Publications by authors named "Ce Geng"

Trans-aconitic acid (TAA) is a promising bio-based chemical with the structure of unsaturated tricarboxylic acid, and also has the potential to be a non-toxic nematicide as a potent inhibitor of aconitase. However, TAA has not been commercialized because the traditional production processes of plant extraction and chemical synthesis cannot achieve large-scale production at a low cost. The availability of TAA is a serious obstacle to its widespread application.

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Flavonoids are important plant natural products with variable structures and bioactivities. All known plant flavonoids are generated under the catalysis of a type III polyketide synthase (PKS) followed by a chalcone isomerase (CHI) and a flavone synthase (FNS). In this study, the biosynthetic gene cluster of chlorflavonin, a fungal flavonoid with acetolactate synthase inhibitory activity, was discovered using a self-resistance-gene-directed strategy.

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Micafungin, a semisynthetic derivative of the cyclic hexapeptide FR901379 produced by Coleophoma empetri fermentation, is the only O-sulfonated echinocandin-type antifungal drug. However, the detailed formation mechanism of O-sulfonate group, whether before or after the assembly of hexapeptide, remains elusive. Here, we confirmed that O-sulfonylation occurs after hexapeptide assembly as a kind of postmodification in the biosynthesis of FR901379.

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Physcion is a characteristic component of the traditional herb rhubarb with diverse pharmacological activities that has been commercially approved as an herbal fungicide. Nevertheless, its extremely low contents, costly purification procedure and geographically restricted planting severely hinder its application. Here, a cell factory was constructed in the filamentous fungus Aspergillus terreus for physcion production via microbial fermentation by integrating a pathway-modified emodin accumulation module and a position-selective emodin methylation module.

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All -methylated derivatives of emodin, including physcion, questin, and 1--methylemodin, show potential antifungal activities. Notably, emodin and questin are two pivotal intermediates of geodin biosynthesis in . Although most of the geodin biosynthetic steps have been investigated, the key -methyltransferase (OMT) responsible for the -methylation of emodin to generate questin has remained unidentified.

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The C-10-C-4a bond cleavage of anthraquinone is believed to be a crucial step in fungal seco-anthraquinone biosynthesis and has long been proposed as a classic Baeyer-Villiger oxidation. Nonetheless, genetic, enzymatic, and chemical information on ring opening remains elusive. Here, a revised questin ring-opening mechanism was elucidated by gene disruption, enzymatic analysis, and O chasing experiments.

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The knowledge on sulfur incorporation mechanism involved in sulfur-containing molecule biosynthesis remains limited. Chuangxinmycin is a sulfur-containing antibiotic with a unique thiopyrano[4,3,2-cd]indole (TPI) skeleton and selective inhibitory activity against bacterial tryptophanyl-tRNA synthetase. Despite the previously reported biosynthetic gene clusters and the recent functional characterization of a P450 enzyme responsible for C-S bond formation, the enzymatic mechanism for sulfur incorporation remains unknown.

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Micafungin is an important echinocandin antifungal agent for the treatment of invasive fungal infections. In industry, micafungin is derived from the natural product FR901379, which is a non-ribosomal cyclic hexapeptide produced by the filamentous fungus . The difficulty of genetic manipulation in restricts the clarification of FR901379 biosynthetic mechanism.

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Fungal polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) hybrids have been characterized to produce polyketide-amino acid compounds with striking structural features and biological activities. In this study, a PKS-NRPS hybrid enzyme was found in by genome mining. By activating the cluster-specific transcriptional regulator, this cryptic PKS-NRPS gene cluster was successfully activated and ten products (-) were identified as pyranterreones.

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Identification and analysis of the whole genome of the marine-derived fungus HBU-136 revealed the presence of an interesting biosynthetic gene cluster (BGC) for non-ribosomal peptide synthetases (NRPS), highly homologous to the BGCs of indole-diketopiperazine derivatives. With the aid of genomic analysis, eight indole-diketopiperazines (-), including three new compounds, spirotryprostatin G (), and cyclotryprostatins F and G ( and ), were obtained by large-scale cultivation of the fungal strain HBU-136 using rice medium with 1.0% MgCl.

