RNA Acylation Method via a DNA-Templated Acyl Transfer Reaction.

We report a RNA acylation strategy, namely, DNA-templated PNA-based RNA acylation, involving a DNA template and a peptide nucleic acid (PNA) strand. The DNA template is designed to hybridize with the accepting RNA and the donating PNA, so that the acyl group on the PNA is transferred to the 3'-end ribose hydroxyl group of the accepting RNA. This PNA system will provide a simple route for RNA acylation.

Employing Broad Substrate Specificity of Omniligase to Generate Phage-Encoded Bicyclic Peptide Libraries for Ligand Discovery.

We report an enzymatic cyclization strategy termed omniligase-mediated peptide bicyclization. An electrophilic group was introduced into the recognition sequence of omniligase to achieve intramolecular bicyclization with Cys residues. In combination with phage display, we identified a bicyclic peptide ligand targeting TEAD4 with a value of 1.

A Ligase-Based Two-Step Approach for the Generation of Bicyclic Peptides Containing a Benzylphenyl Thioether Framework.

This study describes a ligase-based two-step strategy to prepare a unique type of bicyclic peptide molecules containing a benzyl phenyl thioether arm. Different from the conventional bicyclic peptide construction method, this study first utilizes peptide ligases (SrtA or OaAEP1) to introduce an arylthiol group into the parent peptides and then performs bicyclization of the peptides by using TBMB to generate the desired bicyclic peptides. Since the pKa of aryl thiols is lower than that of alkyl thiols, the bicyclization reaction of the peptides in our system can occur under low concentrations of TBMB or low pH conditions.

Thiazolidine Deprotection Using an Organic Solvent Extractable Aldehyde Scavenger for One-Pot Four-Segment Ligation.

We report a simple and convenient N-terminal thiazolidine (Thz) deprotection strategy and its application in one-pot multisegment ligation. In this strategy, -benzylhydroxylamine (O-BHA) is used to efficiently and rapidly convert Thz into N-terminal cysteine. O-BHA can be easily separated from the ligation buffer by organic solvent extraction, avoiding the degradation of the peptide thioester by O-BHA.

Gene cloning and molecular characterization of a thermostable chitosanase from Bacillus cereus TY24.

Background: An important conceptual advance in health and the environment has been recognized that enzymes play a key role in the green processing industries. Of particular interest, chitosanase is beneficial for recycling the chitosan resource and producing chitosan oligosaccharides. Also, chitosan gene expression and molecular characterization will promote understanding of the biological function of bacterial chitosanase as well as explore chitosanase for utilizing chitosan resources.

Identification of plasma SAA2 as a candidate biomarker for the detection and surveillance of non-small cell lung cancer.

This study aimed to measure the expression of SAA2 in plasma and to assess its diagnostic efficacy as a biomarker for non-small cell lung cancer (NSCLC). The gene expression of SAA2 in NSCLC was analyzed based on a database. Then, SAA2 expression was detected by immunohistochemistry in lung tissue and by enzyme-linked immunosorbent assay in 90 patients with NSCLC and 61 normal controls.

[Status of Antibiotic Contamination and Ecological Risks Assessment of Several Typical Chinese Surface-Water Environments].

To learn about the status of antibiotic contamination and their ecological risks in Chinese surface-water environments, the risk quotient (RQ) and joint risk quotient (RQ) methods were applied to assess the ecological risks of five typical surface-water environments in China during the flood season. The results showed that the main types of antibiotic contamination in the five regions were sulfamethoxazole (SMX), sulfamethazine (SM), erythromycin (ETM), roxithromycin (RTM), tetracycline (TC), oxytetracycline (OTC), norfloxacin (NOR), and ofloxacin (OFL). Among eight types of antibiotic contamination, sulfamethoxazole (SMX) and erythromycin (ETM) occupied a dominant position.

Histone acetyltransferase CBP-related H3K23 acetylation contributes to courtship learning in Drosophila.

Background: Histone modifications are critical in regulating neuronal processes. However, the impacts of individual histone modifications on learning and memory are elusive. Here, we investigated the contributions of histone H3 lysine modifications to learning and memory in Drosophila by using histone lysine-to-alanine mutants.

Histone H3K27 methylation modulates the dynamics of FANCD2 on chromatin to facilitate NHEJ and genome stability.

Dysregulation of the homeostatic balance of histone H3 di- and tri-methyl lysine 27 (H3K27me2/3) levels caused by the mis-sense mutation of histone H3 (H3K27M) is reported to be associated with various types of cancers. In this study, we found that reduction in H3K27me2/3 caused by H3.1K27M, a mutation of H3 variants found in patients with diffuse intrinsic pontine glioma (DIPG), dramatically attenuated the presence of 53BP1 (also known as TP53BP1) foci and the capability of non-homologous end joining (NHEJ) in human dermal fibroblasts.

Histone H1-mediated epigenetic regulation controls germline stem cell self-renewal by modulating H4K16 acetylation.

Epigenetics plays critical roles in controlling stem cell self-renewal and differentiation. Histone H1 is one of the most critical chromatin regulators, but its role in adult stem cell regulation remains unclear. Here we report that H1 is intrinsically required in the regulation of germline stem cells (GSCs) in the Drosophila ovary.

Depletion of histone deacetylase 3 antagonizes PI3K-mediated overgrowth of Drosophila organs through the acetylation of histone H4 at lysine 16.

Core histone modifications play an important role in chromatin remodeling and transcriptional regulation. Histone acetylation is one of the best-studied gene modifications and has been shown to be involved in numerous important biological processes. Herein, we demonstrated that the depletion of histone deacetylase 3 (Hdac3) in Drosophila melanogaster resulted in a reduction in body size.

E2 ligase dRad6 regulates DMP53 turnover in Drosophila.

The turnover of tumor suppressor p53 is critical for its role in various cellular events. However, the pathway that regulates the turnover of the Drosophila melanogaster DMP53 is largely unknown. Here, we provide evidence for the first time that the E2 ligase, Drosophila homolog of Rad6 (dRad6/Dhr6), plays an important role in the regulation of DMP53 turnover.