Magnesium chelatase

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Magnesium chelatase
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Magnesium chelatase hetero12mer, Rhodobacter capsulatus
Identifiers
EC no. 6.6.1.1
CAS no. 9074-88-8
Databases
IntEnz IntEnz view
BRENDA BRENDA entry
ExPASy NiceZyme view
KEGG KEGG entry
MetaCyc metabolic pathway
PRIAM profile
PDB structures RCSB PDB PDBe PDBsum
Gene Ontology AmiGO / QuickGO
Search
PMC articles
PubMed articles
NCBI proteins
Magnesium chelatase, ChlI subunit
Identifiers
SymbolMg_chelatse_chII
Pfam PF01078
InterPro IPR000523
Available protein structures:
Pfam   structures / ECOD  
PDB RCSB PDB; PDBe; PDBj
PDBsum structure summary
PDB PDB: 1g8p
CobN/magnesium chelatase
Identifiers
SymbolCobN/Mg_chltase
Pfam PF02514
InterPro IPR003672
Available protein structures:
Pfam   structures / ECOD  
PDB RCSB PDB; PDBe; PDBj
PDBsum structure summary

Magnesium-chelatase is a three-component enzyme (EC 6.6.1.1) that catalyses the insertion of Mg2+ into protoporphyrin IX. This is the first unique step in the synthesis of chlorophyll and bacteriochlorophyll. [1] [2] As a result, it is thought that Mg-chelatase has an important role in channeling intermediates into the (bacterio)chlorophyll branch in response to conditions suitable for photosynthetic growth:

Magnesium chelatase.svg

protoporphyrin IX + Mg2+
+ ATP + H
2
O
ADP + phosphate + Mg-protoporphyrin IX + 2 H+

The four substrates of this enzyme are ATP, protoporphyrin IX, Mg2+, and H2O; its four products are ADP, phosphate, Mg-protoporphyrin IX, and H+.

This enzyme belongs to the family of ligases, specifically those forming nitrogen-D-metal bonds in coordination complexes. The systematic name of this enzyme class is Mg-protoporphyrin IX magnesium-lyase. Other names in common use include protoporphyrin IX magnesium-chelatase, protoporphyrin IX Mg-chelatase, magnesium-protoporphyrin IX chelatase, magnesium-protoporphyrin chelatase, magnesium-chelatase, Mg-chelatase, and Mg-protoporphyrin IX magnesio-lyase. This enzyme is part of the biosynthetic pathway to chlorophylls.

See also

Related Research Articles

<span class="mw-page-title-main">Chlorophyll</span> Green pigments found in plants, algae and bacteria

Chlorophyll is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words χλωρός, khloros and φύλλον, phyllon ("leaf"). Chlorophyll allow plants to absorb energy from light.

<span class="mw-page-title-main">Magnesium in biology</span> Use of Magnesium by organisms

Magnesium is an essential element in biological systems. Magnesium occurs typically as the Mg2+ ion. It is an essential mineral nutrient (i.e., element) for life and is present in every cell type in every organism. For example, adenosine triphosphate (ATP), the main source of energy in cells, must bind to a magnesium ion in order to be biologically active. What is called ATP is often actually Mg-ATP. As such, magnesium plays a role in the stability of all polyphosphate compounds in the cells, including those associated with the synthesis of DNA and RNA.

<span class="mw-page-title-main">Aminolevulinic acid</span> Endogenous non-proteinogenic amino acid

δ-Aminolevulinic acid, an endogenous non-proteinogenic amino acid, is the first compound in the porphyrin synthesis pathway, the pathway that leads to heme in mammals, as well as chlorophyll in plants.

Chlorophyll <i>a</i> Chemical compound

Chlorophyll a is a specific form of chlorophyll used in oxygenic photosynthesis. It absorbs most energy from wavelengths of violet-blue and orange-red light, and it is a poor absorber of green and near-green portions of the spectrum. Chlorophyll does not reflect light but chlorophyll-containing tissues appear green because green light is diffusively reflected by structures like cell walls. This photosynthetic pigment is essential for photosynthesis in eukaryotes, cyanobacteria and prochlorophytes because of its role as primary electron donor in the electron transport chain. Chlorophyll a also transfers resonance energy in the antenna complex, ending in the reaction center where specific chlorophylls P680 and P700 are located.

Chlorophyll <i>b</i> Chemical compound

Chlorophyll b is a form of chlorophyll. Chlorophyll b helps in photosynthesis by absorbing light energy. It is more soluble than chlorophyll a in polar solvents because of its carbonyl group. Its color is green, and it primarily absorbs blue light.

