Bacteria Antitubercular

Mechanism of Action An antitubercular whose exact mechanism of action is unknown. Therapeutic Effect Either bacteriostatic or bactericidal, depending on the drug s concentration at the infection site and the susceptibility of infecting bacteria. Pharmacokinetics Nearly completely absorbed from GI tract. Protein binding 5%-10%. Excreted in urine. Half-life 9-23 hr. 

Polyketide and non-ribosomal peptides produced by bacteria and fungi often attain the conformations that establish biological activity by cychzation constraints introduced by tailoring enzymes. This includes heterocychzation of cysteines, serines and threonines in non-ribosomal peptides. The second cychzation constraint is macrocychzation in polyketides, such as the above-mentioned antibiotic erythromycin and the antitumor epothilones. Regio- and stereospecific macrocychzation usuaUy occurs at the end of the polyketide and non-ribosomal peptide assembly hnes during chain release by thioesterase domains [49]. However, in the case of antibiotics of the ansamycin class, like the antitubercular drug rifamycin, the final... 

Parent strains of certain bacteria, e.g., antibiotic-resistant or antitubercular-drug-resistant strains, can be differentiated from nonresistant substrains. The spores of phytopathogenic fungi can be differentiated by means of their spectra. Viruses can also be differentiated. 

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