The present invention relates to a selective process for preparing sulfones from sulfides by enzymatic catalysis, and to a composition comprising a symmetrical sulfide, an oxidoreductase enzyme catalyzing the oxidation of said symmetrical sulfide to symmetrical sulfone; optionally at least one cofactor C of said enzyme E; and an oxidant, which allows in particular the implementation of said process.

Methods and compositions for the oxidation of short alkanes by engineered microorganisms expressing enzymes are described, along with methods of use.

Provided herein are methods, compositions, and non-naturally occurring microbial organism for preparing compounds such as α-butanol, butyric acid, succinic acid, 1,4-butanediol, 1-pentanol, pentanoic acid, glutaric acid, 1,5-pentanediol, 1-hexanol, hexanoic acid, adipic acid, 1,6-hexanediol, 6-hydroxy hexanoic acid, ε-Caprolactone, 6-amino-hexanoic acid, ε-Caprolactam, hexamethylenediamine, linear fatty acids and linear fatty alcohols that are between 7-25 carbons long, linear alkanes and linear α-alkenes that are between 6-24 carbons long, sebacic acid and dodecanedioic acid comprising: a) converting a C.sub.N aldehyde and pyruvate to a C.sub.N+3 β-hydroxyketone intermediate through an aldol addition; and b) converting the C.sub.N+3 β-hydroxyketone intermediate to the compounds through enzymatic steps, or a combination of enzymatic and chemical steps.

A method of producing electrical power includes: a cathode having a porphyrin precursor attached to a substrate, and having a first enzyme, wherein the first enzyme reduces oxygen; an anode having a first region of an anode substrate and having a gold nanoparticle composition located thereon, and having a second region of the anode substrate having an enzyme composition located thereon, wherein the enzyme composition includes a second enzyme, wherein the first region and second region are separate regions; and a neutral fuel liquid in contact with the anode and cathode, the neutral fuel liquid having a neutral pH and a fuel reagent; and operating the fuel cell to produce electrical power with the neutral fuel liquid having the neutral pH and the fuel reagent.

Described herein are an immobilized enzyme, and a preparation method therefor and a use thereof. The immobilized enzyme includes activated PEI and an enzyme covalently bonded to the activated PEI, where the enzyme is selected from any one of a transaminase, a ketoreductase, a monooxygenase, an ammonia lyase, an ene-reductase, an imine reductase, an amino acid dehydrogenase and a nitrilase.

Multi-enzyme systems attached to nanoparticles are effective to efficiently and controllably incorporate stable isotopes (such as deuterium) during the synthesis of small molecules. In one example, deuterium is incorporated into (+)-dihydrocarvide using a cascade involving the enzymes (a) pentaerythritol tetranitrate reductase (PETNR) and (b) flavin-dependent cyclohexanone monooxygenase triple variant F249A/F280A/F435A (CHMO.sub.3M).

The invention relates to recombinant host cells having at least one integrated polynucleotide encoding a polypeptide that catalyzes a step in a pyruvate-utilizing biosynthetic pathway, e.g., pyruvate to acetolactate conversion. The invention also relates to methods of increasing the biosynthetic production of isobutanol, 2,3-butanediol, 2-butanol or 2-butanone using such host cells.

A method of producing electrical power includes: a cathode having a porphyrin precursor attached to a substrate, and having a first enzyme, wherein the first enzyme reduces oxygen; an anode having a first region of an anode substrate and having a gold nanoparticle composition located thereon, and having a second region of the anode substrate having an enzyme composition located thereon, wherein the enzyme composition includes a second enzyme, wherein the first region and second region are separate regions; and a neutral fuel liquid in contact with the anode and cathode, the neutral fuel liquid having a neutral pH and a fuel reagent; and operating the fuel cell to produce electrical power with the neutral fuel liquid having the neutral pH and the fuel reagent.

The present invention provides for a mechanism to reduce glycerol production and increase nitrogen utilization and ethanol production of recombinant microorganisms. One aspect of this invention relates to strains of S. cerevisiae with reduced glycerol productivity that get a kinetic benefit from higher nitrogen concentration without sacrificing ethanol yield. A second aspect of the invention relates to metabolic modifications resulting in altered transport and/or intracellular metabolism of nitrogen sources present in corn mash.

A ketoreductase mutant and use thereof are provided. The amino acid sequence of the ketoreductase mutant is an amino acid sequence obtained by mutation of the amino acid sequence shown in SEQ ID NO: 1, wherein the mutation at least comprises one of the following mutation sites: position 6, position 94, position 96, position 117, position 144, position 156, position 193, position 205, position 224, position 176, position 85 and position 108; alternatively, the amino acid sequence of the ketoreductase mutant has a mutation site in a mutated amino acid sequence and an amino acid sequence having 80% or more homology with the mutated amino acid sequence.