Phosphorylated butirosin

Independently, Umezawa and coworkers and Brzezinska and Davies" found another enzyme, designated kanamycin phosphate transferase II or kanamycin-neomydn phosphate transferase II, in E. coli canning R factor, and it was found by the former authors that this enz)one also catalyzes the transfer of a phosphate group from adenosine 5 -triphos-phate to the 3 -hydroxyl group of the kanamycins, paromamine, neamine, neomycin, ribostamydn, and the butirosins. Therefore, kanamycin-neomycin phosphate transferase II differs from I in the following points II phosphorylates butirosin, but not lividomydn, whereas I phospho-rylates the latter, but not the former. 

Deoxykanamycin A (/ 73), in contrast to kanamydn A, is not phosphoryl-ated by 3 -0-phosphotransferase II, while the 3 -0-phosphotransferase I producing strains show resistance. Therefore, the 4 -hydroxyl group must be involved in the binding with the enzyme phosphotransferase II. By a study of the effect of the 4 -deoxygenation with neamine, l-N-HABA-neamine, ribostamycin and butirosin, it could be established that the inactivating reaction of the phosphotransferase II can only be prevented, if the 1 -amino function is substituted by an amino acid side chain (HABA). 

Phosphotransferase I phosphorylates not only the 3 -hydroxyl group, but also the 5"-hydroxyl function of lividomycin and 3, 4 -dideoxyribostamycin. The exclusive attack at the 3 -position of ribostamycin indicates that this position is steri-cally better located for the phosphate-transferring center of the enzyme than the 5"-hydroxyl group. A 5"-0-phosphotransferase that reacts also in this position of ribostamycin has been isolated f tom Pseudomonas. The interesting point of these S"-0-phosphorylations is that the 1-amino-HABA moiety in butirosin obviousiy... 

D-glucopyranosyl)-2-deoxystreptamine, neamine, paromamine, neomycin, paromomycin, ribostamycin, butirosin A, and butirosin B. Thus, the 3-amino-3-deoxy-D-gIucose moiety in the kanamycins and the d-ribose moiety in the butirosins are not involved in the reaction. Similar structural requirements for inhibitors of kanamycin-neomycin phosphate transferase of Pseudomonas aeruginosa, as later described (see p. 201), were also observed for kanamycin-neomycin phosphate transferase II. Phosphorylation of butirosin A was competitively inhibited by one tenth the concentration of 3, 4 -dideoxykanamycin B. 

Similar product ratios of deoxybutirosins (3-deoxy 2-deoxy = 5 1) have been observed by Okutani et The corresponding epimino derivative (335) of butirosin was prepared in 58% yield by nucleophilic attack of an amino group at C-2 displacing a 3-(9-phosphoryl leaving-group in a 5 1 BSA-MesSiCl mixture. 

Umezawa s group has reported the synthesis of 4 -deoxy-kanamycin via the coupling of an appropriately derivatized 6-amino-4,6-dideoxy-D-x j /n-hexosyI chloride with a streptamine derivative. The enzymic phosphorylation and antibacterial activity of the modified antibiotic were examined. Ribostamycin has been converted into butirosin B and its 3, 4 -dideoxy derivative, thus formally... 

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