Mozes-Koch Rita, Tanne Edna, Brodezki Alexandra, Yehuda Ran, Gover Ofer, Rabinowitch Haim D, Sela Ilan
The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, 76100 Rehovot, Israel.
J Biol Eng. 2017 Nov 21;11:44. doi: 10.1186/s13036-017-0062-7. eCollection 2017.
Previously we demonstrated that an entire bacterial operon (the PRN operon) is expressible in plants when driven by the Tomato -yellow-leaf-curl-virus (TYLCV) -derived universal vector IL-60.Petroleum-derived plastics are not degradable, and are therefore harmful to the environment. Fermentation of bacteria carrying operons for polyhydroxyalkanoates (PHAs) produces degradable bioplastics which are environmentally friendly. However, bacterial production of bioplastics is not cost-effective, and attention is turning to their production in plants. Such "green" plastics would be less expensive and environmentally friendly. Hence, attempts are being made to substitute petroleum-derived plastics with "green" plastics. However, transformation of plants with genes of operons producing bioplastics has deleterious effects. Transformation of plastids does not cause deleterious effects, however it is a complicated procedures.
We have developed another TYLCV-based vector (SE100) and show that yet another bacterial operon (the phaCAB operon) when driven by SE100 is also expressed in plants. We employed the combination of SE100 and the phaCAB operon to drive the operon to the plastids and produce in plants a biodegradable plastic [polyhydroxybutyrate (PHB)].Here we indicate that the bacterial operon (phaCAB), when driven by the newly developed universal plant vector SE100 is directed to chloroplasts and produces in plants PHB, a leading PHA. The PHB-producing plants circumvent the need for complicated technical procedures.
The viral vector system SE100 facilitated the production of the bio-plastic poly-3-hydroxybutyrate. This was achieved by using the full pha-CAB operon indicating that TYLCV based system can transcribe and translate genes from bacterial operons controlled by a single cis element. Our data hints to the participation of the chloroplasts in these processes.
此前我们证明，当由番茄黄化曲叶病毒（TYLCV）衍生的通用载体IL-60驱动时，整个细菌操纵子（PRN操纵子）可在植物中表达。石油衍生的塑料不可降解，因此对环境有害。携带聚羟基链烷酸酯（PHA）操纵子的细菌发酵可产生可降解的生物塑料，这些生物塑料对环境友好。然而，细菌生产生物塑料的成本效益不高，人们的注意力正在转向在植物中生产生物塑料。这种“绿色”塑料将更便宜且对环境友好。因此，人们正在尝试用“绿色”塑料替代石油衍生的塑料。然而，用产生生物塑料的操纵子基因转化植物具有有害影响。转化质体不会产生有害影响，然而这是一个复杂的过程。
我们开发了另一种基于TYLCV的载体（SE100），并表明当由SE100驱动时，另一个细菌操纵子（phaCAB操纵子）也能在植物中表达。我们利用SE100和phaCAB操纵子的组合将该操纵子导入质体，并在植物中生产出一种可生物降解的塑料[聚羟基丁酸酯（PHB）]。在此我们表明，当由新开发的通用植物载体SE100驱动时，细菌操纵子（phaCAB）被导向叶绿体，并在植物中产生PHB，一种主要的PHA。产生PHB的植物无需复杂的技术程序。
病毒载体系统SE100促进了生物塑料聚-3-羟基丁酸酯的生产。这是通过使用完整的pha-CAB操纵子实现的，表明基于TYLCV的系统可以转录和翻译由单个顺式元件控制的细菌操纵子中的基因。我们的数据暗示叶绿体参与了这些过程。
