Faculty Opinions recommendation of Nontargeted in vitro metabolomics for high-throughput identification of novel enzymes in Escherichia coli.

Although it is known that the amino acid sequence of a nascent polypeptide can impact its rate of translation, dedicated tools to systematically investigate this process are lacking. Here, we present high-throughput inverse toeprinting, a method to identify peptide-encoding transcripts that induce ribosomal stalling in vitro. Unlike ribosome profiling, inverse toeprinting protects the entire coding region upstream of a stalled ribosome, making it possible to work with random or focused transcript libraries that efficiently sample the sequence space. We used inverse toeprinting to characterize the stalling landscapes of free and drug-boundEscherichia coliribosomes, obtaining a comprehensive list of arrest motifs that were validated in vivo, along with a quantitative measure of their pause strength. Thanks to the modest sequencing depth and small amounts of material required, inverse toeprinting provides a highly scalable and versatile tool to study sequence-dependent translational processes.

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Molecules incorporating a benzothiazole core scaffold inhibit the N-myristoyltransferase of Plasmodium falciparum

Biochemical Journal ◽

10.1042/bj20070692 ◽

2007 ◽

Vol 408 (2) ◽

pp. 173-180 ◽

Cited By ~ 45

Author(s):

Paul W. Bowyer ◽

Ruwani S. Gunaratne ◽

Munira Grainger ◽

Chrislaine Withers-Martinez ◽

Sasala R. Wickramsinghe ◽

...

Keyword(s):

Escherichia Coli ◽

Plasmodium Falciparum ◽

High Throughput ◽

High Throughput Screening ◽

Small Scale ◽

Expression And Purification ◽

Purification System ◽

Pure Protein ◽

Ic50 Values

Recombinant N-myristoyltransferase of Plasmodium falciparum (termed PfNMT) has been used in the development of a SPA (scintillation proximity assay) suitable for automation and high-throughput screening of inhibitors against this enzyme. The ability to use the SPA has been facilitated by development of an expression and purification system which yields considerably improved quantities of soluble active recombinant PfNMT compared with previous studies. Specifically, yields of pure protein have been increased from 12 μg·l−1 to >400 μg·l−1 by use of a synthetic gene with codon usage optimized for expression in an Escherichia coli host. Preliminary small-scale ‘piggyback’ inhibitor studies using the SPA have identified a family of related molecules containing a core benzothiazole scaffold with IC50 values <50 μM, which demonstrate selectivity over human NMT1. Two of these compounds, when tested against cultured parasites in vitro, reduced parasitaemia by >80% at a concentration of 10 μM.

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Inhibitors of RecA Activity Discovered by High-Throughput Screening: Cell-Permeable Small Molecules Attenuate the SOS Response in Escherichia coli

CrossRef Listing of Deleted DOIs ◽

10.1177/1087057109342126 ◽

2009 ◽

Vol 14 (9) ◽

pp. 1092-1101 ◽

Cited By ~ 40

Author(s):

Tim J. Wigle ◽

Jonathan Z. Sexton ◽

Anna V. Gromova ◽

Mallinath B. Hadimani ◽

Mark A. Hughes ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Small Molecules ◽

High Throughput ◽

High Throughput Screening ◽

Bacterial Infections ◽

Sos Response ◽

Cellular Targets ◽

Novel Target

The phenomenon of antibiotic resistance has created a need for the development of novel antibiotic classes with nonclassical cellular targets. Unfortunately, target-based drug discovery against proteins considered essential for in vitro bacterial viability has yielded few new therapeutic classes of antibiotics. Targeting the large proportion of genes considered nonessential that have yet to be explored by high-throughput screening, for example, RecA, can complement these efforts. Recent evidence suggests that RecA-controlled processes are responsible for tolerance to antibiotic chemotherapy and are involved in pathways that ultimately lead to full-fledged antibiotic resistance. Therefore inhibitors of RecA may serve as therapeutic adjuvants in combination chemotherapy of bacterial infectious diseases. Toward the goal of validating RecA as a novel target in the chemotherapy of bacterial infections, the authors have screened 35,780 small molecules against RecA. In total, 80 small molecules were identified as primary hits and could be clustered in 6 distinct chemotype clades. The most potent class of hits was further examined, and 1 member compound was found to inhibit RecA-mediated strand exchange and prevent ciprofloxacin-induced SOS expression in Escherichia coli. This compound represents the first small molecule demonstrating an ability to inhibit the bacterial SOS response in live bacterial cell cultures. ( Journal of Biomolecular Screening 2009:1092-1101)

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