Sesquiterpenes are natural terpenes containing 15 carbon atoms. They are widely used in the perfume, pharmaceutical, and biofuel industries due to their remarkable biological activities. The traditional production of sesquiterpenes relies on chemical synthesis or plant extraction, which has the disadvantages of low yields and waste of resources. The construction of microbial cell factories for the efficient synthesis of sesquiterpenes by means of synthetic biology provides a new option. In recent years, with the development of metabolic engineering and synthetic biology, the heterologous synthesis of a variety of sesquiterpenes has been successfully achieved by metabolic engineering of the oleaginous yeast, Yarrowia lipolytica. In this paper, we review the research progress in the heterologous synthesis of different sesquiterpenes by Y. lipolytica, discuss the synthetic biology strategies commonly used in this field, and make an outlook on the research directions and engineering approaches to further enhance the sesquiterpene yield in this host. This paper provides a reference for strategies such as synergistic optimization of synthetic biology and metabolic engineering, enhanced precursors, and opens up new directions for the application of synthetic biology in green chemistry and sustainable production.
Yarrowia/genetics* ; Sesquiterpenes/metabolism* ; Metabolic Engineering/methods* ; Synthetic Biology/methods*

Objective To study the function of vascular endothelial growth factor (VEGF) in type 2 diabetes model rats and its effect on focal cerebral ischemia induced by middle cerebral artery occlusion in these rats. Methods Focal cerebral ischemia was induced by middle cerebral artery occlusion for 6 hours in type 2 diabetes rats and normal control rats.Blood vessels morphology was examined by ink perfusion,infarct size was measured by TTC and expression of VEGF and CD34 were evaluated by immunohistochemistry staining. Results Ink perfusion revealed increased number of small vessels in type 2 diabetes rats. Infarct size was significantly smaller in type 2 diabetes rats ( ( 80. 07 ± 11.21 ) mm3 ) than that in normal controls ((98. 91 ± 14. 86) mm3,t = 2.48,P = 0. 0326). There were more hemorrhage lesions in the ischemic hemisphere in type 2 diabetes rats when comparing with the controls. VEGF and CD34 showed significantly higher expression in type 2 diabetes rats than in normal controls. Conclusions High expression of VEGF and CD34 are found in type 2 diabetes rats after middle cerebral artery occlusion. There is cerebrolvascular remodeling in diabetes rats. While this diabetes-induced remodeling appears to prevent infarct expansion,the changes also increase the risk of hemorrhagic transformation. The latter may result in poor prognosis.