EC Number   |
Application |
Reference |
|---|
   6.3.2.30 | synthesis |
cyanophycin produced in Escherichia coli is composed of 50% of aspartic acid, 45% of arginine, and 3.5% of lysine, and exhibits a homogenous molecular mass of 35 kDa. Cultivation in presence of arginine, aspartic acid, lysine and glucose with the minimal resource leads to 1.72 g/l soluble cyanophycin |
745413 |
| 6.3.2.30 | synthesis |
establishment of cyanophycin, i.e. multi-L-arginylpoly-L-aspartic acid or CGP, synthesis and applicability of this industrially widely used microorganism for the production of this polyamide, overview |
701820 |
| 6.3.2.30 | synthesis |
expression of cyanophycin synthase in wild-type Sinorhizobium meliloti 1021 and in a phbC-negative mutant. Yeast mannitol broth yields the highest cyanophycin contents in both Sinorhizobium meliloti 1021 strains. Supplying the medium with isopropyl-beta-D-thiogalactopyranoside, aspartic acid, and arginine enhances cyanophycin contents about 2.5- and 2.8fold. Varying the nitrogen-to-carbon ratio in the medium enhanced the cyanophycin content further to 43.8% w/w of cell dry weight. Cyanophycin from the Sinorhizobium meliloti strains consists of equimolar amounts of aspartic acid and arginine and contains no other amino acids even if the medium is supplemented with glutamic acid, citrulline, ornithine, or lysine. Cyanophycin isolated from Sinorhizobium meliloti exhibits average molecular weights between 20 and 25 kDa. Cyanophycin isolated after expression in Escherichia coli S17-1 exhibits average molecular weight between 22 and 30 kDa. Co-expression of cyanophycinase from Anabaena sp. PCC7120 encoded by cphB17120 in cphA17120-positive Escherichia coli S17-1, Sinorhizobium meliloti 1021, and its phbC-negative mutant gives cyanophycinase activities in crude extracts, and no CGP granules occur |
-, 713890 |
| 6.3.2.30 | synthesis |
expression of the cyanophycin synthetase of Synechocystis sp. PCC 6308 in Pseudomonas putida ATCC 4359 using an optimised medium for cultivation, results in synthesis of insoluble cyanophycin up to 14.7 w/w and soluble cyanophycin amounting up to 28.7 w/w of the cell dry matter. The soluble CGP is composed of 50.4 mol% aspartic acid, 32.7 mol% arginine, 8.7 mol% citrulline and 8.3 mol% lysine. The insoluble cyanophycin contains less than 1 mol% of citrulline. Using a mineral salt medium with 1.25 or 2% w/v sodium succinate, respectively, plus 23.7 mM L-arginine, the cells synthesise insoluble cyanophycin amounting up to 25% to 29% of the CDM with only a very low citrulline content |
-, 713906 |
| 6.3.2.30 | synthesis |
production of biodegradable polymers that can be used to substitute petrochemical compounds in commercial products by the recombinant enzyme in transgenic plants |
706150 |
| 6.3.2.30 | synthesis |
restriction of cyanophycin accumulation to the potato tubers by using the cyanophycin synthetase gene from Thermosynechococcus elongatus BP-1, under the control of the tuber-specific class 1 promoter. Tuber-specific cytosolic expression by pB33-cphATe as well as tuber-specific plastidic expression by pB33-PsbYcphATe results in significant polymer accumulation solely in the tubers. In plants transformed with pB33-cphATe, both cyanophycin synthetase and cyanophycin are detected in the cytoplasm leading to an increase up to 2.3% cyanophycin of dry weight and resulting in small and deformed tubers. In B33-PsbY-cphATe tubers, cyanophycin synthetase and cyanophycin are exclusively found in amyloplasts leading to a cyanophycin accumulation up to 7.5% of dry weight. These tubers are normal in size, some clones show reduced tuber yield and sometimes exhibit brown sunken staining starting at tubers navel. During a storage period over of 32 weeks of one selected clone, the cyanophycin content was stable in B33-PsbYcphATe tubers but the stress symptoms increased. Nitrogen fertilization in the greenhouse does not lead not to an increased cyanophycin yield, slightly reduced protein content, decreased starch content, and changes in the amounts of bound and free arginine and aspartate |
706150 |
| 6.3.2.30 | synthesis |
synthesis of cyanophycin using an anabolism-based media-dependent plasmid addiction system to enhance plasmid stability, and a process based on a modified mineral salts medium yielding a cyanophycin content of 42% w/w at the maximum without the addition of amino acids to the medium. This plasmid addiction system is based on different lysine biosynthesis pathways and consists of a knockout of the chromosomal dapE that disrupts the native succinylase pathway in Escherichia coli and the complementation by the plasmid-encoded artificial aminotransferase pathway mediated by the dapL gene from Synechocystis sp. PCC 6308, which allows the synthesis of the essential lysine precursor L,L-2,6-diaminopimelate. This plasmid also harbors an engineered cyanophycin synthetase gene responsible for cyanophycin production.Cultivation experiments reveal an at least 4.5fold enhanced production of cyanophycin in comparison to control cultivations |
-, 713897 |
