Polypeptide antibiotics are a chemically diverse class of antibiotics containing nonprotein polypeptide chains. GoldBio’s polypeptides include bacitracin, colistin sulfate, colistin sodium methanosulfonate, gramicidin and polymyxin B. Gold Biotechnology ensures high quality reagents at affordable prices for research so that your research money can be used for what matters most.
Polypeptides
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Bacitrac99
        
          Catalog ID Size Pricing B-071-10 10 g $156.00 Show Product Details
product description
Bacitrac99 is the most pure form of bacitracin available, and should be used for the most sensitive applications and on the most sensitive cell lines since any impurities that might cause inhibition of resistant cell lines have been removed. In general, our USP Grade bacitracin will not adversely affect your cells and is suitable for most experiments.
Bacitracin is a cyclic polypeptide antibiotic isolated from Bacillus subtilis. It is made up of a variety of antimicrobial peptide fractions including A, A1, B, B1, B2, C, D, E, F, G, and X. This standard grade product is a mixture of these fractions, with bacitracin A exhibiting the most potent antimicrobial activity. Bacitracins B1 and B2 exhibit about 90% of the antimicrobial activity of bacitracin A when together. Other forms of bacitracin have not been studied extensively, but may have negligible antimicrobial properties.
Bacitracin targets the cell wall of gram-positive organisms such as Streptococcus pyogenes and Staphylococcus aureus. Bacitracin also functions as a useful tool to distinguish between group A and group B β-hemolytic Streptococcus species, which are susceptible and resistant, respectively.
Product Specifications
Catalog ID: B-071 CAS # : 1405-87-4 MW : 1422.69 g/mol Storage/handling : Store at 4°C. ViewPacks & PricingCatalog ID Size Pricing B-071-10 10 g $156.00 $156.00
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Bacitracin, USP Grade
        Catalog ID Size Pricing B-070-1 1 g $39.00 B-070-5 5 g $64.00 B-070-10 10 g $85.00 B-070-25 25 g $135.00 B-070-50 50 g $246.00 B-070-100 100 g $438.00 Show Product Details
product description
Bacitracin is a cyclic polypeptide antibiotic isolated from Bacillus subtilis. It is made up of a variety of antimicrobial peptide fractions including A, A1, B, B1, B2, C, D, E, F, G, and X. This standard grade product is a mixture of these fractions, with bacitracin A exhibiting the most potent antimicrobial activity. Bacitracins B1 and B2 exhibit about 90% of the antimicrobial activity of bacitracin A when together. Other forms of bacitracin have not been studied extensively, but may have negligible antimicrobial properties. Bacitracin is freely soluble in aqueous solution.
Bacitracin targets the cell wall of gram-positive organisms such as Streptococcus pyogenes and Staphylococcus aureus. Bacitracin also functions as a useful tool to distinguish between group A and group B β-hemolytic Streptococcus species, which are susceptible and resistant, respectively.
Product Specifications
Catalog ID: B-070 CAS # : 1405-87-4 MW : 1422.69 g/mol Storage/handling : Store at 4°C. ViewPacks & PricingCatalog ID Size Pricing B-070-1 1 g $39.00 B-070-5 5 g $64.00 B-070-10 10 g $85.00 B-070-25 25 g $135.00 B-070-50 50 g $246.00 B-070-100 100 g $438.00 $39.00 - $438.00
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Bactenecin
        Catalog ID Size Pricing B-305-1 1 mg $886.00 Show Product Details
product description
Bactenecin is a twelve residue antimicrobial peptide that is recognized by its disulfide linked cyclical structure. It lyses gram-negative bacteria by increasing permeability through binding lipopolysaccharides (LPS). The bactenecin/LPS conjugate forms a β-hairpin structures which integrate with the bacterial membrane, forming pores. Cytosol contents leak with pore formation and lysis occurs with higher bactenecin concentrations
Antibiotics are often used in clinical in vitro tests known as antimicrobial susceptibility tests or ASTs to determine their efficacy against certain bacterial species. They are tested against gram-negative and gram-positive bacteria using panels, discs, and MIC strips by medical microbiologists. ASTs decrease the risk of using an antibiotic against bacteria exhibiting resistance to it, and the results are used in clinical settings to determine which antibiotic(s) to prescribe for various infections.
