Production of Antitubercular Depsipeptides via Biosynthetic Engineering of Cinnamoyl Units

ABSTRACTCyclophilin inhibitors currently in clinical trials for hepatitis C virus (HCV) are all analogues of cyclosporine (CsA). Sanglifehrins are a group of naturally occurring cyclophilin binding polyketides that are structurally distinct from the cyclosporines and are produced by a microorganism amenable to biosynthetic engineering for lead optimization and large-scale production by fermentation. Preclinical characterization of the potential utility of this class of compounds for the treatment of HCV revealed that the natural sanglifehrins A to D are all more potent than CsA at disrupting formation of the NS5A-CypA, -CypB, and -CypD complexes and at inhibition of CypA, CypB, and CypD isomerase activity. In particular, sanglifehrin B (SfB) was 30- to 50-fold more potent at inhibiting the isomerase activity of all Cyps tested than CsA and was also shown to be a more potent inhibitor of the 1b subgenomic replicon (50% effective concentrations [EC50s] of 0.070 μM and 0.16 μM in Huh 5-2 and Huh 9-13 cells, respectively). Physicochemical and mouse pharmacokinetic analyses revealed low oral bioavailability (F< 4%) and low solubility (<25 μM), although the half-lives (t1/2) of SfA and SfB in mouse blood after intravenous (i.v.) dosing were long (t1/2> 5 h). These data demonstrate that naturally occurring sanglifehrins are suitable lead compounds for the development of novel analogues that are less immunosuppressive and that have improved metabolism and pharmacokinetic properties.

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Biosynthesis of sulfonamide and sulfamate antibiotics in Actinomycete

Journal of Industrial Microbiology & Biotechnology ◽

10.1093/jimb/kuab001 ◽

2021 ◽

Author(s):

Takayoshi Awakawa ◽

Lena Barra ◽

Ikuro Abe

Keyword(s):

Natural Products ◽

Second Generation ◽

Structural Motif ◽

Organosulfur Compounds ◽

Antibacterial Drugs ◽

Structural Motifs ◽

Detailed Understanding ◽

Bacterial Genus ◽

Current State ◽

Biosynthetic Engineering

Abstract Sulfonamides and sulfamates are a group of organosulfur compounds that contain the signature sulfamoyl structural motif. These compounds were initially only known as synthetic antibacterial drugs but were later also discovered as natural products. Eight highly potent examples have been isolated from actinomycetes to date, illustrating the large biosynthetic repertoire of this bacterial genus. For the biosynthesis of these compounds, several distinct and unique biosynthetic machineries have been discovered, capable to generate the unique S-N bond. For the creation of novel, second generation natural products by biosynthetic engineering efforts, a detailed understanding of the underlying enzyme machinery towards potent structural motifs is crucial. In this review, we aim to summarize the current state of knowledge on sulfonamide and sulfamate biosynthesis. A detailed discussion for the secondary sulfamate ascamycin, the tertiary sulfonamide sulfadixiamycin A, and the secondary sulfonamide SB-203208 is provided and their bioactivities and mode of actions are discussed.

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Biosynthetic engineering of the antifungal, anti-MRSA auroramycin

10.1101/829812 ◽

2019 ◽

Author(s):

Wan Lin Yeo ◽

Elena Heng ◽

Lee Ling Tan ◽

Yi Wee Lim ◽

Kuan Chieh Ching ◽

...

Keyword(s):

Antifungal Activity ◽

Genome Editing ◽

Gene Cluster ◽

Biosynthetic Pathway ◽

Biosynthetic Gene Cluster ◽

Combinatorial Biosynthesis ◽

Biosynthetic Gene ◽

Antifungal Activities ◽

Biosynthetic Engineering

AbstractUsing an established CRISPR-Cas mediated genome editing technique for streptomycetes, we explored the combinatorial biosynthesis potential of the auroramycin biosynthetic gene cluster in Streptomyces roseoporous. Auroramycin is a potent anti-MRSA polyene macrolactam. In addition, it also displays antifungal activities, which is unique among structurally similar polyene macrolactams, such as incednine and silvalactam. In this work, we employed different engineering strategies to target glycosylation and acylation biosynthetic machineries within its recently elucidated biosynthetic pathway. Six auroramycin analogs with variations in C-, N-methylation, hydroxylation and extender units incorporation were produced and characterized. By comparing the bioactivity profiles of these analogs, we determined that unique disaccharide motif of auroramycin is essential for its antimicrobial bioactivity. We further demonstrated that C-methylation of the 3, 5-epi-lemonose unit, which is unique among structurally similar polyene macrolactams, is key to its antifungal activity.

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