8ACS

Crystal structure of FMO from Janthinobacterium svalbardensis

Summary for 8ACS

• Entry DOI: 10.2210/pdb8acs/pdb
• Descriptor: FAD-dependent oxidoreductase, FLAVIN-ADENINE DINUCLEOTIDE, GLYCEROL, ... (5 entities in total)
• Functional Keywords: flavin monooxygenase, type ii flavin monooxygenase, rossmann fold, fad, nadh, nadph, flavoprotein
• Biological source: Janthinobacterium svalbardensis
• Total number of polymer chains: 4
• Total formula weight: 278490.65

Authors

Polidori, N.,Galuska, P.,Gruber, K. (deposition date: 2022-07-06, release date: 2022-09-07, Last modification date: 2024-05-01)

Primary citation

Chanique, A.M.,Polidori, N.,Sovic, L.,Kracher, D.,Assil-Companioni, L.,Galuska, P.,Parra, L.P.,Gruber, K.,Kourist, R.
A Cold-Active Flavin-Dependent Monooxygenase from Janthinobacterium svalbardensis Unlocks Applications of Baeyer-Villiger Monooxygenases at Low Temperature.
Acs Catalysis, 13:3549-3562, 2023

PubMed Abstract: Cold-active enzymes maintain a large part of their optimal activity at low temperatures. Therefore, they can be used to avoid side reactions and preserve heat-sensitive compounds. Baeyer-Villiger monooxygenases (BVMO) utilize molecular oxygen as a co-substrate to catalyze reactions widely employed for steroid, agrochemical, antibiotic, and pheromone production. Oxygen has been described as the rate-limiting factor for some BVMO applications, thereby hindering their efficient utilization. Considering that oxygen solubility in water increases by 40% when the temperature is decreased from 30 to 10 °C, we set out to identify and characterize a cold-active BVMO. Using genome mining in the Antarctic organism a cold-active type II flavin-dependent monooxygenase (FMO) was discovered. The enzyme shows promiscuity toward NADH and NADPH and high activity between 5 and 25 °C. The enzyme catalyzes the monooxygenation and sulfoxidation of a wide range of ketones and thioesters. The high enantioselectivity in the oxidation of norcamphor (eeS = 56%, eeP > 99%, > 200) demonstrates that the generally higher flexibility observed in the active sites of cold-active enzymes, which compensates for the lower motion at cold temperatures, does not necessarily reduce the selectivity of these enzymes. To gain a better understanding of the unique mechanistic features of type II FMOs, we determined the structure of the dimeric enzyme at 2.5 Å resolution. While the unusual N-terminal domain has been related to the catalytic properties of type II FMOs, the structure shows a SnoaL-like N-terminal domain that is not interacting directly with the active site. The active site of the enzyme is accessible only through a tunnel, with Tyr-458, Asp-217, and His-216 as catalytic residues, a combination not observed before in FMOs and BVMOs.

PubMed: 36970468
DOI: 10.1021/acscatal.2c05160

Experimental method

X-RAY DIFFRACTION (2.5 Å)