 31 (August 4, 2006): 5290–93. http://dx.doi.org/10.1002/ange.200601516.

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40

Cornell, Bruce. "Gramicidin A-phospholipid model systems." Journal of Bioenergetics and Biomembranes 19, no. 6 (December 1987): 655–76. http://dx.doi.org/10.1007/bf00762301.

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41

Jones, Tyson L., Riqiang Fu, Frederick Nielson, Timothy A. Cross, and David D. Busath. "Gramicidin Channels Are Internally Gated." Biophysical Journal 98, no. 8 (April 2010): 1486–93. http://dx.doi.org/10.1016/j.bpj.2009.11.055.

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42

Nagamurthi, G., and S. Rambhav. "Gramicidin-S: Structure-activity relationship." Journal of Biosciences 7, no. 3-4 (June 1985): 323–29. http://dx.doi.org/10.1007/bf02716794.

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43

Evans, Frances, Julio A. Hernández, Federico Cabo, and Silvia Chifflet. "A Note of Caution: Gramicidin Affects Signaling Pathways Independently of Its Effects on Plasma Membrane Conductance." BioMed Research International 2021 (October 21, 2021): 1–12. http://dx.doi.org/10.1155/2021/2641068.

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Abstract:

Gramicidin is a thoroughly studied cation ionophore widely used to experimentally manipulate the plasma membrane potential (PMP). In addition, it has been established that the drug, due to its hydrophobic nature, is capable of affecting the organization of membrane lipids. We have previously shown that modifications in the plasma membrane potential of epithelial cells in culture determine reorganizations of the cytoskeleton. To elucidate the molecular mechanisms involved, we explored the effects of PMP depolarization on some putative signaling intermediates. In the course of these studies, we came across some results that could not be interpreted in terms of the properties of gramicidin as an ionic channel. The purpose of the present work is to communicate these results and, in general, to draw attention to the fact that gramicidin effects can be misleadingly attributed to its ionic or electrical properties. In addition, this work also contributes with some novel findings of the modifications provoked on the signaling intermediates by PMP depolarization and hyperpolarization.

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44

Nozaki, Sukekatsu, and Ichiro Muramatsu. "Natural Homologs of Gramicidin S. II. Synthesis of Gramicidin S-2 and S-3." Bulletin of the Chemical Society of Japan 58, no. 1 (January 1985): 331–35. http://dx.doi.org/10.1246/bcsj.58.331.

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45

Williams, Linda P., Elizabeth J. Narcessian, Olaf S. Andersen, George Waller, M. Jeffrey Taylor, John P. Lazenby, James F. Hinton, and Roger E. Koeppe. "Molecular and channel-forming characteristics of gramicidin K's: a family of naturally occurring acylated gramicidins." Biochemistry 31, no. 32 (August 1992): 7311–19. http://dx.doi.org/10.1021/bi00147a015.

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46

Camaleńo-Delgado, Jose-Miguel, Xiao Kang Zhao, and Janos H. Fendler. "Intrinsic gramicidin fluorescence lifetimes in bilayer lipid membranes and in vesicles." Canadian Journal of Chemistry 68, no. 6 (June 1, 1990): 888–96. http://dx.doi.org/10.1139/v90-140.

