Mycobacteria

Antituberculin Agents. Rifampin [13292-46-17, a semisynthetic derivative of rifamycin SV, is a most valuable dmg for treatment of tuberculosis, an infection caused by mycobacteria, leprosy, and an expanding range of other infections (23). Cycloserine [64-41-7] has been used to a limited extent for treatment of tuberculosis as a reserve dmg. Although cycloserine inhibits bacteria by interfering with their cell wall biosynthesis, it has toxic side effects in humans in the form of neurotoxicity. Capreomycin [11003-38-6] and to a much lesser extent viomycin [32988-50-4] both of which are peptides, have also been used for treatment of this disease. 

Pasteurization, the heating of certain fluids, frequentiy milk or dairy products (see Milk and milk products), destroys potentially harmful organisms such as mycobacteria, M. tuberculosis M. bovis or M. avium. Pasteurization, carried out at 62°C for 30 min or at 72°C for 15 s, is not a sterilization procedure. 

Activity against gram-positive bacteria = P gram-negative bacteria = N mycobacteria = M fungi = F tumors = T and viruses = V. Only peptides not discussed in the text of this article are given references. 

Lysol consists of a mixture of the three cresol isomers solubilized using a soap prepared from linseed oil and potassium hydroxide, to form a clear solution on dilution. Most vegetative pathogens, including mycobacteria, are killed in 15 minutes by 0.3—0.6% lysol. Lysol has a phenol coefficient of 2. Bacterial spores are very resistant. Lysol is also the name of a proprietary product, the formula of which has changed over the years other phenols have been substituted for the cresols. 

Sulfurmycin B (active again.st Gram-positive bacteria, mycobacteria, and tumors)... 

Mycobacteria (whole organisms peptidoglycans polysaccharides lipoarabinomannan)... 

Hongmanee P., Stender H., Rasmussen O.F. Evaluation of a fluorescence in situ hybridization assay for differentiation between tuberculous and nontuberculous Mycobacterium species in smears of Low-enstein-Jensen and mycobacteria growth indicator tube cultures using peptide nucleic acid probes. J. Clin. Microbiol. 2001 39 1032-1035. 

In the peptidoglycan from some mycobacteria, the muramic acid is A -gly-colylated, not A-acetylated. As already mentioned, ester-linked lactic acid... 

Fig. 15.—Sequence of One of the Oligosaccharides Obtained from the Trehalose-containing Glycolipids of Mycobacteria kansasii. [Cleavage positions in the positive-ion mode (Pathway C, Section IV,2) are shown above the sequence. Cleavage positions in the negative-ion mode (Pathway B, Section IV,2) are shown below the sequence.

Mycolic acid and arabinogalactan synthesis in mycobacteria 4.5 5-Fluorocytosine... 

The cell walls of mycobacteria contain three structures peptidoglycan, an arabinogalactan polysaccharide and long chain hydroxy fatty acids (mycolic acids) which are all covalently linked. Additional non-covalently attached lipid components found in the wall include glycolipids, various phospholipids and waxes. The lipid-rich nature of the mycobacterial wall is responsible for the characteristic acid-fastness on staining and serves as a penetration barrier to many antibiotics. Isoniazid and ethambutol have long been known as specific antimycobacterial agents but their mechanisms of action have only recently become more clearly understood. 

The antimicrobial action of ethambutol, like that of isoniazid, is specific for mycobacteria, suggesting a target in the unique components of the mycobacterial cell wall. Cells treated with ethambutol accumulate an isoprenoid intermediate, decaprenyl-arabinose which is the source ofarabinose in the arabinogalactan polymer. This suggests that ethambutol blocks assembly of the arabinogalactan through inhibition of an arabinosyl transferase enzyme. 

Musser J.M. (1995) Antimicrobial agent resistance in mycobacteria molecular genetic insights. Clin Microbiol Rev, 8, 496-514. 

Class of compound Activity against Bacterial Mycobacteria spores Generai ievei of antibacteriai activity... 

Of the other peroxygen compounds with antimicrobial activity, potassium monoperoxysulphate is the main product marketed for disinfectant use. It is used for body fluid spillages and equipment contaminated with body fluids, but its activity against mycobacteria and some viruses is limited. 

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