An endo-β-1,4-glucanase gene, cel7A, was cloned from the thermophilic cellulase-producing fungus Neosartorya fischeri P1 and expressed in Pichia pastoris. The 1,410-bp full-length gene encodes a polypeptide of 469 amino acids consisting of a putative signal peptide at residues 1–20, a catalytic domain of glycoside hydrolase family 7 (GH7), a short Thr/Ser-rich linker and a family 1 carbohydrate-binding module (CBM 1). The purified recombinant Cel7A had pH and temperature optima of pH 5.0 and 60°C, respectively, and showed broad pH adaptability (pH 3.0–6.0) and excellent stability at pH3.0–8.0 and 60°C. Belonging to the group of nonspecific endoglucanases, Cel7A exhibited the highest activity on barley β-glucan (2020 ± 9 U mg–1), moderate on lichenan and CMC-Na, and weak on laminarin, locust bean galactomannan, Avicel, and filter paper. Under simulated mashing conditions, addition of Cel7A (99 μg) reduced the mash viscosity by 9.1% and filtration time by 24.6%. These favorable enzymatic properties make Cel7A as a good candidate for applications in the brewing industry.

Glycosylation is an efficient strategy to modulate the solubility, stability, bioavailability and bioactivity of drug-like natural products. Biological methods, such as whole-cell biocatalyst, promise a simple but highly effective approach to glycosylate biologically active small molecules with remarkable regio- and stereo-selectivity. Herein, we use the entomopathogenic filamentous fungus Isaria fumosorosea ACCC 37814 to biotransform a panel of phenolic natural products, including flavonoids and anthraquinone, into their glycosides. Six new flavonoid (4-O-methyl)glucopyranosides are obtained and structurally characterized using high resolution mass and nuclear magnetic resonance spectroscopic techniques. These compounds further expand the structural diversity of flavonoid glycosides and may be used in biological study.

A highly N-phosphonomethylglycine (glyphosate)-resistant Pseudomonas fluorescens G2 5-enolpyruvyl shikimate-3-phosphate synthase (EPSPS) was mapped to identify potential split sites using a transposon-based linker-scanning procedure. Intein-mediated protein complementation was used to reconstitute glyphosate resistance from the genetically divided G2 EPSPS gene in Escherichia coli strain ER2799 and transgenic tobacco.

Glyphosate, a powerful nonselective herbicide, acts as an inhibitor of the activity of the enzyme 5-enoylpyruvylshikimate-3-phosphate synthase (EPSPS) encoded by the aroA gene involved in aromatic amino acid biosynthesis. An Escherichia coli mutant AKM4188 was constructed by insertion a kanamycin cassette within the aroA coding sequence. The mutant strain is an aromatic amino acids auxotroph and fails to grow on M9 minimal media due to the inactive aroA. A DNA metagenomic library was constructed with samples from a glyphosate-polluted area and was screened by using the mutant AKM4188 as recipient. Three plasmid clones, which restored growth to the aroA mutant in M9 minimal media supplemented with chloramphenicol, kanamycin, and 50 mM: glyphosate, were obtained from the DNA metagenomic library. One of them, which conferred glyphosate tolerance up to 150 mM: , was further characterized. The cloned fragment encoded a polypeptide, designated RD, sharing high similarity with other Class II EPSPS proteins. A His-tagged RD fusion protein was produced into E. coli to characterize the enzymatic properties of the RD EPSP protein.

Increasing attention has been focused on plant-derived peptides because of their potential bioactivities. In this study, bioactive peptides were released from extruded adzuki bean protein by simulated gastrointestinal digestion. A peptide (KQS-1) sequenced as KQSESHFVDAQPEQQQR was separated and identified using ultrafiltration, pre-high-performance liquid chromatography (HPLC), and ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). KQS-1 was shown to exert significant anti-inflammatory effects in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages by reducing the production of IL-1, IL-6, TNF-α, and MCP-1 to 38.31, 6.07, 43.96, and 41.74%, respectively. The involved signaling pathways were identified by transcriptome analysis. Overall, 5236 differentially expressed genes (DEGs) were identified. Gene ontology (GO) functions demonstrated that DEGs were significantly related to the NF-κB pathway. In conclusion, KQS-1 prevented the activation and expression of NF-κB/caspase-1 by upstream and downstream factors. These findings highlight the bioactivity of adzuki bean peptides.

Herbicides are important tools for weed control in modern agriculture. In the search for potential herbicidal natural products from fungal species, harzianum A and B were identified from the biofertilizer fungus, Trichoderma brevicompactum. In the phytotoxicity assays on the dicot species Brassica chinensis, harzianum A and B reduced both shoot and root lengths at low concentrations and inhibited the seed germination at 2 μg mL −1. In addition, harzianum A and B also exhibited phytotoxicity against monocots, Oryza sativa L. cv. Nipponbare and Echinochloa crusgalli L. Beauv.. Compared with a common herbicide, 2,4-dichlorophenoxyacetic acid, harzianum A and B performed similar activity in a pot assay, and were more effective in post-emergence than pre-emergence conditions. Harzianum A and B have potential as efficient herbicide for controlling important dicotyledon and monocotyledon weeds at low concentrations. They can be sprayed in liquid form in both pre-and post-emergence conditions. Our results confirmed the importance of these molecules for the development of new herbicides.

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