Biosynthesis of 2-Deoxystreptamine-containing Antibiotics in Streptoalloteichus hindustanus JCM 3268: Characterization of 2-Deoxy-scyllo-inosose Synthase

Abstract

A part of the new biosynthetic gene cluster for 2-deoxystreptamine-containing antibiotics was identified from Streptoalloteichus hindustanus. The alloH gene in the gene cluster was deduced to encode 2-deoxy-scyllo-inosose synthase and the expressed protein AlloH was confirmed to have this enzyme activity. Furthermore, biochemical properties of AlloH were studied. Keywords 2-deoxystreptamine biosynthetic genes, Streptoalloteichus hindustanus, 2-deoxy-scyllo-inosose synthase, kinetics Aminoglycosides are an important group of antibiotics in clinical use for a long time. Even today, new activities of aminoglycosides are being discovered; for example, the activity of arginine complexes against HIV [1,2]. Aminoglycosides are structurally oligosaccharides containing one of a small number of specific aminocyclitols and various amino sugars, which are connected together through the glycosidic bonds. Indeed, the biosynthetic enzymes

C3′‐Deoxygenation of Paromamine Catalyzed by a Radical S‐Adenosylmethionine Enzyme: Characterization of the Enzyme AprD4 and Its Reductase Partner AprD3

“…18,19 While no gene in the tobramycin cluster has been implicated in catalyzing C3′-deoxygenation, 14,15 recent investigations including gene knockout studies 20 into the apramycin and lividomycin B pathways have identified the AprD4/AprD3 and LivW/LivY pairs as likely candidates for the activity. For example, incorporation of the aprD4 and aprD3 genes into the kanamycin (see 6 ) producing strain S. kanamyceticus led to the isolation of 3′-deoxykanamycins (e.g., 7 ), 19 which are not normally produced.…”

“…14,15,18 The radical SAM enzymes are characterized by the presence of a [4Fe-4S] cluster that serves to reductively homolyze S -adenosyl-L-methionine (SAM) and thereby generate methionine ( 17 ) and a 5′-deoxyadenosyl radical (5′-dAdo•, 18, see Scheme 2) that initiates a radical-mediated transformation of substrate to product. 21–23 The catalytic [4Fe-4S] cluster is typically coordinated by a highly conserved CxxxCxxC motif; 24 however, in the case of AprD4, a non-canonical CxxxCxxxC motif is observed instead.…”

C3′‐Deoxygenation of Paromamine Catalyzed by a Radical S‐Adenosylmethionine Enzyme: Characterization of the Enzyme AprD4 and Its Reductase Partner AprD3

“…[1] Although the biosynthesis of 2-DOS has been investigated in detail, [8][9][10] much less is known regarding assembly of the sugar appendages [11,12] and in particular the mechanism of C3'-deoxygenation despite its importance to the development and improvement of clinically useful aminoglycoside antibiotics. [13] Theg ene clusters responsible for the biosynthesis of apramycin (2), tobramycin (3), and lividomycin B( 5)i n Streptomyces and Streptoalloteichius species have been described, [14][15][16][17] and significant progress has been made in elucidating the reactions involved in the tobramycin pathway. [18,19] Although no gene in the tobramycin cluster has been implicated in catalyzing C3'-deoxygenation, [14,15] investigations,i ncluding gene-knockout studies [20] into the apramycin and lividomycin Bp athways,h ave identified the AprD4/ AprD3 and LivW/LivY enzyme pairs as likely candidates for the activity.F or example,i ncorporation of the aprD4 and aprD3 genes into the kanamycin-producing (see 6)s train S. kanamyceticus led to the isolation of 3'-deoxykanamycins (such as 7), [19] which are not normally produced.…”

“…[13] Theg ene clusters responsible for the biosynthesis of apramycin (2), tobramycin (3), and lividomycin B( 5)i n Streptomyces and Streptoalloteichius species have been described, [14][15][16][17] and significant progress has been made in elucidating the reactions involved in the tobramycin pathway. [18,19] Although no gene in the tobramycin cluster has been implicated in catalyzing C3'-deoxygenation, [14,15] investigations,i ncluding gene-knockout studies [20] into the apramycin and lividomycin Bp athways,h ave identified the AprD4/ AprD3 and LivW/LivY enzyme pairs as likely candidates for the activity.F or example,i ncorporation of the aprD4 and aprD3 genes into the kanamycin-producing (see 6)s train S. kanamyceticus led to the isolation of 3'-deoxykanamycins (such as 7), [19] which are not normally produced. Likewise, previous studies have also shown the conversion of neamine (9)t on ebramine (10)i nc ell-free extracts of S. venezuelae expressing proteins AprD4 and AprD3.…”

Identification and Diversity of Putative Aminoglycoside-Biosynthetic Aminotransferase Genes from Deep-Sea Environmental DNA

“…Genetic and enzymological studies have characterized the biosynthesis of both types of aminoglycosides. [7][8][9][10][11] The gene stsC encodes aminotransferase involved in the biosynthetic pathway of streptomycin. 7) This enzyme catalyzes the transfer of an amino group from Lglutamine to scyllo-inosose, and contributes to the biosynthesis of aglycone in streptomycin.…”