Thermostable single domain antibody-maltose binding protein fusion for Bacillus anthracis spore protein BclA detection.
Anal Biochem
; 447: 64-73, 2014 Feb 15.
Article
en En
| MEDLINE
| ID: mdl-24184358
ABSTRACT
We constructed a genetic fusion of a single domain antibody (sdAb) with the thermal stable maltose binding protein from the thermophile Pyrococcus furiosus (PfuMBP). Produced in the Escherichia coli cytoplasm with high yield, it proved to be a rugged and effective immunoreagent. The sdAb-A5 binds BclA, a Bacillus anthracis spore protein, with high affinity (K(D) â¼ 50 pM). MBPs, including the thermostable PfuMBP, have been demonstrated to be excellent folding chaperones, improving production of many recombinant proteins. A three-step purification of E. coli shake flask cultures of PfuMBP-sdAb gave a yield of approximately 100mg/L highly purified product. The PfuMBP remained stable up to 120 °C, whereas the sdAb-A5 portion unfolded at approximately 68 to 70 °C but could refold to regain activity. This fusion construct was stable to heating at 1mg/ml for 1h at 70 °C, retaining nearly 100% of its binding activity; nearly one-quarter (24%) activity remained after 1h at 90 °C. The PfuMBP-sdAb construct also provides a stable and effective method to coat gold nanoparticles. Most important, the construct was found to provide enhanced detection of B. anthracis Sterne strain (34F2) spores relative to the sdAb-A5 both as a capture reagent and as a detection reagent.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Temperatura
/
Proteínas Recombinantes de Fusión
/
Inmunoensayo
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Glicoproteínas de Membrana
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Proteínas Arqueales
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Proteínas de Unión a Maltosa
/
Anticuerpos de Dominio Único
Tipo de estudio:
Diagnostic_studies
Idioma:
En
Revista:
Anal Biochem
Año:
2014
Tipo del documento:
Article
País de afiliación:
Estados Unidos