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Interferes with Cell Membrane Permeability (Ionophores)

Polymyxin B and colistin (polymyxin E) disrupt the cell membrane integrity of Gram-negative bacteria by binding to membrane phospholipids. Eukaryotic cell membranes have phospholipids similar to Gram-negative bacteria, so the polymyxins are most often used clinically as topical antibiotics.

In contrast, the ionophore antibiotics such as monensin and valinomycin tend to be more active against Gram-positive bacteria, which lack the outer cell membranes. Monensin is an ionophore that forms monovalent ion channels in the cell wall of Gram-positive bacteria and allows the free movement of K+ and Na+ ions along their concentration gradients. Valinomycin is a selective K+ ionophore that triggers mitochondrial transition by facilitating the transport of K+ across the mitochondrial membrane. By altering the intracellular cationic environment of the cell, these agents uncouple mitochondrial oxidative metabolism and inhibit cell growth.

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100105 A23187, Free Acid, Streptomyces chartreusensis - CAS 52665-69-7 - Calbiochem A mobile ion-carrier that forms stable complexes with divalent cations.
100106 A23187, Mixed Calcium-Magnesium Salt - Calbiochem Useful in cell activation experiments when calcium dose-response data are not required.
100107 A23187, 4-Bromo- - CAS 76455-48-6 - Calbiochem Brominated analog of the widely used cation ionophore A23187. Non-fluorescent and therefore suitable for use in the presence of fluorescent or metal-chelating probes.
205535 CA 1001 - CAS 58801-34-6 - Calbiochem A neutral ionophore with extremely high selectivity for Ca2+ ions.
227013 CCR4 Antagonist - CAS 864289-85-0 - Calbiochem The CCR4 Antagonist, also referenced under CAS 864289-85-0, controls the biological activity of CCR4. This small molecule/inhibitor is primarily used for Membrane applications.
368020 Gramicidin A, High Purity, Bacillus brevis - CAS 11029-61-1 - Calbiochem Gramicidin A, High Purity, Bacillus brevis, CAS 11029-61-1, is a naturally-occurring ion channel-forming pentadecapeptide. Causes K+/H+ exchange in mitochondria in a non-voltage dependent manner.
407950 Ionomycin, Free Acid, Streptomyces conglobatus - CAS 56092-81-0 - Calbiochem Ionomycin, Free Acid, Streptomyces conglobatus, CAS 56092-81-0, is an ionophore with high specificity for divalent cations. More effective than A23187 as a mobile ion carrier for Ca2+., Ionomycin, Free Acid, Streptomyces conglobatus, CAS 56092-81-0, is a highly specific for divalent cations and more effective than A23187 (Cat. No. 100105) as a mobile ion carrier for Ca2+.
407951 Ionomycin, Free Acid, Streptomyces conglobatus in Solution - CAS 56092-81-0 - Calbiochem
407952 Ionomycin, Calcium Salt, Streptomyces conglobatus - CAS 56092-82-1 - Calbiochem Ionomycin, Calcium Salt, Streptomyces conglobatus, CAS 56092-82-1, is useful in cell activation experiments when calcium dose-response data are not required.
407953 Ionomycin, Calcium Salt, Streptomyces conglobatus in Solution - Calbiochem Ionomycin, Calcium Salt, Streptomyces conglobatus, CAS 56092-82-1, is a 10 mM solution in DMSO. Useful in cell activation experiments when calcium dose-response data are not required., Useful in cell activation experiments when calcium dose-response data are not required. The solid form of this compound is also available.
475895 Monensin, Sodium Salt, High Purity - CAS 22373-78-0 - Calbiochem Polyether antibiotic that functions as a Na+ ionophore by forming stable complexes with monovalent cations that are able to cross the plasma membrane.
475897 Monensin Methyl Ester - Calbiochem A neutral analog of monensin.
475914 Nystatin, Streptomyces noursei - CAS 1400-61-9 - Calbiochem Nystatin, Streptomyces noursei, CAS 1400-61-9, is an antifungal antibiotic effective against yeast and mycoplasma. Acts as a cation-selective ionophore that exhibits selectivity for Na+., A polyene antifungal antibiotic effective against yeast and mycoplasma.
481990 Nigericin, Sodium Salt, Streptomyces hygroscopicus - CAS 28643-80-3 - Calbiochem Nigericin, Sodium Salt, Streptomyces hygroscopicus, CAS 28643-80-3, is an antibiotic K+ ionophore that disrupts the membrane potential and stimulates ATPase activity in mitochondria., Disrupts the membrane potential and stimulates ATPase activity in mitochondria.
563080-M Salinomycin Salinomycin reduces the proportion of cancer stem cells(CSC) by >100-fold relative to paclitaxel, a commonly used breast cancer chemotherapeutic drug.
