Cloned (Comment) | Organism |
---|---|
recombinant expression of His-tagged enzyme in Escherichia coli strain BL21-Gold (DE3) | Streptomyces sp. CNH189 |
recombinant expression of His-tagged enzyme in Escherichia coli strain BL21-Gold (DE3) | Streptomyces sp. CNQ-525 |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Vanadium | required, vanadium-dependent haloperoxidases (VHPOs) are not redox active at the vanadium metal center, remaining in the V5+ oxidation state, and thus do not require additional regeneration systems nor suffer oxidative inactivation during catalysis | Streptomyces sp. CNH189 | |
Vanadium | required, vanadium-dependent haloperoxidases (VHPOs) are not redox active at the vanadium metal center, remaining in the V5+ oxidation state, and thus do not require additional regeneration systems nor suffer oxidative inactivation during catalysis | Streptomyces sp. CNQ-525 |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
RH + Cl- + H2O2 + H+ | Streptomyces sp. CNH189 | - |
RCl + 2 H2O | - |
? | |
RH + Cl- + H2O2 + H+ | Streptomyces sp. CNQ-525 | - |
RCl + 2 H2O | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Streptomyces sp. CNH189 | M4TL26 | - |
- |
Streptomyces sp. CNQ-525 | A7KH27 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant His-tagged enzyme from Escherichia coli strain BL21-Gold (DE3) by nickel affinity chromatography and alternating steps of ultrafiltration and desalting gel filtration, method overview | Streptomyces sp. CNH189 |
recombinant His-tagged enzyme from Escherichia coli strain BL21-Gold (DE3) by nickel affinity chromatography and alternating steps of ultrafiltration and desalting gel filtration, method overview | Streptomyces sp. CNQ-525 |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | in the napyradiomycin suite of molecules, VCPO NapH1 catalyzes the chloronium-induced cyclization of the dimethylallyl (prenyl) side chain of naphthomevalin to generate the tricyclic compound napyradiomycin A1, e.g. coverting methylated naphthomevalin analogue SF2415B1 isolated from Streptomyces aculeolatus NRRL 18442 to 7-methyl-napyradiomycin A1 (SF2415B3). Incubation of NapH1 with SF2415B1 in the presence of bromide facilitated a product consistent with bromonium-induced cyclization, which is a naturally produced napyradiomycin analogue. NapH1 halogenation is diastereoselective at the newly formed stereocenter at the chlorine atom, implying a specific facial chloronium formation and cyclization by the adjacent hydroxy group. NapH1 also catalyzes analogous chlorination and cyclization reactions on the des-methylated SF2415B1 substrate naphthomevalin. But NapH1 fails to show any catalytic activity on the linear terpene alcohol precursor ()-nerolidol or the related meroterpenoid-like compound lapachol, highlighting the extreme selectivity NapH1 has for its requisite substrate. Reactions catalyzed by NapH1 are also stereoselective, evidenced by the single enantiomer of napyradiomycin A1 generated from the synthetic, racemic naphthomevalin substrate. The concomitant, unreacted naphthomevalin recovered from a NapH1 assay, shows an opposite circular dichroism spectrum to naphthomevalin naturally isolated from Streptomyces bacteria or that produced in vitro by NapH3 reaction | Streptomyces sp. CNQ-525 | ? | - |
- |
|
