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Structural characterization of AtmS13, a putative sugar aminotransferase involved in indolocarbazole AT2433 aminopentose biosynthesis.

ABSTRACT: AT2433 from Actinomadura melliaura is an indolocarbazole antitumor antibiotic structurally distinguished by its unique aminodideoxypentose-containing disaccharide moiety. The corresponding sugar nucleotide-based biosynthetic pathway for this unusual sugar derives from comparative genomics where AtmS13 has been suggested as the contributing sugar aminotransferase (SAT). Determination of the AtmS13 X-ray structure at 1.50-Å resolution reveals it as a member of the aspartate aminotransferase fold type I (AAT-I). Structural comparisons of AtmS13 with homologous SATs that act upon similar substrates implicate potential active site residues that contribute to distinctions in sugar C5 (hexose vs. pentose) and/or sugar C2 (deoxy vs. hydroxyl) substrate specificity.

SUBMITTER: Singh S

PROVIDER: S-EPMC4570032 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Structural characterization of AtmS13, a putative sugar aminotransferase involved in indolocarbazole AT2433 aminopentose biosynthesis.

Singh Shanteri S Kim Youngchang Y Wang Fengbin F Bigelow Lance L Endres Michael M Kharel Madan K MK Babnigg Gyorgy G Bingman Craig A CA Joachimiak Andrzej A Thorson Jon S JS Phillips George N GN

Proteins 20150701 8

AT2433 from Actinomadura melliaura is an indolocarbazole antitumor antibiotic structurally distinguished by its unique aminodideoxypentose-containing disaccharide moiety. The corresponding sugar nucleotide-based biosynthetic pathway for this unusual sugar derives from comparative genomics where AtmS13 has been suggested as the contributing sugar aminotransferase (SAT). Determination of the AtmS13 X-ray structure at 1.50-Å resolution reveals it as a member of the aspartate aminotransferase fold t ...[more]

PMID: 26061967

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