Cheng-Bin Cui

Bio: Cheng-Bin Cui is an academic researcher from Ocean University of China. The author has contributed to research in topics: Aspergillus fumigatus & Cell cycle. The author has an hindex of 15, co-authored 27 publications receiving 1501 citations. Previous affiliations of Cheng-Bin Cui include Chinese Ministry of Education.

Tryprostatin A, a specific and novel inhibitor of microtubule assembly.

Abstract: We have investigated the cell cycle inhibition mechanism and primary target of tryprostatin A (TPS-A) purified from Aspergillus fumigatus. TPS-A inhibited cell cycle progression of asynchronously cultured 3Y1 cells in the M phase in a dose- and time-dependent manner. In contrast, TPS-B (the demethoxy analogue of TPS-A) showed cell-cycle non-specific inhibition on cell growth even though it inhibited cell growth at lower concentrations than TPS-A. TPS-A treatment induced the reversible disruption of the cytoplasmic microtubules of 3Y1 cells as observed by indirect immunofluorescence microscopy in the range of concentrations that specifically inhibited M-phase progression. TPS-A inhibited the assembly in vitro of microtubules purified from bovine brains (40% inhibition at 250 microM); however, there was little or no effect on the self-assembly of purified tubulin when polymerization was induced by glutamate even at 250 microM TPS-A. TPS-A did not inhibit assembly promoted by taxol or by digestion of the C-terminal domain of tubulin. However, TPS-A blocked the tubulin assembly induced by inducers interacting with the C-terminal domain, microtubule-associated protein 2 (MAP2), tau and poly-(l-lysine). These results indicate that TPS-A is a novel inhibitor of MAP-dependent microtubule assembly and, through the disruption of the microtubule spindle, specifically inhibits cell cycle progression at the M phase.

Novel Mammalian Cell Cycle Inhibitors, Tryprostatins A, B and Other Diketopiperazines Produced by Aspergillus fumigatus I. Taxonomy, Fermentation, Isolation and Biological Properties

Abstract: Two novel diketopiperazines named tryprostatins A (1) and B (2) and a new natural product belonging to the diketopiperazine series, designated as demethoxyfumitremorgin C (3), together with four known diketopiperazines, fumitremorgin C (4), 12,13-dihydroxyfumitremorgin C (5), fumitremorgin B (6) and verruculogen (7), were isolated from the fermentation broth of Aspergillus fumigatus BM939 by the combined use of solvent extraction, silica gel column chromatography, preparative TLC and repeated-preparative HPLC. The diketopiperazines showed an inhibitory activity on the cell cycle progression of mouse tsFT210 cells in the M phase with the MIC values of 16.4 microM (1), 4.4 microM (2), 0.45 microM (3), 4.1 microM (4), 60.8 microM (5), 26.1 microM (6) and 12.2 microM (7), respectively.

Novel mammalian cell cycle inhibitors, tryprostatins A, B and other diketopiperazines produced by Aspergillus fumigatus. II. Physico-chemical properties and structures.

Abstract: Two novel diketopiperazines named tryprostatins A and B and a new natural product belonging to the diketopiperazine series, designated as demethoxyfumitremorgin C, together with four known diketopiperazines, fumitremorgin C, 12,13-dihydroxyfumitremorgin C, fumitremorgin B and verruculogen, are new M phase inhibitors of the mammalian cell cycle, which were isolated from the secondary metabolites of Aspergillus fumigatus. The structures of tryprostatins A, B and demethoxyfumitremorgin C were determined mainly by the use of spectroscopic methods especially by detailed analyses of their 1 H and 13 C NMR spectra with the aid of 2D NMR techniques including pulse field gradient heteronuclear multiple-bond correlation (PFG-HMBC) spectroscopy. Their absolute configurations were determined on the basis of the optical rotational values and CD spectra.

Aspergillus fumigatus and Aspergillosis

Abstract: Aspergillus fumigatus is one of the most ubiquitous of the airborne saprophytic fungi. Humans and animals constantly inhale numerous conidia of this fungus. The conidia are normally eliminated in the immunocompetent host by innate immune mechanisms, and aspergilloma and allergic bronchopulmonary aspergillosis, uncommon clinical syndromes, are the only infections observed in such hosts. Thus, A. fumigatus was considered for years to be a weak pathogen. With increases in the number of immunosuppressed patients, however, there has been a dramatic increase in severe and usually fatal invasive aspergillosis, now the most common mold infection worldwide. In this review, the focus is on the biology of A. fumigatus and the diseases it causes. Included are discussions of (i) genomic and molecular characterization of the organism, (ii) clinical and laboratory methods available for the diagnosis of aspergillosis in immunocompetent and immunocompromised hosts, (iii) identification of host and fungal factors that play a role in the establishment of the fungus in vivo, and (iv) problems associated with antifungal therapy.

Aspergillus fumigatus and aspergillosis.

Abstract: SUMMARY Aspergillus fumigatus is one of the most ubiquitous of the airborne saprophytic fungi. Humans and animals constantly inhale numerous conidia of this fungus. The conidia are normally eliminated in the immunocompetent host by innate immune mechanisms, and aspergilloma and allergic bronchopulmonary aspergillosis, uncommon clinical syndromes, are the only infections observed in such hosts. Thus, A. fumigatus was considered for years to be a weak pathogen. With increases in the number of immunosuppressed patients, however, there has been a dramatic increase in severe and usually fatal invasive aspergillosis, now the most common mold infection worldwide. In this review, the focus is on the biology of A. fumigatus and the diseases it causes. Included are discussions of (i) genomic and molecular characterization of the organism, (ii) clinical and laboratory methods available for the diagnosis of aspergillosis in immunocompetent and immunocompromised hosts, (iii) identification of host and fungal factors that play a role in the establishment of the fungus in vivo, and (iv) problems associated with antifungal therapy.

Pyrrolidinyl-spirooxindole natural products as inspirations for the development of potential therapeutic agents.

Abstract: The 3,3'-pyrrolidinyl-spirooxindole unit is a privileged heterocyclic motif that forms the core of a large family of alkaloid natural products with strong bioactivity profiles and interesting structural properties. Significant recent advances in the synthesis of this fused heterocyclic system have led to intense interest in the development of related compounds as potential medicinal agents or biological probes.

Natural product synthesis using multicomponent reaction strategies.

Abstract: The preparation of urea by Wöhler constituted a landmark achievement in organic chemistry, and it laid the ground for the early days of target-oriented organic synthesis.1 Since then, significant progress has been achieved in this discipline; many powerful single bond forming reactions and asymmetric variants have been developed. These discoveries have paved the way for the stereoselective assembly of complex organic molecules, a task deemed inconceivable by early practitioners. A great many strategies were invented by chemists in order to facilitate the synthesis of complex natural products.2 One avenue in emulating nature’s efficiency would * To whom correspondence should be addressed. E-mail: dennis.hall@ ualberta.ca. † Novartis Institute for Biomedical Research. ‡ Department of Chemistry, University of Alberta. Chem. Rev. 2009, 109, 4439–4486 4439