申请人:Feher Frank J.
公开号:US20110237769A1
公开(公告)日:2011-09-29
It has been found that certain cells in culture can convert more than about 0.002 percent of the carbon available in the cell culture medium into isoprene. These cells have a heterologous nucleic acid that (i) encodes an isoprene synthase polypeptide and (ii) is operably linked to a promoter. In some cases, these cells are cultured in a culture medium that includes a carbon source, such as, but not limited to, a carbohydrate, glycerol, glycerine, dihydroxyacetone, one-carbon source, oil, animal fat, animal oil, fatty acid, lipid, phospholipid, glycerolipid, monoglyceride, diglyceride, triglyceride, renewable carbon source, polypeptide (e.g., a microbial or plant protein or peptide), yeast extract, component from a yeast extract, or any combination of two or more of the foregoing. The isoprene produced in such a cultured medium can then be recovered and polymerized into synthetic rubbers and other useful polymeric materials. It is anticipated that there will be a significant demand for synthetic rubber and other isoprene containing polymers that are synthesized using isoprene of this type which is made from renewable, non-petrochemical based resources. In fact, it is believed that industrial customers and consumers would prefer to purchase isoprene containing polymers that are derived from such environmentally friendly sources to those that are made with isoprene derived from a petrochemical process. It is further believed that customers would be willing to pay premium prices for such environmentally friendly products that are made with renewable resources. However, it is important to be able to verify that such isoprene containing polymers are actually made from non-petrochemical based resources. The synthetic isoprene containing polymers of this invention offer the benefit of being verifiable as to being derived from non-petrochemical based resources. They can also be analytically distinguished from rubbers that come from natural sources. The present invention more specifically discloses a polyisoprene polymer which is comprised of repeat units that are derived from isoprene monomer, wherein the polyisoprene polymer has δ
13
C value of greater than −22‰. This type of polyisoprene can be a cis-1,4-polyisoprene homopolymer rubber.
已经发现,在培养基中的某些细胞可以将细胞培养基中可用的碳转化为异戊二烯超过约0.002%。这些细胞具有异源核酸,该核酸(i)编码异戊二烯合成酶多肽,并且(ii)与启动子可操作地连接。在某些情况下,这些细胞在包括碳源的培养基中培养,例如但不限于碳水化合物,甘油,甘油,二羟基乙酮,一碳源,油,动物脂肪,动物油,脂肪酸,脂质,磷脂,甘油脂,单甘酯,二甘酯,三甘酯,可再生碳源,多肽(例如微生物或植物蛋白质或肽),酵母提取物,来自酵母提取物的成分或任何两种或两种以上的组合。在这样的培养基中产生的异戊二烯然后可以被回收并聚合成合成橡胶和其他有用的聚合材料。预计将有相当大的需求,用这种由可再生,非石化基础资源制成的异戊二烯合成的合成橡胶和其他含异戊二烯聚合物。事实上,工业客户和消费者相信会更愿意购买从这些环保友好来源衍生的含异戊二烯聚合物,而不是使用从石化过程中衍生的异戊二烯制成的产品。此外,相信客户愿意为使用可再生资源制成的这些环保友好产品支付溢价价格。然而,能够验证这些含异戊二烯聚合物实际上是由非石化基础资源制成的非常重要。本发明更具体地披露了一种聚异戊二烯聚合物,其由异戊二烯单体衍生的重复单元组成,其中聚异戊二烯聚合物具有大于-22‰的δ13C值。这种聚异戊二烯可以是顺式-1,4-聚异戊二烯同聚物橡胶。