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Intrinsic Gramicidin A′ tryptophan steady-state fluorescence anisotropies and fluorescence lifetimes have been determined in bilayer lipid membranes (BLMs) prepared from glyceryl monooleate (GMO). In GMO BLMs, fluorescence anisotropy, the r value, was found to be 0.05 ± 0.02. Decays of Gramicidin A′ fluorescence intensities were fitted to the sum of three exponentials (τ1, τ2, and τ3) and appropriate pre-exponentials (A1, A2, and A3). These values allowed for the assessment of average fluorescence lifetimes, [Formula: see text]. These values related to those determined in vesicles prepared from dipalmitoylphosphatidylcholine (DPPC), dioleoylphosphatidylcholine (DOPC), distearoylphosphatidylcholine (DSPC), and diphytanoylphosphatidylcholine (DPhPC). In BLMs, [Formula: see text], 3.6 ns, and 2.3 ns were determined for vertically, horizontally, and unpolarized average fluorescence lifetimes, respectively. Increasing the applied potential across the BLM from 0 to 80 mV increased [Formula: see text] from 2.2 ns to 4.9 ns and τ1 from 0.43 ± 0.05 to 0.73 ± 0.06 ns, as well as the contributions and lifetimes of the longer lived fluorescence (A2 and A3, τ2 and τ3). The emission maximum of Gramicidin A′ (334 nm in DPPC) and the absence of quenching by iodide ions indicated complete incorporation of the polypeptide into vesicles. The r values were of the order of 0.10 in vesicles prepared from DPPC and DSPC, both in the absence and in the presence of added 1.2 × 10−4 M CsCl. In vesicles prepared from DOPC and DPhPC, r values increased to 0.13 and 0.14 in water and to 0.15 and 0.20 in 1.2 × 10−4 M CsCl, respectively. At 25.0 °C, the temperature of the measurements, DPPC and DSPC are in their "solid" states, but DOPC and DPhPC are in their "liquid" states, [Formula: see text] values for Gramicidin A′ in vesicles prepared from DPPC, DOPC, and DSPC were all in the 3.0 ± 0.3 ns range. In DPhPC vesicles, [Formula: see text] was determined. Time-dependent anisotropics became observable in DOPC and DPhPC vesicles, particularly in the presence of 1.2 × 10−4 M CsCl. Keywords: gramicidin, fluorescence lifetimes, vesicles, bilayer lipid membranes, time-dependent anisotropics.

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47

Tajima, Y., K. Ono, and N. Akaike. "Perforated patch-clamp recording in cardiac myocytes using cation-selective ionophore gramicidin." American Journal of Physiology-Cell Physiology 271, no. 2 (August 1, 1996): C524—C532. http://dx.doi.org/10.1152/ajpcell.1996.271.2.c524.

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Whole cell currents were recorded in single myocytes dissociated from guinea pig ventricles by the patch-clamp technique. The addition of 0.1 mg/ml gramicidin D, a cation-selective ionophore, into the pipette solution induced a gradual spontaneous perforation of the patch membrane under a conventional cell-attached configuration. The access resistance, measured at approximately 12 min after formation of a gigaohm seal, was 9.2 +/- 1.5 M omega (n = 12). The perforated patch membrane exhibited ionic selectivity for various monovalent cations, with a relative order of Cs+ (1.11) > K+ (1.0) > Na+ (0.65) >> tris(hydroxymethyl)aminomethane+ (approximately 0) but was not permeable for Cl-. Under the gramicidin-perforated patch recording configuration, the cells showed the typical electrophysiological properties for ventricular cells reported previously. The intracellular Cl- concentration, estimated from the reversal potential of the catecholamine-induced Cl- current, was 36.3 +/- 2.9 mM (n = 17). We thus conclude that the gramicidin-perforated patch recording mode provides a useful tool for recording the ionic currents while maintaining the intracellular Cl- concentration.

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48

Patrick, John W., Breanna Zerfas, Jianmin Gao, and David H. Russell. "Rapid capillary mixing experiments for the analysis of hydrophobic membrane complexes directly from aqueous lipid bilayer solutions." Analyst 142, no. 2 (2017): 310–15. http://dx.doi.org/10.1039/c6an02290a.

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Diamanti, Eleftheria, Eduart Gutiérrez-Pineda, Nikolaos Politakos, Patrizia Andreozzi, María José Rodriguez-Presa, Wolfgang Knoll, Omar Azzaroni, Claudio A. Gervasi, and Sergio E. Moya. "Gramicidin ion channels in a lipid bilayer supported on polyelectrolyte multilayer films: an electrochemical impedance study." Soft Matter 13, no. 47 (2017): 8922–29. http://dx.doi.org/10.1039/c7sm01539a.

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50

Tournois, H., P. Gieles, R. Demel, J. de Gier, and B. de Kruijff. "Interfacial properties of gramicidin and gramicidin-lipid mixtures measured with static and dynamic monolayer techniques." Biophysical Journal 55, no. 3 (March 1989): 557–69. http://dx.doi.org/10.1016/s0006-3495(89)82849-8.

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