Time-resolved Fourier transform infrared spectrometry using a microfabricated continuous flow mixer: application to protein conformation study using the example of ubiquitin.
Lab Chip
; 3(2): 82-5, 2003 May.
Article
en En
| MEDLINE
| ID: mdl-15100787
ABSTRACT
We report on the use of time-resolved Fourier transform infrared spectroscopy (FT-IR) to study chemically induced conformational changes of proteins using the example of ubiquitin. For this purpose a micromachined mixer is coupled to a conventional IR transmission cell with a pathlength of 25 microm and operated in both the continuous and the stopped-flow mode. This experimental set-up allows the elucidation of reaction pathways in the time frame of about 500 milliseconds to seconds with little reagent consumption and low pressure. For continuous flow measurements employed in the time frame from 0.5 to 1.4 s the reaction time is determined by the flow rate used as the connection between the point of confluence in the micromixer and the flow cell was kept constant in all experiments. For stopped-flow experiments (>1.4 s) the time is determined by data acquisition of the rapid scanning infrared spectrometer. Ubiquitin, a small well-known protein with 76 amino acid residues, changes its conformation from native to A-state with the addition of methanol under low pH conditions. We investigated the conformational change in the time frame from 0.5 to 10 s by mixing ubiquitin (20% methanol-d(4)) with an 80% methanol-d(4) solution at pD 2 by evaluating the time dependent changes in the amide I band of the protein.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Espectroscopía Infrarroja por Transformada de Fourier
/
Ubiquitina
Idioma:
En
Revista:
Lab Chip
Asunto de la revista:
BIOTECNOLOGIA
/
QUIMICA
Año:
2003
Tipo del documento:
Article
País de afiliación:
Reino Unido