Gramicidin
(Synonyms: 短杆菌肽) 目录号 : GC32076A polypeptide antibiotic mixture
Cas No.:1405-97-6
Sample solution is provided at 25 µL, 10mM.
Quality Control & SDS
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- Purity: >98.00%
- COA (Certificate Of Analysis)
- SDS (Safety Data Sheet)
- Datasheet
Cell experiment: |
Microbes and dispersions are mixed and interacted for one hour before being diluted up to 20,000-fold for plating of 0.1 mL of each in triplicate and incubation (24 hours for 37°C) for CFU counting. Cell survival (%), taken as the mean±standard deviation, is plotted against DODAB and/or Gramicidin concentration. As a control for cell viability in the absence of DODAB or DODAB/Gramicidin dispersions, a standard bacterial suspension is added to 0.264 M D-glucose solution, diluted, and spreaded on the agar plate[1]. |
References: [1]. Ragioto DA, et al. Novel gramicidin formulations in cationic lipid as broad-spectrum microbicidal agents. Int J Nanomedicine. 2014 Jun 30;9:3183-92. |
Gramicidin is a polypeptide antibiotic mixture of gramicidin A , gramicidin B, and gramicidin C originally isolated from B. brevis.1 It is also a component of the antibiotic tyrothricin .2 Gramicidin is active against the Gram-positive bacterium S. aureus but not Gram-negative E. coli.3 It also protects mice from Pneumococcus infection in vivo when administered at a dose of 0.002 mg/animal. Gramicidin inhibits growth of bacteria by forming pores and channels in the cell wall, which increases its permeability to monovalent cations.1 Formulations containing gramicidin have been used as topical agents in the treatment of bacterial skin infections.
1.Wallace, B.A.Gramicidin channels and poresAnnu. Rev. Biophys. Biophys. Chem.19127-157(1990) 2.Brewer, G.A.GramicidinAnalytical profiles of drug substances8179-218(1979) 3.Dubos, R.J., and Hotchkiss, R.D.The production of bactericidal substances by aerobic sporulating bacilliJ. Exp. Med.73(5)629-640(1941)
Cas No. | 1405-97-6 | SDF | |
别名 | 短杆菌肽 | ||
Canonical SMILES | [Gramicidin] | ||
分子式 | C99H140N20O17 | 分子量 | 1882.3 |
溶解度 | DMSO : ≥ 100 mg/mL (53.13 mM);Water : < 0.1 mg/mL (insoluble) | 储存条件 | Store at -20°C |
General tips | 请根据产品在不同溶剂中的溶解度选择合适的溶剂配制储备液;一旦配成溶液,请分装保存,避免反复冻融造成的产品失效。 储备液的保存方式和期限:-80°C 储存时,请在 6 个月内使用,-20°C 储存时,请在 1 个月内使用。 为了提高溶解度,请将管子加热至37℃,然后在超声波浴中震荡一段时间。 |
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Shipping Condition | 评估样品解决方案:配备蓝冰进行发货。所有其他可用尺寸:配备RT,或根据请求配备蓝冰。 |
制备储备液 | |||
1 mg | 5 mg | 10 mg | |
1 mM | 0.5313 mL | 2.6563 mL | 5.3126 mL |
5 mM | 0.1063 mL | 0.5313 mL | 1.0625 mL |
10 mM | 0.0531 mL | 0.2656 mL | 0.5313 mL |
第一步:请输入基本实验信息(考虑到实验过程中的损耗,建议多配一只动物的药量) | ||||||||||
给药剂量 | mg/kg | 动物平均体重 | g | 每只动物给药体积 | ul | 动物数量 | 只 | |||
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% DMSO % % Tween 80 % saline | ||||||||||
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工作液浓度: mg/ml;
DMSO母液配制方法: mg 药物溶于 μL DMSO溶液(母液浓度 mg/mL,
体内配方配制方法:取 μL DMSO母液,加入 μL PEG300,混匀澄清后加入μL Tween 80,混匀澄清后加入 μL saline,混匀澄清。
1. 首先保证母液是澄清的;
2.
一定要按照顺序依次将溶剂加入,进行下一步操作之前必须保证上一步操作得到的是澄清的溶液,可采用涡旋、超声或水浴加热等物理方法助溶。
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Gramicidin channels
IEEE Trans Nanobioscience 2005 Mar;4(1):10-20.PMID:15816168DOI:10.1109/tnb.2004.842470.
