Related Experiment Video
Updated: Jan 18, 2026
08:31
Anaerobic Protein Purification and Kinetic Analysis via Oxygen Electrode for Studying DesB Dioxygenase Activity and Inhibition
Published on: October 3, 2018
8.9K
Exploring Unspecific Peroxygenase Selectivity with Diverse Hydrocarbon Substrates
Essi Rytkönen1, Nina Hakulinen1, Janne Jänis1
1Department of Chemistry, University of Eastern Finland, P.O. Box 111, FI-80101, Joensuu, Finland.
Chemistryopen
|June 9, 2025
Summary
Unspecific peroxygenases (UPOs) efficiently oxidize hydrocarbons, producing multiple products. Protein engineering is needed to improve UPO selectivity for sustainable chemical production.
Area of Science:
- Biocatalysis
- Enzymology
- Organic Chemistry
Background:
- Unspecific peroxygenases (UPOs) are versatile enzymes utilizing hydrogen peroxide for oxidation.
- Their broad substrate specificity offers potential for synthesizing valuable compounds from inexpensive precursors.
- UPOs are of increasing interest for pharmaceutical and chemical building block synthesis.
Purpose of the Study:
- To screen a panel of 30 UPOs for activity against aliphatic and aromatic hydrocarbons.
- To assess variations in substrate selectivity among different UPOs.
- To understand the oxidation patterns and potential of UPOs in hydrocarbon functionalization.
Main Methods:
- Screening of 30 unspecific peroxygenases (UPOs).
- Testing activity against a diverse panel of aliphatic and aromatic hydrocarbons.
- Analysis of reaction products to determine selectivity and oxidation pathways (hydrogen abstraction, epoxidation).
Main Results:
- Most UPOs efficiently oxidized hydrocarbon substrates, yielding 2-5 products.
- Observed trends included preference for aromatic oxidation over benzylic hydroxylation (toluene) and vice-versa (ethylbenzene).
- Styrene and cyclohexene were selectively converted to epoxides, while other substrates produced mixtures, indicating low selectivity in general.
Conclusions:
- UPOs exhibit broad substrate scope for hydrocarbon oxidation, influenced by active site characteristics.
- While UPOs show potential for sustainable chemical synthesis, protein engineering is crucial to enhance selectivity.
- Further research into UPO active sites can unlock their full industrial potential.
Related Concept Videos
02:35Regioselectivity of Electrophilic Additions-Peroxide Effect
10.3K
In the presence of organic peroxides, the addition of hydrogen bromide to an alkene yields the isomer that is not predicted by Markovnikov’s rule. For example, the addition of hydrogen bromide to 2-methylpropene in the presence of peroxides gives 1-bromo-2-methylpropane. This addition reaction proceeds via a free radical mechanism, which reverses the regioselectivity. The free radical reaction mechanism involves three stages: initiation, propagation, and termination.
10.3K
03:08Hydroboration-Oxidation of Alkenes
11.1K
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
11.1K
02:44Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
12.6K
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
12.6K
01:24Peroxisomes
20.0K
Peroxisomes are specialized organelles present in fungi, plant, and animal cells. It can vary in number, size, morphology, and activity depending on the type of tissue and the nutritional state of the cell. For example, cells with active lipid metabolism, such as adipocytes, neurons, and hepatocytes, have more peroxisomes than other cells in the body. Besides their primary role in breaking down complex organic molecules, peroxisomes can also synthesize specific macromolecules and participate in...
20.0K
02:04Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
7.3K
Diols are compounds with two hydroxyl groups. In addition to syn dihydroxylation, diols can also be synthesized through the process of anti dihydroxylation. The process involves treating an alkene with a peroxycarboxylic acid to form an epoxide. Epoxides are highly strained three-membered rings with oxygen and two carbons occupying the corners of an equilateral triangle. This step is followed by ring-opening of the epoxide in the presence of an aqueous acid to give a trans diol.
7.3K
02:36Regioselectivity and Stereochemistry of Hydroboration
9.4K
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
9.4K