1405-97-6 Usage
Description
Gramicidin is a polypeptide antibiotic mixture, primarily composed of gramicidin A, B, and C, originally isolated from Bacillus brevis. It is a component of the antibiotic tyrothricin and is known for its activity against Gram-positive bacteria, such as Staphylococcus aureus, while being less effective against Gram-negative bacteria like E. coli. Gramicidin functions by forming pores and channels in bacterial cell walls, increasing their permeability to monovalent cations and ultimately leading to bacterial cell death.
Uses
Used in Medicine (Antibacterial):
Gramicidin is used as a topical antimicrobial agent, particularly effective against Gram-positive bacteria. It is commonly used in the treatment of bacterial skin infections due to its ability to inhibit bacterial growth by forming channels in the cell membrane, causing ion leakage.
Used in Research:
Gramicidin serves as an essential bioprobe for understanding the nature of cell membranes. Its ionophore properties, which allow it to form channels in bacterial cell membranes, make it a valuable tool in studying membrane permeability and ion transport.
Used in Combination with Other Antibiotics:
Gramicidin is available in various topical preparations containing other antibiotics, such as bacitracin and neomycin. These combinations enhance the overall effectiveness of the treatment against a broader range of bacterial infections.
Used in Branded Products:
Gramicidin is marketed under the brand name Gramoderm (Schering) and is used in pharmaceutical formulations for its antimicrobial properties.
Chemical Properties:
Gramicidin is characterized by its white, crystalline platelet appearance. It is soluble in lower alcohols, acetic acid, and pyridine, moderately soluble in dry acetone and dioxane, and almost insoluble in water, ether, and hydrocarbons. It has the ability to depress surface tension and form a fairly stable colloidal emulsion in distilled water.
Antimicrobial activity
Gramicidin is highly active against many Gram-positive bacteria.
Neisseria spp. are relatively resistant. Gram-negative bacilli including
Pseudomonas aeruginosa are susceptible although conflicting data exist
about the degree of susceptibility. Gramicidin has a bactericidal activity against Mycoplasma
spp. and several pathogenic fungi, including Candida albicans.
Interestingly, it also appears to have antiviral activity against HIV
and herpes simplex viruses (HSV-1, HSV-2).
Pharmaceutical Applications
Gramicidin as used in topical formulations is a mixture of
several closely related compounds, of which about 80% is in
the form of gramicidin A. It is part of the tyrothricin complex
originally isolated from B. brevis.
It is active against most species of Gram-positive bacteria,
including mycobacteria. Gram-negative bacilli are completely
insensitive.
It is highly toxic to erythrocytes, liver and kidney, and is
used only in topical formulations, usually as one of several
components.
Biochem/physiol Actions
Linear polypeptide antibiotic mixture of gramicidin A, B, C, and D. Gramicidin A acts as neutral carrier and helps in the establishment of ion flux across the lipid bilayer.
Mechanism of action
The mechanisms of gramicidin’s bactericidal activity have not been
fully elucidated. Gramicidin is known to alter the function of the
bacterial cytoplasmic membrane by forming channels that destroy the
ion gradient and make it permeable for inorganic cations . It may also be a potent and
specific inhibitor of the transcription reaction and inhibit the binding
of DNA-dependent RNA polymerase (transcriptase) to DNA .
Gramicidin appears to have antiviral activity against HIV, HSV-1,
and HSV-2 viruses and is also used as a
contraceptive due to its spermostatic properties.
Clinical Use
The use of gramicidin is restricted to topical applications on wounds or
as ear and eye drops. Currently, much research is being invested to
generate less toxic analogs that still exhibit the same wide range of
bactericidal activity. To date, no new gramicidin-like polypeptides are
available for clinical use.
Gramicidin is used in some countries as a topical contraceptive,
because it has spermostatic activity.
Check Digit Verification of cas no
The CAS Registry Mumber 1405-97-6 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 1,4,0 and 5 respectively; the second part has 2 digits, 9 and 7 respectively.
Calculate Digit Verification of CAS Registry Number 1405-97:
(6*1)+(5*4)+(4*0)+(3*5)+(2*9)+(1*7)=66
66 % 10 = 6
So 1405-97-6 is a valid CAS Registry Number.
InChI:InChI=1/C60H92N12O10/c1-35(2)31-43-53(75)67-45(33-39-19-11-9-12-20-39)59(81)71-29-17-25-47(71)55(77)70-50(38(7)8)58(80)64-42(24-16-28-62)52(74)66-44(32-36(3)4)54(76)68-46(34-40-21-13-10-14-22-40)60(82)72-30-18-26-48(72)56(78)69-49(37(5)6)57(79)63-41(23-15-27-61)51(73)65-43/h9-14,19-22,35-38,41-50H,15-18,23-34,61-62H2,1-8H3,(H,63,79)(H,64,80)(H,65,73)(H,66,74)(H,67,75)(H,68,76)(H,69,78)(H,70,77)
1405-97-6Relevant articles and documents
Polar groups in membrane channels: Consequences of replacing alanines with serines in membrane-spanning gramicidin channels
Daily, Anna E.,Kim, Jung H.,Greathouse, Denise V.,Andersen, Olaf S.,Koeppe, Roger E.
, p. 6856 - 6865 (2010)
To explore the consequences of burying polar, hydrogen-bonding hydroxyl groups within the hydrocarbon core of lipid bilayer membranes, we examined the structural and functional effects of alanine-to-serine substitutions in bilayer-spanning gramicidin channels. A native Ala was replaced by Ser at position 3 or 5 in the gramicidin A (gA) sequence: formyl-VG2A 3LA5VVVWLWLWLW-ethanolamide (d-residues underlined). In the head-to-head dimers that form the conducting, membrane-spanning gA channels, these sequence positions are located near the lipid bilayer center (and subunit interface). The sequence substitutions at positions 3 and 5 were tested within the context of having either Gly or d-Ala at position 2, because d-Ala 2 causes the channel lifetimes to increase 3-fold relative to Gly2 [Mattice et al. (1995) Biochemistry 34, 6827]. Size-exclusion chromatograms and circular dichroism spectra show that the Ala → Ser replacements are well tolerated and have little effect on channel structure. In planar bilayers, the Ser-substituted gramicidins form well-defined channels, with cation conductances that are ～60% of those of the reference channels. The Ser-substituted channels are structurally equivalent to native gramicidin channels, as demonstrated by the formation of heterodimeric channels between a Ser-containing subunit and a native gramicidin subunit. These hybrid channels exhibit rectification, attributable to asymmetric placement of the single Ser hydroxyl group with respect to the bilayer center. Compared to the corresponding Ala-containing reference channels, the polar Ser residues decrease the analogues channel-forming potency by 3 orders of magnitude, indicating a substantial energetic penalty (～15 kJ/mol) for burying the polar Ser side chain in the bilayer hydrophobic core.
