30 results about "Phytoene dehydrogenase" patented technology

The invention discloses a recombinant bacterium for producing beta-carotene as well as a construction method and application of the recombinant bacterium. The construction method comprises the following steps: respectively constructing superstrong gene expression modules of protein phytoene synthetase / lycopene cyclase coded by beta-carotene synthetic genes optimized by codons, phytoene dehydrogenase, protein geranyl diphosphate synthase coded by MAV (micro aerial vehicle) pathway genes and 3-hydroxy-3-methylglutaryl coenzyme A reductase; assembling the gene expression modules in vitro, so as to obtain four plasmids of the gene expression modules, integrating the plasmids into a host bacteria genome which does not produce beta-carotene and screening orange single colonies, so as to obtain the recombinant bacterium for producing beta-carotene. The recombinant bacterium disclosed by the invention is adopted for producing beta-carotene by fermental cultivation, and the yield of beta-carotene can reach 26.03mg / g DCW. Therefore, the recombinant bacterium has high performance of producing beta-carotene.

The invention provides a DNA sequence of a phytoene desaturase gene of sphingomonas sp., a recombinant strain with phytoene desaturase lost and application thereof. The phytoene desaturase gene (crtI) of the sphingomonas sp. has a nucleotide sequence shown by SEQ ID No.1. The DNA sequence of the phytoene desaturase gene (crtI) of the sphingomonas sp. provided by the invention lays a foundation for the genetic transformation of a biological synthesis manner of sphingomonas sp. carotene. Moreover, compared with the wild strains, the sphingomonas sp. recombinant strain with the phytoene desaturase lost, which is constructed by a gene knockout method, has gellan glue yield unchanged, generates no uranidin, reduces the amount of ethanol or isopropanol which is used during gellan glue extraction and therefore reduces the production cost of the gellan glue; meanwhile, the strain can also be applied to the further gene knockout or metabolic engineering transformation.

The invention relates to a phytoene dehydrogenase gene, in particular to a phytoene dehydrogenase gene for efficiently synthesizing lycopene and application thereof, belonging to the field of gene engineering. The nucleotide sequence of the phytoene dehydrogenase gene is shown by SEQ ID No.1. The amino acid sequence of the phytoene dehydrogenase coded with the gene is shown by SEQ ID No.2. The phytoene dehydrogenase gene provided by the invention can be used for efficiently producing lycopene. The examination results in that the yield of lycopene in a fermentation liquor is 0.269 mg / L and thecontent of lycopene in the dry weight of bacteria is 0.256 mg / g and accounts for 73.5% the total content of carotenoid; the phytoene dehydrogenase recombinase catalysate of rhodobacter azotoformans uses lycopene as the main pigment component and provides a new enzyme source for producing lycopene.