Coenzyme M

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Coenzyme M
Coenzyme M (CoM).svg
Names
IUPAC name
2-Sulfanylethanesulfonate
Systematic IUPAC name
2-Sulfanylethanesulfonate
Other names
2-mercaptoethylsulfonate; 2-mercaptoethanesulfonate; coenzyme M anion; H-S-CoM; AC1L1HCY; 2-sulfanylethane-1-sulfonate; CTK8A8912
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
PubChem CID
UNII
  • InChI=1S/C2H6O3S2/c3-7(4,5)2-1-6/h6H,1-2H2,(H,3,4,5)/p-1 Yes check.svgY
    Key: ZNEWHQLOPFWXOF-UHFFFAOYSA-M Yes check.svgY
  • [O-]S(=O)(=O)CCS
Properties
C2H5O3S2
Molar mass 141.18 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Coenzyme M is a coenzyme required for methyl-transfer reactions in the metabolism of archaeal methanogens, [1] [2] and in the metabolism of other substrates in bacteria. [3] It is also a necessary cofactor in the metabolic pathway of alkene-oxidizing bacteria. CoM helps eliminate the toxic epoxides formed from the oxidation of alkenes such as propylene. [4] The structure of this coenzyme was discovered by CD Taylor and RS Wolfe in 1974 while they were studying methanogenesis, the process by which carbon dioxide is transformed into methane in some archaea. [5] The coenzyme is an anion with the formula HSCH
2
CH
2
SO
3
. It is named 2-mercaptoethanesulfonate and abbreviated HS–CoM. The cation is unimportant, but the sodium salt is most available. Mercaptoethanesulfonate contains both a thiol, which is the main site of reactivity, and a sulfonate group, which confers solubility in aqueous media.

Contents

Biochemical role

Methanogenesis

The coenzyme is the C1 donor in methanogenesis. It is converted to methyl-coenzyme M thioether, the thioether CH
3
SCH
2
CH
2
SO
3
, in the penultimate step to methane formation. [6] Methyl-coenzyme M reacts with coenzyme B, 7-thioheptanoylthreoninephosphate, to give a heterodisulfide, releasing methane:

CH3–S–CoM + HS–CoB → CH4 + CoB–S–S–CoM

This induction is catalyzed by the enzyme methyl-coenzyme M reductase, which restricts cofactor F430 as the prosthetic group.

Alkene metabolism

Coenzyme M is also used to make acetoacetate from CO2 and propylene or ethylene in aerobic bacteria. Specifically, in bacteria that oxidize alkenes into epoxides. After the propylene (or other alkene) undergoes epoxidation and becomes epoxypropane it becomes electrophilic and toxic. These epoxides react with DNA and proteins, affecting cell function. Alkene-oxidizing bacteria like Xanthobacter autotrophicus [4] use a metabolic pathway in which CoM is conjugated with an aliphatic epoxide. This step creates a nucleophilic compound which can react with CO2. The eventual carboxylation produces acetoacetate, breaking down the propylene. [4]

See also

Related Research Articles

In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula CH3. In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many organic compounds. It is a very stable group in most molecules. While the methyl group is usually part of a larger molecule, bonded to the rest of the molecule by a single covalent bond, it can be found on its own in any of three forms: methanide anion, methylium cation or methyl radical. The anion has eight valence electrons, the radical seven and the cation six. All three forms are highly reactive and rarely observed.

<span class="mw-page-title-main">Organic sulfide</span> Organic compound with an –S– group

In organic chemistry, a sulfide or thioether is an organosulfur functional group with the connectivity R−S−R' as shown on right. Like many other sulfur-containing compounds, volatile sulfides have foul odors. A sulfide is similar to an ether except that it contains a sulfur atom in place of the oxygen. The grouping of oxygen and sulfur in the periodic table suggests that the chemical properties of ethers and sulfides are somewhat similar, though the extent to which this is true in practice varies depending on the application.

<span class="mw-page-title-main">Cofactor (biochemistry)</span> Non-protein chemical compound or metallic ion

A cofactor is a non-protein chemical compound or metallic ion that is required for an enzyme's role as a catalyst. Cofactors can be considered "helper molecules" that assist in biochemical transformations. The rates at which these happen are characterized in an area of study called enzyme kinetics. Cofactors typically differ from ligands in that they often derive their function by remaining bound.