Gramicidin channels are mini-proteins composed of two tryptophan-rich subunits. The conducting channels are formed by the transbilayer dimerization of nonconducting subunits, which are tied to the bilayer/solution interface through hydrogen bonds between the indole NH groups and the phospholipid backbone and water. The channel structure is known at atomic resolution and the channel's permeability characteristics are particularly well defined: Gramicidin channels are selective for monovalent cations, with no measurable permeability to anions or polyvalent cations; ions and water move through a pore whose wall is formed by the peptide backbone; and the single-channel conductance and cation selectivity vary when the amino acid sequence is varied, even though the permeating ions make no contact with the amino acid side chains. Given the amount of experimental information that is available--for both the wild-type channels and for channels formed by amino acid-substituted Gramicidin analogues--gramicidin channels provide important insights into the microphysics of ion permeation through bilayer-spanning channels. For the same reason, Gramicidin channels constitute the system of choice for evaluating computational strategies for obtaining mechanistic insights into ion permeation through the complex channels formed by integral membrane proteins.
Photoelectron Circular Dichroism of Electrosprayed Gramicidin Anions
J Phys Chem Lett 2022 Jul 7;13(26):6110-6116.PMID:35759344DOI:10.1021/acs.jpclett.2c01437.
Many sophisticated approaches for analyzing properties of chiral matter have been developed in recent years. But in general, the available chiroptical methods are limited to either solvated or small gaseous molecules. Studying the chirality of large biopolymers in the gas phase, including aspects of the secondary structure, becomes accessible by combining the electrospray ionization technique with chiroptical detection protocols. Here, laser-induced photodetachment from Gramicidin anions, a peptide consisting of 15 amino acids has been investigated. The angular distribution of photoelectrons is demonstrated to be sensitive to the substitution of protons by cesium ions, which is accompanied by a conformational change. The photoelectron circular dichroism (PECD) is -0.5% for bare Gramicidin, whereas Gramicidin with several Cs+ ions attached exhibits a PECD of +0.5%. The results are complemented and supported by ion mobility studies. The presented approach offers the prospect of studying chirality and the secondary structure of various biopolymers.
The Gramicidin ion channel: a model membrane protein
Biochim Biophys Acta 2007 Sep;1768(9):2011-25.PMID:17572379DOI:10.1016/j.bbamem.2007.05.011.
The linear peptide Gramicidin forms prototypical ion channels specific for monovalent cations and has been extensively used to study the organization, dynamics and function of membrane-spanning channels. In recent times, the availability of crystal structures of complex ion channels has challenged the role of Gramicidin as a model membrane protein and ion channel. This review focuses on the suitability of Gramicidin as a model membrane protein in general, and the information gained from Gramicidin to understand lipid-protein interactions in particular. Special emphasis is given to the role and orientation of tryptophan residues in channel structure and function and recent spectroscopic approaches that have highlighted the organization and dynamics of the channel in membrane and membrane-mimetic media.
Gramicidin A is hydrolyzed by a d-stereospecific peptidase produced by Bacillus anthracis
Environ Microbiol Rep 2022 Aug;14(4):570-576.PMID:35403341DOI:10.1111/1758-2229.13069.
Previously we described the discovery of a Bacillus spp. specific peptidase activity related to d-stereospecific peptidases (DSPs). The peptidase showed a strong preference for d-leucine and d-valine amino acids. These amino acids are present in the structure of the non-ribosomal peptide (NRP) antibiotics Gramicidin A, B and C and polymyxin E. To examine if the Bacillus spp. DSP-related peptidase can hydrolyze these NRPs, the effect of Gramicidin A and C and polymyxin E on peptidase activity in Bacillus anthracis culture supernatant was monitored. It was found that both gramicidins inhibited the DSP-related activity in a competitive manner. MALDI-TOF analysis revealed that upon incubation with B. anthracis culture supernatant Gramicidin A hydrolyzation products appeared. This study shows that the Bacillus spp. specific DSP-like peptidase was potentially produced by the bacteria to gain intrinsic resistance against NRP antibiotics. These results are of utmost importance in research towards antimicrobial resistance, whereas transfer of DSP-related activity to other clinically relevant pathogens can be a serious threat to human health.
Engineering the Gramicidin channel
Annu Rev Biophys Biomol Struct 1996;25:231-58.PMID:8800470DOI:10.1146/annurev.bb.25.060196.001311.
The chemical design or redesign of proteins with significant biological activity presents formidable challenges. Ion channels offer advantages for such design studies because one can examine the function of single molecular entities in real time. Gramicidin channels are attractive for study because of their known structure and exceptionally well-defined function. This article focuses on amino acid sequence changes that redesign the structure or function of Gramicidin channels. New, and functional, folded states have been achieved. In some cases, a single amino acid sequence can give rise to several (up to three) functional conformations. Single amino acid substitutions confer voltage-dependent channel gating. The findings provide insight into the folding of integral membrane proteins, the importance of tryptophan residues at the membrane/water interface, and the mechanism of channel gating.