Application | Comment | Organism |
---|---|---|
agriculture | Because diphenylamine treatment leaves unwanted chemical residues on the fruit, restricts export markets, and creates environmental concerns, a long-range molecular genetic strategy for control of scald by reduction of (E,E)-alpha-farnesene synthesis in scald-susceptible apples is searched. The success of this strategy will rely on our ability to identify, clone, and characterize key genes involved in alpha-farnesene biosynthesis and its regulation by ethylene. | Malus domestica |
Cloned (Comment) | Organism |
---|---|
After screening a cDNA library generated from the peel tissue mRNA, a full-length terpene synthase cDNA 1931 nucleotides long is isolated (hot phenol RNA extraction protocol is used). The 1728-bp open reading frame encodes the 576 amino acid protein. Expression of the apple gene in Escherichia coli. | Malus domestica |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
1-methylcyclopropene | after treatment of fruits at harvest with a blocker of ethylene action, AFS1 mRNA declines sharply over the initial 4 weeks of cold storage, and falls to nearly undetectable levels by 8 weeks | Malus domestica |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cytosol | The encoded protein appears to lack approximately 20 amino acids that are present in the N-terminal chloroplast-targeting region of monoterpene synthases. Thus, the product of this TS gene is most likely localized in the cytosol. | Malus domestica | 5829 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
K+ | 500 mM are included in monoterpene synthase assay | Malus domestica | |
Mg2+ | 10 mM are included in sesquiterpene synthase assay | Malus domestica | |
Mn2+ | 1 mM is included in monoterpene synthase assay | Malus domestica |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
66000 | - |
without myc-epitope tag, determined by PAGE analysis | Malus domestica |
68000 | - |
with myc-epitope tag, determined by PAGE analysis | Malus domestica |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
farnesyl diphosphate | Malus domestica | sesquiterpene synthase activity | (E,E)-alpha-farnesene + diphosphate | - |
? | |
farnesyl diphosphate | Malus domestica | isomers of farnesene produced in apple fruit are (E,E)-alpha and (Z,E)-alpha are in a ratio of 300:1 | (Z,E)-alpha-farnesene + diphosphate | trace amounts | ? | |
geranyl diphosphate | Malus domestica | in monoterpene synthase assays, only (E)-beta-ocimene is produced at much reduced levels | (E)-beta-ocimene + diphosphate | - |
? | |
geranyl diphosphate | Malus domestica | monoterpene synthase activity | (Z)-beta-ocimene + diphosphate | - |
? | |
additional information | Malus domestica | other sesquiterpenes identified in trace amounts are (E)-nerolidol and beta-farnesene | ? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Malus domestica | Q84LB2 | The deduced amino acid sequence of this enzyme shares the greatest degree of homology with a variety of monoterpene synthases, including alpha-(-)beta-pinene synthase, a gamma-terpinene synthase, and a (+)-limonene synthase from Citrus limon, which have 41-42% amino acid identity. A geraniol synthase from Cinnamomum tenuipilum and an isoprene synthase from Populus tremuloides have 42% identity to AFS1. The closest homology is with a linalool/nerolidol synthase from Fragaria ananassa (35% identity) and a (+)-delta-cadinene synthase from Gossypium hirsutum (33% identity).; Malus domestica Borkh., cultivar Law Rome | - |
Renatured (Comment) | Organism |
---|---|
myc-tagged and untagged AFS1 expressed protein in bacterial inclusion-body fractions is urea-denatured, purified and renatured prior to assay of enzymatic activity. | Malus domestica |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
epidermal cell | production of (E,E)-alpha-farnesene occurs in the epidermal (peel tissue) or adjacent hypodermal cell layers and the sesquiterpene can accumulate to high levels in the natural epicuticular coating of scald-susceptible apples during the first weeks of storage | Malus domestica | - |
hypodermis | - |
Malus domestica | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
farnesyl diphosphate | sesquiterpene synthase activity | Malus domestica | (E,E)-alpha-farnesene + diphosphate | - |
? | |
farnesyl diphosphate | isomers of farnesene produced in apple fruit are (E,E)-alpha and (Z,E)-alpha are in a ratio of 300:1 | Malus domestica | (Z,E)-alpha-farnesene + diphosphate | trace amounts | ? | |
geranyl diphosphate | in monoterpene synthase assays, only (E)-beta-ocimene is produced at much reduced levels | Malus domestica | (E)-beta-ocimene + diphosphate | - |
? | |
geranyl diphosphate | monoterpene synthase activity | Malus domestica | (Z)-beta-ocimene + diphosphate | - |
? | |
additional information | other sesquiterpenes identified in trace amounts are (E)-nerolidol and beta-farnesene | Malus domestica | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
(E,E)-alpha-farnesene synthase | - |
Malus domestica |
AFS1 | - |
Malus domestica |
sesquiterpene synthase | - |
Malus domestica |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
assay at | Malus domestica |
Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|
additional information | - |
AFS1 transcript increases about 4fold in peel tissue of apple fruit during the first 4 weeks of storage at 0.5°C | Malus domestica |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.3 | - |
sesquiterpene synthase assay | Malus domestica |
7.5 | - |
monoterpene synthase assay | Malus domestica |
pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|
7 | 8 | maximal sesquiterpene synthase activity is observed | Malus domestica |
pH Stability | pH Stability Maximum | Comment | Organism |
---|---|---|---|
additional information | - |
sesquiterpene synthase activity declined below pH 7.0 and at pH 5.0-5.5, it is reduced more than 50% | Malus domestica |