Methanogens are microorganisms that produce methane as a metabolic byproduct in hypoxic conditions. They belong to the domain Archaea and are members of the phylum Euryarchaeota. Methanogens are common in wetlands, where they are responsible for marsh gas, and can occur in the digestive tracts of animals including ruminants and humans, where they are responsible for the methane content of belching and flatulence. In marine sediments, the biological production of methane, termed methanogenesis, is generally confined to where sulfates are depleted below the top layers. Methanogens play an indispensable role in anaerobic wastewater treatments. Other methanogens are extremophiles, found in environments such as hot springs and submarine hydrothermal vents as well as in the "solid" rock of Earth's crust, kilometers below the surface in the deep biosphere.

Methanogenesis or biomethanation is the formation of methane coupled to energy conservation by microbes known as methanogens. Organisms capable of producing methane for energy conservation have been identified only from the domain Archaea, a group phylogenetically distinct from both eukaryotes and bacteria, although many live in close association with anaerobic bacteria. The production of methane is an important and widespread form of microbial metabolism. In anoxic environments, it is the final step in the decomposition of biomass. Methanogenesis is responsible for significant amounts of natural gas accumulations, the remainder being thermogenic.

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

Pterin is a heterocyclic compound composed of a pteridine ring system, with a "keto group" and an amino group on positions 4 and 2 respectively. It is structurally related to the parent bicyclic heterocycle called pteridine. Pterins, as a group, are compounds related to pterin with additional substituents. Pterin itself is of no biological significance.

<span class="mw-page-title-main">Methylcobalamin</span> Form of vitamin B12

Methylcobalamin (mecobalamin, MeCbl, or MeB12) is a cobalamin, a form of vitamin B12. It differs from cyanocobalamin in that the cyano group at the cobalt is replaced with a methyl group. Methylcobalamin features an octahedral cobalt(III) centre and can be obtained as bright red crystals. From the perspective of coordination chemistry, methylcobalamin is notable as a rare example of a compound that contains metal–alkyl bonds. Nickel–methyl intermediates have been proposed for the final step of methanogenesis.

Microbial metabolism is the means by which a microbe obtains the energy and nutrients it needs to live and reproduce. Microbes use many different types of metabolic strategies and species can often be differentiated from each other based on metabolic characteristics. The specific metabolic properties of a microbe are the major factors in determining that microbe's ecological niche, and often allow for that microbe to be useful in industrial processes or responsible for biogeochemical cycles.

Tetrahydromethanopterin is a coenzyme in methanogenesis. It is the carrier of the C1 group as it is reduced to the methyl level, before transferring to the coenzyme M.

Coenzyme B is a coenzyme required for redox reactions in methanogens. The full chemical name of coenzyme B is 7-mercaptoheptanoylthreoninephosphate. The molecule contains a thiol, which is its principal site of reaction.

<span class="mw-page-title-main">Wood–Ljungdahl pathway</span> A set of biochemical reactions used by some bacteria

The Wood–Ljungdahl pathway is a set of biochemical reactions used by some bacteria. It is also known as the reductive acetyl-coenzyme A (acetyl-CoA) pathway. This pathway enables these organisms to use hydrogen as an electron donor, and carbon dioxide as an electron acceptor and as a building block for biosynthesis.

In enzymology, a 2-oxopropyl-CoM reductase (carboxylating) (EC 1.8.1.5) is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">Coenzyme-B sulfoethylthiotransferase</span> Class of enzymes

In enzymology, coenzyme-B sulfoethylthiotransferase, also known as methyl-coenzyme M reductase (MCR) or most systematically as 2-(methylthio)ethanesulfonate:N-(7-thioheptanoyl)-3-O-phosphothreonine S-(2-sulfoethyl)thiotransferase is an enzyme that catalyzes the final step in the formation of methane. It does so by combining the hydrogen donor coenzyme B and the methyl donor coenzyme M. Via this enzyme, most of the natural gas on earth was produced. Ruminants produce methane because their rumens contain methanogenic prokaryotes (Archaea) that encode and express the set of genes of this enzymatic complex.

<span class="mw-page-title-main">Cofactor F430</span> Chemical compound

F430 is the cofactor (sometimes called the coenzyme) of the enzyme methyl coenzyme M reductase (MCR). MCR catalyzes the reaction EC 2.8.4.1 that releases methane in the final step of methanogenesis:

The enzyme 2-hydroxypropyl-CoM lyase (EC 4.4.1.23, epoxyalkane:coenzyme M transferase, epoxyalkane:CoM transferase, epoxyalkane:2-mercaptoethanesulfonate transferase, coenzyme M-epoxyalkane ligase, epoxyalkyl:CoM transferase, epoxypropane:coenzyme M transferase, epoxypropyl:CoM transferase, EaCoMT, 2-hydroxypropyl-CoM:2-mercaptoethanesulfonate lyase (epoxyalkane-ring-forming), (R)-2-hydroxypropyl-CoM 2-mercaptoethanesulfonate lyase (cyclizing, (R)-1,2-epoxypropane-forming)) is an enzyme with systematic name (R)-[or (S)]-2-hydroxypropyl-CoM:2-mercaptoethanesulfonate lyase (epoxyalkane-ring-forming). This enzyme catalyses the following reaction:

