Publications by authors named "Huiwei Zhao"

Article Synopsis
  • Prokaryotic CRISPR-Cas systems face threats from phage-encoded anti-CRISPR (Acr) factors, compromising their defense mechanisms.
  • Researchers discovered a phage-derived toxic protein that acts as a broad-spectrum anti-anti-CRISPR strategy, halting cell division when CRISPR-Cas effectors are inhibited.
  • This mechanism not only helps expel Acr elements from bacterial populations but also enables the identification of specific Acr proteins that enhance CRISPR efficiency against non-target DNA, suggesting CRISPR-Cas systems may provide a form of herd immunity against genetic invaders.
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CRISPR RNAs (crRNAs) and Cas proteins work together to provide prokaryotes with adaptive immunity against genetic invaders like bacteriophages and plasmids. However, the coordination of crRNA production and cas expression remains poorly understood. Here, we demonstrate that widespread modulatory mini-CRISPRs encode cas-regulating RNAs (CreRs) that mediate autorepression of type I-B, I-E, and V-A Cas proteins, based on their limited complementarity to cas promoters.

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CreTA, CRISPR-regulated toxin-antitoxin (TA), safeguards CRISPR-Cas immune systems by inducing cell dormancy/death upon their inactivation. Here, we characterize a bacterial CreTA associating with the I-F CRISPR-Cas in Acinetobacter. CreT is a distinct bactericidal small RNA likely targeting several essential RNA molecules that are required to initiate protein synthesis.

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Intercellular signaling is indispensable for single cells to form complex biological structures, such as biofilms, tissues and organs. The genetic tools available for engineering intercellular signaling, however, are quite limited. Here we exploit the chemical diversity of biological small molecules to de novo design a genetic toolbox for high-performance, multi-channel cell-cell communications and biological computations.

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Butenoic acid is a short-chain unsaturated fatty acid and important precursor for pharmaceutical and other applications. Heterologous thioesterases are able to convert a fatty acid biosynthesis intermediate in Escherichia coli to butenoic acid. In order to acquire high titer and yield of the product, dynamically switching the metabolic flux from fatty acid biosynthesis pathway to butenoic acid is critical after achieving enough cell mass of the host.

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There is growing concern that Cd in soils can be transferred to plants, resulting in phytotoxicity and threats to human health via the food chain. Biochar has been reported to be a soil amendment capable of reducing the bioavailability of metals in soil by electrostatic interactions, ionic exchange and the specific binding of metal ions by surface ligands. To determine the effects of Cd contamination and nanobiochar on the growth characteristics of plants, the dynamics of Cd in soil were explored in Petri dish and pot experiments (0%, 0.

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With a unique crRNA processing capability, the CRISPR associated Cpf1 protein holds great potential for multiplex gene regulation. Unlike the well-studied Cas9 protein, however, conversion of Cpf1 to a transcription regulator and its related properties have not been systematically explored yet. In this study, we investigated the mutation schemes and crRNA requirements for the DNase deactivated Cpf1 (dCpf1).

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Artificial genetic parts should be modularized and can be predictably scaled up via assembly or reused in other contexts. Under intracellular physiological conditions, however, the functions of the assembled parts are severely impeded by multi-level physiological interference, i.e.

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