Cloned (Comment) | Organism |
---|---|
gene ObktM, recombinant expression of wild-type and mutant enzymes in Saccharomaces cerevisiae strain BY4741, coexpression with gene OcrtZ encoding a beta-carotene 3-hydroxylase | Haematococcus lacustris |
Protein Variants | Comment | Organism |
---|---|---|
H165R/V264D/F298Y/M1T/N188D/L271R | site-directed mutagenesis, mutant OBKTM29 shows the best performance among all OBKTM mutants obtained by directed coevolution | Haematococcus lacustris |
additional information | construction of an efficient astaxanthin-producing Saccharomyces cerevisiae strain BY4741 by combining protein engineering and dynamic metabolic regulation. First, superior mutants of beta-carotene ketolase and beta-carotene hydroxylase are obtained by directed coevolution to accelerate the conversion of beta-carotene to astaxanthin. Subsequently, the Gal4M9-based temperature-responsive regulation system is introduced to separate astaxanthin production from cell growth. Finally, 235 mg/l of (3S,3'S)-astaxanthin is produced by two-stage, high-density fermentation. Color-based high-throughput screening for directed coevolution of beta-carotene ketolase and beta-carotene hydroxylase | Haematococcus lacustris |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
beta-carotene + 2 O2 + 2 reduced acceptor | Haematococcus lacustris | - |
echinenone + 3 H2O + 2 acceptor | - |
? | |
echinenone + 2 O2 + 2 reduced acceptor | Haematococcus lacustris | - |
canthaxanthin + 3 H2O + 2 acceptor | - |
? | |
additional information | Haematococcus lacustris | poor efficiency of beta-carotene ketolation and hydroxylation, as well as the adverse effect of astaxanthin accumulation on cell growth, in vivo. Canthxanthin is produced by beta-carotene ketolase, ObktM, from beta-carotene, canthaxanthin is then further metabolized by a beta-carotene hydroxylase, CrtZ, in the engineered yeast strain expressing both enzymes from Haematococcus pluvialis and Xanthophyllomyces dendrorhous, respectively | ? | - |
- |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Haematococcus lacustris | - |
Haematococcus pluvialis | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
beta-carotene + 2 O2 + 2 reduced acceptor | - |
Haematococcus lacustris | echinenone + 3 H2O + 2 acceptor | - |
? | |
echinenone + 2 O2 + 2 reduced acceptor | - |
Haematococcus lacustris | canthaxanthin + 3 H2O + 2 acceptor | - |
? | |
additional information | poor efficiency of beta-carotene ketolation and hydroxylation, as well as the adverse effect of astaxanthin accumulation on cell growth, in vivo. Canthxanthin is produced by beta-carotene ketolase, ObktM, from beta-carotene, canthaxanthin is then further metabolized by a beta-carotene hydroxylase, CrtZ, in the engineered yeast strain expressing both enzymes from Haematococcus pluvialis and Xanthophyllomyces dendrorhous, respectively | Haematococcus lacustris | ? | - |
- |
Synonyms | Comment | Organism |
---|---|---|
beta-carotene ketolase | - |
Haematococcus lacustris |
ObktM | - |
Haematococcus lacustris |
OBKTM29 | mutant enzyme | Haematococcus lacustris |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
in vivo assay at | Haematococcus lacustris |