Penicillin

4 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  penicillin \pen`i*cil"lin\ (p[e^]n`[i^]*s[i^]l"l[i^]n), n. [From
     Penicillium, the fungus genus from which it was first
     isolated.] (Chem.)
     Any of a variety of substances having a structure containing
     a beta-lactam ring fused to a thiirane ring, to which a
     carboxyl group is attached, but most commonly interpreted as


     {benzyl penicillin}. They are notable as powerful
     antibacterial agents of relatively low toxicity which have
     found extensive use in medicine for treating bacterial
     infections. They are categorized as one of the classes of
     beta-lactam antibiotic. They are produced naturally by some
     fungi and bacteria, and industrial production processes
     almost invariably start from some form of the penicillin
     nucleus produced by fermentation of microorganisms. The
     fermentation products are then chemically modified to produce
     derivatives of enhanced potency, safety, or antibacterial
     spectrum. The first penicillin to see extensive use
     clinically (during World War II) was {penicillin G}, also
     called {benzypenicillin}, and commonly simply "penicillin".
     [PJC]
  
     Note: [hand]The characteristic portion of the structure
           characterizing a penicillin is the bicyclic structure
           3,3-Dimethyl-7-oxo-4-thia-1-azabicylo[3.2.0]heptane-2-carboxylic
           acid. The different penicillins have varying acyl
           groups forming an amide bond with a nitrogen attached
           to the 6-carbon of this nucleus. This distinguishes it
           from the other classes of beta-lactam antibiotic, the
           {cephalosporins}, {thienamycins} and {sulfazecin}.
           [PJC]

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Lactam \Lac"tam\, n. [Lactone + amido.] (Chem.)
     One of a series of anhydrides of an amido type, analogous to
     the lactones, as oxindol; a cyclic amide.
     [1913 Webster]
  
     {beta-lactam} or {[beta]-lactam},
     (a) a lactam in which the amide bond is contained within a
         four-membered ring, which includes the amide nitrogen and
         the carbonyl carbon.
     (b) an antibiotic containing a beta-lactam, such as a
         {penicillin}, {cephalosporin}, or {carbapenem}; also
         called a {beta-lactam antibiotic}. [informal, laboratory
         slang]
         [PJC]

From WordNet (r) 2.0 [wn]:

  penicillin
       n : any of various antibiotics obtained from penicillium molds
           (or produced synthetically) and used in the treatment of
           various infections and diseases

From Moby Thesaurus II by Grady Ward, 1.0 [moby-thes]:

  23 Moby Thesaurus words for "penicillin":
     Chloromycetin, Terramycin, actinomycin, amphotericin, bacitracin,
     carbomycin, chlortetracycline, cloxacillin, dihydrostreptomycin,
     erythromycin, fradicin, gramicidin, griseofulvin, methicillin,
     mitomycin, streptomycin, streptothricin, subtilin, tetracycline,
     tylocin, tyrothricin, vancomycin, viomycin