<i>Methanococcus maripaludis</i> Species of archaeon

Methanococcus maripaludis is a species of methanogenic archaea found in marine environments, predominantly salt marshes. M. maripaludis is a non-pathogenic, gram-negative, weakly motile, non-spore-forming, and strictly anaerobic mesophile. It is classified as a chemolithoautotroph. This archaeon has a pleomorphic coccoid-rod shape of 1.2 by 1.6 μm, in average size, and has many unique metabolic processes that aid in survival. M. maripaludis also has a sequenced genome consisting of around 1.7 Mbp with over 1,700 identified protein-coding genes. In ideal conditions, M. maripaludis grows quickly and can double every two hours.

The sulfate-methane transition zone (SMTZ) is a zone in oceans, lakes, and rivers typically found below the sediment surface in which sulfate and methane coexist. The formation of a SMTZ is driven by the diffusion of sulfate down the sediment column and the diffusion of methane up the sediments. At the SMTZ, their diffusion profiles meet and sulfate and methane react with one another, which allows the SMTZ to harbor a unique microbial community whose main form of metabolism is anaerobic oxidation of methane (AOM). The presence of AOM marks the transition from dissimilatory sulfate reduction to methanogenesis as the main metabolism utilized by organisms.

<span class="mw-page-title-main">C1 chemistry</span> One-carbon molecule chemical processes

C1 chemistry is the chemistry of one-carbon molecules. Although many compounds and ions contain only one carbon, stable and abundant C-1 feedstocks are the focus of research. Four compounds are of major industrial importance: methane, carbon monoxide, carbon dioxide, and methanol. Technologies that interconvert these species are often used massively to match supply to demand.

In enzymology, a formylmethanofuran dehydrogenase (EC 1.2.99.5) is an enzyme that catalyzes the chemical reaction:

Ralph Stoner Wolfe was an American microbiologist, who contributed to the discovery of the single-celled archaea as the third domain of life. He was a pioneer in the biochemistry of methanogenesis.

References

  1. Balch WE, Wolfe RS (1979). "Specificity and biological distribution of coenzyme M (2-mercaptoethanesulfonic acid)". J. Bacteriol. 137 (1): 256–63. doi:10.1128/JB.137.1.256-263.1979. PMC   218444 . PMID   104960.
  2. Taylor CD, Wolfe RS (10 August 1974). "Structure and methylation of coenzyme M(HSCH
    2
    CH
    2
    SO
    3
    )"
    . J. Biol. Chem. 249 (15): 4879–85. doi: 10.1016/S0021-9258(19)42403-4 . PMID   4367810.
  3. Partovi, Sarah E.; Mus, Florence; Gutknecht, Andrew E.; Martinez, Hunter A.; Tripet, Brian P.; Lange, Bernd Markus; DuBois, Jennifer L.; Peters, John W. (2018-04-06). "Coenzyme M biosynthesis in bacteria involves phosphate elimination by a functionally distinct member of the aspartase/fumarase superfamily". The Journal of Biological Chemistry. 293 (14): 5236–5246. doi: 10.1074/jbc.RA117.001234 . ISSN   1083-351X. PMC   5892593 . PMID   29414784.
  4. 1 2 3 Krishnakumar, Arathi M.; Sliwa, Darius; Endrizzi, James A.; Boyd, Eric S.; Ensign, Scott A.; Peters, John W. (September 2008). "Getting a Handle on the Role of Coenzyme M in Alkene Metabolism". Microbiology and Molecular Biology Reviews. 72 (3): 445–456. doi:10.1128/MMBR.00005-08. ISSN   1092-2172. PMC   2546864 . PMID   18772284.
  5. Parry, Ronald J. (1999-01-01), Barton, Sir Derek; Nakanishi, Koji; Meth-Cohn, Otto (eds.), "1.29 - Biosynthesis of Sulfur-containing Natural Products", Comprehensive Natural Products Chemistry, Oxford: Pergamon, pp. 825–863, doi:10.1016/b978-0-08-091283-7.00031-x, ISBN   978-0-08-091283-7 , retrieved 2022-05-10
  6. Thauer, Rudolf K. (1998-09-01). "Biochemistry of methanogenesis: a tribute to Marjory Stephenson:1998 Marjory Stephenson Prize Lecture". Microbiology. 144 (9): 2377–2406. doi: 10.1099/00221287-144-9-2377 . ISSN   1350-0872. PMID   9782487.