Hotta K, Morioka M, Okami Y
National Institute of Health, Tokyo, Japan.
J Antibiot (Tokyo). 1989 May;42(5):745-51. doi: 10.7164/antibiotics.42.745.
The profile of bioconversion products of istamycin (IS) components by a blocked IS mutant of Streptomyces tenjimariensis that lost IS-productivity suggested a possible biosynthetic pathway of IS similar to that of fortimicin (FT) by Micromonospora olivasterospora. Both organisms are resistant to the antibiotics produced by each other. Based on these similarities, they were examined for their capability to convert an FT-intermediate (FT-B) and IS-intermediates (IS-A0 and -B0) through their biosynthetic pathways. S. tenjimariensis formed 1-epi-FT-B, 2''-N-formimidoyl-FT-A (= dactimicin) and 1-epidactimicin (a new antibiotic) from FT-B. On the other hand, M. olivasterospora converted IS-A0 and -B0 to 2''-N-formimidoyl-IS-A (= IS-A3) and -B (= IS-B3), respectively. Thus, the similarity in antibiotic biosynthesis was confirmed between these FT-group antibiotic-producing organisms. It was also found that the major fermentation product of M. olivasterospora is not FT-A (astromicin) but dactimicin.
天城链霉菌的一个失去制霉素（IS）生产能力的阻断型IS突变体对IS组分的生物转化产物谱表明，IS可能的生物合成途径类似于橄榄小单孢菌合成福提霉素（FT）的途径。这两种生物对彼此产生的抗生素均具有抗性。基于这些相似性，研究了它们通过生物合成途径转化FT中间体（FT-B）以及IS中间体（IS-A0和-B0）的能力。天城链霉菌从FT-B形成了1-表-FT-B、2''-N-甲脒基-FT-A（=达地米星）和1-表达地米星（一种新抗生素）。另一方面，橄榄小单孢菌分别将IS-A0和-B0转化为2''-N-甲脒基-IS-A（=IS-A3）和-B（=IS-B3）。因此，证实了这些生产FT类抗生素的生物在抗生素生物合成方面具有相似性。还发现橄榄小单孢菌的主要发酵产物不是FT-A（阿司米星）而是达地米星。