569385 SQI-Pr - CAS 1022595-16-9 - Calbiochem Synthetic ionophore for sodium.
676377 Valinomycin, Streptomyces fulvissimus - CAS 2001-95-8 - Calbiochem A cyclododecadepsi-peptide ionophore antibiotic.
A4665 Alamethicin from Trichoderma viride ≥98% (HPLC)
A5361 Alamethicin, Ready Made Solution from Trichoderma viride 5 mg/mL in DMSO, sterile; 0.2 μm filtered
A3281 N-(6-Aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride
A2942 Amphotericin B solution 250 μg/mL in deionized water, sterile-filtered, BioReagent, suitable for cell culture
A4888 Amphotericin B from Streptomyces sp. ~80% (HPLC), powder
A2411 Amphotericin B from Streptomyces sp. BioReagent, suitable for cell culture, ~80% (HPLC)
A9528 Amphotericin B solubilized powder, γ-irradiated, BioXtra, suitable for cell culture
SRP3013 Beta D-4 human recombinant, expressed in E. coli, ≥98% (SDS-PAGE), ≥98% (HPLC), cell culture tested
SRP3011 Beta D-1 (36 aa) human recombinant, expressed in E. coli, ≥98% (SDS-PAGE), ≥98% (HPLC), cell culture tested
SRP3012 Beta D-1 (47 aa) human recombinant, expressed in E. coli, ≥98% (SDS-PAGE), ≥98% (HPLC), cell culture tested
21186 Calcium ionophore III Selectophore, function tested
C7522 Calcium Ionophore A23187 ≥98% (TLC), powder
C9275 Calcium Ionophore A23187 hemicalcium salt powder
C9400 Calcium Ionophore A23187 hemimagnesium salt
C6830 Cecropin A ≥97% (HPLC), powder
C1796 Cecropin B ≥97% (HPLC), powder
C7927 Cecropin P1 Porcine ≥95% (HPLC), powder
C6143 Chlorhexidine diacetate salt hydrate bis(biguanide) antimicrobial
C9394 Chlorhexidine digluconate solution 20% in H2O
C5241 Cinnamycin from Streptomyces cinnamoneus, ≥95% (HPLC)
C6019 Clotrimazole
33894 Clotrimazole VETRANAL, analytical standard
C4461 Colistin sulfate salt ≥15,000 U/mg
C1511 Colistin sodium methanesulfonate ~11,500 U/mg
27655 Colistin sodium methanesulfonate from Bacillus colistinus
D2043 Defensin HNP-1 human ≥80% (HPLC)
D6790 Defensin HNP-2 human ≥95% (HPLC)
E4632 Econazole nitrate salt
F9765 Filipin complex from Streptomyces filipinensis ≥70% (UV)
G5002 Gramicidin from Bacillus aneurinolyticus (Bacillus brevis) Linear polypeptide antibiotic complex. A mixture of gramicidins A, B, C, and D.
50845 Gramicidin A from Bacillus brevis ≥90% (HPLC)
50847 Gramicidin C from Bacillus brevis ~90% (HPLC)
I0634 Ionomycin calcium salt from Streptomyces conglobatus powder, ≥98% (HPLC)
I9657 Ionomycin from Streptomyces conglobatus ≥98% (HPLC)
I1774 Iturin A from Bacillus subtilis ≥95% (HPLC)
92301 Listeria mono Selective Supplement I for microbiology
M7152 Magainin I ≥97% (HPLC)
M7402 Magainin II ≥97% (HPLC)
H3261 2-Mercaptopyridine N-oxide sodium salt ≥96%
63844 2-Mercaptopyridine N-oxide sodium salt ≥96.0% (NT)
M5273 Monensin sodium salt 90-95% (TLC)
46468 Monensin sodium salt hydrate VETRANAL, analytical standard
SMB00293 Mycosubtilin ≥90%
N1271 Narasin from Streptomyces auriofaciens ≥98% (HPLC)
N7143 Nigericin sodium salt ≥98% (TLC)
N5764 Nisin from Lactococcus lactis 2.5% (balance sodium chloride and denatured milk solids)
74155 Nonactin from Streptomyces sp., ≥97.0% (TLC)
N2286 Nonactin from Streptomyces griseus, ≥98% (function tested, HPLC)
SRP3126 NP-1 human recombinant, expressed in E. coli, ≥98% (SDS-PAGE), ≥98% (HPLC), cell culture tested
N3503 Nystatin ≥4,400 USP units/mg
N6261 Nystatin powder, BioReagent, suitable for cell culture
N4014 Nystatin powder, γ-irradiated, BioXtra, suitable for cell culture
N1638 Nystatin Suspension suspension, 10,000 unit/mL in DPBS, aseptically processed, BioReagent, suitable for cell culture
P0098 Pediocin from Pediococcus acidilactici ≥95% (HPLC), buffered aqueous solution
P0053 PGLa
P9625 Phenazine methosulfate ≥90% (UV)
P9703 Pimaricin from Streptomyces chattanoogensis, ≥95% (HPLC)
P0440 Pimaricin preparation ~2.5%, aqueous suspension
81271 Polymyxin B solution 1 mg/mL in H2O, analytical standard
P0972 Polymyxin B sulfate meets USP testing specifications, powder
P1004 Polymyxin B sulfate salt
P4932 Polymyxin B sulfate salt powder, BioReagent, suitable for cell culture
P4119 Polymyxin B sulfate salt Biotechnology Performance Certified
P4668 Praziquantel anthelminic, neurogenic
46648 Praziquantel VETRANAL, analytical standard
S4526 Salinomycin from Streptomyces albus, ≥98% (HPLC)
S6201 Salinomycin, Ready Made Solution from Streptomyces albus, ≥98% (HPLC)
S3523 Surfactin from Bacillus subtilis, ≥98% (HPLC and TLC)
S6946 Syringomycin E from Pseudomonas syringae B-301D, >95% (HPLC), solution
03907 Tioconazole 97%
V0627 Valinomycin ≥98% (TLC), ≥90% (HPLC), solid
94675 Valinomycin ≥98.0% (TLC)
V3639 Valinomycin Ready Made Solution, ~1 mg/mL in DMSO, 0.2 μm filtered