Product Specifications
Catalog ID: B-305 CAS # : 116229-36-8 MW : 1.48 kDa Storage/handling : Store desiccated at -20°C. ViewPacks & PricingCatalog ID Size Pricing B-305-1 1 mg $886.00 $886.00
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Cecropin A
        Catalog ID Size Pricing C-285-1 1 mg $342.00 Show Product Details
product description
Cecropin A is a 37 amino acid chain that functions as an antibacterial and anti-cancer peptide. It is characterized by two alpha helices and has been researched because of the low cytotoxicity produced. Cecropin A produces synergistic effects with some chemotherapeutic agents, enhancing cytotoxic activity.
Cecropin A has been shown to cause bacterial and cancerous cell death by insertion into the cellular membrane due to amphiphilic N-terminal residues. In low lipid to peptide membrane component ratios, cecropin A will form ion channels that will disrupt metabolic gradients and lead to cell death. With high membrane peptide concentrations, cecropin A was observed to aggregate membrane peptides and break the membrane into fragments.
Product Specifications
Catalog ID: C-285 CAS # : 80451-04-3 MW : ~4 kDa Storage/handling : Store desiccated at -20°C. ViewPacks & PricingCatalog ID Size Pricing C-285-1 1 mg $342.00 $342.00
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Cecropin B
        Catalog ID Size Pricing C-625-1 1 mg $179.00 Show Product Details
product description
Cecropin B is a 35 amino acid chain that functions as an antibacterial and anti-cancer peptide. It is characterized by two alpha helices and has been researched because of the low cytotoxicity produced. Cecropin B has been shown to produce in vivo cytotoxic effects against stomach carcinomas. It has also been used to synthesize derivatives with activity against other cancer cell lines.
Cecropin B has been shown to cause bacterial and cancerous cell death by insertion into the cellular membrane, which is due to amphiphilic N-terminal residues. In low lipid to peptide membrane component ratios, cecropin B will form ion channels that will disrupt metabolic gradients and lead to cell death. With high membrane peptide concentrations, cecropin B was observed to aggregate membrane peptides and break the membrane into fragments.
Product Specifications
Catalog ID: C-625 CAS # : 80451-05-4 MW : 3.84 kDa Storage/handling : Store desiccated at -20°C. ViewPacks & PricingCatalog ID Size Pricing C-625-1 1 mg $179.00 $179.00
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Cecropin P1, porcine
        Catalog ID Size Pricing C-241-1 1 mg $342.00 Show Product Details
product description
Cecropin P1, porcine is a 31 amino acid antibacterial protein that can be isolated from pigs. Cecropin P1 is used as an antibacterial, antifungal and anti-cancer compound. The wide ranging effects of cecropin P1 are properties of its amphipathic N-terminal, lipophilic C-terminal and alpha helical structure. With these structural characteristics, cecropin P1 can bind to the membranes of pathogens and cancerous cells. Cecropin P1 then is inserted into the membrane of the respective cell and disrupts lipid bilayer cohesion, causing rapid membrane degradation and cell lysis.
Product Specifications
Catalog ID: C-241 CAS # : 125667-96-1 MW : 3.34 kDa Storage/handling : Store desiccated at -20°C. ViewPacks & PricingCatalog ID Size Pricing C-241-1 1 mg $342.00 $342.00
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Colistin Sodium Methanesulfonate
        Catalog ID Size Pricing C-920-1 1 g $144.00 C-920-5 5 g $554.00 C-920-10 10 g $1,068.00 Show Product Details
product description
Colistin is a polymyxin antibiotic effective against gram-negative bacteria. It has been used to permeabilize bacterial cell membranes and to study mannose-resistant haemagglutination. It has also been implicated in researching effective treatment for P. aeruginosa infections.
Colistin functions by targeting cell membranes and altering their permeability. Colistin sodium methanesulfonate (CMS) is considered an inactive prodrug, which means it is inactive until converted into colistin by cellular enzymes. GoldBio also offers Colistin sulfate (colistin), the end product of CMS, which does not require molecular conversion for antimicrobial properties.
