4.1.99.5 evolution cyanobacterial aldehyde-deformylating oxygenases belong to the ferritin-like diiron-carboxylate superfamily of dioxygen-activating proteins 727690 4.1.99.5 evolution structurally, the cADO enzyme belongs to the family of ferritin-like nonheme diiron-carboxylate enzymes that include methane monooxygenase (MMO), class I ribonucleotide reductase (RNR), and stearoyl-acyl carrier protein ?9-desaturase (DELTA9D), all of which share a common Fe2(His)2(O2CR)4 active site -, 748032 4.1.99.5 evolution the enzyme belongs to the superfamily of ferritin-like di-iron proteins with conserved sequence of two EX28-29EX2H motifs -, 749212 4.1.99.5 malfunction C71A/S mutations reduce the hydrocarbon producing activity of AD and facilitate the formation of a dimer, while mutations at Cys107 and Cys117 do not affect the hydrocarbon producing activity of the enzyme. The Cys-to-Ala/Ser mutations do not affect the iron binding to the enzyme. Structural features of the Cys-deficient mutants, overview -, 749051 4.1.99.5 malfunction the substrate preferences of some enzyme mutants towards different chain-length substrates are enhanced, e.g. I24Y for n-heptanal, I27F for n-decanal and n-dodecanal, V28F for n-dodecanal, F87Y for n-decanal, C70F for n-hexanal, A118F for n-butanal, A121F for C4,6,7 aldehydes, V184F for n-dodecanal and n-decanal, M193Y for C6-10 aldehydes and L198F for C7-10 aldehydes -, 747351 4.1.99.5 metabolism cyanobacterial aldehyde-deformylating oxygenase (cADO), which catalyzes the conversion of Cn fatty aldehyde to its corresponding Cn-1 alk(a/e)ne, is a key enzyme in fatty alk(a/e)ne biosynthesis pathway -, 749212 4.1.99.5 metabolism efficient delivery of long-chain fatty aldehydes from the Nostoc punctiforme acyl-acyl carrier protein reductase to its cognate aldehyde-deformylating oxygenase in a two-step pathway consisting of an acyl-acyl carrier protein (ACP) reductase (AAR) and an aldehyde-deformylating oxygenase (ADO) allowing various cyanobacteria to convert long-chain fatty acids into hydrocarbons. When the aldehyde substrate is supplied to ADO by AAR, efficient in vitro turnover is observed in the absence of solubilizing agents, even with insoluble substrates like octadec(a/e)nal, overview. AAR and ADO form a tight isolable complex with a Kd of 0.003 mM. The interaction between AAR and ADO facilitates either direct transfer of the aldehyde product of AAR to ADO or formation of the aldehyde product in a microenvironment allowing for its efficient uptake by ADO -, 747081 4.1.99.5 metabolism in cyanobacteria, aldehyde deformylating oxygenase catalyzes the decarbonylation of fatty aldehydes to the corresponding alkanes or alkenes, last step in the biosynthesis of long-chain aliphatic hydrocarbons, which are derived from fatty acids 726552 4.1.99.5 additional information comparison of the enzyme from Synechococcus elongates strain PCC 7942 and Synechocystis sp. PCC 6803, the first is more active than the latter against n-hexadecanal. Enzyme structure-function relationship analysis and comparisons, overview 747409 4.1.99.5 additional information Cys71, which is located in close proximity to the substrate-binding site, plays a crucial role in maintaining the activity, structure, and stability of the enzyme -, 749051 4.1.99.5 additional information Glu144, one of the iron-coordinating residues, plays a vital role in the catalytic reaction of cADO. The helix, in which Glu144 resides, exhibits two distinct conformations that correlate with the different binding states of the di-iron center in cADO structures. Enzyme structure analysis, comparisons of wild-type and mutant structures, overview. A continuous tube-shaped non-protein electron density, resembling a lipid molecule, is observed close to the di-iron center in all structures but the Y122F structure, a hydrophobic substrate channel in SeADO is described -, 749212 4.1.99.5 additional information residue L194, at the center of the hydrophobic cavity, might serve as a gateway for substrate entry, but L194 does not play a kinetically significant role in limiting substrate access to the active site. Structure of metal-free cADO, overview -, 746597 4.1.99.5 additional information residues close to the di-iron center (Tyr39, Gln110, Tyr122), the protein surface (Trp178), and involved in the hydrogen-bonding network (Arg62, Asp143) and the oligopeptide whose conformation changed (Leu/Thr146, Leu148, Asn149 and Tyr/Phe150) in the absence of the diiron center are identified. Comparison of the enzyme from Synechococcus elongates strain PCC 7942 and Synechocystis sp. PCC 6803, the first is more active than the latter against n-hexadecanal. Enzyme structure-function relationship analysis and comparisons, overview -, 747409 4.1.99.5 additional information solvent isotope effects on alkane formation by