ID 4.3.2.6 DE gamma-L-glutamyl-butirosin B gamma-glutamyl cyclotransferase. CA gamma-L-glutamyl-butirosin B = 5-oxo-L-proline + butirosin B. CC -!- The enzyme catalyzes the last step in the biosynthesis of the CC aminoglycoside antibiotic butirosin B. CC -!- The enzyme acts as a cyclotransferase, cleaving the amide bond via CC transamidation using the alpha-amine of the terminal gamma-L- CC glutamate of the side chain, releasing it as the cyclic 5-oxoproline. DR Q4H4F0, BTRG_NIACI ; //