Product Specifications
Catalog ID: C-920 CAS # : 8068-28-8 MW : 1759.90 g/mol Grade : MOLECULAR BIOLOGY GRADE Storage/handling : Store at 4°C. ViewPacks & PricingCatalog ID Size Pricing C-920-1 1 g $144.00 C-920-5 5 g $554.00 C-920-10 10 g $1,068.00 $144.00 - $1,068.00
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Colistin Sulfate, USP Grade
        Catalog ID Size Pricing C-921-1 1 g $31.00 C-921-5 5 g $64.00 C-921-25 25 g $194.00 C-921-100G 100 g $482.00 Show Product Details
product description
Colistin is a cyclic polypeptide antibiotic of the polymyxin family. It targets the cell membrane of bacteria, which ultimately leads to an altered cell permeability and cell death. It primarily targets gram-negative bacteria. Colistin has been used to study mannose-resistant haemagglutination, antibiotic resistance, and nephrotoxicity.
Colistin sulfate (colistin) is the end product of Colistin Sodium Methanesulfonate (CMS) and does not require molecular conversion for antimicrobial properties.
Product Specifications
Catalog ID: C-921 CAS # : 1264-72-8 MW : 2801.26 g/mol Storage/handling : Store at 4°C. ViewPacks & PricingCatalog ID Size Pricing C-921-1 1 g $31.00 C-921-5 5 g $64.00 C-921-25 25 g $194.00 C-921-100G 100 g $482.00 $31.00 - $482.00
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Enramycin
        
          Catalog ID Size Pricing E-610-10 10 mg $208.00 Show Product Details
product description
Enramycin is a polypeptide antibiotic that displays strong activity against gram positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). It is produced by the fungus Streptomyces fungicidus as Enramycin A (EA) and Enramycin B (EB), with this product containing an approximate 70:30 ratio of EA to EB. Enramycin has been effective against antibiotic resistant bacteria by inhibiting peptidoglycan synthesis for bacterial cell walls.
Enramycin has been proposed to halt peptidoglycan synthesis by inhibiting transferase enzyme MurG or by inhibiting transglycosylase activity. Both inhibitory pathways entail enramycin binding to peptidoglycan precursors in a cell wall synthesis pathway. Some studies have shown that enramycin binds the precursor Lipid I and inhibits MurG. Enramycin has also been shown to bind the Lipid II and prevent transglycosylation of the precursor by tranglycosylases.
Antibiotics are often used in clinical in vitro tests known as antimicrobial susceptibility tests or ASTs to determine their efficacy against certain bacterial species. They are tested against gram-negative and gram-positive bacteria using panels, discs, and MIC strips by medical microbiologists. ASTs decrease the risk of using an antibiotic against bacteria exhibiting resistance to it, and the results are used in clinical settings to determine which antibiotic(s) to prescribe for various infections.
Product Specifications
Catalog ID: E-610 CAS # : 11115-82-5 Storage/handling : Store at -20°C. ViewPacks & PricingCatalog ID Size Pricing E-610-10 10 mg $208.00 $208.00
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Polymyxin B Sulfate
        Catalog ID Size Pricing P-740-10 10 MU $135.00 P-740-100 100 MU $518.00 Show Product Details
product description
Polymyxin B sulfate is a polypeptide antibiotic mixture of B1, B2, and B3 polymyxins. Each of these fractions vary by a fatty acid group and exhibit marginal MIC differences when compared. Polymyxin B is most effective against gram-negative bacteria. It has been shown to work against Pseudomonas aeruginosa, Pseudomonas viridiflava, and Erwinia carotovora. Polymyxin B is freely soluble in aqueous solution.
Product Specifications
Catalog ID: P-740 CAS # : 1405-20-5 MW : 1385.61 g/mol Grade : MOLECULAR BIOLOGY GRADE Storage/handling : Store at 4°C. ViewPacks & PricingCatalog ID Size Pricing P-740-10 10 MU $135.00 P-740-100 100 MU $518.00 $135.00 - $518.00