Advances and prospects of taxol biosynthesis by endophytic fungi / 生物工程学报

Taxol is one of the most important chemotherapeutic drugs against cancer. Taxol has been mainly extracted from the bark of yews for a long time. However, methods for the extraction of taxol from the bark of Taxus species were inefficient and environmentally costly. As a result of the high ecological toll exacted on trees with the potential for Pacific yew extinction, investigators began to look for other methods of taxol production. Recently, increasing efforts have been made to develop alternative means of taxol production, such as using complete chemical synthesis, semi-synthesis, Taxus spp. plant cell culture and microbe fermentation. Using microbe fermentation in the production of taxol would be a very prospective method for obtaining a large amount of taxol. Therefore, it is necessary to understand the molecular basis and genetic regulation mechanisms of taxol biosynthesis by endophytic fungi, which may be helpful to construct the genetic engineering strain with high taxol output. In this paper, the taxol biosynthesis pathway from Taxus cells and the advantages of taxol biosynthesis by endophytic fungi were discussed. The study on the isolation and biodiversity of taxol-producing endophytic fungi and the taxol biosynthesis related genes are also discussed.

Analysis of Viable But Non-culturable State of Staphylococcus aureus / 环境与健康杂志

Objective To study the induction and detection methods of Staphylococcus aureus viable but non-culturable state (VBNC).Methods Staphylococcus aureus (ATCC13565) of 107 cfu/ml was induced by low temperature at 4 ℃,freezing at-20 ℃ and adding copper ions from 0.01 mmol/L to 0.05 mmol/L,Staphylococcus aureus was tested,and explored the resuscitation conditions by stepwise heating-heating and chemokinesis.Results Frozen 72 h at the temperature of-20 ℃ or added 0.015 mmol/L Cu2+ for 4 days of culture could induce staphylococcus aureus into the state of VBNC.Adding 0.5% tween-20 or 1% catalase for 24 h of culture could make the strain in VBNC achieve recovery.Conclusion Staphylococcus aureus can be induced into the VBNC and the recovered Staphylococcus aureus is the same as the normal bacteria in colony morphology and physiological and biochemical response in the common test medium.