3939 results about "Isoprene" patented technology

The present invention provides methods for a robust production of isoprenoids via one or more biosynthetic pathways. The invention also provides nucleic acids, enzymes, expression vectors, and genetically modified host cells for carrying out the subject methods. The invention also provides fermentation methods for high productivity of isoprenoids from genetically modified host cells.

The present invention provides methods of producing an isoprenoid or an isoprenoid precursor in a genetically modified host cell. The methods generally involve modulating the level of hydroxymethylglutaryl-CoA (HMG-CoA) in the cell, such that the level of HMG-CoA is not toxic to the cell and / or does not substantially inhibit cell growth, but is maintained at a level that provides for high-level production of mevalonate, IPP, and other downstream products of an isoprenoid or isoprenoid pathway, e.g., polyprenyl diphosphates and isoprenoid compounds. The present invention further provides genetically modified host cells that are suitable for use in a subject method. The present invention further provides recombinant nucleic acid constructs for use in generating a subject genetically modified host cell, including recombinant nucleic acid constructs comprising nucleotide sequences encoding one or more mevalonate pathway enzymes, and recombinant vectors (e.g., recombinant expression vectors) comprising same. The present invention further provides methods for identifying nucleic acids that encode HMG-CoA reductase (HMGR) variants that provide for relief of HMG-CoA accumulation-induced toxicity. The present invention further provides methods for identifying agents that reduce intracellular accumulation of HMG-CoA.

This invention relates to a pneumatic tire having a built-in sealant layer and its preparation. The sealant layer precursor is a layer of a butyl rubber based composition which contains an organoperoxide. The butyl rubber of said precursor is a copolymer of isobutylene and isoprene containing from about 0.5 to about 5, alternately less than 1, mole percent isoprene. The precursor composition contains carbon black and / or coal dust and may contain a dispersion of liquid conjugated diene polymer (e.g. liquid cis 1,4-polyisoprene polymer), short fibers and / or hollow glass microspheres. A layer of the sealant precursor is built into the tire between a sulfur vulcanized halobutyl rubber innerliner and conjugated diene-based rubber of the tire carcass. The butyl rubber of the sealant precursor is partially depolymerized by the organoperoxide during the elevated temperature vulcanization of the tire to form the built-in sealant layer. In one aspect of the invention, said uncured butyl rubber sealant precursor layer composition has a storage modulus G′ (80° C.) in a range of about 100 to about 400 kPa and said partially depolymerized butyl rubber sealant layer composition has a storage modulus G′ (80° C.) in range of about 5 to about 50 kPa.

A thermoplastic elastomer composition comprised of (a) a thermoplastic resin selected from the group consisting of polyphenylene ether, polypropylene, polyethylene, and polystyrene, (b) a block copolymer selected from the group consisting of styrene-ethylene butylene-styrene, styrene-ethylene propylene-styrene, hydrogenated polybutadiene, hydrogenated polyisoprene, hydrogenated styrene-isoprene random copolymer, styrene-ethylene propylene block copolymer, styrene-ethylene ethylene propylene-styrene and hydrogenated styrene-butadiene random copolymers, (c) a core-shell polymer comprised of a polymeric core and a polymeric shell with the proviso that the polymeric core and / or the polymeric shell may be crosslinked, and (d) an oil.