Expression of double-stranded-RNA-specific RNase III of Escherichia coli is lethal to Saccharomyces cerevisiae.

RNA interference (RNAi) is a valuable and revolutionary technology that has been widely applied in medicine and agriculture. The application of RNAi in various industries requires large amounts of low-cost double-stranded RNA (dsRNA). Chemical synthesis can only produce short dsRNAs; long dsRNAs need to be synthesized biologically. Several microbial chassis cells, such as Escherichia coli, Saccharomyces cerevisiae, and Bacillus species, have been used for dsRNA synthesis. However, the titer, rate of production, and yield of dsRNA obtained by these microorganism-based strategies is still low. In this review, we summarize advances in microbial dsRNA production, and analyze the merits and faults of different microbial dsRNA production systems. This review provides a guide for dsRNA production system selection. Future development of efficient microbial dsRNA production systems is also discussed.

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Heterodimer-based analysis of subunit and domain contributions to double-stranded RNA processing by Escherichia coli RNase III in vitro

Biochemical Journal ◽

10.1042/bj20071047 ◽

2008 ◽

Vol 410 (1) ◽

pp. 39-48 ◽

Cited By ~ 21

Author(s):

Wenzhao Meng ◽

Allen W. Nicholson

Keyword(s):

Escherichia Coli ◽

Rna Processing ◽

Metal Ion ◽

Catalytic Site ◽

Ion Concentration ◽

Hill Coefficient ◽

Rnase Iii ◽

Double Stranded Rna ◽

Catalytic Sites ◽

Scissile Bond

Members of the RNase III family are the primary cellular agents of dsRNA (double-stranded RNA) processing. Bacterial RNases III function as homodimers and contain two dsRBDs (dsRNA-binding domains) and two catalytic sites. The potential for functional cross-talk between the catalytic sites and the requirement for both dsRBDs for processing activity are not known. It is shown that an Escherichia coli RNase III heterodimer that contains a single functional wt (wild-type) catalytic site and an inactive catalytic site (RNase III[E117A/wt]) cleaves a substrate with a single scissile bond with a kcat value that is one-half that of wt RNase III, but exhibits an unaltered Km. Moreover, RNase III[E117A/wt] cleavage of a substrate containing two scissile bonds generates singly cleaved intermediates that are only slowly cleaved at the remaining phosphodiester linkage, and in a manner that is sensitive to excess unlabelled substrate. These results demonstrate the equal probability, during a single binding event, of placement of a scissile bond in a functional or nonfunctional catalytic site of the heterodimer and reveal a requirement for substrate dissociation and rebinding for cleavage of both phosphodiester linkages by the mutant heterodimer. The rate of phosphodiester hydrolysis by RNase III[E117A/wt] has the same dependence on Mg2+ ion concentration as that of the wt enzyme, and exhibits a Hill coefficient (h) of 2.0±0.1, indicating that the metal ion dependence essentially reflects a single catalytic site that employs a two-Mg2+-ion mechanism. Whereas an E. coli RNase III mutant that lacks both dsRBDs is inactive, a heterodimer that contains a single dsRBD exhibits significant catalytic activity. These findings support a reaction pathway involving the largely independent action of the dsRBDs and the catalytic sites in substrate recognition and cleavage respectively.

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Microbe Engineering of Guaia-6,10(14)-diene as a Building Block for the Semisynthetic Production of Plant-Derived (−)-Englerin A

10.26434/chemrxiv.10333625.v1 ◽

2019 ◽

Author(s):

Thomas Siemon ◽

Zhangqian Wang ◽

Guangkai Bian ◽

Tobias Seitz ◽

Ziling Ye ◽

...

Keyword(s):

Escherichia Coli ◽

Saccharomyces Cerevisiae ◽

Synthetic Biology ◽

Chemical Synthesis ◽

Building Block ◽

Transient Receptor Potential ◽

Receptor Potential ◽

Economical Method ◽

Englerin A ◽

Transient Receptor

Herein, we report the semisynthetic production of the potent transient receptor potential canonical (TRPC) channel agonist (−)-englerin A (EA), using guaia-6,10(14)-diene as the starting material. Guaia-6,10(14)-diene was systematically engineered in Escherichia coli and Saccharomyces cerevisiae using the CRISPR/Cas9 system and produced with high titers. This provided us the opportunity to execute a concise chemical synthesis of EA and the two related guaianes (−)-oxyphyllol and (+)-orientalol E. The potentially scalable approach combines the advantages of synthetic biology and chemical synthesis and provides an efficient and economical method for producing EA as well as its analogs.

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Microbe Engineering of Guaia-6,10(14)-diene as a Building Block for the Semisynthetic Production of Plant-Derived (−)-Englerin A

10.26434/chemrxiv.10333625 ◽

2019 ◽

Author(s):

Thomas Siemon ◽

Zhangqian Wang ◽

Guangkai Bian ◽

Tobias Seitz ◽

Ziling Ye ◽

...

Keyword(s):

Escherichia Coli ◽

Saccharomyces Cerevisiae ◽

Synthetic Biology ◽

Chemical Synthesis ◽

Building Block ◽

Transient Receptor Potential ◽

Receptor Potential ◽

Economical Method ◽

Englerin A ◽

Transient Receptor

Herein, we report the semisynthetic production of the potent transient receptor potential canonical (TRPC) channel agonist (−)-englerin A (EA), using guaia-6,10(14)-diene as the starting material. Guaia-6,10(14)-diene was systematically engineered in Escherichia coli and Saccharomyces cerevisiae using the CRISPR/Cas9 system and produced with high titers. This provided us the opportunity to execute a concise chemical synthesis of EA and the two related guaianes (−)-oxyphyllol and (+)-orientalol E. The potentially scalable approach combines the advantages of synthetic biology and chemical synthesis and provides an efficient and economical method for producing EA as well as its analogs.

Download Full-text