Structural model and functional properties of an exo-polygalacturonase from Neosartorya glabra.
Int J Biol Macromol
; 186: 909-918, 2021 Sep 01.
Article
em En
| MEDLINE
| ID: mdl-34274400
ABSTRACT
A purified exo-polygalacturonase of Neosartorya glabra (EplNg) was successfully characterized. EplNg native presented 68.2 kDa, with 32% carbohydrate content. The deglycosylated form showed 46.3 kDa and isoelectric point of 5.4. The identity of EplNg was confirmed as an exo-polygalacturonase class I (EC 3.2.1.67) using mass spectrometry and Western-Blotting. Capillary electrophoresis indicated that only galacturonic acid was released by the action of EplNg on sodium polypectate, confirming an exoenzyme character. The structural model confers that EplNg has a core formed by twisted parallel ß-sheets structure. Among twelve putative cysteines, ten were predicted to form disulfide bridges. The catalytic triad predicted is composed of Asp223, Asp245, and Asp246 aligned along with a distance in 4-5 Å, suggesting that EplNg probably does not perform the standard inverting catalytic mechanism described for the GH28 family. EplNg was active from 30 to 90 °C, with maximum activity at 65 °C, pH 5.0. The Km and Vmax determined using sodium polypectate were 6.9 mg·mL-1 and Vmax 690 µmol·min-1.mg-1, respectively. EplNg was active and stable over a wide range of pH values and temperatures, confirming the interesting properties EplNg and provide a basis for the development of the enzyme in different biotechnological processes.
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Bases de dados:
MEDLINE
Assunto principal:
Aspergillus
/
Proteínas Fúngicas
/
Glicosídeo Hidrolases
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Int J Biol Macromol
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Brasil