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Mycophenolic acid (MPA) from filamentous fungi is the first natural product antibiotic to be isolated and crystallized, and a first-line immunosuppressive drug for organ transplantations and autoimmune diseases. However, some key biosynthetic mechanisms of such an old and important molecule have remained unclear. Here, we elucidate the MPA biosynthetic pathway that features both compartmentalized enzymatic steps and unique cooperation between biosynthetic and β-oxidation catabolism machineries based on targeted gene inactivation, feeding experiments in heterologous expression hosts, enzyme functional characterization and kinetic analysis, and microscopic observation of protein subcellular localization.

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Despite the successful application of crystal proteins (Cry) from as biological control agents against insects, there is an increasing demand to identify new Cry toxins having higher toxicity and broad-spectrum activity against insects and plant-parasitic nematodes. To find novel Cry toxins, we screened 100 whole-genome sequences of Surprisingly, in addition to full Cry toxins, we found partial sequences, such as typical N-terminal or C-terminal regions with conserved domains, widely distributed among 20 strains of In order to further elucidate the functions of partial genes, here, we selected a partial sequence from strain C15, having 28% similarity with the N terminus of Cry5Ba and lacking a typical C terminus, and denoted it Cry5B-like N terminus. This fragment when coexpressed as a fusion protein with the C terminus of Cry5Ba (N-C fusion protein) produces pyramidal crystals.

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Cry proteins of (Bt) have been successfully used as biopesticides and in transgenic crops throughout the world. However, resources against the most serious agricultural pathogens, plant root-knot nematodes, are limited. The genomes of several highly nematicidal virulent Bt strains from our laboratory have been sequenced, facilitating the identification of novel Cry proteins and other virulence factors.

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The data presented in this article are related to the published entitled "Whole-genome sequencing of LS69, a strain with a broad inhibitory spectrum against pathogenic bacteria" (Liu et al., 2017) [1]. Genome analysis revealed LS69 has a good potential for biocontrol and plant growth promotion.

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Bacillus velezensis LS69 was found to exhibit antagonistic activity against a diverse spectrum of pathogenic bacteria. It has one circular chromosome of 3,917,761bp with 3,643 open reading frames. Genome analysis identified ten gene clusters involved in nonribosomal synthesis of polyketides (macrolactin, bacillaene and difficidin), lipopeptides (surfactin, fengycin, bacilysin and iturin A) and bacteriocins (amylolysin and amylocyclicin).

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Plant-parasitic nematodes (PPNs) cause serious harm to agricultural production. Bacillus firmus shows excellent control of PPNs and has been produced as a commercial nematicide. However, its nematicidal factors and mechanisms are still unknown.

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Bacillus thuringiensis CTC, which is identified as serotype H2, serovar. finitimus, is high production of S-layer protein. Due to the property of forming isoporous lattices on the whole cell surface, S-layer protein has been widely used in (nano) biotechnology, biomimetics, biomedicine, especially been employed for displaying many important active proteins.

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Root-knot nematodes (RKNs) can infect almost all crops, and result in huge economic losses in agriculture. There is no effective and environmentally safe means available to control RKNs. Alcaligenes faecalis ZD02 isolated from free living nematode Caenorhabditis elegans cadavers shows toxicity against RKN Meloidogyne incognita, that makes this strain to be a good bionematicide candidate for controlling of RKNs.

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Bacillus thuringiensis has been globally used as a microbial pesticide for over 70 years. However, information regarding its various adaptions and virulence factors and their roles in the entomopathogenic process remains limited. In this work, we present the complete genomes of two industrially patented Bacillus thuringiensis strains (HD-1 and YBT-1520).

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The entomopathogen Bacillus thuringiensis is equipped with multiple virulent factors. The genome sequence of B. thuringiensis YBT1520 revealed the presence of a two-domain protein named Nel which is composed of a necrosis-inducing phytophthora protein 1-like domain found in phytopathogens and a ricin B-like lectin domain.

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Bacillus firmus DS1, an aerobic, Gram-positive, spore-forming bacterium isolated from marine sediment of the China South Sea coast. Here, the first draft genome sequence of B. firmus DS1 that may help us to clarify the evolutionary status of B.

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