Carbon-Dots-Mediated Improvement of Antimicrobial Activity of Natural Products.

The development of new microbicidal compounds has become a top priority due to the emergence and spread of drug-resistant pathogenic microbes. In this study, blue-emitting and positively charged carbon dots (CDs), called Du-CDs, were fabricated for the first time utilizing the natural product extract of endophyte YSP3 as raw material through a one-step solvothermal method, which possessed varied functional groups including amino, carboxyl, hydroxyl, and sulfite groups. Interestingly, Du-CDs exhibited notably enhanced antimicrobial activities toward both bacteria and fungi as compared to the natural product extract of YSP3, with low minimum inhibitory concentrations.

See the Unseen: Red-Emissive Carbon Dots for Visualizing the Nucleolar Structures in Two Model Animals and In Vivo Drug Toxicity.

Nucleolus, which participates in many crucial cellular activities, is an ideal target for evaluating the state of a cell or an organism. Here, bright red-emissive carbon dots (termed CPCDs) with excitation-independent/polarity-dependent fluorescence emission are synthesized by a one-step hydrothermal reaction between congo red and p-phenylenediamine. The CPCDs can achieve wash-free, real-time, long-term, and high-quality nucleolus imaging in live cells, as well as in vivo imaging of two common model animals-zebrafish and Caenorhabditis elegans (C.

Chitosan-modified fluorescent dye for simple, fast, and in-situ measurement of fungal cell growth in the presence of insoluble compounds.

The measurement of fungal cell growth in submerged culture systems containing insoluble compounds is essential yet difficult due to the interferences from the insoluble compounds like biopolymers. Here, we developed a fluorescent strategy based on chitosan-modified fluorescein isothiocyanate (GC-FITC) to monitor the cell growth of lignocellulosic fungi cultivated on biopolymers. GC-FITC could stain only lignocellulosic fungi (Tricoderma reesei, Penicillium oxalicum, Aspergillus nidulans, and Neurospora crassa), but not biopolymers (cellulose, xylan, pectin, or lignin), excluding the interferences from these insoluble biopolymer.

Nucleus-targeting pH-Responsive carbon dots for fast nucleus pH detection.

Nucleus pH is closely linked to many diseases such as aging, heart disease, skeletal myopathies, cancer, Alzheimer's disease, etc. Nevertheless, fluorescent sensors that can directly monitor nucleus pH changes have not yet been reported. Here, we first reported a green emissive carbon dots (CDs) for nucleus pH detection in living cells.

Intron retention coupled with nonsense-mediated decay is involved in cellulase biosynthesis in cellulolytic fungi.

Background: Knowledge on regulatory networks associated with cellulase biosynthesis is prerequisite for exploitation of such regulatory systems in enhancing cellulase production with low cost. The biological functions of intron retention (IR) and nonsense-mediated mRNA decay (NMD) in filamentous fungi is lack of study, let alone their roles in cellulase biosynthesis.

Results: We found that major cellulase genes (cel7a, cel7b, and cel3a) exhibited concomitant decrease in IR rates and increase in their gene expression in T.

Transmembrane transport process and endoplasmic reticulum function facilitate the role of gene cel1b in cellulase production of Trichoderma reesei.

Background: A total of 11 β-glucosidases are predicted in the genome of Trichoderma reesei, which are of great importance for regulating cellulase biosynthesis. Nevertheless, the relevant function and regulation mechanism of each β-glucosidase remained unknown.

Results: We evidenced that overexpression of cel1b dramatically decreased cellulase synthesis in T.

Carbon dots for multicolor cell imaging and ultra-sensitive detection of multiple ions in living cells: One Stone for multiple Birds.

Given the significant impact of ions on environment pollution and human health, it is urgently needed to establish effective and convenient ion detection approaches, particularly in living cells. In this paper, we constructed multicolor N-doped-carbon dots (mPD-CDs) by facile one-step hydrothermal carbonization of m-phenylenediamine (mPD). mPD-CDs were successfully deployed for multicolor cellular imaging for animal cells, fungi, and bacteria in a wash-free way with high photostability and satisfactory biocompability.

Plant-derived Ca, N, S-Doped carbon dots for fast universal cell imaging and intracellular Congo red detection.

Congo red (CR) is a hazardous pigment, posing increasing dangerous to the environment and human health. However, the in-situ detection of CR in living cells has not been reported, as far as we know. Here, negatively-charged green-emitting Ca, N, S-doped carbon dots (Mis-mPD-CDs) were fabricated from plant and m-phenylenediamine (mPD) by facile one-step hydrothermal carbonization.

Glutamine involvement in nitrogen regulation of cellulase production in fungi.

Background: Cellulase synthesized by fungi can environment-friendly and sustainably degrades cellulose to fermentable sugars for producing cellulosic biofuels, biobased medicine and fine chemicals. Great efforts have been made to study the regulation mechanism of cellulase biosynthesis in fungi with the focus on the carbon sources, while little attention has been paid to the impact and regulation mechanism of nitrogen sources on cellulase production.

Results: Glutamine displayed the strongest inhibition effect on cellulase biosynthesis in Trichoderma reesei, followed by yeast extract, urea, tryptone, ammonium sulfate and L-glutamate.

CRISPR-Cas13a mediated nanosystem for attomolar detection of canine parvovirus type 2.

Canine parvovirus type 2 (CPV-2) infection is the most lethal disease of dogs with higher mortality in puppies worldwide. In today's world, dogs are an integral part of our communities as well as dogs breeding and rearing has become a lucrative business. Therefore, a fast, accurate, portable, and cost-effective CPV-2 detection method with the ability for on-site detection is highly desired.