cyanobacterial aldehyde deformylating oxygenase and their mechanistic implications, overview -, 747074 4.1.99.5 additional information the definitive reaffirmation of the oxygenative nature of the reaction implies that the enzyme, initially designated as aldehyde decarbonylase when the C1-derived coproduct is thought to be carbon monoxide rather than formate, should be redesignated as aldehyde-deformylating oxygenase, ADO 727001 4.1.99.5 additional information the enzyme shows a mainly alpha helical architecture, with a ferritin-like four-helix bundle. The latter contains the di-iron centre, coordinated by two histidine residues and four carboxylates from glutamate side chains. Substrates access the active site through a tunnel-like hydrophobic pocket. Active site structure analysis from crystal structure, PDB ID 20C5 -, 727312 4.1.99.5 additional information the enzyme structure consists of eight a-helices found in ferritin-like di-iron proteins. Residues Tyr21, Ile27, Val28, Phe67, Phe86, Phe87, Phe117, Ala118, Ala121, Tyr122, Try125, and Tyr184 contributing to substrate binding, and Glu32, Glu60, His63, Glu115, Glu144, and His147 participating in iron coordination. OsADO structure resembles ADO structures with active sites containing both metal co-factor and substrate, OsADO active site is fully occupied, helix 5 of OsADO with an iron bound in the active site is a long helix 746976 4.1.99.5 additional information the enzyme structure consists of eight a-helices found in ferritin-like di-iron proteins. Residues Tyr21, Ile27, Val28, Phe67, Phe86, Phe87, Phe117, Ala118, Ala121, Tyr122, Try125, and Tyr184 contributing to substrate binding, and Glu32, Glu60, His63, Glu115, Glu144, and His147 participating in iron coordination. The LiADO structure resembles ADO structures with an empty active site, the LiADO active site is vacant of iron and substrates, helix 5 of LiADO, which lacks iron in the active site, presents two conformations (one long and two short helices), indicating that an equilibrium exists between the two states in solution -, 746976 4.1.99.5 additional information the synthetic iron(III)-peroxo complex [FeIII(eta2deltaO2)(TMC)]+ (TMC is tetramethylcyclam) causes a similar transformation in the presence of a suitable H atom donor, thus serving as a functional model for cADO, reaction analysis with undecanal with [FeIII(TMC)(delta2deltaO2)]+, detailed overview -, 748032 4.1.99.5 additional information the very low activity of the enzyme appears to result from inhibition by the ferredoxin reducing system used in the assay and the low solubility of the substrate -, 726957 4.1.99.5 physiological function aldehyde deformylating oxygenase is a key enzyme for alkane biosynthesis in cyanobacteria -, 749051 4.1.99.5 physiological function aldehyde-deformylating oxygenase (ADO) is a ferritin-like nonheme-diiron enzyme that catalyzes the last step in a pathway through which fatty acids are converted into hydrocarbons in cyanobacteria -, 748027 4.1.99.5 physiological function aldehyde-deformylating oxygenase (ADO) is an important enzyme involved in the biosynthetic pathway of fatty alk(a/e)nes in cyanobacteria -, 747351 4.1.99.5 physiological function aldehyde-deformylating oxygenase (ADO) is an important enzyme involved in the biosynthetic pathway of fatty alk(a/e)nes in cyanobacteria. ADO transforms the fatty aldehyde to a Cn-1 hydrocarbon and C1-derived formate -, 747081 4.1.99.5 physiological function alkane biosynthesis pathway 713511 4.1.99.5 physiological function cyanobacterial aldehyde-deformylating oxygenase (cADO) catalyzes the conversion of Cn fatty aldehyde to its corresponding Cn-1 alk(a/e)ne with low activity due to a highly labile feature of cADO di-iron center -, 749212 4.1.99.5 physiological function enzyme ADO natively catalyzes the conversion of long-chain aldehydes into corresponding alkanes. To convert short-chain isobutyraldehyde into propane efficiently, the substrate specificity of ADO has to be modified for the utilization of the short-chain aldehydes -, 747353 4.1.99.5 physiological function saturated fatty acids are converted to alkanes (and unsaturated fatty acids to alkenes) in cyanobacteria entailing scission of the C1-C2 bond of a fatty aldehyde intermediate by the enzyme aldehyde decarbonylase. The in vitro activity of the enzyme depends on the presence of a reducing system, i.e. NADPH, ferredoxin, and ferredoxin reductase 715293 4.1.99.5 physiological function the cyanobacterial aldehyde deformylating oxygenase (cADO) is a key enzyme that catalyzes the unusual deformylation of aliphatic aldehydes for alkane biosynthesis -, 746976 4.1.99.5 physiological function the nonheme diiron enzyme cyanobacterial aldehyde deformylating oxygenase, cADO, catalyzes the deformylation of aliphatic aldehydes to alkanes and formate -, 746597