Investigations of Accessibility of T2/T3 Copper Center of Two-Domain Laccase from Streptomyces griseoflavus Ac-993

• Tipo: Artigo em Revista Científica Internacional
• Data: 2019

Autores

Gabdulkhakov, A (Autor) Outra; Kolyadenko, I (Autor) Outra; Kostareva, O (Autor) Outra; Mikhaylina, A (Autor) Outra; Oliveira, P (Autor) Outra; Paula Tamagnini (Autor) FCUP; Lisov, A (Autor) Outra; Tishchenko, S (Autor) Outra

Revista

Título: International Journal Of Molecular Sciences

Vol. 20

Página Final: 3184

ISSN: 1661-6596

Editora: MDPI

Indexação

ISI Web of Knowledge - 18 Citações

Scopus - 20 Citações

Outras Informações

ID Authenticus: P-00Q-WGD

DOI: 10.3390/ijms20133184

Abstract (EN): Laccases (EC 1.10.3.2) are multicopper oxidoreductases acting on diphenols and related substances. Laccases are highly important for biotechnology and environmental remediation. These enzymes contain mononuclear one T2 copper ion and two T3 copper ions (Cu3(alpha) and Cu3(beta)), which form the so-called trinuclear center (TNC). Along with the typical three-domain laccases Bacteria produce two-domain (2D) enzymes, which are active at neutral and basic pH, thermostable, and resistant to inhibitors. In this work we present the comparative analysis of crystal structures and catalytic properties of recombinant 2D laccase from Streptomyces griseoflavus Ac-993 (SgfSL) and its four mutant forms with replacements of two amino acid residues, located at the narrowing of the presumable T3-solvent tunnels. We obtained inactive enzymes with substitutions of His165, with Phe, and Ile170 with Ala or Phe. His165Ala variant was more active than the wild type. We suggest that His165 is a gateway at the O-2-tunnel leading from solvent to the Cu3(beta) of the enzyme. The side chain of Ile170 could be indirectly involved in the coordination of copper ions at the T3 center by maintaining the position of the imidazole ring of His157 that belongs to the first coordination sphere of Cu3(alpha).

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 13