Pd-Oxazolone complexes conjugated to an engineered enzyme: improving fluorescence and catalytic properties

Garcia-Sanz, C. ; Andreu, A. ; de las Rivas, B. ; Jimenez, A.I. ; Pop, A. ; Silvestru, C. ; Urriolabeitia, E.P. ; Palomo, J.M.

Resumen: Different Pd-complexes containing orthometallated push-pull oxazolones were inserted by supramolecular Pd-amino acid coordination on two genetically engineered modified variants of the thermoalkalophilicGeobacillus thermocatenolatuslipase (GTL). Pd-lipase conjugation was performed on the solid phase in the previously immobilized form of GTL under mild conditions, and soluble conjugated Pd-GTL complexes were obtained by simply desorbing by washing with an acetonitrile aqueous solution. Three different Pd complexes were incorporated into two different genetically modified enzyme variants, one containing all the natural cysteine residues changed to serine residues, and another variant including an additional Cys mutation directly in the catalytic serine (Ser114Cys). The new Pd-enzyme conjugates were fluorescent even at ppm concentrations, while under the same conditions free Pd complexes did not show fluorescence at all. The Pd conjugation with the enzyme extremely increases the catalytic profile of the corresponding Pd complex from 200 to almost 1000-fold in the hydrogenation of arenes in aqueous media, achieving in the case of GTL conjugated with orthopalladated4aan outstanding TOF value of 27¿428 min-1. Also the applicability of GTL-C114 conjugated with orthopalladated4bin a site-selective C-H activation reaction under mild conditions has been demonstrated. Therefore, the Pd incorporation into the enzyme produces a highly stable conjugate, and improves remarkably the catalytic activity and selectivity, as well as the fluorescence intensity, of the Pd complexes.

Idioma: Inglés

DOI: 10.1039/d1ob00305d

Año: 2021

Publicado en: Organic & Biomolecular Chemistry 19, 12 (2021), 2773-2783
ISSN: 1477-0520

Factor impacto JCR: 3.89 (2021)

Categ. JCR: CHEMISTRY, ORGANIC rank: 13 / 56 = 0.232 (2021) - Q1 - T1

Factor impacto CITESCORE: 6.5 - Biochemistry, Genetics and Molecular Biology (Q2)

Factor impacto SCIMAGO: 0.832 - Physical and Theoretical Chemistry (Q1) - Organic Chemistry (Q1)

Financiación: info:eu-repo/grantAgreement/EUR/COST/CA15106-CHAOS
Financiación: info:eu-repo/grantAgreement/ES/DGA/E19-20R
Financiación: info:eu-repo/grantAgreement/ES/DGA-FEDER/LMP144-18
Financiación: info:eu-repo/grantAgreement/ES/MICINN/AGL2017-84614-C2-2-R
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2019-106394GB-I00

Tipo y forma: Artículo (Versión definitiva)