additional information | VCPO Mcl24 from the merochlorin biosynthetic pathway shows an incredible ability to multitask, displaying all aforementioned VCPO function-alities (oxidative halogenation, terpene cyclization, and alpha-hydroxyketone rearrangement) within one enzyme. At pH 6.0, Mcl24 catalyzes the halogenation, oxidative dearomatization, and terpene cyclization of premerochlorin to generate two dominant monochlorinated merochlorins. These structurally divergent molecules arise due to the final terpene cyclization cascade ending with a carbon-carbon bond, or oxygen-carbon bond in merochlorins A and B, respectively. Under basic conditions (pH 8.0) the product distribution of Mcl24 is altered to predominantly catalyze the formation of merochlorin X, an alpha-hydroxyketone rearranged intermediate that may be further tailored by additional biosynthetic enzymes to generate merochlorins C and D. The major mechanistic difference during the biosyntheses of these molecules involves the addition of water to the oxidatively dearomatized molecule, which Mcl24 catalyzes more favorably at a basic pH. Hydration of the benzylic cation facilitates dichlorination and the corresponding rearrangement. in vitro, Mcl24 generates a large number of by-products because of the substantial oxidative instability of the premerochlorin substrate | Streptomyces sp. CNH189 | ? | - |
- |
|
RH + Cl- + H2O2 + H+ | - |
Streptomyces sp. CNH189 | RCl + 2 H2O | - |
? | |
RH + Cl- + H2O2 + H+ | - |
Streptomyces sp. CNQ-525 | RCl + 2 H2O | - |
? |
Synonyms | Comment | Organism |
---|---|---|
Mcl24 | - |
Streptomyces sp. CNH189 |
NapH1 | - |
Streptomyces sp. CNQ-525 |
vanadium-dependent chloroperoxidase | - |
Streptomyces sp. CNH189 |
vanadium-dependent chloroperoxidase | - |
Streptomyces sp. CNQ-525 |
vanadium-dependent haloperoxidase | - |
Streptomyces sp. CNH189 |
vanadium-dependent haloperoxidase | - |
Streptomyces sp. CNQ-525 |
vCPO | - |
Streptomyces sp. CNH189 |
vCPO | - |
Streptomyces sp. CNQ-525 |
VHPO | - |
Streptomyces sp. CNH189 |
VHPO | - |
Streptomyces sp. CNQ-525 |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
assay at | Streptomyces sp. CNH189 |
30 | - |
assay at | Streptomyces sp. CNQ-525 |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
6 | 8 | assay at | Streptomyces sp. CNH189 |
6 | 8 | assay at | Streptomyces sp. CNQ-525 |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
vanadate cofactor | the enzyme utilizes a vanadate prosthetic group to coordinate cosubstrate hydrogen peroxide, VHPOs perform a two-electron oxidation of electrophilic halides to generate a vanadium-bound hypohalous acid. This electrophilic halenium source can then react with electron-rich scaffolds, facilitating halogenation, cyclization, and hydration reactions | Streptomyces sp. CNH189 | |
vanadate cofactor | the enzyme utilizes a vanadate prosthetic group to coordinate cosubstrate hydrogen peroxide, VHPOs perform a two-electron oxidation of electrophilic halides to generate a vanadium-bound hypohalous acid. This electrophilic halenium source can then react with electron-rich scaffolds, facilitating halogenation, cyclization, and hydration reactions | Streptomyces sp. CNQ-525 |
General Information | Comment | Organism |
---|---|---|
metabolism | VCPO Mcl24 is involved in halogenated meroterpenoid biosynthesis | Streptomyces sp. CNH189 |
metabolism | VCPO NapH1 is involved in halogenated meroterpenoid biosynthesis | Streptomyces sp. CNQ-525 |
physiological function | vanadium-dependent haloperoxidases (VHPOs) enzymes facilitate electrophilic halogen incorporation into electron-rich substrates. They require vanadate, a halide source, and cosubstrate hydrogen peroxide for activity. In the napyradiomycin suite of molecules, VCPO NapH1 catalyzes the chloronium-induced cyclization of the dimethylallyl (prenyl) sidechain of naphthomevalin to generate the tricyclic compound napyradiomycin A1. VHPOs are responsible for halogenating the hybrid polyketide-terpenoid molecules | Streptomyces sp. CNQ-525 |
physiological function | vanadium-dependent haloperoxidases (VHPOs) enzymes facilitate electrophilic halogen incorporation into electron-rich substrates. They require vanadate, a halide source, and cosubstrate hydrogen peroxide for activity. VHPOs are responsible for halogenating the hybrid polyketide-terpenoid molecules | Streptomyces sp. CNH189 |