Decomposition of metabolic network into functional modules based on the global connectivity structure of reaction graph.

Motivation: Metabolic networks are organized in a modular, hierarchical manner. Methods for a rational decomposition of the metabolic network into relatively independent functional subsets are essential to better understand the modularity and organization principle of a large-scale, genome-wide network. Network decomposition is also necessary for functional analysis of metabolism by pathway analysis methods that are often hampered by the problem of combinatorial explosion due to the complexity of metabolic network.

Inclusion complexation and solubilization of paclitaxel by bridged bis(beta-cyclodextrin)s containing a tetraethylenepentaamino spacer.

A novel water-soluble paclitaxel complex has been prepared by inclusion complexation with bridged bis(beta-cyclodextrin)s and characterized by means of (1)H NMR, SEM, powder X-ray diffraction patterns, TG-DTA, DSC, FT-IR, and 2D NOESY. The cyclodextrins were able to solubilize paclitaxel to levels as high as 2 mg/mL. Furthermore, the cytotoxicity of the novel complexes was assessed using a K562 leukemia cell line which indicated that drug concentrations of 10 pg/mL elicited an inhibitory effect.

Biological responses of suspension cultures of Taxus chinensis var. mairei to shear stresses in the short term.

The biological responses of Taxus chinensis var. mairei suspension cultures to a range of shear rates were investigated in a Couette-type shear reactor. It was found that the shear rate below 458 s-1 enhanced the primary metabolism, increasing mitochondrial activity and protein expression and inhibiting the activity of phenylalanine ammonia lyase (PAL), an enzyme relevant to the secondary metabolism.

A structured kinetic model for suspension cultures of Taxus chinensis var. mairei induced by an oligosaccharide from Fusarium oxysporum.

A structured kinetic model was established to describe the process of Taxol formation in suspension cultures of Taxus chinesis var. mairei induced by an oligosaccharide from Fusarium oxysporum. In this model, the role of intracellular starch as a storage carbon source had to be taken into account.

Apoptotic cell death in suspension cultures of Taxus cuspidata co-treated with salicylic acid and hydrogen peroxide.

Apoptotic cell death in suspension cultures of Taxus cuspidata induced by exogenous salicylic acid and/or H2O2 was investigated. H2O2 (0.012% v/v) alone changed the permeability of cell membrane while salicylic acid (0.

Inhibitor studies of isopentenyl pyrophosphate biosynthesis in suspension cultures of the yew Taxus chinensis var. mairei.

Some metabolic inhibitors, mevastatin (MVS), chlorocholine chloride (CCC), sodium pyrophosphate (NaPP) and D,L-glyceraldehyde (DLG), were respectively added into the suspension cultures of the yew Taxus chinensis var. mairei at the late phase of cell growth to study isopentenyl pyrophosphate (IPP) biosynthesis. The content of total taxanes decreased in the cases of MVS, NaPP and DLG addition, regardless of the inhibitor concentration, whereas it increased in the case of CCC addition.

Synthesis and evaluation of water-soluble paclitaxel prodrugs.

A series of water-soluble 2'-paclitaxel prodrugs were synthesized by attaching paclitaxel to polyethylene glycol (PEG) through amino acid spacers. The prodrugs showed highly improved water solubility, enhanced in vitro cytotoxicity and in vivo antitumor activity compared with the native drug, paclitaxel.

[Induced-effects by additional taxol in suspension cultures of Taxus cuspidata cells].

Apoptosis was induced by taxol treatment in suspension cultures of Taxus cuspidata cells. Differential display technique was used to investigate the induced-gene expression between the taxol-induced T. cuspidata cells and normal control.

Isolation of differential genes in suspension cultures of Taxus cuspidata induced by additional taxol.

Addition of taxol into suspension cultures of Taxus cuspidata induced cell apoptosis, which was confirmed by gel electrophoresis of the DNA ladders indicating the progressive delineation of fragmented nuclear DNA (nDNA) into distinct bodies. The additional taxol not only changed the microtubule assembly of cells, but also affected the gene expression. Fourteen cDNA fragments, named as TIGT9-22, were isolated after addition of taxol and their GenBank accession numbers were given as BF704560-BF704573, respectively.