<span class="mw-page-title-main">Ferrochelatase</span>

Protoporphyrin ferrochelatase (EC 4.98.1.1, formerly EC 4.99.1.1, or ferrochelatase; systematic name protoheme ferro-lyase (protoporphyrin-forming)) is an enzyme encoded by the FECH gene in humans. Ferrochelatase catalyses the eighth and terminal step in the biosynthesis of heme, converting protoporphyrin IX into heme B. It catalyses the reaction:

<span class="mw-page-title-main">Protoporphyrin IX</span> Chemical compound

Protoporphyrin IX is an organic compound, classified as a porphyrin, that plays an important role in living organisms as a precursor to other critical compounds like heme (hemoglobin) and chlorophyll. It is a deeply colored solid that is not soluble in water. The name is often abbreviated as PPIX.

<span class="mw-page-title-main">Ribose-phosphate diphosphokinase</span> Class of enzymes

Ribose-phosphate diphosphokinase is an enzyme that converts ribose 5-phosphate into phosphoribosyl pyrophosphate (PRPP). It is classified under EC 2.7.6.1.

<span class="mw-page-title-main">Magnesium protoporphyrin IX methyltransferase</span>

In enzymology, a magnesium protoporphyrin IX methyltransferase is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">Divinyl chlorophyllide a 8-vinyl-reductase</span> Class of enzymes

In enzymology, divinyl chlorophyllide a 8-vinyl-reductase (EC 1.3.1.75) is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">Protochlorophyllide reductase</span>

In enzymology, protochlorophyllide reductases (POR) are enzymes that catalyze the conversion from protochlorophyllide to chlorophyllide a. They are oxidoreductases participating in the biosynthetic pathway to chlorophylls.

<span class="mw-page-title-main">Sirohydrochlorin ferrochelatase</span> Enzyme

The enzyme sirohydrochlorin ferrochelatase (EC 4.99.1.4) catalyzes the following reaction:

<span class="mw-page-title-main">Cobalt chelatase</span> Enzyme

Cobalt chelatase (EC 6.6.1.2) is an enzyme that catalyzes the chemical reaction

In enzymology, a Mg2+-importing ATPase (EC 3.6.3.2) is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">Chlorophyll synthase</span> Class of enzymes

In enzymology, chlorophyll synthase is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">Chlorophyllide-a oxygenase</span> Class of enzymes

Chlorophyllide-a oxygenase (EC 1.14.13.122), chlorophyllide a oxygenase, chlorophyll-b synthase, CAO) is an enzyme with systematic name chlorophyllide-a:oxygen 7-oxidoreductase. This enzyme catalyses the following chemical reactions

<span class="mw-page-title-main">Magnesium-protoporphyrin IX monomethyl ester (oxidative) cyclase</span> Class of enzymes

Magnesium-protoporphyrin IX monomethyl ester (oxidative) cyclase, is an enzyme with systematic name magnesium-protoporphyrin-IX 13-monomethyl ester, ferredoxin:oxygen oxidoreductase (hydroxylating). In plants this enzyme catalyses the following overall chemical reaction

<span class="mw-page-title-main">Chlorophyllide</span> Chemical compound

Chlorophyllide a and Chlorophyllide b are the biosynthetic precursors of chlorophyll a and chlorophyll b respectively. Their propionic acid groups are converted to phytyl esters by the enzyme chlorophyll synthase in the final step of the pathway. Thus the main interest in these chemical compounds has been in the study of chlorophyll biosynthesis in plants, algae and cyanobacteria. Chlorophyllide a is also an intermediate in the biosynthesis of bacteriochlorophylls.

<span class="mw-page-title-main">Chelatase</span> Class of enzymes

In biochemistry, chelatases are enzymes that catalyze the insertion ("metalation") of naturally occurring tetrapyrroles. Many tetrapyrrole-based cofactors exist in nature including hemes, chlorophylls, and vitamin B12. These metallo cofactors are derived by the reaction of metal cations with tetrapyrroles, which are not ligands per se, but the conjugate acids thereof. In the case of ferrochelatases, the reaction that chelatases catalyze is:

<span class="mw-page-title-main">Chlorophyllide a reductase</span> Enzyme

Chlorophyllide a reductase (EC 1.3.7.15), also known as COR, is an enzyme with systematic name bacteriochlorophyllide-a:ferredoxin 7,8-oxidoreductase. It catalyses the following chemical reaction

References

  1. Willows, Robert D. (2003). "Biosynthesis of chlorophylls from protoporphyrin IX". Natural Product Reports. 20 (6): 327–341. doi:10.1039/B110549N. PMID   12828371.
  2. Bollivar, David W. (2007). "Recent advances in chlorophyll biosynthesis". Photosynthesis Research. 90 (2): 173–194. doi:10.1007/s11120-006-9076-6. PMID   17370354. S2CID   23808539.