A quantum-mechanical study of the reaction mechanism of sulfite oxidase.

Van Severen, Marie-CélineLund University,Lunds universitet,Beräkningskemi,Enheten för fysikalisk och teoretisk kemi,Kemiska institutionen,Institutioner vid LTH,Lunds Tekniska Högskola,Computational Chemistry,Physical and theoretical chemistry,Department of Chemistry,Departments at LTH,Faculty of Engineering, LTH (author)

The oxidation of sulfite to sulfate by two different models of the active site of sulfite oxidase has been studied. Both protonated and deprotonated substrates were tested. Geometries were optimized with density functional theory (TPSS/def2-SV(P)) and energies were calculated either with hybrid functionals and large basis sets (B3LYP/def2-TZVPD) including corrections for dispersion, solvation, and entropy, or with coupled-cluster theory (LCCSD(T0)) extrapolated toward a complete basis set. Three suggested reaction mechanisms have been compared and the results show that the lowest barriers are obtained for a mechanism where the substrate attacks a Mo-bound oxo ligand, directly forming a Mo-bound sulfate complex, which then dissociates into the products. Such a mechanism is more favorable than mechanisms involving a Mo-sulfite complex with the substrate coordinating either by the S or O atom. The activation energy is dominated by the Coulomb repulsion between the Mo complex and the substrate, which both have a negative charge of -1 or -2.

Andrejić, Milica (author)
Li, JilaiLund University,Lunds universitet,Beräkningskemi,Enheten för fysikalisk och teoretisk kemi,Kemiska institutionen,Institutioner vid LTH,Lunds Tekniska Högskola,Computational Chemistry,Physical and theoretical chemistry,Department of Chemistry,Departments at LTH,Faculty of Engineering, LTH(Swepub:lu)teok-jil (author)
Starke, KerstinLund University,Lunds universitet,Kemisk fysik,Enheten för fysikalisk och teoretisk kemi,Kemiska institutionen,Institutioner vid LTH,Lunds Tekniska Högskola,Chemical Physics,Physical and theoretical chemistry,Department of Chemistry,Departments at LTH,Faculty of Engineering, LTH(Swepub:lu)chem-kis (author)
Mata, Ricardo A (author)
Nordlander, EbbeLund University,Lunds universitet,Kemisk fysik,Enheten för fysikalisk och teoretisk kemi,Kemiska institutionen,Institutioner vid LTH,Lunds Tekniska Högskola,Chemical Physics,Physical and theoretical chemistry,Department of Chemistry,Departments at LTH,Faculty of Engineering, LTH(Swepub:lu)ook1-eno (author)
Ryde, UlfLund University,Lunds universitet,Beräkningskemi,Enheten för fysikalisk och teoretisk kemi,Kemiska institutionen,Institutioner vid LTH,Lunds Tekniska Högskola,Computational Chemistry,Physical and theoretical chemistry,Department of Chemistry,Departments at LTH,Faculty of Engineering, LTH(Swepub:lu)teok-ury (author)
BeräkningskemiEnheten för fysikalisk och teoretisk kemi (creator_code:org_t)

In:Journal of Biological Inorganic Chemistry: Springer Science and Business Media LLC19:7, s. 1165-11791432-13270949-8257

By the author/editor: Van Severen, Mar ...; Andrejić, Milica; Li, Jilai; Starke, Kerstin; Mata, Ricardo A; Nordlander, Ebbe; show more...; Ryde, Ulf; show less...

About the subject

NATURAL SCIENCES: NATURAL SCIENCES; and Physical Science ...; and Atom and Molecul ...

NATURAL SCIENCES: NATURAL SCIENCES; and Chemical Science ...; and Theoretical Chem ...

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.