Mode blasticidin

There are two commercial fungicides, the antibiotics blasticidin S and kasugamycin, that act via the inhibition of protein biosynthesis (Figure 4.19). Blasticidin S is a fermentation product obtained from cultures of Streptomyces griseochromogenes, and has specific activity in the control of P. oryzae, similar to kasugamycin, a secondary metabolite of S. kasugaensis. However, much of the earlier work on mode of action was carried out using another antibiotic, cycloheximide. 

The mode of action of kasugamycin is similar to that of blasticidin S. It inhibits protein synthesis in fungi and bacteria. It inhibits binding of the aminoacyl-tRNA complex to the ribosome (Tanaka et al., 1966), but does not disturb the synthesis of nucleic acids. The inhibitory effect is considerably lower in the liver tissue of rats. The selectivity of toxicity may be due to the particular sensitivity to kasugamycin of the ribosomes of each type of organism. This may also explain the relatively rapid development of resistance to kasugamycin. 

Yamaguchi 1, Misato T. Active center and mode of reaction of blasticidin S deaminase. Agric Biol Chem 1985 49 3355-3361. 

The Fast atom bombardment (FAB)-m.s. of carbohydrates has been reviewed. FAB-m.s. has been used to characterise individual oligogalacturonic acids (in both the +ve and -ve ion modes). FAB-m.s. and mass-analyzed ion kinetic energy (MIKES) spectra were used to characterise components of peptide-nucleoside antibiotics including blasticidin S and mildomycin analogues.° From a FAB-... 

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