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Antipseudomonal Penicillins
The extended-spectrum penicillins are a group of antibiotics that have the widest antibacterial spectrum of all penicillins. Some sources identify them with antipseudomonal penicillins, others consider these types to be distinct. This group includes the carboxypenicillins and the ureidopenicillins. Aminopenicillins, in contrast, do not have activity against ''Pseudomonas'' species, as their positively charged amino group does not hinder degradation by bacterially produced beta-lactamases. Products *Ureidopenicillins **Azlocillin **Mezlocillin **Piperacillin *Carboxypenicillins **Ticarcillin (generally in the combination ticarcillin/clavulanic acid) **Carbenicillin *Mecillinam Mecillinam (INN) or amdinocillin (USAN) is an extended-spectrum penicillin antibiotic of the amidinopenicillin class that binds specifically to penicillin binding protein 2 (PBP2), and is only considered to be active against Gram-negative bacteria ... See also * ''Pseudomonas aeruginosa'' § Treatment Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of such infections. They may either kill or inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the common cold or influenza; drugs which inhibit viruses are termed antiviral drugs or antivirals rather than antibiotics. Sometimes, the term ''antibiotic''—literally "opposing life", from the Greek roots ἀντι ''anti'', "against" and βίος ''bios'', "life"—is broadly used to refer to any substance used against microbes, but in the usual medical usage, antibiotics (such as penicillin) are those produced naturally (by one microorganism fighting another), whereas non-antibiotic antibacterials (such as sulfonamides and antise ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mezlocillin
Mezlocillin is a broad-spectrum penicillin antibiotic. It is active against both Gram-negative and some Gram-positive bacteria. Unlike most other extended spectrum penicillins, it is excreted by the liver, therefore it is useful for biliary tract infections, such as ascending cholangitis. Mechanism of action Like all other beta-lactam antibiotics, mezlocillin inhibits the third and last stage of bacterial cell wall synthesis by binding to penicillin binding proteins. This ultimately leads to cell lysis. Susceptible organisms Gram-negative *''Bacteroides'' spp., including ''B. fragilis'' *''Enterobacter'' spp. *''Escherichia coli'' *''Haemophilus influenzae'' *''Klebsiella'' species *'' Morganella morganii'' *'' Neisseria gonorrhoeae'' *''Proteus mirabilis'' *''Proteus vulgaris'' *'' Providencia rettgeri'' *''Pseudomonas'' spp., including '' P. aeruginosa'' *''Serratia marcescens'' Gram-positive *''Enterococcus faecalis'' *'' Peptococcus'' spp.'' *''Peptostreptococcus'' spp. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mecillinam
Mecillinam (INN) or amdinocillin (USAN) is an extended-spectrum penicillin antibiotic of the amidinopenicillin class that binds specifically to penicillin binding protein 2 (PBP2), and is only considered to be active against Gram-negative bacteria. It is used primarily in the treatment of urinary tract infections, and has also been used to treat typhoid and paratyphoid fever. Because mecillinam has very low oral bioavailability, an orally active prodrug was developed: pivmecillinam. Medical uses Mecillinam is used in the treatment of infections due to susceptible gram-negative bacteria, especially urinary tract infections which are most commonly caused by ''Escherichia coli''. Mecillinam is active against most pathogenic Gram-negative bacteria, except ''Pseudomonas aeruginosa'' and some species of ''Proteus''. Retrieved on August 31, 2008. Freely available with registration. Several studies have also found it to be as effective as other antibiotics for treating '' Staphylococcu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbenicillin
Carbenicillin is a bactericidal antibiotic belonging to the carboxypenicillin subgroup of the penicillins. It was discovered by scientists at Beecham and marketed as Pyopen. It has Gram-negative coverage which includes ''Pseudomonas aeruginosa'' but limited Gram-positive coverage. The carboxypenicillins are susceptible to degradation by beta-lactamase enzymes, although they are more resistant than ampicillin to degradation. Carbenicillin is also more stable at lower pH than ampicillin. Pharmacology The antibiotic is highly soluble in water and is acid-labile. A typical lab working concentration is 50 to 100 µg per ml. It is a semi-synthetic analogue of the naturally occurring benzyl-penicillin. Carbenicillin at high doses can cause bleeding. Use of carbenicillin can cause hypokalemia by promoting potassium loss at the distal convoluted tubule of the kidney. In molecular biology, carbenicillin may be preferred as a selecting agent (see Plasmid stabilisation technology) b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ticarcillin/clavulanic Acid
Ticarcillin/clavulanic acid, or co-ticarclav, is a combination antibiotic consisting of ticarcillin, a β-lactam antibiotic, and clavulanic acid, a β-lactamase inhibitor. This combination results in an antibiotic with an increased spectrum of action and restored efficacy against ticarcillin-resistant bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ... that produce certain β-lactamases. References Combination antibiotics {{antibiotic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ticarcillin
Ticarcillin is a carboxypenicillin. It can be sold and used in combination with clavulanate as ticarcillin/clavulanic acid. Because it is a penicillin, it also falls within the larger class of beta-lactam antibiotics. Its main clinical use is as an injectable antibiotic for the treatment of Gram-negative bacteria, particularly ''Pseudomonas aeruginosa'' and Proteus vulgaris. It is also one of the few antibiotics capable of treating '' Stenotrophomonas maltophilia'' infections. It is provided as a white or pale-yellow powder. It is highly soluble in water, but should be dissolved only immediately before use to prevent degradation. It was patented in 1963. Mechanism of action Ticarcillin's antibiotic properties arise from its ability to prevent cross-linking of peptidoglycan during cell wall synthesis, when the bacteria try to divide, causing cell death. Ticarcillin, like penicillin, contains a β-lactam ring that can be cleaved by beta-lactamases, resulting in inactivatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxypenicillin
The carboxypenicillins are a group of antibiotics. They belong to the penicillin family and comprise the members carbenicillin and ticarcillin. Chemical structure The carboxypenicillins feature the beta-lactam backbone of all penicillins but also feature a carboxylic acid or carboxylic acid ester group in the variable side-chain. Spectrum The carboxypenicillins exhibit activity against Gram negative organisms including ''Pseudomonas aeruginosa'' and ''Proteus'' species. They are inactive against certain Gram positive pathogens such as ''Staphylococcus aureus'', ''Enterococcus faecalis'', and '' L. monocytogenes''. The carboxypenicillins are beta-lactamase sensitive. See also * Aminopenicillin The aminopenicillins are a group of antibiotics in the penicillin family that are structural analogs of ampicillin (which is the 2- amino derivative of benzylpenicillin, hence the name). Like other penicillins and beta-lactam antibiotics, they c ... References {{Cell wall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piperacillin
Piperacillin is a broad-spectrum β-lactam antibiotic of the ureidopenicillin class. The chemical structure of piperacillin and other ureidopenicillins incorporates a polar side chain that enhances penetration into Gram-negative bacteria and reduces susceptibility to cleavage by Gram-negative beta lactamase enzymes. These properties confer activity against the important hospital pathogen ''Pseudomonas aeruginosa''. Thus piperacillin is sometimes referred to as an "anti-pseudomonal penicillin". When used alone, piperacillin lacks strong activity against the Gram-positive pathogens such as '' Staphylococcus aureus'', as the beta-lactam ring is hydrolyzed by the bacteria's beta-lactamase. It was patented in 1974 and approved for medical use in 1981. Piperacillin is most commonly used in combination with the beta-lactamase inhibitor tazobactam ( piperacillin/tazobactam), which enhances piperacillin's effectiveness by inhibiting many beta lactamases to which it is susceptible. Howev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azlocillin
Azlocillin is an acyl ampicillin antibiotic with an extended spectrum of activity and greater ''in vitro'' potency than the carboxy penicillins. Azlocillin is similar to mezlocillin and piperacillin. It demonstrates antibacterial activity against a broad spectrum of bacteria, including '' Pseudomonas aeruginosa'' and, in contrast to most cephalosporins, exhibits activity against enterococci. Spectrum of bacterial susceptibility Azlocillin is considered a broad spectrum antibiotic and can be used against a number of Gram positive and Gram negative bacteria. The following represents MIC susceptibility data for a few medically significant organisms. * ''Escherichia coli'' 1 μg/mL – 32 μg/mL * ''Haemophilus'' spp. 0.03 μg/mL – 2 μg/mL * ''Pseudomonas aeruginosa'' 4 μg/mL – 6.25 μg/mL Synthesis An interesting alternative synthesis of azlocillin involves activation of the substituted phenylglycine analogue 1 with 1,3-dimethyl-2-chloro-1-imidazolinium chlorid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penicillin
Penicillins (P, PCN or PEN) are a group of β-lactam antibiotics originally obtained from '' Penicillium'' moulds, principally '' P. chrysogenum'' and '' P. rubens''. Most penicillins in clinical use are synthesised by P. chrysogenum using deep tank fermentation and then purified. A number of natural penicillins have been discovered, but only two purified compounds are in clinical use: penicillin G (intramuscular or intravenous use) and penicillin V (given by mouth). Penicillins were among the first medications to be effective against many bacterial infections caused by staphylococci and streptococci. They are still widely used today for different bacterial infections, though many types of bacteria have developed resistance following extensive use. 10% of the population claims penicillin allergies but because the frequency of positive skin test results decreases by 10% with each year of avoidance, 90% of these patients can tolerate penicillin. Additionally, those wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ureidopenicillin
The ureidopenicillins are a group of penicillins which are active against ''Pseudomonas aeruginosa''. There are three ureidopenicillins in clinical use: *Azlocillin *Piperacillin *Mezlocillin They are mostly ampicillin derivatives in which the amino acid side chain has been converted to a variety of cyclic ureas. It is speculated that the added side chain mimics a longer segment of the peptidoglycan chain, more than ampicillin, and thus would bind more easily to the penicillin-binding proteins. Ureidopenicillins are not resistant to beta-lactamases. They are used parenterally, and are particularly indicated in infections caused by Gram-negative bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am .... References {{Cell wall disruptive antibiotics Penicillins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta-lactamase
Beta-lactamases, (β-lactamases) are enzymes () produced by bacteria that provide multi-resistance to beta-lactam antibiotics such as penicillins, cephalosporins, cephamycins, monobactams and carbapenems ( ertapenem), although carbapenems are relatively resistant to beta-lactamase. Beta-lactamase provides antibiotic resistance by breaking the antibiotics' structure. These antibiotics all have a common element in their molecular structure: a four-atom ring known as a beta-lactam (β-lactam) ring. Through hydrolysis, the enzyme lactamase breaks the β-lactam ring open, deactivating the molecule's antibacterial properties. Beta-lactam antibiotics are typically used to target a broad spectrum of gram-positive and gram-negative bacteria. Beta-lactamases produced by gram-negative bacteria are usually secreted, especially when antibiotics are present in the environment. Structure The structure of a ''Streptomyces'' serine β-lactamase (SBLs) is given by . The alpha-beta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
